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

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.