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Erschienen in: BMC Neurology 1/2017

Open Access 01.12.2017 | Research article

Inventory of real world data sources in Parkinson’s disease

verfasst von: Audrey Tanguy, Linus Jönsson, Lianna Ishihara

Erschienen in: BMC Neurology | Ausgabe 1/2017

Abstract

Background

Real world data have an important role to play in the evaluation of epidemiology and burden of disease; and in assisting health-care decision-makers, especially related to coverage and payment decisions. However, there is currently no overview of the existing longitudinal real world data sources in Parkinson’s disease (PD) in the USA. Such an assessment can be very helpful, to support a future effort to harmonize real world data collection and use the available resources in an optimal way.

Methods

The objective of this comprehensive literature review is to systematically identify and describe the longitudinal, real world data sources in PD in the USA, and to provide a summary of their measurements (categorized into 8 main dimensions: motor and neurological functions, cognition, psychiatry, activities of daily living, sleep, quality of life, autonomic symptoms and other). The literature search was performed using MEDLINE, EMBASE and internet key word search.

Results

Of the 53 data sources identified between May and August 2016, 16 were still ongoing. Current medications (81%) and comorbidities (79%) were frequently collected, in comparison to medical imaging (36%), genetic information (30%), caregiver burden (11%) and healthcare costs (2%). Many different measurements (n = 108) were performed and an interesting variability among used measurements was revealed.

Conclusions

Many longitudinal real world data sources on PD exist. Different types of measurements have been performed over time. To allow comparison and pooling of these multiple data sources, it will be essential to harmonize practices in terms of types of measurements.
Abkürzungen
BDI
Beck Depression Inventory
ESS
Epworth Sleepiness Scale
FDA
Food and Drug Administration
GDS
Geriatric Depression Scale
H&Y
Hoehn and Yahr scale
MMSE
Mini Mental State Examination
PD
Parkinson’s disease
PDQ-39
39-item Parkinson’s disease Quality of life
S&E
Schwab and England
SCOPA-AUT
autonomic part of the Scales for outcomes of Parkinson’s disease
UPDRS-III
Unified Parkinson’s Disease Rating Scale part III
USA
United States of America

Background

Parkinson’s disease (PD) is a progressive neurodegenerative disease affecting approximately 630,000 people in the USA and for which no disease-modifying therapy is currently available. With the ever growing ageing population, this number is projected to almost double to 1.1 million by 2030 [1].
The Food and Drug Administration (FDA) defines “real world data” as “all data collected from sources outside of traditional clinical trials” and “real world evidence” as “all evidence derived from aggregation and analysis of real world data” [2]. Such real world evidence reflecting disease progression, treatments and outcomes under conditions of routine clinical practice is a very important resource. It can take a pivotal role to improve the understanding of the underlying disease process [3], optimize currently available therapies and develop new treatment strategies [2, 4].
Although the burden of PD and the interest of real world data are well-known [5, 6], there has not been a literature review to present the overview of longitudinal, real world studies conducted in the USA on PD patients.
There is a need for a comprehensive review to create an integrated view and assist investigators and clinicians to optimize the measurements that best match with their objectives and the already existing data sources [4, 7]. Such an assessment can be very helpful, to support a future effort to harmonize real world data collection and use the available resources in an optimal way.
The objective of this comprehensive literature review is to systematically identify and describe the longitudinal, real world data sources in PD, and to provide a summary of the key characteristics and the measurements assessed in real world studies, as a part of an effort to mobilize a harmonization process, similar to the one that already takes place in Europe.

Methods

Search strategy and literature sources

The search was performed on ProQuest. It was based in MEDLINE on Pubmed, in EMBASE and internet key word search between May and August 2016. Related MeSH, EMTREE and key terms were combined. Articles from peer-reviewed journals, conference abstracts and reviews were screened (AT). The search equation terms are detailed in Appendix 1.

Study screening and selection

We included all studies including patients with a diagnosis of PD based on real world data. We restricted inclusion to only longitudinal, observational cohort studies and registries. The setting was restricted to the USA and the timing of publication in the last 10 years (2006-2016). Cohorts or registries without any publication in the last 10 years were considered as outdated. Exclusion criteria were based on population characteristics: Other diagnosis (e.g. Wolff-Parkinson-White disease or only Parkinsonian syndromes), autopsy data, and studies not focused on patients (e.g. focused on physicians). Moreover, studies without American patients or non-longitudinal studies, such as case-control, were also excluded. Only one main exclusion criterion was reported in the flow chart per excluded study (Fig. 1). No limits were applied for language.

Data extraction

In a first step, when a publication allowed the identification of a data source of interest, the detailed information available in the publication was extracted. Information on design and setting, funding, population selection, follow-up and measurements were recorded. This was supplemented and updated via information found with an internet search of the study website, registration sites such as clinicaltrials.​gov and investigators / funders’ websites. The list of all information captured is available in Appendix 2.
In a second step, a classification of measurements was performed for the following dimensions: motor and neurological function, cognition, psychiatric symptoms, activities of daily living, sleep quality, quality of life, autonomic symptoms and other. The “other” dimension gathers some known PD symptoms such as olfaction [8] not included in the previous main dimensions and more general information such as caregivers’ burden measurements. Some dimensions were subdivided in sub dimensions due to their complexity and variety (e.g. Motor and neurological symptoms is sub divided into 4 sub dimensions: global, gait and balance, fine movement and other). This classification was based on the literature [4] with one adaptation: as very few sensory markers were identified, they were gathered in the “other” category.

Data analysis

Data source characteristics were described globally. To address the variability of sources, the description was also performed according to four main characteristics: the completion status (ongoing vs completed); the study population (Parkinson specific data sources vs “generic” data sources including both Parkinsonian patients and patients of other diagnostics); the categories of studies (investigate for motor symptoms, non-motor symptoms, biomarkers, genetics or mixed); and the country (US only vs international sources). Descriptive statistics were reported as absolute frequency and percentages.

Results

Of 1463 records screened, 84% were excluded based on title and abstract, and 7% after review of the full-text (Fig. 1). The most frequent exclusion criterion was that studies were not longitudinal. Only 133 (9%) were included in the qualitative analysis. Of these 133 studies, data from 53 different data sources were extracted [961]. Only one registry was included with 52 cohorts.

