Are there socioeconomic differences in myocardial infarction event rates and fatality among patients with angina pectoris?

Background: Systematic socioeconomic differences in mortality have been reported among myocardial infarction (MI) patients in many countries, including Finland. The findings have been similar irrespective of country, study period, age group, or length of follow up, but few studies have examined the disparities among other groups of coronary patients. This study examined whether similar socioeconomic differences in outcomes exist among patients with angina pectoris (AP). Methods: The data were based on individual register linkages among a population based 40-79 year-old cohort of 61350 patients with incident AP or MI during 1995-1998 in Finland. Two year coronary heart disease mortality and one year MI incidence and its 28 day case fatality was studied among AP patients using Cox's and logistic regression analysis, and the results compared with those of the MI patient group. Results: A clear socioeconomic pattern was found in two year coronary heart disease (CHD) mortality: the lower the socioeconomic group the higher the mortality risk. The socioeconomic patterning of mortality was similar to that found among MI patients. Controlling for comorbidity or disease severity did not change the results. Among AP patients a similar pattern was also found in MI incidence during the follow up, but no systematic socioeconomic differences were detected in its 28 day case fatality. Conclusions: Socioeconomic differences in CHD outcomes also exist among angina patients. These results suggest that targeted measures of secondary prevention are needed among CHD patients with lower socioeconomic status to reduce socioeconomic disparities in fatal and non-fatal coronary events.