Polypharmacy and Nutritional Status in Older Adults

Background: Older adults have more chronic medical conditions, and the level of polypharmacy increases with advancing age. Malnutrition and drug nutrient interactions are of concern in this population.

Objectives: The aims of this cross-sectional study were to examine nutritional status, the use of medications, and drug-nutrient interactions in older adults.

Methods: Interviewer-administered surveys were conducted in 1100 community-dwelling older (age >65 years) adults. Information regarding demographics, nutritional status, medical history and medication usage was obtained. Self-reported data were verified by third parties when feasible. Informed consent and Human Subjects Committee approval were obtained. A pilot conducted prior to the onset of the study revealed high rates of inter-rater reliability. Data were recorded and entered into Excel spreadsheets for coding and cleaning and transferred to SPSS v. 17.0 for analyses.

Results: The respondents’ mean age was 75.5 years. The top six most frequently used classes of medications were gastrointestinal agents, antihypertensives, diuretics, analgesics, β-adrenoceptor antagonists and antihyperlipidaemics. The prevalence of polypharmacy among the participants was 43.4%, with 51.1% of those participants using five or more medications. Most notable was the statistically significant inverse correlation between increasing number of medications and intake of fibre. Intake of cholesterol, glucose and sodium were positively associated with increasing medication use. A trend was also observed for increased phosphorus intake and increased number of medications used. Intake of fat-soluble vitamins, B vitamins, carotenoids and minerals was lower in those with increasing number of medications. Decrements in physical health were associated with decreasing intake of many fat-soluble and water-soluble vitamins, major minerals, trace minerals and electrolytes. Excessive macronutriture, specifically relating to the intake of saturated fats, refined carbohydrates and cholesterol, along with decreased intake of fibre and bioavailable protein sources, was also associated with poor physical health.

Conclusions: The number of medications used by older adults in this convenience sample was associated with poorer nutritional status. Decrements in physical health have a statistically significant effect on nutrient intake. Further research into these issues is required.