Longitudinal real world sources (Table 1)

Forty-two sources (79%) were only in the USA. Three of the 11 international sources were only in North America while the other eight included patients in the USA and Europe, and two also included Asia. Most of the sources included less than 500 PD patients (79%) for more than 5 years (51%). Although most of the sources included information about current medications (81%) and comorbidities (79%); only few collected information on medical imaging (36%), genetics (30%), caregiver’ burden (11%) and healthcare costs (2%).
Table 1
Overview of data sources characteristics (n = 53)
Characteristics
Included
Status
Country
Study population
All (n = 53)
Ongoing (n = 16)
Completed (n = 37)
USA (n = 42)
International (n = 11)
Parkinson cohort
(n = 25)
“Generic” cohort
(n = 28)
Size (number of Parkinsonian patients)
 
0-500
42 (79)
11 (69)
31 (84)
37 (88)
5 (45)
22 (88)
20 (71)
500-1000
7 (13)
4 (25)
3 (8)
3 (7)
4 (36)
3 (12)
4 (14)
>1000
4 (8)
1 (6)
3 (8)
2 (5)
2 (18)
0 (0)
4 (14)
Duration of follow-up (years)
 
<2
6 (11)
0 (0)
6 (16)
4 (10)
2 (18)
4 (16)
2 (7)
2-5
20 (38)
4 (25)
16 (43)
16 (38)
4 (36)
13 (52)
7 (25)
≥5
27 (51)
12 (75)
15 (41)
22 (52)
5 (45)
8 (32)
19 (68)
Dimensions assessed
 
Motor and neurological
46 (87)
12 (75)
34 (92)
36 (86)
10 (91)
25 (100)
21 (75)
Cognition
41 (77)
13 (81)
28 (76)
36 (86)
5 (45)
17 (68)
24 (86)
Psychiatric symptoms
38 (72)
10 (63)
28 (76)
30 (71)
8 (73)
19 (76)
17 (61)
Activities of daily living
22 (42)
6 (38)
16 (43)
15 (36)
7 (64)
12 (48)
10 (36)
Sleep quality
11 (21)
4 (25)
7 (19)
5 (12)
6 (55)
2 (8)
9 (32)
Quality of life
9 (17)
4 (25)
5 (14)
5 (12)
4 (36)
6 (24)
3 (11)
Autonomic symptoms
7 (13)
4 (25)
3 (8)
3 (7)
4 (36)
0 (0)
7 (25)
Other
20 (38)
9 (56)
11 (30)
13 (31)
7 (64)
8 (32)
12 (43)
Other assessments
 
Current medications
43 (81)
13 (81)
30 (81)
32 (76)
11 (100)
22 (88)
21 (75)
Comorbidities
42 (79)
14 (88)
28 (76)
31 (74)
11 (100)
20 (80)
22 (79)
Medical imaging
19 (36)
6 (40)
13 (34)
11 (26)
8 (73)
6 (24)
13 (46)
Genetics
16 (30)
6 (38)
10 (27)
10 (24)
6 (55)
3 (12)
13 (46)
Caregiver burden
6 (11)
4 (27)
2 (5)
5 (12)
1 (9)
4 (16)
2 (7)
Healthcare costs
1 (2)
1 (7)
0 (0)
0 (0)
1 (9)
1 (4)
0 (0)
Data are shown as absolute frequency (percentage)
Among the 53 sources, 16 (30%) are still ongoing. There has been an increased availability of genetic information (38% vs 27%) and caregivers’ burden data (27% vs 5%) in ongoing versus completed sources, respectively. Moreover, there has been a trend toward larger inclusions and longer durations: comparing ongoing versus completed sources, 31% vs 16% included more than 500 patients and 75% vs 41% have a duration of more than 5 years.
Likewise, US sources were smaller and shorter than international sources (88% vs 45% included less than 500 PD patients, and 52% vs 45% have a duration of more than 5 years). US sources reported more caregiver burden data than international sources (12% vs 9%) but less frequently the other assessments such as medical imaging (26% vs 73%) or genetic information (24% vs 55%).
Sources including only Parkinsonian patients were smaller (12% vs 28% included more than 500 patients) and shorter (32% vs 68% had a duration of more than 5 years) than the “generic” cohorts. Medical imaging (24% vs 46%) and genetics (12% vs 46%) were less assessed in Parkinson’s specific than in “generic” cohorts.
The 53 data sources have different objectives. Mainly the sources investigated as their primary objective: non-motor symptoms (32%), then biomarkers (21%), motor symptoms (15%) and genetics (4%). Fifteen sources (28%) investigated several of these points as first objective. The sources investigating the biomarkers as primary objective were large and recent with four sources still ongoing and four sources begun in the last 5 years. In contrast, the sources investigating the motor symptoms as primary objective were small, all with less than 500 patients and with very frequent assessment, on average twice a year.

Measurements in real world studies in PD

The name of each included data source with its main characteristics (Table 2) and its measurements (Table 3) are presented individually. A large number of measurements (n = 108) was identified through this literature review and each of the 53 sources had its own unique range of measurements (Table 4). Most of the measurements were cited only once or twice. The distribution of the number of measurements over the different dimensions was not equal with only 3 different to assess autonomic symptoms and 43 to assess cognition.
Table 2
Overview of data sources characteristics listed in alphabetic order (n = 53)
Nb
Study
Acronym
Individuals included
Follow-up duration (y)
Planned follow-up
Main inclusion criteria
1
A Longitudinal Observational Follow-up of the PRECEPT Study Cohorta
PostCEPT
537
4
 
Post-RCT; under dopaminergic therapy
2
Abnormalities in metabolic network activity precede the onset of motor symptoms in Parkinson’s disease
 
15
4
Every 2 years
Hemi parkinsonism
3
Amyloid is linked to cognitive decline in patients with Parkinson disease without dementia
 
