Drug-based pain management for people with dementia after hip or pelvic fractures: a systematic review

The search was performed according to the protocol, and studies were included that investigated drug-based pain management for PwD following hip or pelvic fractures in all settings and which were published up to January 2016. MEDLINE, EMBASE, CINAHL, Web of Knowledge and ScienceDirect were searched. The search strategy was set up using the database-specific vocabularies (MeSH, EMTREE), additional free text terms and Boolean operators (AND, OR). Included search terms were, for example, “analgesia”, “dementia”, “cognitive impairment”, “pain treatment”, “hip fracture” or “pelvic fracture”. Study selection was performed independently by two reviewers who screened the titles and abstracts. The selected full texts were also double-checked for inclusion. Backward citation tracking and forward citation tracking were performed. The complete search strategy can be found in the systematic review protocol [16].

Titles and abstracts had to be in English or German. Studies were included that investigated drug-based pain management for people with dementia in cases of hip or pelvic fracture which were treated either by operation or conservatively, regardless of the setting. Original qualitative, quantitative or mixed-methods studies and also grey literature were included. Letters, short reports and abstracts were screened in order to identify further original studies. Publications without available references were excluded. The inclusion criteria were pre-tested with a set of 100 articles. Studies with a high level of bias were finally excluded after critical appraisal.

Data was extracted to gain an overview of the studies’ contents, i.e., study design, settings and study findings. Further, we extracted data collection methods, outcomes measures, type of data, e.g. databases on administrative or clinical data etc., regarding the applied assessments of mental status, pain and drugs in the identified studies. A content analysis was conducted deductively with predefined categories: e.g. author, date, study type, study designs, mental tests, pain scales, findings and the result of the critical appraisal of the study quality. In order to describe the pain management and the applied assessments, further categories were developed inductively by identifying the relevant aspects of the studies, e.g. categorisation of drugs in the studies, assessment of the administered drugs.

A critical appraisal was performed by two reviewers independently for each type of study by using specific appraisal tools and the checklists of the Scottish Intercollegiate Guideline Networks (SIGN) [17]. Studies that were not covered by the SIGN guidelines were evaluated, using the tools of the National Institute for Health and Care Excellence (NICE) for cross-sectional studies [18]; tools from the Joanna Briggs Institute for Case Series [19] and tools developed by Greenhalgh et al. [20] were applied for questionnaire surveys.

Out of the 22 full texts selected, five with considerable methodological flaws were excluded: for example, if the inclusion criteria were unclear [13], or if no confounders were considered and the outcomes were not clearly defined [30]. The eight included cohort studies with a lower number of bias met six to nine of the 14 quality criteria of the SIGN checklist. It is to be taken into account that in the study by Jensen-Dahm et al. [22], which met six quality criteria, five of the items were “not applicable” in terms of the critical appraisal. Three of the four cross-sectional studies met 11 quality criteria [28, 31, 32], while the study by Holdgate et al. [27] met 10 of the 17 quality criteria of the NICE checklist. The case study by Ardery et al. [21] met seven out of the ten quality criteria of the Joanna Briggs Institute’s checklist. Three of the four healthcare professionals’ surveys studies by Rantala met eight of the 13 quality criteria of Greenhalgh’s checklist [14, 24, 25]. The study by Rantala and Hartikainnen [23, 25] met four points since some facts were not reported. However, they were reported in a similar study by the authors a year later [24]. A more detailed look at the critical-appraisal results can be found in Table 3.

Eight of the 13 studies focusing on patient data showed that PwD received less drug-based pain management than people without cognitive impairment. Seven of the eight studies found the differences to be statistically significant, and one study found no significant differences but did note a tendency [33]. These eight studies are as follows: Adunsky et al. [10] stated that PwD received only 53% of the amount of opioid analgesics that were administered to cognitively intact patients (P < 0.001); Feldt et al. [33] came to the conclusion that, even though the prescription of pain medication did not differ significantly, PwD received fewer opioid analgesics (P = 0.02 in the first and P = 0.07 in the second 48 h post-operatively); Grall [34] pointed out that people without dementia received almost 50% more pain medication compared to their counterparts with dementia following acute hip fracture (p = 0.018); Jensen-Dahm et al. [22] came to the result that PwD received lower doses of oral morphine equivalents during the first (P = 0.001) and second postoperative day (P = 0.019), lower doses of acetaminophen during the first 3 days post-operatively (P < 0.0001), and were also more likely to receive opioids pro re nata (PRN) (P = 0.0005); the study by McDermott et al. [26] outlined that PwD received a weaker level of analgesia both in the outpatient and in the emergency setting (P < 0.001); Morrison and Siu [12] found that the advanced dementia patients in their study received one-third of the amount of morphine sulphate equivalents that the cognitively intact patients did (P < 0.02), and that 76% of the PwD did not have a standing order for their analgesic agent for their entire hospitalisation (P = 0.44); in the study by Mak et al. [31]. PwD used distinctly less analgesia during all the time periods measured (P < 0.001) and Titler et al. [32] concluded that PwD received significantly fewer mean parenteral morphine equivalents of opioids than those without dementia (P < 0.001).

