Background
Methods
Routine clinical care pathway
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PatientsPatients aged ≥70 years who are candidate for intensive treatment in cardiovascular, thoracic, orthopaedic and oncology outpatient clinics undergo geriatric screening.
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Geriatric screeningA trained nurse uses geriatric screening to identify patients with potential frailty who may be in need of further evaluation by comprehensive geriatric assessment [11]. Geriatric screening consists of the Geriatric 8 (G-8) screening questionnaire [19] and the Six-Item Cognitive Impairment Test (6CIT) [20] and takes about 5 minutes to complete. The G-8 is an eight-item questionnaire developed for older cancer patients but also used in other populations. It covers multiple domains and places significant weight on nutritional status (47% of the total score). In a review by Decoster et al. the reported sensitivity to detect a need for further evaluation by geriatric assessment was over 80% in six studies [11]. The G-8 does not actually test cognition. Cognitive impairment is generally associated with adverse health outcomes such as delirium [37], a prolonged length of hospital stay [38] and subsequent mortality [38]. The 6CIT is a brief and simple cognitive test and correlates well with the Mini-Mental State Examination (MMSE) [21]. The original cut-off score of the 6CIT is ≥11 (i.e. MMSE 24), an alternative cut-off score is > 7 [20, 21]. When using the cut-off score of > 7, the reported sensitivity is 78.6% and the specificity is 100% [21]. We chose to use the alternative cut-off score > 7 to enhance sensitivity and identify more patients with potential cognitive impairment. Patients are referred for CGA when their G-8 score is ≤14 and/or the 6CIT is > 7, or if the patient has a history of delirium or dementia (Fig. 1).
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Comprehensive geriatric assessmentIn those patients with an abnormal geriatric screening a CGA is subsequently performed in the geriatric outpatient clinic. Time scheduled for this consultation is 60–90 min. Content:
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Somatic statusThe somatic status includes information about the current diagnosis and symptoms, medical history and medication use. Weight, height, body mass index (BMI), blood pressure, heart rate and orthostatic hypotension are measured and a complete physical examination is performed when indicated. Malnutrition is associated with mortality and functional dependency in different patient populations [39]. Nutritional status is assessed using the Mini Nutritional Assessment Short Form (MNA-SF®) [23]. The MNA-SF® is the test preferred by the Inspectorate of Public Health in the Netherlands [40]. -
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Psychological statusDepressive symptoms are associated with outcomes such as mortality [41, 42] and functional decline [43]. The two-item Patient Health Questionnaire (PHQ-2) [24] is a short instrument used to screen for depression. This screening instrument is suitable since a score ≥ 3 shows a sensitivity of 83% and specificity of 92% for detecting major depression [24]. When further evaluation is needed, the Geriatric Depression Scale-15 (GDS-15) [25] is administered.Previous studies have shown an association between a higher level of optimism and a lower risk of cardiovascular events and all-cause mortality [44]. To measure optimism a three-item questionnaire is used that contains the three positively worded questions of the Life Orientation Test-Revised (LOT-R) [26].In the event of an abnormal 6CIT on geriatric screening, the Visual Association Test (VAT) [27] and the Clock Drawing Test [28] are performed to assess cognition. The VAT tests visual associative memory and the Clock Drawing Test assesses visuospatial and executive functioning. When indicated, a neurocognitive assessment including a full neuropsychological battery of tests is performed. -
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Functional statusFunctional dependency is associated with mortality in both the general population and in hospitalised patients [45]. To explore patients’ functional status, the Activities of Daily Living score (Katz ADL) [29] and Instrumental Activities of Daily Living (Lawton IADL) [30] are assessed. The 6-item Katz ADL was chosen because it is already administered to all hospitalised patients aged ≥70 years as part of a mandatory national Dutch Safety Management System (Veiligheid Management Systeem Kwetsbare ouderen, VMS) and is suitable for extended follow-up. Furthermore, we previously successfully used the Katz ADL to follow over 2600 older patients who visited the Emergency Department [46, 47]. The 8-item Lawton IADL focuses on more complex activities of daily living. The aim of these questionnaires is to assess the overall (representative) functional status and is not based on (sub)acute functional decline prior to clinical evaluation. Furthermore, a 4-m gait speed measurement and handgrip strength are performed to assess physical capacity. Slow gait speed [31, 48] and poor handgrip strength [49, 50] are associated with outcomes such as mortality, disability and cognitive decline. -