46
5
Annually
 
4
Arizona Study of Aging and Neurodegenerative Disease
AZSAND
3000
ongoing
  
5
Ashkenazi Jewish LRRK2 consortium cohort
LRRK2
2611
1.5
Every 12-18 months
Ashkenazi Jewish
6
Baltimore Longitudinal Study of Aging
BLSA
10,000?
ongoing
Every few years for life
Healthy
7
Boston university medical center - University of Alabama Birmingham - Washington University in Saint Louis School of medicine
 
80
2
 
>40 years
8
Central Control of Mobility in Aging
CCMA
439
ongoing
Annually
Elderly (>65 years); non demented
9
Cerebral glucose metabolic features of Parkinson disease and incident dementia: longitudinal study
 
50
4
Annually
Levodopa treatment
10
Charting the progression of disability in Parkinson disease
 
171
2
Every 6 months
>40 years; mild to moderate Parkinson’s disease
11
Clinical course in Parkinson’s disease with elevated homocysteine
 
97
2
Every 2 years
35-90 years without brain surgery or neurologic/psychiatric comorbidity
12
Clinical Research in Neurology (CRIN) - Emory center
CRIN
3581
15
  
13
Comparative utility of the BESTest; mini-BESTest; and brief-BESTest for predicting falls in individuals with Parkinson disease: a cohort study
BESTest
80
1
Every 6 months
Without neuropsychiatric comorbidities
14
Comparison of the Agonist Pramipexole With Levodopa on Motor Complications of Parkinson’s Diseasea
CALM-PD follow-up
301
2
Annually
Post-RCT; under dopaminergic therapy; diagnostic < 7 years
15
Contursi kindred
CONTURSI
210
?
  
16
Deprenyl and Tocopherol Antioxidative Therapy of Parkinsonisma
DATATOP
403
6
Every 3 months
Early phase; postRCT; 30-79 years
17
Depression in Parkinson’s disease
 
685
3.9
Annually
 
18
Dopamine agonist withdrawal syndrome in Parkinson diseasea
DAWS
93
0.25
Annually
Non demented
19
Einstein Aging Study (Bronx Aging Study)
EAS
791
ongoing
Every 12 to 18 months
Elderly (>70 years)
20
Emergence and evolution of social self-management of Parkinson’s disease
 
120
3
Every 6 months
Non demented
21
Hallucinations and sleep disorders in PD: ten-year prospective longitudinal study
 
89
10
0; 6 months; 18 months; 4 years; 6 years; 10 years
24-h caregiver; without neuroleptic treatment; without some comorbidities
22
Harvard Alumni Health Study
 
500,002
77
1962; 1966; 1972; 1988; 1993
Harvard students
23
Health Professionals Follow-up Study
HPFS
51,529
ongoing
Biannually
Men; healthy; 40-75 years
24
Honolulu Asia Aging Study
HAAS
3741
15
3 times between 1994 and 2001
Elderly Japanese-American men
25
Longitudinal study of normal cognition in Parkinson disease
 
141
6
Biannual for 4 years and annual after
Normal cognition at baseline
26
Long-term outcomes of bilateral subthalamic nucleus stimulation in patients with advanced Parkinson’s diseasea
 
33
2
0 –3 –6 –12 –18 – 24 months
Advanced phase with deep brain stimulation
27
Loss of ability to work and ability to live independently in Parkinson’s disease
 
495
10
  
28
Major life events and development of major depression in Parkinson’s disease patients
PEG study
221
4
Annually
New onset (within 3 years)
29
Mayo Clinic cohort study of Personality and Aging (including Rochester Epidemiology project)
 
7216
29.2
Historically for life
20-69 years
30
Mayo clinic study of aging (Olmsted county resident) - Rochester Epidemiology project indexing system
MCSA
2739
ongoing
  
31
Molecular Epidemiology of Parkinson’s Disease
MEPD
1600
ongoing
 
>40 years
32
Mood and motor trajectories in Parkinson’s disease: multivariate latent growth curve modeling
 
186
1.5
6 months; 18 months
 
33
Mood and Subthalamic Nucleus Deep Brain Stimulationa
MOST
91
1
 
Deep brain stimulation eligible; not demented
34
Morris K Udall Parkinson’s Disease Research Center of Excellence cohort - Veteran affair
Udall
314
ongoing
 
Elderly (>60 years)
35
National Parkinson Foundation Quality Improvement Initiative
NPF-QII
10,000
on going
  
36
NeuroGenetics Research Consortium
NGRC
3072
>10
  
37
Nurses’ Health Study
NHS
280,000
ongoing
Every 2 years
Women; healthy; 19-51 years
38
Oxford Parkinson’s Disease Centre
OPDC
1500
1.5
18 months
 
39
Parkinson’s Associated Risk Study
PARS
10,000
ongoing
 
Elderly (>60 years)
40
Parkinson’s Disease Biomarkers Program
PDBP
1436
ongoing
 
Evidence of response to dopaminergic medication
41
Parkinson’s Disease Research Education and Clinical Center - Parkinson’s Genetic Research Study
PADRECCS - PaGeR
1880
ongoing
  
42
Parkinson’s disease: increased motor network activity in the absence of movement
NMRP
12
4.4
Every 2 years
Non demented; tremor-dominant clinical manifestations; without some comorbidities
43
Parkinson’s Progression bioMarkers Initiative
PPMI
748
ongoing
Every 3 months the first year then every 6 months
Untreated recently diagnosed
44
Prospective cohort study of impulse control disorders in Parkinson’s disease
ICD-PD
164
4
 
Non demented
45
Rate of 6-18Ffluorodopa uptake decline in striatal subregions in Parkinson’s disease
 
37
4
Every 1 to 2 years
 
46
Religious Order Study
ROS
>1100
>7
Annually
Elderly; religious clergy
47
Rush Memory and Aging Project
RMAP
1556
5
Annually
Elderly without know dementia
48
Study of Osteoporotic Fractures (SOF) Research Group
SOF
9704
>6
Tri-annually
Women; Elderly (>65 years)
49
The effect of age of onset of PD on risk of dementia
 
440
4
Annually
Elderly (>65 years)
50
University of California Los Angeles Center for Genes and Environmental in Parkinson’s Disease
UCLA CGEP
363
5
 
