A conceptual framework to study medication adherence in older adults.

BACKGROUND: Adults aged > or =50 years often have multiple chronic diseases requiring multiple medications. However, even drugs with well-documented benefits are often not taken as prescribed, for a variety of reasons.

OBJECTIVE: The objective of this article was to provide background information about medication adherence and its measurement, the development of the conceptual model for use in adherence research, and supportive intervention strategies such as pharmaceutical care by pharmacists to improve chronic medication use in older adults.

METHODS: English-language literature published from 1990 to 2000 was searched on MEDLINE, International Pharmaceutical Abstracts, and AARP Ageline using the terms aged, heart failure, CHF, adherence, chronic heart failure, compliance, and related terms. The authors used their personal files and libraries to obtain seminal literature and textbooks published before 1990.

RESULTS: Although the cognitive processes needed to manage and take medications decline with aging, the number of prescription and nonprescription medications consumed increases. Other factors such as vision, hearing, health literacy, disability, and social and financial resources may all complicate the ability of older adults to adhere to the pharmacologic prescription.

CONCLUSIONS: Many factors are associated with medication adherence and related health outcomes in older adults. Therefore, strategies to improve adherence will need to be multidimensional, including improvements in pharmacy services that consider age-related factors (eg, declining cognitive and physical functions) as well as a variety of environmental and social factors.