A Study On Prescriptions Contributing To The Risk Of High Anticholinergic Burden In Adults With Intellectual Disabilities: Retrospective Record Linkage Study

doi:10.21203/rs.3.rs-1419182/v1

Background: People with intellectual disabilities face a disproportionate risk of experiencing high anticholinergic burden, and its negative sequalae, at younger ages than the general population. Our aim was to determine the source of that burden from prescribed medication.

Methods: Retrospective matched observational study using record linkage. Adults with (n=4,305), and without (n=12,915), intellectual disabilities matched by age-, sex- and neighbourhood deprivation. The main outcome measure was the prescription of long-term (approximately 9 months use) anticholinergic medications overall, by drug class, individual drugs, and polypharmacy.

Results: 38.4% and 23.6% of adults with, and without, intellectual disabilities were prescribed medications long-term with anticholinergic properties. Of those on such drugs, adults with intellectual disabilities were most likely to be on central nervous system (62.6%), gastrointestinal (46.7%), and cardiovascular (28.4%) medications. They were prescribed more central nervous system, gynaecological/urinary tract, musculoskeletal, and respiratory medications, and less cardiovascular, infection, and endocrine medications than their matched comparators. Regardless of age, sex, or neighbourhood deprivation, adults with intellectual disabilities had greater odds of being prescribed antipsychotics (OR=5.37 [4.40-6.57], p<0.001), antiepileptics (OR=2.57 [2.22-2.99], p<0.001), and anxiolytics/hypnotics (OR=1.28 [1.06-1.56], p=0.012). Adults with intellectual disabilities were more likely to be exposed to overall anticholinergic polypharmacy (61.3% (n=1,013), 54.7% (n=1,668) respectively, OR=1.48 [1.33-1.66], p<0.001), and to psychotropic polypharmacy than adults without intellectual disabilities (33.7% (n=558), 14.3% (n=435) respectively, OR=2.79 [2.41-3.23], p<0.001).

Conclusions: Adults with intellectual disabilities are exposed to a greater risk of having very high anticholinergic burden through polypharmacy from several classes of medications, which may be prescribed by several different prescribers. Clinicians need to be cognisant of this issue, and the potential adverse consequences. These findings highlight the need for regular medication reviews to reduce inappropriate prescribing and adverse anticholinergic effects.

intellectual disabilities

anticholinergic burden

polypharmacy

psychotropics

Adults with intellectual disabilities experience an increased risk of adverse effects associated with high anticholinergic burden.^1–4 Previous literature has focused predominantly on the older adult general population and found high anticholinergic burden to be associated with a range of poor health outcomes including cognitive impairment and dementia;⁵ emergency health service use,⁶ and all-cause mortality.^7–9 Common adverse effects of anticholinergic burden include constipation, dry mouth, blurred vision, cognitive impairment, urinary retention, dry mouth, and increased fall risk. Some recent studies have also included younger adults. A UK Biobank study investigating 502,538 adults found high anticholinergic burden in 27–73 year olds was modestly associated with cardiovascular events, hospital admissions (due to fall/fractures, and dementia/delirium) and mortality.⁹ The cumulative impact of anticholinergic burden is therefore a pertinent issue in the pharmacotherapy of all patients across the lifespan.

People with intellectual disabilities have poorer health than the general population, and often have long-term health problems. Higher multimorbidity and more complex health needs occur at younger ages and continue throughout the lifespan, with poorer health outcomes and premature mortality.¹⁰ Subsequently, people with intellectual disabilities are more likely to experience polypharmacy (taking multiple medication concomitantly, e.g. 5+) with complex pharmacotherapy that can result in a significantly increased risk of adverse effects associated with anticholinergic burden. Prescriptions may be issued by several separate medical specialties for the same person, contributing to total anticholinergic burden. Whilst some increased medication use is appropriate, given the higher prevalence of physical and mental ill-health, there are an increasing number of guidelines and initiatives aimed at reducing inappropriate prescribing, considering medication review and de-prescribing where appropriate.^11–13 Previous evidence has indicated psychotropics to be the main drug class responsible for high anticholinergic burden in older adults with intellectual disabilities (aged 40+).³ Within this class of medications, a large focus of attention has been on the off-label use of antipsychotics to manage ‘challenging behaviour’ in this population.¹⁴ This is despite high anticholinergic risk, lack of substantial evidence base of effectiveness in this context, and no clear indication for antipsychotic use. ¹⁴ If there is no diagnosis of mental ill-health, best practice guidelines recommend short-term use only with review of efficacy after 3–4 weeks,¹² and as part of a multimodal treatment approach, i.e. non-pharmacological psychosocial or behavioural interventions.¹⁵