Diagnostic >3 years
51
University of Miami Brain Endowment Bank
UM/BEB
150
ongoing
Annually
Consent to donate brain
52
UPDRS activity of daily living score as a marker of Parkinson’s disease progression
 
162
6
Every 2 years
 
53
Washington Heights-Inwood Columbia Aging
WHICAP
2776
3.7
Annually
Elderly (>65 years)
Post-RCT = Open label extension after a Randomized Controlled Trial
aTreatment directed data sources
Table 3
Overview of data source measurements and of the number of evaluations or assessments applied (n = 53)
Nb
Study
Motor and neurological
Cognition
Psychiatry
Activities of daily living
Sleep
Quality of life
Autonomic
Other
1
A Longitudinal Observational Follow-up of the PRECEPT Study Cohort
3
4
3
1
0
0
0
0
2
Abnormalities in metabolic network activity precede the onset of motor symptoms in Parkinson’s disease
2
0
0
0
0
0
0
0
3
Amyloid is linked to cognitive decline in patients with Parkinson disease without dementia
2
14
1
0
0
0
0
0
4
Arizona Study of Aging and Neurodegenerative Disease
4
12
3
0
1
0
1
1
5
Ashkenazi Jewish LRRK2 consortium cohort
3
2
2
2
1
0
1
1
6
Baltimore Longitudinal Study of Aging
0
2
3
0
0
0
0
0
7
Boston university medical center - University of Alabama Birmingham - Washington University in Saint Louis School of medicine
9
1
1
0
0
1
0
0
8
Central Control of Mobility in Aging
2
1
1
0
0
0
0
0
9
Cerebral glucose metabolic features of Parkinson disease and incident dementia: longitudinal study
1
6
0
0
0
0
0
0
10
Charting the progression of disability in parkinson disease
9
1
1
0
0
1
0
0
11
Clinical course in Parkinson’s disease with elevated homocysteine
1
9
1
1
0
0
0
0
12
Clinical Research in Neurology (CRIN) - Emory center
0
1
0
0
0
0
0
0
13
Comparative utility of the BESTest; mini-BESTest; and brief-BESTest for predicting falls in individuals with Parkinson disease: a cohort study
5
0
0
0
0
0
0
0
14
Comparison of the Agonist Pramipexole With Levodopa on Motor Complications of Parkinson’s Disease
3
1
2
2
1
3
0
0
15
Contursi kindred
1
1
1
1
1
0
1
1
16
Deprenyl and Tocopherol Antioxidative Therapy of Parkinsonism
2
5
0
0
0
0
0
0
17
Depression in Parkinson’s disease
2
0
1
1
0
0
0
0
18
Dopamine agonist withdrawal syndrome in parkinson disease
2
1
4
1
0
1
0
0
19
Einstein Aging Study (Bronx Aging Study)
2
11
1
0
0
0
0
0
20
Emergence and evolution of social self-management of Parkinson’s disease
2
2
1
1
0
4
0
0
21
Hallucinations and sleep disorders in PD: ten-year prospective longitudinal study
2
1
1
0
1
0
0
0
22
Harvard Alumni Health Study
0
0
0
0
0
0
0
0
23
Health Professionals Follow-up Study
0
0
0
0
0
0
0
0
24
Honolulu Asia Aging Study
2
4
2
0
1
0
1
1
25
Longitudinal study of normal cognition in Parkinson disease
2
6
2
1
0
0
0
0
26
Long-term outcomes of bilateral subthalamic nucleus stimulation in patients with advanced Parkinson’s disease
2
2
2
2
0
0
0
0
27
Loss of ability to work and ability to live independently in Parkinson’s disease
2
0
1
1
0
0
0
0
28
Major life events and development of major depression in Parkinson’s disease patients
1
2
2
0
0
0
0
0
29
Mayo Clinic cohort study of Personality and Aging (including Rochester Epidemiology project)
0
0
4
0
0
0
0
0
30
Mayo clinic study of aging (Olmsted county resident) - Rochester Epidemiology project indexing system
1
10
3
0
1
0
1
1
31
Molecular Epidemiology of Parkinson’s Disease
1
3
0
0
0
0
0
0
32
Mood and motor trajectories in Parkinson’s disease: multivariate latent growth curve modeling
1
0
2
0
0
0
0
0
33
Mood and Subthalamic Nucleus Deep Brain Stimulation
2
0
7
0
0
0
0
0
34
Morris K Udall Parkinson’s Disease Research Center of Excellence cohort - Veteran affair
2
3
2
1
0
1
0
1
35
National Parkinson Foundation Quality Improvement Initiative
3
2
0
0
0
1
0
1
36
NeuroGenetics Research Consortium
1
1
1
0
0
0
0
0
37
Nurses’ Health Study
0
5
0
0
0
0
0
0
38
Oxford Parkinson’s Disease Centre
6
3
2
1
2
1
0
2
39
Parkinson’s Associated Risk Study
0
0
2
0
0
0
0
1
40
Parkinson’s Disease Biomarkers Program
4
3
6
1
6
5
1
3
41
Parkinson’s Disease Research Education and Clinical Center - Parkinson’s Genetic Research Study
3
1
0
1
0
0
0
0
42
Parkinson’s disease: increased motor network activity in the absence of movement
2
1
0
0
0
0
0
0
43
Parkinson’s progression biomarkers initiative
1
5
4
2
2
0
1
2
44
Prospective cohort study of impulse control disorders in Parkinson’s disease
2
1
2
1
0
0
0
0
45
Rate of 6-18Ffluorodopa uptake decline in striatal subregions in Parkinson’s disease
2
1
0
0
0
0
0
0
46
Religious Order Study
6
11
4
1
0
0
0
0
47
Rush Memory and Aging Project
5
1
3
1
1
0
0
2
48
Study of Osteoporotic Fractures (SOF) Research Group
2
1
1
0
0
0
0
2
49
The effect of age of onset of PD on risk of dementia
1
6
1
0
0
0
0
0
50
University of California Los Angeles Center for Genes and Environmental in Parkinson’s Disease
2
1
1
0
0
0
0
0
51
University of Miami Brain Endowment Bank
1
0
0
1
0
0
0
2
52
UPDRS activity of daily living score as a marker of Parkinson’s disease progression
1
0
1
1
0
0
0
0
53
Washington Heights-Inwood Columbia Aging
1
6
0
1
0
0
0
0
Table 4
Measurements classification and use in data sources (n = 108)
Dimension
Measurement acronym
Measurement full name
Data sources (number and numbering)
Motor and neurological (n = 46)
Global
H&Y
Hoehn and Yahr
(n = 30) °1,2,3,4,5,7,9,10,13,14,16,17,18,20,21,25,26,27,31,33,34,35,38,40,41,42,44,45,50,51
UPDRS-III
Unified Parkinson’s Disease Rating Scale - motor examination
(n = 41) °1,2,3,4,5,7,8,10,11,13,14,16,17,18,19,20,21,24,25,26,27,28,30,32,33,34,35,36,38,40,41,42,43,44,45,46,47,49,50,52,53
UPDRS-IV
Unified Parkinson’s Disease Rating Scale - motor complications
(n = 2) n°1,14
Gait and balance
 