There were five studies that did not identify undertreatment of pain for PwD: Ardery et al. [21] did not find a correlation between cognitive status and patterns of analgesic administration; Feldt et al. [35] found no differences between PwD and those without cognitive impairment in the amounts of opioid analgesics and acetaminophen prescribed or administered in the first or second 48 h post-operatively; and Feldt and Gunderson [29] stated that the setting was the only relevant factor relating to drug-based pain management, arguing that subjects in the hospital setting received more analgesia regardless of their mental status (P = 0.025). Despite finding no undertreatment of pain, Hwang et al. [28] still came to the conclusion that dementia is a risk factor for undertreatment of pain, considerable delays in analgesic administration and inappropriate choice of drugs, while Holdgate et al. [27] stated that dementia is one of the most frequently reported barriers to providing analgesia after hip fracture.

The two studies by Rantala and Kankunnen [14, 25] based on surveys of healthcare professionals also concluded that cognitive impairment is a major barrier for effective pain management. Rantala and Hartikainen [14, 25] claimed that the pain medication, if only prescribed PRN, depends heavily on the nurses in charge. More experienced nurses had complete pain relief as the main goal of pain management more often than younger nurses with less work experience [23, 24].

An overview of clinical assessments and data describing pain management are displayed in Table 4.

A number of different tools were applied to assess the patients’ mental status. The Mini Mental State Examination (MMSE), which was performed most frequently, was used in six studies [10, 26, 29, 31, 33, 35]. Morrison and Siu [12] combined the MMSE with the Confusion Assessment Method (CAM) and the Reisberg Global Deterioration Scale to screen their patients not only for dementia but also for delirium, while Adunsky et al. [10] only combined the MMSE and the CAM.

In the study performed by Mak et al. [31] previously documented dementia and MMSE scores were used to determine the patients’ mental status. McDermott et al. [26] applied the Abbreviated Mental Test Scores (AMTS) to their patients upon arrival at the ambulance and/or emergency department. Further, three studies reviewed the charts for ICD codes for presence of dementia [22, 27, 34], among which the study by Jensen-Dahm et al. [22] also checked for prescription of anti-dementia drugs. Hwang et al. [28] used patients’ self-reports of Alzheimer’s disease or other forms of dementia in combination with physicians’ chart notes regarding mental state, while the study by Titler et al. [32] and its subsequent study by Ardery et al. [21], which worked with the same data, simply reviewed the charts for any sign of dementia. The studies focusing on healthcare professionals did not provide any information about the assessment of their patients’ mental state [14, 23‐25].

In four of the included studies focusing on patient data, no information about assessment was given [10, 22, 26, 31]. In the nine studies that actively assessed the patients’ pain there was a great heterogeneity regarding the applied tools. The three studies performed by Feldt et al. [29, 33, 35] applied Ferrel’s Pain Experience Interview (FPEI), as well as the Verbal Descriptor Scale (VDS) and the Checklist of Non-Verbal Pain Indicators (CNPI). The study by Grall [34] assessed pain on three different levels: verbal pain assessment on the Wong-Baker FACES Pain Scale (W-BFPS), non-verbal pain assessment with behavioral pain intensity scores on the Faces, Legs, Activity, Cry and Consolability Scale (FLACC) and physiological changes in heart rate and systolic blood pressure. Morrison and Siu [12] used the Verbal Rating Scale (VRS) daily, while there were four studies that reviewed the charts for all types of pain assessment, because of the heterogeneity of the pain assessments in these hospitals [21, 27, 28, 32]. Two of the studies by Rantala [14, 25], as well as the study by Titler et al. [32], included a section asking healthcare professionals how they assessed pain. The healthcare professionals reported that they apply a wide range of pain assessment tools: e.g. behavioural observation, the Visual Analog Scale (VAS), the Visual Rating Scale (VRS), the Numeric Rating Scale (NRS), verbal assessment of pain, the Facial Pain Scale and Pain Assessment in Advanced Dementia (PAINAD).

The assessment of the drugs administered was achieved through retrospective chart review in all but one of the studies working with patient data. Morrison and Siu [12] was the only study to perform a daily chart review.

Nine studies stated that they had converted the opioids administered into morphine equivalents [10, 12, 21, 22, 29, 31‐33, 35], while one study converted opioids as well as non-opioids administered into acetaminophen equivalents [34]. Four studies noted that they had adjusted their drug administration according the World Health Organization analgesic ladder [12, 23, 24, 26, 36]. The study by Holdgate et al. [27] simply documented all the drugs administered, whereas Hwang et al. [28] grouped the drugs administered into opioids and non-opioids. A more detailed look at this can be found in Table 4.