Psychosocial factors have been reported to be independently associated with coronary
heart disease. However, previous studies have been in mainly North American or European
populations. The aim of the present analysis was to investigate the relation of psychosocial
factors to risk of myocardial infarction in 24767 people from 52 countries.
We used a case-control design with 11119 patients with a first myocardial infarction
and 13648 age-matched (up to 5 years older or younger) and sex-matched controls from
262 centres in Asia, Europe, the Middle East, Africa, Australia, and North and South
America. Data for demographic factors, education, income, and cardiovascular risk
factors were obtained by standardised approaches. Psychosocial stress was assessed
by four simple questions about stress at work and at home, financial stress, and major
life events in the past year. Additional questions assessed locus of control and presence
of depression.
People with myocardial infarction (cases) reported higher prevalence of all four stress
factors (p<0.0001). Of those cases still working, 23.0% (n=1249) experienced several
periods of work stress compared with 17.9% (1324) of controls, and 10.0% (540) experienced
permanent work stress during the previous year versus 5.0% (372) of controls. Odds
ratios were 1.38 (99% CI 1.19-1.61) for several periods of work stress and 2.14 (1.73-2.64)
for permanent stress at work, adjusted for age, sex, geographic region, and smoking.
11.6% (1288) of cases had several periods of stress at home compared with 8.6% (1179)
of controls (odds ratio 1.52 [99% CI 1.34-1.72]), and 3.5% (384) of cases reported
permanent stress at home versus 1.9% (253) of controls (2.12 [1.68-2.65]). General
stress (work, home, or both) was associated with an odds ratio of 1.45 (99% CI 1.30-1.61)
for several periods and 2.17 (1.84-2.55) for permanent stress. Severe financial stress
was more typical in cases than controls (14.6% [1622] vs 12.2% [1659]; odds ratio
1.33 [99% CI 1.19-1.48]). Stressful life events in the past year were also more frequent
in cases than controls (16.1% [1790] vs 13.0% [1771]; 1.48 [1.33-1.64]), as was depression
(24.0% [2673] vs 17.6% [2404]; odds ratio 1.55 [1.42-1.69]). These differences were
consistent across regions, in different ethnic groups, and in men and women.
Presence of psychosocial stressors is associated with increased risk of acute myocardial
infarction, suggesting that approaches aimed at modifying these factors should be
developed.