Berg balance test
(n = 2) n°7,10
 
Flamingo test
(n = 1) n°38
FGA
Functional Gait Assessment
(n = 2) n°7,10
FOGQ
Freezing of gait questionnaire
(n = 2) n°7,10
 
Gait speed
(n = 4) n°7,8,10,46
PIGD
Postural Instability / Gait Difficulty scale
(n = 2) n°5,40
 
Tandem gait
(n = 1) n°48
TUG
Time Up and Go test
(n = 6) n°7,10,35,38,40,47
 
Walk test
(n = 5) n°7,10,46,47,48
Fine movement
 
Finger tapping
(n = 3) n°4,46,47
 
Purdue pegboard test
(n = 6) n°4,7,10,38,46,47
 
Reaction time
(n = 1) n°24
 
Unknown
(n = 1) n°15
Cognition (n = 41)
Global
ACE
Addenbrooke’s Cognitive Examination
(n = 1) n°40
AD-8
Ascertian Dementia 8-item Informant
(n = 1) n°31
BDRS
Blessed Dementia Rating Scale
(n = 2) n°19,53
CAMCOG
Cambridge Cognitive Assessment
(n = 1) n°49
CASI
Cognitive Abilities Screening Instrument
(n = 1) n°24
CDR
Clinical Dementia Rating scale
(n = 5) n°3,4,6,19,30,53
 
Clock drawing test
(n = 1) n°4
DRS2
Dementia Rating Scale 2
(n = 6) n°4,19,25,26,34,53
HDS
Hasegawa Dementia Rating Scale
(n = 1) n°24
MDRS
Mattis Dementia Rating Scale
(n = 2) n°4,26
MMSE
Mini Mental State Examination
(n = 30) °1,3,4,5,7,9,10,11,12,14,15,16,18,20,21,24,26,28,31,34,36,37,38,42,44,45,46,47,48,50
MoCA
Montreal Cognitive Assessment
(n = 9) n°1,4,5,20,34,38,40,41,43
IQCODE
Informant Questionnaire on Cognitive Decline in Elderly
(n = 1) n°24
SPMSQ
Short Portable Mental Status Questionnaire
(n = 1) n°40
TICS-M
Telephone Interview Cognitive Status Modified
(n = 2) n°31,37
Attention/ Working memory
 
Digit span
(n = 6) n°3,4,11,30,37,46
 
STROOP test
(n = 2) n°4,11
Executive function
 
Comprehension
(n = 2) n°28,49
RBANS
Repeatable Battery for Assessment of Neuropsychological Status
(n = 1) n°8
 
Symbol digit
(n = 3) n°16,43,46
 
Trail Making Test
(n = 4) n°3,4,19,30
 
Verbal fluency
(n = 12) n°3,9,11,19,25,30,35,37,38,43,46,49
Language
BNT
Boston Naming Test
(n = 5) n°3,25,30,37,46
COWA
Controlled Oral Word Association
(n = 4) n°1,3,4,11
FAS
Letter-Number Sequencing and Phonemic verbal fluency
(n = 2) n°11,25
 
Naming
(n = 1) n°49
NART
American National Adult Reading test
(n = 2) n°3,46
WAIS
Wechlser Adult Intelligence Scale
(n = 6) n°3,4,9,11,19,30
Memory
BIMC
Blessed Information Memory Concentration
(n = 2) n°6,19
FCSRT
Free and Cue Selective Reminding Test
(n = 2) n°3,19
FOME
Fuld Object Memory Evaluation
(n = 1) n°19
HVLT
Hopkins Verbal Learning test
(n = 3) n°11,25,43
 
Memory
(n = 5) n°3,16,35,46,53
RAVLT
Rey auditory verbal learning test
(n = 3) n°1,4,30
 
Recall
(n = 2) n°46,49
WMS
Wechsler Memory Scale
(n = 2) n°9,30
Visual-spatial
BVRT
Benton Visual Retention Test
(n = 1) n°9
CPM
Raven’s coloured progressive matrices
(n = 2) n°19,46
JLO
Benton Judgement Line Orientation
(n = 4) n°4,25,43,46
 
Orientation
(n = 1) n°53
PARR
Picture Arrangement subtest
(n = 1) n°9
ROCF
Rey-Osterrieth Complex Figure test recall
(n = 1) n°11
 
Visual attention
(n = 1) n°19
 
Unknown
(n = 1) n°15
Psychiatric symptoms (n = 38)
 