This paper reports on the contribution of different classes of drugs to the risk of high anticholinergic burden in adults with intellectual disabilities compared to those in the general population, and also investigates psychotropic prescriptions in further detail.

Study Cohort

The research was approved by Scotland’s Public Benefit and Privacy Panel for Health and Social Care (reference 1516 − 0281). The NHS Greater Glasgow and Clyde Primary Care Intellectual Disabilities Register of 2014 was created from multiple sources (e.g. General practitioners who were financially incentivised to identify all their patients with intellectual disabilities (100% did so) and community intellectual disabilities teams) and updated annually thereafter. It was used to identify all adults (aged 17+) with intellectual disabilities within the defined geographical boundary of NHS Greater Glasgow and Clyde, which forms almost a quarter of the Scottish population. Adults with intellectual disabilities were each matched to three general population adults based on age (year of birth), sex, and neighbourhood deprivation (Scottish Index of Multiple Deprivation: SIMD2016 using the postcode area). In Scotland, patient health records are identified using their unique patient identifier; the Community Health Index (CHI), which is held centrally by National Services Scotland (NSS). The CHI database was used for this matching and linkage process. NSS also holds the Prescribing Information System database, which was used to identify 1 year of anticholinergic medication prescriptions between September 2016 and August 2017 for the study groups. This data source records all community prescribed and dispensed medications in Scotland and classifies them via British National Formulary categories. NHS Scotland’s Information Services Division completed data linkage and extraction in August 2017. The study group consisted of 17,228 but during data cleaning the research team identified two general population adults as having intellectual disabilities. Since each adult with intellectual disabilities was matched with general population adults 1:3 to create one ‘cluster’, all participants from these matched clusters were excluded (n = 8), leaving a sample size of n = 17,220. Further details on sampling and linkage have previously been reported.⁴

Anticholinergic medications were identified using the modified Anticholinergic Risk Scale (ARS) which was updated by the authors.⁴ The ARS list classifies anticholinergic medicines as moderate (risk category 1), strong (risk category 2), and very strong (risk category 3), and is one of the more conservative anticholinergic burden scales. There are numerous anticholinergic burden scales, although there is consensus of a cumulative total score of 3 or greater to be clinically at risk of adverse effects. To determine the main contributors to anticholinergic burden, prescriptions were included if there were 3 or more repeat prescriptions constituting approximately 9–12 months usage during the year being studied. Anticholinergic drugs were those listed in the updated ARS and categorised according to the British National Formulary (BNF) chapter, and psychotropic sub-chapters.

Statistical Analysis

Data were summarised descriptively by group (those with, and without intellectual disabilities), for each medication outcome. Outcomes investigated were individual medication classes, psychotropic prescribing (antipsychotics, antiepileptics, antidepressants, anxiolytics/hypnotics) and polypharmacy. Group comparisons were made using mixed-effects binary logistic regression models with a fixed effect for group, and a random effect for the matched cluster. Group effects are reported from models adjusted for known confounders (sex, age category, SIMD quintile), with the general population as reference and intellectual disabilities cohort as effect level.

