Polypharmacy Among Older Adults With Dementia Compared With Those Without Dementia in the United States

Matthew E. Growdon MD, MPH; Siqi Gan MPH; Kristine Yaffe MD; Michael A. Steinman MD


J Am Geriatr Soc. 2021;69(9):2464-2475. 

In This Article

Abstract and Introduction


Background/Objectives: In older persons with dementia (PWD), extensive medication use is often unnecessary, discordant with goals of care, and possibly harmful. The objective of this study was to determine the prevalence and medication constituents of polypharmacy among older PWD attending outpatient visits in the United States.

Design: Cross-sectional analysis.

Setting and Participants: PWD and persons without dementia (PWOD) aged ≥65 years attending outpatient visits recorded in the nationally representative National Ambulatory Medical Care Survey (NAMCS), 2014–2016.

Measurements: PWD were identified as those with a diagnosis of dementia on the NAMCS encounter form and/or those receiving an anti-dementia medication. Visits with PWD and PWOD were compared in terms of sociodemographic, practice/physician factors, comorbidities, and prescribing outcomes. Regression analyses examined the effect of dementia diagnosis on contributions by clinically relevant medication categories to polypharmacy (defined as being prescribed ≥5 prescription and/or nonprescription medications).

Results: The unweighted sample involved 918 visits for PWD and 26,543 visits for PWOD, representing 29.0 and 780 million outpatient visits. PWD had a median age of 81 and on average had 2.8 comorbidities other than dementia; 63% were female. The median number of medications in PWD was eight compared with three in PWOD (p < 0.001). After adjustment, PWD had significantly higher odds of being prescribed ≥5 medications (AOR 3.0; 95% CI: 2.1–4.3) or ≥10 medications (AOR 2.8; 95% CI: 2.0–4.2) compared with PWOD. The largest sources of medications among PWD were cardiovascular and central nervous system medications; usage from other categories was generally elevated in PWD compared with PWOD. PWD had higher odds of receiving at least one highly sedating or anticholinergic medication (AOR 2.5; 95% CI: 1.6–3.9).

Conclusion: In a representative sample of outpatient visits, polypharmacy was extremely common among PWD, driven by a wide array of medication categories. Addressing polypharmacy in PWD will require cross-cutting and multidisciplinary approaches.


Polypharmacy is associated with a host of adverse outcomes among older adults, including drug reactions and use of potentially inappropriate medications (PIMs), significant morbidity such as falls and cognitive decline, and mortality.[1–4] Although many medications may be prescribed in line with chronic disease-specific guidelines, some medications have limited value, are discordant with goals of care, and are associated with more harm than benefit in older adults.[5] This challenging clinical and public health situation is encapsulated by the care of people with dementia (PWD), a growing population and widely recognized health system priority in the United States and internationally.[6,7] People living with Alzheimer's disease and related dementias often have multimorbidity[8] and are particularly vulnerable to the occurrence and risks of polypharmacy given the potential for communication barriers between providers, patients, and caregivers, cognitive and functional changes associated with the disease, and evolving goals of care in the context of reduced life expectancy.[9] Moreover, specific medications including anticholinergic and sedative medications have been linked with increased risk of hospitalization and mortality among PWD.[10] As a result, recent literature has highlighted the importance of safe prescribing[11] and the promise of deprescribing interventions[12] for this vulnerable population.

Surprisingly, nationally representative data regarding overall prescribing practices among the estimated 3.4 million PWD living in the community[13] in the United States are sparse.[1,9] Studies have documented high prevalence of polypharmacy and exposure to PIMs among PWD, but these primarily represent nursing home settings and more advanced stages of dementia or do not involve a random national sample of PWD, limiting generalizability.[9,14–18] Additionally, many studies have focused specifically on the role of central nervous system-active polypharmacy[19] or PIMs such as anticholinergic medications in prescribing practices related to PWD.[20–22] Given that the majority of adverse drug reactions affecting older adults result from medications that are not necessarily considered inappropriate in this age group,[23,24] a broad perspective on the full breadth of medication categories contributing to polypharmacy among PWD is necessary.

Using nationally representative data, we aimed to profile polypharmacy among PWD by comparing polypharmacy prevalence and medication categories contributing to polypharmacy between older adults with dementia and people without dementia (PWOD) attending outpatient visits in the United States. Additionally, we aimed to compare exposure to highly anticholinergic and sedating medications in these groups. We explored associations between the diagnosis of dementia and both polypharmacy and prescribing of clinically relevant medication categories, accounting for factors including age, sex, and comorbidity burden. Better understanding of the overall medication use of community-dwelling PWD is critical to designing clinical and health system interventions to reduce potentially unnecessary, harmful, or goal-discordant medication exposure in this population.