Depression / Anxiety
AS
Apathy Evaluation Scale
(n = 3) n°4,32,33
BAI
Beck Anxiety Inventory
(n = 4) n°18,30,33,44
BDI
Beck Depression Inventory
(n = 9) n°5,11,18,26,30,32,33,36,44
CESD-10
Center for Epidemiological Studies Depression Scale
(n = 3) n°24,39,47
GDS
Geriatric Depression Screening scale
(n = 17) n°1,3,4,5,7,8,10,14,20,25,26,28,34,40,43,48,50
HAM-A
Hamilton Anxiety Rating Scale
(n = 2) n°33,40
HDRS
Hamilton Depression Rating Scale
(n = 3) n°4,15,33
Leeds
Leeds anxiety and depression scale
(n = 1) n°38
SCID
Structured Clinical Interview - Depression
(n = 2) n°28,40
STAI
State Trait Anxiety Inventory
(n = 4) n°18,24,39,43
UPDRS-I
Unified Parkinson’s Disease Rating Scale - mentation behavior and mood
(n = 7) n°1,14,17,25,27,43,52
ZUNG
Zung depression scale
(n = 1) n°19
TOC
OCI-R
Obsessive-Compulsive Inventory – Revised
(n = 1) n°18
QUIP
Questionnaire for impulsive-compulsive disorders in parkinson’s disease-rating scale
(n = 2) n°40,43
YBOCS
Yale-Brown obsessive-compulsive scale
(n = 1) n°33
Other
CoNeg
composite negative score
(n = 1) n°29
MMPI
Multiphasic Personality Inventory
(n = 1) n°29
NPI
NeuroPsychiatric Inventory questionnaire
(n = 3) n°1,34,47
QABB
Questionnaire About Buying Behaviour
(n = 1) n°40
Rush
Rush Hallucination Inventory
(n = 1) n°21
SCS
Sexual Compulsivity Scale
(n = 1) n°40
YMRS
Young Mania Rating Scale
(n = 1) n°33
 
Unknown
(n = 4) n°6,15,46,49
Activities of daily living (n = 22)
 
ACS
Activity Card Sort
(n = 1) n°20
ADCS-ADL
Alzheimer’s Disease Cooperative Study ADL Inventory
(n = 1) n°25
IADL
Katz Instrumental Activity of Daily Living
(n = 2) n°46,47
S&E
Schwab & England activities of daily living scale
(n = 10) n°5,14,18,26,34,38,41,43,44,53
UPDRS-II
Unified Parkinson’s Disease Rating Scale - self-evaluation of the activities of daily living
(n = 9) n°1,5,11,14,26,27,40,43,52
 
Unknown
(n = 3) n°15,17,51
Sleep quality (n = 11)
  
Actigraphy
(n = 1) n°47
ESS
Epworth Sleepiness Scale
(n = 4) n°5,14,38,43
FSS
Fatigue Severity Scale
(n = 1) n°40
ISI
Insomnia Severity Index
(n = 1) n°40
MSQ
Mayo clinic Sleep Questionnaire
(n = 2) n°4,30
PDSS
Parkinson’s disease sleep scale
(n = 1) n°40
PSQI
Pittsburg Sleep Quality Index
(n = 2) n°21,40
RBDSQ
REM Sleep Behaviour Disorder Screening Questionnaire
(n = 2) n°38,43
SA-SDQ
Sleep Apnea Scale of Sleep Disorders Questionnaire
(n = 1) n°40
SSS
Stanford Sleepiness Scale
(n = 1) n°40
 
Unknown
(n = 2) n°15,24
Quality of life (n = 9)
 
EQ-5D
Euro Quality of Life 5 Dimension questionnaire
(n = 2) n°14,38
Neuro-QOL
Quality of Life in Neurological Disorders
(n = 1) n°34
NHP
Nottingham Health Profile
(n = 1) n°20
PDQUALIF
Parkinson’s Disease Quality of Life Scale
(n = 3) n°14,18,40
PDQ-39
39-item Parkinson’s disease quality of life
(n = 5) n°7,10,20,35,40
PIMS
Parkinson’s Impact Scale
(n = 1) n°40
SF-12
The 12 item Short Form health survey
(n = 2) n°14,20
SF-36
The 36 item Short Form health survey
(n = 1) n°40
SWAL-QOL
Swallow-specific quality of life
(n = 1) n°40
Autonomic symptoms (n = 7)
  
Bowel movement
(n = 1) n°24
COMPASS
Composite autonomic symptom Scale
(n = 1) n°40
SCOPA-AUT
Scales for outcomes of Parkinson’s Disease – autonomic symptoms
(n = 3) n°4,5,43
 
Unknown
(n = 2) n°15,30
Other (n = 20)
Olfaction
Brief-SIT
Brief Smell Identification Test
(n = 2) n°24,47
 
16-item sniffin’ Sticks Odour Identification test
(n = 1) n°38
UPSIT
University of Pennsylvania Smell Identification Test
(n = 6) n°1,4,5,34,39,43
Restless legs syndrome
CH-RLSQ
Cambridge-Hopkins Restless Legs Syndrome Diagnostic Questionnaire
(n = 1) n°40
IRLSSG
Instrument for the Assessment of Restless Legs Syndrome Severity
(n = 1) n°4
Caregiver
CSI
caregiver strain index
(n = 1) n°35
 
deJong-Gierveld Loneliness Scale
(n = 1) n°47
MCSI
Multidimensional Caregiver Strain Index
(n = 1) n°35
 