Interaction terms between group and each main effect (sex, age, SIMD quintile) were added to adjusted models and when significant, explored using both odds ratios (OR) and marginal effects at representative values (MERs). OR [95% Confidence Intervals] and p-values are reported for the adjusted group effect tested within each level of the main effect, e.g. significant interaction between group (adults with and without intellectual disabilities) and age examined by modelling the group effects within each age category. Using the full model (main effects and interaction term), the MER analyses shows the magnitude of effects allowing us to obtain predicted probabilities of the group effect on each outcome. Adjusted MERs describe the strength of an association between a risk factor (e.g. group) and the outcome (e.g. antipsychotic use), allowing us to see how the marginal effect differs across that range (e.g. change across age categories), at representative values of covariates (held constant),¹⁶ e.g. the predicted probability of being on an antipsychotic if an adult is in the intellectual disabilities group and aged 55–64 (within group analysis). Values were chosen on the basis of no statistically significant effects of that covariate in the group interaction term (e.g. average of sex and SIMD for group differences in antipsychotic prescribing). Statistical analyses were conducted in Stata (StataCorp 2017).

Demographics

The full dataset included n = 4,305 adults with intellectual disabilities and n = 12,915 general population adults. General demographics for this full sample can be seen in Table 1. Of the full sample, there were 1,654 (38.4%) adults with intellectual disabilities prescribed anticholinergic medication, compared to 3,047 (23.6%) adults without intellectual disabilities. These groups comprise our population for all analyses (Table 1).

Table 1

Descriptive statistics for total sample and subgroup of those taking long-term anticholinergic medications (≥ 3 repeat prescriptions).
Characteristic	Total		AC medications
Characteristic	ID	GPop	ID	GPop
Population	4,305	12,915	1,654	3,047
Sex
Male	2,504 (58.2%)	7,512 (58.2%)	925 (55.9%)	1,628 (53.4%)
Female	1,801 (41.8%)	5,403 (41.8%)	729 (44.1%)	1,419 (46.6%)
Age categories
17–24	403 (9.4%)	1,209 (9.4%)	96 (5.8%)	38 (1.3%)
25–34	811 (18.8%)	2,433 (18.8%)	224 (13.5%)	172 (5.6%)
35–44	673 (15.6%)	2,019 (15.6%)	210 (12.7%)	282 (9.3%)
45–54	965 (22.4%)	2,895 (22.4%)	418 (25.3%)	726 (23.8%)
55–64	794 (18.4%)	2,382 (18.4%)	366 (22.1%)	859 (28.2%)
65–74	464 (10.8%)	1,392 (10.8%)	235 (14.2%)	645 (21.2%)
75+	195 (4.5%)	585 (4.5%)	105 (6.4%)	325 (10.7%)
SIMD
1-most deprived	2,293 (53.3%)	6,879 (53.3%)	867 (52.4%)	1,821 (59.8%)
2	848 (19.7%)	2,544 (19.7%)	331 (20.0%)	605 (19.9%)
3	545 (12.7%)	1,635 (12.7%)	233 (14.1%)	335 (11.0%)
4	349 (8.1%)	1,047 (8.1%)	135 (8.2%)	173 (5.7%)
5-least deprived	270 (6.3%)	810 (6.3%)	88 (5.3%)	113 (3.7%)
AC = anticholinergic, GPop = General Population, ID = Intellectual Disabilities

Anticholinergic drugs across medication classes

For the adults with intellectual disabilities prescribed medications with anticholinergic effects, these were most likely to be central nervous system (62.6%), gastrointestinal (46.7%), cardiovascular (28.4%), and respiratory system medications (13.4%) (Table 2). The pattern differed for the general population (though may not be representative of the whole general population who are older, have equal sex ratio, and a different distribution of SIMD, due to the matching with the intellectual disabilities group). Compared to the matched general population, the adults with intellectual disabilities were more likely to be prescribed central nervous system (2.23 [1.96–2.53]), obstetrics, gynaecology, urinary tract (2.82 [1.83–4.34]), and musculoskeletal (2.49 [1.69–3.67]) medications and were less likely to be prescribed cardiovascular (0.61 [0.53–0.71]), infections (0.43 [0.21–0.68]), and endocrine (0.45 [0.29–0.68]) medications.