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Social statusThe patients’ social status is explored by asking about living arrangements (independent, institutionalized, hospitalised), the availability of a formal caregiver and level of support (number of days with home care). -
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Quality of lifeHealth-related quality of life is associated with mortality and functional decline in older hospitalised patients [51] and is measured using the EuroQol five dimensions questionnaire (EQ-5D-3L), including the visual analogue scale (EQ-VAS) [35]. Since the EQ-VAS is part of the outcome measures of the TENT study and is collected by telephone at follow-up, we chose to use a verbal description of the EQ-VAS and register the patients’ verbal answer on a numerical rating scale. Previous studies have shown comparable results between telephone administration of the EQ-5D and EQ-VAS and face-to-face administration [52] and patient-completed forms [53].
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Clinical decision makingDuring a multidisciplinary team meeting different treatment options are considered, including standard care, less intensive treatment options and best supportive care. Information obtained from the comprehensive geriatric assessment, the remaining life expectancy, expected effect of different forms of treatment on relevant outcomes for older patients and patient preferences are taken into account. Patient preferences are assessed by asking the patients’ perspective on possible treatment goals, e.g. prolonged survival, maintaining independence, reducing symptoms or other personal goals. Less intensive treatment is proposed when the CGA indicates frailty and hence an increased risk of functional decline. Treatment recommendations that are formulated during multidisciplinary team meetings are again discussed with the patient during the final treatment decision consult, emphasizing patient perspective and the predictive value of existing geriatric impairments on relevant outcomes. This entire process results in individualised treatment decisions.
Test | Explanation | Scores |
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Geriatric screening | ||
G-8 [19] | 8-item screening test. Assesses domains of nutritional status, mobility, neuropsychological problems, medication use, self-rated health status and age | Score ranges from 0 to 17, lower score indicates more impairment, cut-off score ≤ 14 |
6-item cognitive screening test. One memory, two attention and three orientation questions | Score ranges from 0 to 28, higher score indicates more significant cognitive impairment, cut-off score > 7 | |
Comprehensive geriatric assessment | ||
Somatic status | ||
Medical history | Polypharmacy, multi-morbidity using CCI [22]: 16 medical condition of which 3 are stratified according to severity | Score ranges from 0 to 33, higher score indicates more comorbidities |
Physical measurement | Weight, height, BMI, blood pressure, heart rate, orthostatic hypotension, complete physical examination on indication | N/A |
MNA-SF® [23] | 6-item screening test. Assesses loss of appetite, weight loss, BMI, mobility, the occurrence of stress or an acute disease and neuropsychological problems | Score ranges from 0 to 14, lower score indicates greater risk of malnutrition, cut-off score ≤ 11 |
Psychological status | ||
PHQ-2 [24] | 2-item screening test for depression | Score ranges from 0 to 6, higher score indicates more depressive symptoms, cut-off score ≥ 3 |
GDS-15 [25] | 15-item questionnaire. Assesses depressive symptoms | Score ranges from 0 to 15, higher score indicates more depressive symptoms, cut-off score ≥ 5 |
Optimism questionnaire [26] | 3-item questionnaire. Assesses optimism on a 5-point Likert scale: 0 corresponds to “strongly disagree” and 4 to “strongly agree” | Score ranges from 0 to 12, higher score indicates greater optimism |
VAT [27] | Learning task that assesses visual associative memory | Score ranges from 0 to 12, lower score indicates more cognitive impairment |
Clock drawing [28] | Cognitive test that assesses visuospatial and executive functioning | Score ranges from 0 to 14, lower score indicates more executive impairment, cut-off score < 10 |
Functional status | ||
Katz ADL [29] | 6-item questionnaire. Assesses bathing, dressing, toileting, transfers, continence and feeding | Score ranges from 0 to 6, higher score indicates greater dependency |
Lawton IADL [30] | 8-item questionnaire. Assesses more complex independent living skills: ability to use a phone, shopping, food preparation, housekeeping, laundry, mode of transportation, responsibility for personal medications, ability to handle finances | Score ranges from 0 to 8, lower score indicates greater dependency |
