Cardiovascular Risk Factors and the Risk of Disability in Older Adults: Variation by Age and Functional Status.

OBJECTIVES

We aimed to quantify the increased risk of disability associated with cardiovascular risk factors among older adults, and to verify whether this risk may vary by age and functional status.

DESIGN

Longitudinal population-based cohort study.

SETTING

Urban area of Stockholm, Sweden.

PARTICIPANTS

Community-dwelling and institutionalized adults ≥60 years in the Swedish National study on Aging and Care in Kungsholmen free of cardiovascular diseases and disability (n = 1756) at baseline (2001-2004).

MEASURES

Incident disability in activities of daily living (ADL) was ascertained over 9 years. Cardiovascular risk factors (physical inactivity, alcohol consumption, smoking, high blood pressure, diabetes, high body mass index, high levels of total cholesterol, and high C-reactive protein) and walking speed were assessed at baseline. Data were analyzed using Cox proportional hazards models, stratifying by younger-old (age 60-72 years) and older-old (≥78 years).

RESULTS

During the follow-up, 23 and 148 persons developed ADL-disability among the younger- and older-old, respectively. In the younger-old, the adjusted hazard ratio (HR) of developing ADL-disability was 4.10 (95% confidence interval [CI] 1.22-13.76) for physical inactivity and 5.61 (95% CI 1.17-26.82) for diabetes. In the older-old, physical inactivity was associated with incident ADL-disability (HR 1.99, 95% CI 1.36-2.93), and there was a significant interaction between physical inactivity and walking speed limitation (<0.8 m/s), showing a 6-fold higher risk of ADL-disability in those who were both physically inactive and had walking speed limitation than being active with no limitation, accounting for a population-attributable risk of 42.7%.

CONCLUSIONS/IMPLICATIONS: Interventions targeting cardiovascular risk factors may be more important for the younger-old in decreasing the risk of disability, whereas improving physical function and maintaining physical activity may be more beneficial for the older-old.