Five-year incidence of type 2 diabetes mellitus in patients with familial combined hyperlipidaemia.

Background: The current study was conducted to investigate whether patients with familial combined hyperlipidaemia (FCHL ) are predisposed to the development of type 2 diabetes mellitus (T2DM).
Methods: A cohort of 56 FCHL patients and 54 spouses was followed over time with a five-year interval. Diagnosis of T2DM was based on fasting glucose levels or use of antidiabetic medication. Baseline body mass index, waist circumference, blood pressure, use of antihypertensive and lipid-lowering medication, plasma cholesterol, triglycerides, apolipoprotein B, glucose, insulin and alanine aminontransferase (ALAT) levels were determined as potential predictors of new onset T2DM.
Results: Baseline prevalence of T2DM was 2% in spouses and 9% in FCHL patients, and 4 and 20%, respectively, after five-year follow-up. The incidence of T2DM was significantly higher in FCHL patients (2 vs 14%; OR 9.1; 95% CI 1.0 to 81.4; p=0.04; age and sex adjusted). Of all baseline variables, only plasma insulin levels (not glucose) significantly predicted the development of T2DM (p=0.04).
Conclusion: The present study is the first to present incidence numbers of T2DM in FCHL and demonstrates that FCHL patients, as compared with healthy controls, are predisposed to the development of T2DM. This is - at least in part - accounted for by an increased insulin resistance.