Case fatality rates after first acute coronary syndrome in persons treated for type 2 diabetes show an improving trend

Abstract

Aims/hypothesis: We analysed whether the prognosis of a first acute coronary syndrome (ACS) in patients treated for type 2 diabetes has improved. We also compared the trends in patients with and without diabetes.

Methods: We used national registers to identify all patients with clinically known type 2 diabetes in Finland during the years 1988 to 2002 (n = 222,940). All first-ever ACS events (n = 43,412) among these patients were identified using the Hospital Discharge Register and the Causes of Death Register. From the National Cardiovascular Disease Register we identified all first ACS attacks (n = 191,403) among non-diabetic patients in the country. Finally, we calculated annual age-standardised case fatality rates for ACS for three time periods: prehospital, days 0 to 27 and days 28 to 364 after the first ACS.

Results: The case fatality rate of first ACS declined significantly in both sexes at all time points considered. The declining trends were not different between patients with type 2 diabetes and those without. Among men aged 35 to 74 years, 58.5% (95% CI 57.6-59.4%) with type 2 diabetes and 44.1% (95% CI 43.8-44.5%) without diabetes had died from cardiovascular causes 1 year after their first ACS. Among women of the same age, the corresponding figures were 54.2% (95% CI 53.0-55.4%) and 36.5% (95% CI 35.9-37.1%). Men generally had higher case fatality rates than women. However, except for prehospital deaths, diabetic women had the same or even higher case fatality rates than non-diabetic men.

Conclusions/interpretation: The case fatality rates for first ACS show similar improving trends in patients with type 2 diabetes and in those without. However, case fatality rates have remained higher in patients with type 2 diabetes.