Timed 4-m walking test | Lower score represents slow gait speed, cut-off speed ≤0.8 m/s | |
Handgrip strength measurement, using a Jamar Handheld Dynamometer. Best of 3 measurements using the dominant hand | Reference values depend on age and gender | |
Social status | Living arrangement (independent, institutionalised, hospitalised), the availability of a caregiver, hours of (home)care | N/A |
Quality of life | ||
5-item questionnaire. Assesses health-related quality of life exploring five dimensions: mobility, self-care, daily activities, pain/complaints, mood. Three possible levels of answers: no problems, some problems, extreme problems | An index score is calculated, score ranges from − 0.33 to 1.0. Score < 0 represents worse than dead and 1 represents full health | |
Verbal description of an overall health state visual analogue scale, registered on a numerical rating scale | Score ranges from 0 to 100, higher score indicates higher health-related quality of life |
TENT study
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Study designThe TENT study is a prospective cohort study that commenced on 1st February 2016 in the aforementioned hospitals. Inclusion is still ongoing. Patients in the care pathway are asked to participate in the present study, in which we collect clinical data and additional blood samples at baseline. Participants are followed for 1 year.
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ParticipantsIn order to assemble a representative cohort it is important that all patients in the clinical care pathway actually participate, including those patients without signs of frailty during geriatric screening. Consequently, all patients are invited to participate in the TENT study and are subsequently assessed for eligibility based on the criteria aged ≥70 years and candidate for intensive treatment, including surgery, chemotherapy, (chemo-)radiation therapy, immunotherapy or other cancer therapies. Participants who are not able to understand the Dutch language, or are not able to provide informed consent and have no proxy available, are excluded.When geriatric screening indicates potential frailty, the patient is referred to the geriatric outpatient clinic for comprehensive geriatric assessment and invited to participate. Patients without signs of frailty during geriatric screening are contacted by telephone for inclusion. The Medical Ethics Committee of the LUMC issued a ‘certificate of no objection’ for retrospective data collection of patients with the same diagnosis not included in the TENT study. This means we will be able to determine whether included patients are representative of the overall patient population in terms of baseline characteristics, treatment administered, and selected outcomes (mortality, treatment complications).
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Data collection
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BaselineThe following data are collected from the digital patient files: medical history, medication use, smoking and alcohol status and history, level of education, multi-morbidity using the Charlson Comorbidity Index (CCI) [22], diagnosis that indicated intensive treatment, treatment choice, laboratory tests, geriatric screening, comprehensive geriatric assessment and in case of a malignancy, WHO performance status, tumour characteristics and stage. When a participant is not referred to the geriatric outpatient clinic, a short geriatric assessment is administered by telephone by a research nurse or researcher. This geriatric assessment includes psychological status (PHQ-2, optimism questionnaire), functional status (Katz ADL, Lawton IADL), social status and quality of life (EQ-5D-3L and EQ-VAS). Physical capacity tests are not performed. -
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Follow-upParticipants are contacted by telephone for follow-up at 6 and 12 months after the start of treatment. The following data are collected: Katz ADL, Lawton IADL, EQ-5D-3L and EQ-VAS, and social status. In case a participant is not able to answer the questions, a proxy is allowed to answer all questions except the EQ-VAS. The proxy is registered as contact in the digital patient file, or another caregiver involved in daily care is asked. -
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BiomaterialAt baseline blood samples are collected to study biomarkers of ageing. These samples consist of two gel tubes (8.5 cc), one tube of EDTA plasma (10 cc), and one sodium citrate tube (4.5 ml). We plan to use several methods to measure biological ageing, including algorithms that are based on routinely collected blood chemistry data, measurement of metabolomics, and epigenetics [54]. -
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Data managementData are recorded on Case Record Forms, encrypted and stored in an electronic data management system (Castor EDC [55]), in accordance to General Data Protection Regulations (GDPR).
