The Association Between Various Psychosocial Measures and Trajectory of Secondary Prevention Adherence After Myocardial Infarction

Background: A variety of psychosocial factors were previously shown to predict outcomes after myocardial infarction (MI). Additionally, adherence to medical instructions and medications is highly important in reducing recurrent cardiovascular events and mortality among MI patients. Whether psychosocial factors affect long-term adherence to secondary prevention recommendations after MI remains uncertain. Furthermore, the extent to which adherence to secondary prevention measures determines subsequent survival requires further quantification.

Methods: A cohort of patients aged ≤65 years, admitted for first-ever MI in 1992-1993, was followed up longitudinally. Dispositional optimism, perceived social support, sense of coherence, anxiety and depression were assessed at initial hospitalization in a subgroup of patients (n=616) using standard questionnaires. The extent of adherence to secondary prevention measures was recorded at four follow-up interviews: 3-6 months, 1-2 years, 5 years and 10-13 years after MI. A prevention score (calculated as proportion of recommendations met) was developed based on the following measures: (1) adherence to prescribed medications; (2) exercising regularly; (3) not smoking; (4) following a healthy diet; and (5) maintaining a recommended body weight. The association between psychosocial factors and the prevention score was estimated through Generalized Estimating Equation (GEE) models. The prognostic role of the prevention score in long-term survival was assessed using time-dependent Cox regression analysis.

Results: The average prevention score ranged from 0.7-0.8 across follow-up interviews. Both perceived social support and sense of coherence were predictive of secondary prevention adherence trajectory, even after adjustment for multiple potential confounders (Table). The prevention score in turn was a strong predictor of mortality over the 23-year follow-up (adjusted hazard ratio, 0.49; 95% CI: 0.27-0.88, per 1 SD increase in score).

Conclusions: Psychosocial factors measured after MI, particularly perceived social support and sense of coherence, were associated with a secondary prevention score. The score, derived from successive follow-up interviews, was strongly associated with survival.