Table 2

The number and percentage of adults with intellectual disabilities prescribed anticholinergic medication by medication class (BNF chapter), in comparison to general population adults.
BNF Chapter	Adults prescribed anticholinergic medications (n = 4,701)		OR [95% CI], p-value*
BNF Chapter	Intellectual Disabilities (n = 1,654)	General Population (n = 3,047)	OR [95% CI], p-value*
Gastro-Intestinal System	773 (46.7%)	1,505 (49.4%)	1.00 [0.88–1.13], p = 0.985
Cardiovascular System	477 (28.4%)	1,419 (46.6%)	0.61 [0.53–0.71], p < 0.001
Respiratory System	222 (13.4%)	373 (12.3%)	1.06 [0.88–1.27], p = 0.547
Central Nervous System	1,037 (62.6%)	1,231 (40.4%)	2.23 [1.96–2.53], p < 0001
Infections	9 (0.54%)	53 (1.7%)	0.43 [0.21–0.86], p = 0.017
Endocrine System	29 (1.8%)	120 (3.9%)	0.45 [0.29–0.68], p < 0.001
Obstetrics, Gynaecology & Urinary-Tract Disorders	51 (3.1%)	40 (1.3%)	2.82 [1.83–4.34], p < 0.001
Musculoskeletal & Joint Diseases	65 (3.9%)	40 (1.3%)	2.49 [1.69–3.67], p < 0.001
*OR = Odds Ratio, 95% CI = Confidence Interval and corresponding p-value for the Intellectual Disabilities group effect with the General Population as the reference group. All regression models are adjusted for sex, age, and SIMD.

Table 3 shows the most commonly prescribed drugs (ranked 1–10) with anticholinergic effects for the intellectual disabilities group; 5 are psychotropics, 3 are cardiovascular, and the remaining 2 are gastrointestinal.

Table 3

Top 10 anticholinergic medicines prescribed in adults with intellectual disabilities compared to general population controls.
Medication (ARS risk category)	ID (n = 1,654)	Rank	GPop (n = 3,047)	Rank
Omeprazole (1)	26.5%	1	29.0%	1
Carbamazepine (1)	16.4%	2	1.5%	29
Lansoprazole (1)	12.9%	3	12.6%	4
Ramipril (1)	11.9%	4	15.3%	3
Lamotrigine (1)	10.6%	5	1.1%	34
Risperidone (1)	10.2%	6	0.9%	38
Amlodipine (1)	9.6%	7	17.1%	2
Sertraline (2)	9.0%	8	9.3%	6
Diazepam (2)	7.9%	9	5.7%	11
Bendroflumethiazide (1)	6.2%	10	9.9%	5
GPop = General Population, ID = Intellectual Disabilities. Percentages are presented from the subgroup sample taking long-term anticholinergics.

Psychotropic prescribing

Of the anticholinergic central nervous system drugs that were prescribed, the majority (> 99%) were psychotropics (antipsychotics, antiepileptics, antidepressants, anxiolytics/hypnotics). Compared to the adults without intellectual disabilities, regardless of sex, age or neighbourhood deprivation, adults with intellectual disabilities had greater odds of being prescribed anticholinergic drugs that were antipsychotics (5.37 [4.40–6.57]); antiepileptics (2.57 [2.22–2.99]); and anxiolytics/hypnotics (1.28 [1.06–1.56]), all statistically significant at p < 0.01. The likelihood of anticholinergic antidepressant prescribing was similar between the groups (p = 0.174). Table 4 shows the number and percentage of adults with, and without, intellectual disabilities prescribed psychotropic drugs for each of these subcategories.

