Background: Relatives of type 2 diabetes mellitus (DM2) patients present or can develop the plurimetabolic syndrome (MS). Insulin sensitivity determination could be useful to detect relatives with higher risk.
Patients and methods: Insulin sensitivity (IS) and MS in 106 first degree relatives of DM2 and 52 control subjects, matched for age, sex and body mass index (BMI). Insulin sensitivity was evaluated by the HOMA method. Insulin sensitivity was classified as high, middle or low according to the percentiles 33 and 66 observed in the control group. MS was diagnosed if hyperglycemia, hypertension, hypertriglyceridemia and overweight (two or more) were present.
Results: Insulin sensitivity was lower in relatives (36.3 vs 51.8%; p = 0.0001). Relatives with lower insulin sensitivity (n = 56) have higher BMI (29.2 vs 25.6 kg/m2), higher systolic (128 vs 116 mmHg) and diastolic (80 vs 74) blood pressure, hyperglycemia (5.7 vs 5.1 mmol/l), hyperinsulinemia (116 vs 59 pmol/l) and hypertriglyceridemia (1.4 vs 1.0 mmol/l) when compared with the remainder relatives (n = 50). Age, sex, waist/hip ratio and cholesterol level were similar in both groups. 23 relatives have MS (20 of them with low insulin sensitivity, relative risk = 8.7; 95% confidence interval 2.4-31.6). In multiple logistic regression analysis, only age and IS have a significant value to predict the presence of MS.
Conclusions: Relatives of DM2 are insulin-resistant and present a high prevalence of MS. Both insulin sensitivity and MS are highly correlated. Insulin sensitivity evaluation using a simple methodology like HOMA can be useful in the selection of relatives at higher risk of MS.