Caregiver interview
(n = 1) n°21
Other
 
Agonal state questionnaire
(n = 1) n°51
CGI
Clinical Global Impression scale
(n = 1) n°38
CIRS
Chronic Illness Resource Survey
(n = 1) n°20
GHS
Global Health Score
(n = 1) n°8
GIS
Global Impression Scale
(n = 1) n°51
Howard-Dohlman device
(n = 1) n°48
MNA
Mini Nutritional Assessment
(n = 1) n°40
MOS
Medical outcome study
(n = 1) n°20
MSSSS
Medical Outcomes Study Social Support Scale
(n = 1) n°28
Pain
(n = 1) n°40
PASE
Physical Activity Scale for the Elderly
(n = 3) n°7,10,43
SRRS
Social Readjustment Rating scale
(n = 1) n°28
SSCI
Stigma Scale for Chronic Illness
(n = 1) n°20
Tremor rating
(n = 1) n°4
Visual acuity
(n = 1) n°48
Unknown
(n = 1) n°15
Most sources assessed motor and neurological functions (87%), cognition (77%) and psychiatric symptoms (72%). Activity level (42%), sleep quality (21%), quality of life (17%) and autonomic symptoms (13%) were reported to a lesser extent. The most commonly measurements used to assess motor and neurological symptoms were the Unified Parkinson’s Disease Rating Scale part III (UPDRS-III, 77% of included data sources) and the Hoehn and Yahr scale (H&Y, 57% of included data sources)(Table 4). To evaluate the cognitive impairment, the Mini Mental State Examination (MMSE, 57%) was the most frequent. Those most frequently used to assess psychiatric symptoms were the Geriatric Depression Scale (GDS, 32%) and Beck Depression Inventory (BDI, 15%). For the other dimensions, the most commonly used measurements were: the Epworth Sleepiness Scale (ESS, 8%, for sleep), the Schwab and England (S&E, 19%, for activities of daily living), the 39-item Parkinson’s disease Quality of life (PDQ-39, 9%, for the quality of life) and the autonomic part of the Scales for outcomes of Parkinson’s disease (SCOPA-AUT, 6%, for autonomic symptoms). In absolute frequency, the use of ESS, PDQ-39 and SCOPA-AUT is very low, even if they were the most frequently used measurements in their dimension.
The analysis reveals some interesting differences between sources on the number of measurements applied by dimension. Some sources evaluate only one dimension (source n°13) when others evaluate seven dimensions (source n°43). Completed sources have more frequent measurements of motor and neurological symptoms (92% vs 75%), psychiatric symptoms (76% vs 63%) and activities of daily living (43% vs 38%) than ongoing sources. US sources evaluate more frequently the cognitive impairment then international sources (86% vs 45%) but less frequently all the other dimensions. “Generic” sources evaluate three dimensions more frequently than specific sources including only Parkinsonian patients: cognition (86% vs 68%), sleep (32% vs 8%) and autonomic symptoms (25% vs 0%).
Lastly, the frequencies of these assessments are dependent on the primary objective of the sources but with an important overlap: 100% of the sources investigating motor symptoms used measurements of motor symptoms and mainly the UPDRS-III, but they also frequently assessed cognition (88%), sleep (25%) and quality of life (25%). The sources investigating non-motor symptoms frequently assessed cognition (82%), psychiatric symptoms (88%) most of the time with, respectively, the GDS (41%) and the MMSE (65%). The two genetic sources have several patient reported outcomes and they both measured motor and psychiatric symptoms.
Some measurements were used more often for some above-mentioned objectives. While the GDS and the UPDRS-III were used specifically in sources investigating, respectively, the non-motor symptoms and the motor symptoms as a primary objective, the BDI and the H&Y were used in sources investigating the other objectives.

Discussion

A large number of longitudinal real world data sources for PD have been identified. There is no consistency of the dimensions assessed, nor of the measurements used across sources, reflecting the absence of harmonization on the optimal choice of measurements.
There are a number of issues with collecting real world data such as limited size of the databases [1], inability to accurately determine specific outcomes [62], and more chance of bias and confounding factors [5]. Nevertheless, they have an important role to play in the evaluation of epidemiology, burden of disease and treatments patterns [6]; and in assisting health-care decision-makers, especially related to coverage and payment decisions [63]. In this context, a harmonization seems necessary. These results are quite consistent with those observed in Europe where a “consensus on domains incorporated in different studies [was observed] with a substantial variability in the choice of the evaluation method” [4]. There are a number of possible explanations for this absence of harmonization and some of them are discussed here.
First of all, some dimensions are broad. In consequence many measurements are available according to each source objective, design and population. This heterogeneity probably reflects both the absence of harmonization and the complexity of the evaluation of a dimension like cognition [64]. A single measurement cannot assess all necessary information. For example, the combination of patient reported outcomes and medical reported outcomes can be very informative and complement one another. In a consistent manner, the combination of Parkinson specific and generic measurements can be a necessity especially for “generic” data sources including not only Parkinsonian patients. In another example, while the objectives of the UPDRS-III and the H&Y (or of the GDS and the BDI) are close, the difference of their use according to the study primary objective of the source seems more linked to the investigator choice than to the suitability of the measurement.
Secondly, PD is characterized by several initial system disorders and treatment complications [65]. To date, motor subtyping has dominated the landscape of PD research but non-motor dimensions evaluations are increasing [9, 66], and thus the number of dimensions to evaluate. For non-motor dimensions, some have validated measurements such as psychiatry [67], activity disability [7], sleep [68] or quality of life [69]; but others have no clear review of validated and used scales [4]. Among the psychiatric scales, the two most frequently used were the GDS and the BDI. This finding highlights the well-known relationship between PD and depression, and the fact that when validated scales [70] are available, a harmonization of practice is observed. The lack of evaluation and validation of the measurements in PD is probably partly a source of such an heterogeneity.
Thirdly, clinical research purposes and outcomes are in permanent evolution over time [71, 72], as highlighted by the many differences between completed and ongoing sources. New trends are not well covered right now, either due to lack of measurements or due to lack of capture (i.e. utilization of available measurements in databases). Among the most important of those are the genetic testing, the caregiver burden and the costs. The important development of genetic testing has come in the last few years, with an increase of the mutations and treatment discoveries such as LRRK2 and its kinase inhibitors. But research is necessary to understand the role of genetic mutations in PD [73]. Sources based on caregiver burden and relevant validated measurements are very limited [7]. But the interest for these data is growing with the recognition of their physical, emotional and economic burden [74]. The only data source identified as measuring healthcare costs associated with PD was ongoing. It probably reflects both the recent growing interest of health economic evaluation and the fact that this type of study is more often conducted in automated healthcare databases [75].
Fourthly, there is a possible improvement of the access to the data source details. Given information is fragmented between different sources of information and study protocols or outcomes lists are not always available. In consequence identifying and gathering this information to produce an integrated view can be really difficult.
Finally, the variability of our results is greater than in the European study. This may be because the classification is based on dimensions assessing mostly symptoms, 5 out of 8 dimensions. This classification probably more appropriate for data sources with a primary objective of treatment evaluation (e.g. open-label extension), which are a minority of the included sources. The classification may not be as applicable to assess other data sources focused on the evaluation of burden. Real world evidence collection is done for various purposes and such a restricted classification can lead to ambiguous conclusions. It can lead to a perception of consensus while actually missing important aspects such as burden, function or complications of treatments.
Our study has several limitations. First of all, only one reader has conducted the record selection and the data extraction unlike systematic reviews. Nevertheless, the search methods identified a large number of PD data sources for extraction and comparison. No contact was established with investigators of the included studies to confirm data extraction results. To address this issue, a second step has been performed after the data extraction from the publications, to update and complete the published information with all other available sources. At risk/prodromal cohorts have not been separated from clinical PD cohorts, but the distinction between these two subgroups has recently been described as artificial [4].
Our study has several strengths. It is the first review of existing real world longitudinal data sources on PD in USA to our knowledge. Moreover, it was performed with broad research criteria and without any limitation on language, type of publication or type of measurements. This review creates an integrated view and should assist investigators and clinicians to identify and optimize the measurements that best match with their objectives and the already existing data sources.