Table 4

Number and percentage of adults with intellectual disabilities prescribed anticholinergic psychotropic medication by subcategory, in comparison to general population adults.
Psychotropic subcategory	Intellectual Disabilities (n = 1,654)	General Population (n = 3,047)	OR [95% CI], p-value*
Antipsychotics	411 (24.9%)	173 (5.7%)	5.37 [4.40–6.57], p < 0.001
Antiepileptics	486 (29.4%)	393 (12.9%)	2.57 [2.22–2.99], p < 0.001
Antidepressants	206 (12.5%)	383 (12.6%)	0.87 [0.71–1.06], p = 0.174
Anxiolytics/hypnotics	222 (13.4%)	289 (9.5%)	1.28 [1.06–1.56], p = 0.012
*OR = Odds Ratio, 95% CI = Confidence Interval and corresponding p-value for the Intellectual Disabilities group effect with the General Population as the reference group. Numbers and percentages are presented from the subgroup sample taking long-term anticholinergics. All regression models are adjusted for sex, age, and SIMD.

Extending these findings to include the interaction terms between group and the main effects (sex, age, neighbourhood deprivation), revealed some statistically significant results. The interaction between group and age was significant for antipsychotics (p<0.001), antidepressants (p<0.001) and anxiolytics/hypnotics (p=0.01), whilst the interaction between group and neighbourhood deprivation was significant for antiepileptics (p<0.001). ORs for the subgroup analyses by age (Additional File Table 1) and deprivation (Additional File Table 2) are reported. Figure 1 plots the MERs by group and age, averaging across sex and SIMD, demonstrating the change in risk factors that affect the probability that the individual is on a specific type of psychotropic (1 representing a 100% likelihood).

Prescribing of antipsychotics in the general population decreased from younger to older adults, but for adults with intellectual disabilities it peaked at 55–64 years old, hence the extent of the difference between the groups increased with age (Fig. 1a). Antipsychotic statistically significant group differences start from age group 25–34 (2.48 [1.34–4.60]), rising over each age group, to age 75+ (61.07 [13.11-284.44]) (Additional File Table 1). Age-related prescribing patterns of antidepressant and anxiolytic/hypnotics showed fewer statistically significant results. Whereas the general population show a decrease in antidepressant prescriptions from younger to older adults, the intellectual disabilities group fluctuated; ORs were significantly lower for the intellectual disabilities group at ages 17–24 (0.06 [0.01–0.27]), and higher for ages 65–74 (2.21 [1.35–3.64])(Fig. 1b, Additional File Table 1). Differences in anxiolytic prescribing between the groups were statistically significant, with increased prescribing for the intellectual disabilities group for 17–24 year olds (2.76 [1.00-7.63]) and 55–64 year olds (1.97 [1.28–3.03]) but did not differ at other ages (Additional File Table 1). With regards to antiepileptics, the extent of differences between groups showed a positive gradient across SIMD, with the smallest difference in the most deprived neighbourhood (1.94 [1.59–2.37]), and the greatest difference being in more affluent areas (8.77 [3.64–21.15]) (Additional File Table 2 and Fig. 1). This was due to higher prescriptions of antiepileptics in more deprived neighbourhoods in the general population, but not in the adults with intellectual disabilities.

Polypharmacy

The range of different anticholinergic drugs a person was prescribed was between 1–11 medications for both groups, with median of 2. Anticholinergic polypharmacy (concurrent use of 2 + anticholinergic medications) was significantly higher in the adults with intellectual disabilities group with 61.3% (n = 1,013) prevalence compared to 54.7% (n = 1,668) (OR = 1.61 [1.41–1.83], p < 0.001). Psychotropic polypharmacy (concurrent use of 2 + psychotropic medications) was also significantly higher in the adults with intellectual disabilities group with 33.7% (n = 558) prevalence compared to 14.3% (n = 435)(OR = 2.79 [2.41–3.23], p < 0.001). These results are adjusted for age, sex, and neighbourhood deprivation. Adults with intellectual disabilities are almost three times more likely to be exposed to psychotropic polypharmacy compared to the general population.

Principal findings and interpretation

Our findings are important, as they demonstrate that the high rates of anticholinergic burden experienced by adults with intellectual disabilities at all ages (not just older ages) are due to several classes of medications, which may be prescribed by several different clinicians. Whilst the general practitioner has an overview, it is important for all clinicians to be cognisant of this issue. Of the 38.4% of adults with intellectual disabilities on long-term anticholinergic prescriptions, the medications most frequently prescribed were central nervous system medications (62.6%), gastro-intestinal medications (46.7%), and cardiovascular medications (28.4%), and polypharmacy was more common than monotherapy.

