Gender-based differences in management and outcomesof acute myocardial infarction patients: The role of health information

Background: Gender-based differences observed in access to care and outcomes have raised the concern of sexual discrimination against women. We wonder whether better health knowledge would help to narrow such “disparities,” while many argue that gender differences in medical care mainly result from clinical manifestation. Furthermore, whereas the existing evidences are limited mostly to western populations, due to heterogeneity in culture and traditional gender role patterns, gender issues in medical care may be more serious in Asian populations. We aimed to compare cardiac procedure use and mortality between men and women in Taiwan, and to determine whether such sex differences exist among health professionals.

Methodology: Retrospective analyses were conducted using the National Health Insurance data for patients, who had been admitted to a hospital for acute myocardial infarction in Taiwan during 1997-2006. A total of 70,318 eligible AMI patients aged 30 to 85 years were identified. Of these patients, only those with a monthly income greater than 40,000 NTD were analyzed. The final sample included 599 health professionals and relatives of health professionals, and 9,040 general adults. Main outcome variables included use of catheterization and revascularization within 1 year of the index admission, 30-day and 1-year mortality. Characteristics of patients, physicians and hospitals were adjusted in the models. Generalized Estimating Equations and Cox proportional hazard models were applied. Sensitivity analyses were also conducted for different age strata and socioeconomic status.

Results: General Taiwanese women not only underwent fewer cardiac catheterization (43.7% vs. 63.8%) and revascularization (34.3% vs. 56.3%) than men, but also had higher 1-year mortality rate (38.2% vs. 18.5%). In contrast, sex differences in procedure uses observed among health professionals were much smaller in magnitude (catheterization: 45.0% vs. 60.1%; P=0.005; revascularization: 39.0% vs. 53.5%; P=0.008). Nonetheless, after adjusting for potential confounders, either general women or female professionals were considerably less likely to undergo cardiac catheterization and revascularization than their male counterparts. General women and female professionals had substantially higher mortality risks than their male counterparts. Such differences were more evident among those patients aged below 65 years. Sex differences observed in procedure use and mortality (P for interactions > 0.05) were not smaller when a patient was a health professional.

Conclusions: The preliminary results suggest that health knowledge alone may not explain observed gender differences in access to invasive cardiac procedures and outcomes. Greater gender differences observed among men and women aged below 65 years deserve more attentions.