Conclusion

In conclusion, many longitudinal real world data sources on PD exist. Different types of measurements have been used over time. To allow comparison and pooling of these multiple data sources, it will be essential to harmonize practices in terms of types of measurements.

Acknowledgements

Highly appreciated is also the support of Sandrine Thoreau for assisting with the search strategy.

Funding

The study was funded by Lundbeck SAS. The funding source, beyond the employees involved as authors, did not participate in the design of the study; collection, analysis nor interpretation of the data; nor the writing of the manuscript.

Availability of data and materials

Not applicable.
Not applicable.
Not applicable.

Competing interests

LJ is a current employee and AT was a resident in Lundbeck SAS and LI was an employee of Lundbeck SAS at the time the research was carried out.

Publisher’s Note

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Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://​creativecommons.​org/​licenses/​by/​4.​0/​), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://​creativecommons.​org/​publicdomain/​zero/​1.​0/​) applies to the data made available in this article, unless otherwise stated.
Anhänge

Appendix 1

Search strategy.
Equation 1: Disease selection
(EMB.EXACT(“Parkinson disease”) OR MESH.EXACT(“Parkinson Disease”) OR ab(“Parkinson*”)
OR ti(“Parkinson*”) OR EMB.EXACT(“antiparkinson agent”) OR MESH.EXACT(“Antiparkinson Agents”)) AND (human(yes) AND human(yes)).
Equation 2: Disease exclusion
(MESH.EXACT(“Parkinson Disease, Postencephalitic”) OR MESH.EXACT(“Parkinson Disease, Secondary”) OR EMB.EXACT(“Wolff Parkinson White syndrome”) OR EMB.EXACT(“experimental parkinsonism”) OR EMB.EXACT(“parkinsonism”) OR EMB.EXACT(“MPTPinduced parkinsonism”)) AND (human(yes) AND human(yes))
Equation 3: Study type selection
((EMB.EXACT(“register”) OR EMB.EXACT(“long term care”) OR EMB.EXACT(“retrospective study”) OR EMB.EXACT(“prospective study”) OR EMB.EXACT(“cohort analysis”) OR EMB.EXACT(“clinical practice”) OR EMB.EXACT(“longitudinal study”)) OR (MESH.EXACT(“Cohort Studies”) OR MESH.EXACT(“Registries”) OR MESH.EXACT(“Longitudinal Studies”) OR MESH.EXACT(“Long-Term Care”) OR MESH.EXACT (“Retrospective Studies”) OR MESH.EXACT(“Prospective Studies”) OR MESH.EXACT(“Practice Patterns, Physicians’”))) OR (((longitudinal OR retrospective OR prospective OR cohort OR “follow up” OR observational OR naturalistic OR “cross*sectional” OR epidemio* OR database) NEAR/1 (study OR studies)) OR “cohort analysis” OR “registry” OR “register*” OR “real-world” OR “treatment pattern*” OR “survey*” OR “medical records” OR “population-correlation” OR “population-based” OR “population-level”)
Equation 4: Study type exclusion
((MESH.EXACT(“Case-Control Studies”) OR MESH.EXACT(“Controlled Before-After Studies”) OR.
MESH.EXACT(“Feasibility Studies”) OR MESH.EXACT(“Clinical Trial”) OR MESH.EXACT(“Organizational Case Studies”) OR MESH.EXACT(“Evaluation Studies”)) OR (EMB.EXACT (“major clinical study”) OR EMB.EXACT(“in vivo study”) OR EMB.EXACT(“evaluation study”) OR EMB.EXACT(“in vitro study”) OR EMB.EXACT(“first in human study”) OR EMB.EXACT(“experimental study”) OR EMB.EXACT(“case study”) OR EMB.EXACT(“clinical study”) OR EMB.EXACT(“intervention study”) OR EMB.EXACT(“case control study”))).
Equation 5: Combination of the previous equation
(Equation 1 NOT Eq. 2) AND (Eq. 3 NOT Eq. 4)
Equation 6: Country selection
GI(“United States*”) OR ti(“America*”) OR ab(“America *”) OR ab(“usa”) OR ti(“usa”) OR ab(“us”) OR ti(“us”) OR ab(“u.s”) OR ti(“u.s”).
Equation 7: Application of the combination equation to the country of interest
Equation 6 AND Eq. 6

Appendix 2

List of outcomes extracted.
Acronym
○Full name
○Country (−ies)
○Database size (total number of patients and number of Parkinsonian patients)
○Database type
○Name of investigator (corresponding author of the publication, reference person)
○Funder(s)
○Medical imaging
○Scales list
○Scales dimension 1: Activities of daily living
○Scales dimension 2: Cognition
○Scales dimension 3: Motor or neurologic symptoms
○Scales dimension 4: Psychiatric symptoms
○Scales dimension 5: Sleep quality
○Scales dimension 6: Quality of life
○Scales dimension 7: Autonomic symptoms
○Scales dimension 8: Other
○Healthcare costs
○Genetics
○Comorbidities
○Current medications
○Severity of disease
○Caregiver burden
○Date of beginning of the study
○Date of end of the study
○Duration of follow-up
○Planned follow-ups
○Particular inclusion criteria
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Metadaten
Titel
Inventory of real world data sources in Parkinson’s disease
verfasst von
Audrey Tanguy
Linus Jönsson
Lianna Ishihara
Publikationsdatum
01.12.2017
Verlag
BioMed Central
Erschienen in
BMC Neurology / Ausgabe 1/2017
Elektronische ISSN: 1471-2377
DOI
https://doi.org/10.1186/s12883-017-0985-0

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