Examining psychotropic contributions to anticholinergic burden showed that adults with intellectual disabilities were more likely to be prescribed antipsychotics, antiepileptics and anxiolytics/hypnotics compared to adults without intellectual disabilities, and had similar levels of antidepressant prescriptions. Regarding anticholinergic antiepileptics, the greatest group difference was in the most affluent neighbourhoods. This reflects the higher rates of prescribing in more deprived areas in the adults without intellectual disabilities, which is a typical finding in the general population,¹⁰ whereas for adults with intellectual disabilities antiepileptic prescribing is high across all neighbourhoods. This highlights the need for medication reviews and service provision in all neighbourhoods regardless of extent of deprivation.

Polypharmacy

Anticholinergic polypharmacy across all drug classes was present, and at 1.5 greater odds for the adults with intellectual disabilities. The combination of multiple lower risk drugs (ARS score 1) and high polypharmacy contributes to the overall clinical risk of high anticholinergic burden. A realistic medicine patient centred approach is key and the prescription of psychotropic medication should be “informed by a comprehensive biopsychosocial assessment”.¹⁵ Rates of multimorbidity (physical and mental ill-health) are high in people with intellectual disabilities,¹⁰ so polypharmacy (including psychotropic) is often indicated and appropriate. For example, around 25% of adults with intellectual disabilities have epilepsy requiring antiepileptic medications.¹⁷

Clinical services are typically organised around single conditions, which can pose additional risks for polypharmacy. Comprehensive, regular, and targeted medication reviews would help to identify excess prescribing. To see where medications can be rationalised one drug at a time, to establish support for treatment adherence, to enable good communication between the person’s different health care professionals/teams if they are accessing multiple services, and not focus simply on single-disease care pathways. This is well recognised in the general population, e.g. recent NICE clinical guideline on multimorbidity,¹⁸ but has received little attention for people with intellectual disabilities. For example, a review on the effectiveness of medication reviews for those with intellectual disabilities included only 8 studies, with just 3 of good quality; all of which evidenced the reduction in medication related problems after multidisciplinary medication reviews.¹⁹

Comparison with previous literature

Inappropriate polypharmacy is a problem among adults with intellectual disabilities and has a high risk of adverse effects. Previous evidence from representative population samples of adults with intellectual disabilities report a high prevalence of medicine use and polypharmacy (between 21%-38%), as well as psychotropic polypharmacy (between 23–41%).^20–22 Higher rates of polypharmacy (54%) and psychotropic polypharmacy (66%) have been reported in older adults with intellectual disabilities (aged 40+).^2,23 Our data are comparable to these results; similarly to Axmon et al.,¹ we find that most adults take at least 2 anticholinergic medications. Our data include only anticholinergic prescriptions, therefore are likely an underestimation of overall prescriptions e.g. many adults with intellectual disabilities take the antiepileptic sodium valproate, which is psychotropic but not anticholinergic. Similarly, although 33.7% prevalence of psychotropic polypharmacy aligns with previous evidence, it is likely an underestimation of overall prescribed psychotropic medications.

Polypharmacy and anticholinergic burden are interrelated, but both show an independent dose-response relationship with all-cause hospital admissions and mortality in older general population adults.^24,25 Polypharmacy prevalence is increasing; a recent UK Biobank study reported anticholinergic burden to be 3–9 times higher between 1990 and 2015.²⁶ Inappropriate prescriptions pose a health risk, but for those with intellectual disabilities there is evidence that every prescribed drug leads to an increase in having a potential drug-drug interaction of clinical significance (OR = 0.87 [0.72-1.00]).²¹ People with intellectual disabilities often experience multimorbidity which may necessitate polypharmacy, but this can also mean increased exposure to potential drug-drug interactions. Moreover, both polypharmacy and multimorbidity were significant predictors for mortality in older (aged 50+) adults with intellectual disabilities.²⁷ The precise relationship between multimorbidity, polypharmacy, anticholinergic burden, and mortality is yet to be clarified.

