Lifestyle modification improves risk factors in type 2 diabetes relatives

To investigate the short-term (16 weeks) effect of lifestyle intervention on insulin sensitivity, anthropometric and metabolic variables in non-diabetic first-degree relatives of type 2 diabetic patients (FDR).

Seventy-seven (49 male, 28 female) FDR were allocated to one of three groups, diet (D-group; n = 25), diet and exercise (DE-group; n = 30) or control group (C-group; n = 22). Lifestyle counselling was based on current nutrition recommendations, including increased intake of fatty fish and low glycaemic index foods. Group counselling was given on two occasions with follow-up through telephone interviews every 10 days. Assessments included insulin sensitivity index (Si), anthropometry, lipid parameters, circulating leptin and adiponectin levels.

The D-group reduced total cholesterol (-0.31 mmol/l, P = 0.024), LDL cholesterol (-0.22 mmol/l, P = 0.021) and apolipoprotein B (-9.5 mg/dl, P = 0.009) levels, whereas the DE-group decreased body weight (-2.1%, P = 0.030) and waist circumference (-3.0 cm, P < 0.001) versus controls. A 13% reduction in fasting insulin was observed in the DE-group, but no significant improvement in Si in D-group or DE-group was observed. A subgroup, adherent to diet and who increased exercise, significantly improved Si and lipid profile.

The improved metabolic risk profile in FDR suggests that lifestyle changes can be effective in individuals at high risk to develop type 2 diabetes and cardiovascular disease.