A systematic review of medication non-adherence in persons with dementia or cognitive impairment

Abstract

BackgroundAdherence to medication is vital for disease management while simultaneously reducing healthcare expenditure. Older persons with cognitive impairment (CI) are at risk for non-adherence as cognitive processes are needed to manage medications. This systematic review focuses on the relationship between medication non-adherence and specific cognitive domains in persons with CI, and explores determinants of medication non-adherence. When available, relationships and factors are compared with cognitively intact populations.MethodsA seven database systematic search of studies published between 1 January 1949–31 December 2015 examining medication non-adherence in community dwelling persons with CI or dementia was conducted. Articles reporting medication non-adherence in people with CI or dementia in the community, with or without caregiver supports were eligible for inclusion. Papers reporting adherence to treatments in cognitively intact populations, populations from hospital or institutional settings, for non-prescribed medication or those describing dementia as a factor predicting medication non-adherence were excluded. Data on study and population characteristics, research design, data sources and analysis, specific cognitive domains, non-adherence prevalence, measurement of adherence, salient findings, factors associated with adherence and strategies to improve medication adherence were extracted. Study limitations included inconsistencies between data sources and definitions, resulting in a loss of fidelity in the value and comprehensiveness of data, as well as exclusion of non-pharmacological treatments and regimens.FindingsFifteen studies met inclusion criteria. Adherence among CI subjects ranged from 10.7%-38% with better rates of adherence in non-CI individuals. Medication non-adherence definitions varied considerably. New-learning, memory and executive functioning were associated with improved adherence and formed the focus of most studies. Multiple factors were identified as modulators of non-adherence.ConclusionThis review highlights a gap in knowledge on how specific cognitive domains contribute to medication non-adherence amongst CI populations, and demonstrates the current focus is limited to two domains: memory and executive functioning.

Barriers to medication adherence and links to cardiovascular disease risk factor control: the Framingham Heart Study

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“…Older adults constitute a high‐risk population for poor medication adherence; as the population ages, chronic coexisting conditions coupled with decreased cognitive functioning might lead to decreased adherence . A recent systematic review of 15 studies concluded that individuals with cognitive impairment had lower rates of medication adherence compared to those without cognitive impairment .…”

Associations of dyslipidaemia and lipid-lowering treatment with risk of postoperative cognitive dysfunction: a systematic review and meta-analysis

“…People with a lower cognitive reserve may have lower healthcare uptake67 and also appear to be at reduced risk of POCD 68. Relatedly, people with beginning cognitive impairment in older age may have difficulty with treatment adherence 69 and are also at increased POCD risk 1. Confounding by other factors such as health status at the time of undergoing surgery, too, is possible.…”

Adherence support strategies for exercise interventions in people with mild cognitive impairment and dementia: A systematic review

“…; 2 of the 6 communities also offered a structured walking programme 2–3 times a wkIndividual and situational factors influencing physical activityGroup setting, reminders from staff and through centrally located bulletin board, planning of exercise to fit into daily routine, tailoring and supervision discussedAdherence: n/aEvaluation: focus groups: group setting desirable as it also provided the opportunity to socialize; planning exercise and using reminders seen as important; individualized home exercise and supervision with a motivational leader desirable; most preferred type of exercise was walkingFairhall et al (2012), AustraliaRCTCommunity setting; intervention group: n  = 120; mean age = 83.4 (SD = 5.8); 67% women; mean MMSE = 26.6 (SD = 2.6)12 months multifactorial interdisciplinary and individually tailored intervention targeting frailty. This included 10 home based 45–60 min physiotherapy sessionsMobility related disability in terms of satisfaction and performanceGoal setting and ongoing review of goals by PT for mobility goals; assessment of barriers to goal attainment; PT identified barriers and organized additional services to help overcome barriers; components to achieve goals were practiced at home, then in target environment with decreasing degree of assistanceAdherence: median global level of adherence as estimated by the physiotherapists: 25%–50% of intervention program;Evaluation: percentage of participants completing goal focused aspect of intervention: 50%; physiotherapist organized additional services depending on barriers such as provision, modification or advice about equipment (for 40% of participants), referral to services for care of older people (for 41% of participants) or to medical care (for 30% of participants)Lindelof et al (2012), SwedenQualitative, InterviewsResidential care setting; total n  = 9; mean age = 89 (73–91); 66% women; MMSE 23 (Phillips and Flesner, 2013, Cox et al, 2013, Resnick et al, 2009, Rosenberg et al, 2012, Wu et al, 2015, Frederiksen et al, 2014, Olsen et al, 2015, Vidoni et al, 2016, Fairhall et al, 2012, Kerse et al, 2008, Lindelof et al, 2012, Smith et al, 2017); 3 diagnosed with dementia3 months of high intensity group based exercise intervention with 5 sessions lasting 45 min each held in every 2 week period prior to the interviewsViews on participating in the exercise, motivation; experience of positive and negative effects of the exerciseSupport from exercise supervisor (close supervision for exercises by 2 PTs); group setting;Adherence: n/aEvaluation: interviews: supervisors were perceived as confidence inspiring and encouraging and therefore seen as exercise facilitators; group exercise provided opportunity to socialize, which subsequently increased self-confidence – created a “sense of togetherness”Rosenberg et al (2012), USAFeasibility study using a single cohort designRetirement facility setting, total n  = 87; mean age = 84.1 (range 69–98); 76% women; included pe...…”