No significant gender difference in hospitalizations for acute coronary syndrome in Switzerland over the time period of 2001 to 2010.

Background: Morbidity and mortality from cardiovascular diseases have decreased since the 1970s in most Western societies. However, it is unclear if this positive trend can also be found in younger women suffering from acute coronary syndrome (ACS).

Methods: This is a prospective single center registry study including 11.015 women and men hospitalized for a first ACS between the years 2001 and 2010. We analyzed ACS rates according to sex and age group using Poisson regression in order to assess temporal trends.

Results: Overall ACS hospitalization rates per 100.000 inhabitants increased by 31% between 2001 and 2010 (Rate Ratio (RR) of 1.31, 95% CI 1.20-1.43; p<0.001) with a similar increase in men (RR 1.29, p<0.00001) and women (RR 1.35, p<0.0001). Analyses of age-specific ACS rates showed a significant increase in ACS hospitalization rates only for the age groups 70-79years (p=0.003) and 80+ years (p<0.00001). None of the age matched subgroups showed a sex related significant difference in trend for ACS hospitalization rates. Temporal trends for recorded risk factors showed a significant increase in smoking (p=0.03), and a trend to increased obesity prevalence (p=0.06) in females in the age group 60-69years.

Conclusions: In contrast to other studies, we found no evidence for a particular increase in the number of younger women referred for a first ACS during the years 2001 and 2010. Potential negative effects of smoking and obesity on ACS incidence may be delayed to women older than 70years.