Control Beliefs and Risk for Death, Stroke and Myocardial Infarction in Middle-aged and Older Adults: An Observational Study.

BACKGROUND

Chronic health conditions account for the largest proportion of illness-related mortality and morbidity as well as most of healthcare spending in the USA. Control beliefs may be important for outcomes in individuals with chronic illness.

OBJECTIVE

To determine whether control beliefs are associated with the risk for death, incident stroke and incident myocardial infarction (MI), particularly for individuals with diabetes mellitus (DM) and/or hypertension.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 5,662 respondents to the Health and Retirement Study with baseline health, demographic and psychological data in 2006, with no history of previous stroke or MI.

MAIN MEASURES

Perceived global control, measured as two dimensions--"constraints" and "mastery"--and health-specific control were self-reported. Event-free survival was measured in years, where "event" was the composite of death, incident stroke and MI. Year of stroke or MI was self-reported; year of death was obtained from respondents' family.

KEY RESULTS

Mean baseline age was 66.2 years; 994 (16.7%) had DM and 3,023 (53.4%) hypertension. Overall, 173 (3.1%) suffered incident strokes, 129 (2.3%) had incident MI, and 465 (8.2%) died. There were no significant interactions between control beliefs and baseline DM or hypertension in predicting event-free survival. Elevated adjusted hazard ratios (HRs) were associated with DM (1.33, 95 % CI 1.07-1.67), hypertension (1.31, 95% CI 1.07-1.61) and perceived constraints in the third (1.55, 95% CI 1.12-2.15) and fourth quartiles (1.61, 95% CI 1.14-2.26). Health-specific control scores in the third (HR 0.78, 95% CI 0.59-1.03) and fourth quartiles (HR 0.70, 95% CI 0.53-0.92) were protective, but only the latter category had a statistically significant decreased risk. Combined high perceived constraints and low health-specific control had the highest risk (HR 1.93, 95% CI 1.41-2.64).

CONCLUSIONS

Control beliefs were not associated with differential risk for those with DM and/or hypertension, but they predicted significant differences in event-free survival for the general cohort.