Strengths and Limitations

The strength of the current study lies in the sample; ours was a large representative group of adults with intellectual disabilities age-, sex-, and neighbourhood deprivation-matched to general population adults without intellectual disabilities within Scotland’s largest NHS health board. The use of this record linkage allows for robust information on prescribed medication with anticholinergic effects, although only a year of data was analysed. The study’s specific focus is on anticholinergic medication, and not the total rates of encashed prescriptions; so conclusions on overall prescribing cannot be drawn. Additionally, as this is prescription data there is no clarity of patient usage, dosage, or clinical indication. Therefore, an important limitation is the lack of clinical data on the conditions, diseases, or indeed, actual anticholinergic burden as measured by serum activity assays. There is also a lack of information on the severity of the intellectual disabilities.

In line with evidence from the general population, our data clearly show that drugs with a moderate anticholinergic risk from different drug classes contribute to the risk of clinically high anticholinergic burden.²⁸ People with intellectual disabilities are particularly vulnerable, with commonplace psychotropic polypharmacy as well as overall anticholinergic polypharmacy. Many people with intellectual disabilities are on antipsychotic medication over years and sometimes decades,^14,29 despite associated health risks, including anticholinergic effects. However, following NHS England’s “Stopping over-medication of people with a learning disability, autism or both (STOMP)” initiative,¹¹ there is some evidence of successful antipsychotic deprescribing,³⁰ but these prescriptions may be being replaced with other psychotropics, namely antidepressants,³¹ which could contribute to anticholinergic burden similarly. There is a need for robust evidence based recommendations for all prescribers specifically about people with intellectual disabilities with multiple physical and mental ill-health conditions to optimise medication use. Although pharmacotherapy for those with intellectual disabilities is particularly complex, prescribers may not prioritise reducing the risk of anticholinergic burden. Our results show that we should be cautious about the concurrent use of multiple low risk anticholinergic medications. It is imperative that anticholinergic prescribing, and particularly psychotropic prescribing, should be considered alongside the known health risks, and subsequently reviewed for efficacy, tolerability, and safety.

Ethics approval and consent to participate

The research was approved by Scotland’s Public Benefit and Privacy Panel for Health and Social Care (reference 1516-0281). As this was a data linkage project using electronic health records data there was no consent to participate required. Data was linked and shared with the research team within Scotland’s local Safe Haven following the necessary legal and governance approvals.

Consent for publication

Not applicable

Availability of data and materials

All data generated or analysed during the study are included in this published article (and its additional files).

Competing interests

The authors declare that they have no competing interests.

Funding

The authors would like to acknowledge the financial support of the Baily Thomas Charitable Fund (registered charity number 262334).

Authors’ contributions

LW , SA-C, AH and DK contributed to the concept and design of the work. LW led the analysis with the support of BS and NG. All authors contributed to the interpretation of data. LW led the original draft writing with the help of S-AC, CP, AH and DK. All authors revised, edited, and approved the manuscript for publication for important intellectual content. All authors gave the final approval of the version to be published.

Acknowledgements

The authors would like to acknowledge Public Health Scotland’s electronic Data Research and Innovation Service (eDRIS) team involved in the record linkage of the study.

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No competing interests reported.

Additionalfile1.docx

A Study On Prescriptions Contributing To The Risk Of High Anticholinergic Burden In Adults With Intellectual Disabilities: Retrospective Record Linkage Study

Status:

Version 1

Abstract

Figures

Background

Methods

Study Cohort

Statistical Analysis

Results

Demographics

Anticholinergic drugs across medication classes

Psychotropic prescribing

Polypharmacy

Discussion

Principal findings and interpretation

Polypharmacy

Comparison with previous literature

Strengths and Limitations

Conclusions

Declarations

References

Additional Declarations

Supplementary Files

Status:

Version 1