Clustering of cardiovascular risk factors in type 2 diabetes mellitus: prognostic significance and tracking.

AIM

Little attention has been paid to the prognostic significance and tracking effect of risk factor clusters characteristic of type 2 diabetes mellitus. We studied the clustering of eight cardiovascular risk factors (smoking, high body mass index, elevated systolic blood pressure, high serum, low density lipoprotein (LDL) cholesterol, high serum LDL triglycerides, low serum, high density lipoprotein (HDL) cholesterol, high fasting blood glucose and high plasma insulin concentration) and their effect on the prognosis and the tracking effect.

METHODS

This study is a population-based prospective follow-up of newly diagnosed type 2 diabetic subjects (n = 133, aged 45-64 years) in Eastern Finland. The following end points were used: all-cause mortality, cardiovascular mortality, and incidences of first myocardial infarction and first stroke. Furthermore, we studied the 'tracking effect' of the risk factor clusters during the 10-year follow-up period.

RESULTS

When the clustering of risk factors typical of type 2 diabetes mellitus was taken into account, all-cause mortality increased from 28.6% to 50.0% (p < 0.05) and cardiovascular disease mortality increased from 14.3% to 50.0% (p < 0.01) depending on the number of risk factors present. The incidence of first myocardial infarction increased from 0% to 40.0% (p < 0.05) as the number of risk factors increased from 0 to 5. In survivors, the proportion of individuals with no risk factors decreased and the proportion on individuals with three to four risk factors increased during the 10-year follow-up period despite the high mortality among the group with many risk factors.

CONCLUSIONS

The risk factor clusters among type 2 diabetic subjects are of great predictive value and when not aggressively treated, show a relentless increase despite selective mortality.