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OutcomesThe primary outcome is the composite endpoint of functional decline or mortality at 1 year. Data on the following endpoints are currently being collected:
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All-cause mortality, by consulting municipal registries (in Dutch: Basisregistratie Personen). -
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Functional status at 6 and 12 months after treatment initiation. Functional improvement is defined as an at least one-point decrease in Katz ADL compared to baseline. Functional decline is defined as at least one-point increase in Katz ADL compared to baseline or a new institutionalization. -
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Change in quality of life between baseline and 6 and 12 months follow-up based on the EQ-5D-3L index score and EQ-VAS. -
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Complications during hospital admission or treatment, such as infections, delirium, re-operation, grade 3–5 toxicity of chemotherapy, radiation therapy or other cancer therapy, early treatment discontinuation, or adjustment of treatment intensity. This information is obtained from digital patient files. -
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Total length of hospital stay, defined as the number of days between hospital admission for intensive treatment (surgery) and discharge. This information is obtained from digital patient files. -
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Unplanned admission to an intensive care unit. This information is obtained from digital patient files. -
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Unplanned hospital admission. This information is obtained from digital patient files.
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Statistical analysisStatistical analysis will be performed using SPSS software version 25 or STATA version 14. Determinants and endpoints will be tabulated to gain insight into data and regression models (Cox regression, linear regression and linear mixed models, binary logistic regression) used to study associations between determinants of endpoints, taking into account potential confounding. Excessive testing can be avoided by formulating hypotheses before the data analysis, reducing false-positive findings. When necessary, correction for multiple testing will be applied. Moreover, to illustrate the clinical significance of associations, results will be compared to the minimal clinically important difference. Table 2 shows the minimal clinically important differences (MCID) of the Katz ADL [56], Lawton IADL [56], EQ-5D-3L [57] and EQ-VAS [57] as reported in previous studies that most closely resemble our study population.We will also transform predictive values from the multivariate models into individual risk scores, predicting the selected endpoint using Receiver Operating Curves (ROC) and their area under the curve (AUC, also called c-statistic). Sensitivity, specificity, positive and negative predictive power will also be assessed. Several techniques are available to evaluate models. We intend to use bootstrapping methods for internal validation.
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Sample size calculationThe number of participants differs per disease, but we aim to have sufficient power to predict adverse health outcomes in the various groups. We will carry out a formal power calculation per research question depending on the disease, determinant and outcome studied. An example of a sample size calculation is provided for a prediction model with the composite outcome of functional decline or 1-year mortality. Functional decline is defined as an at least one point increase in Katz ADL score or new institutionalization at 1-year follow-up. To reduce the risk of false positive findings (predictors) the so-called ‘EPV (events per variable) 1 to 10 rule of thumb’ is often applied. This rule suggests that at least 10 events per candidate predictor are needed for reliable prediction modelling [58, 59]. As we expect the model to include 8 predictors, at least 80 patients with the event of interest will be needed. When the incidence of the composite outcome in a certain patient population is 30% and the drop-out rate is 10%, the target sample size for the prediction model would be 294 patients.
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Ethics approval and consent to participateThe TENT study protocol was approved by the Medical Ethics Committee (METC) at Leiden University Medical Center. All participants or a proxy provided written informed consent.