Can type 2 diabetes be prevented in UK general practice? A lifestyle-change feasibility study (ISAIAH).

The increasing incidence of type 2 diabetes mellitus is attributed to increasing weight, reduced physical activity, and poor diet quality. Lifestyle change in patients with pre-diabetes can reduce progression to diabetes but this is difficult to achieve in practice. To study the effectiveness of a lifestyle-change intervention for pre-diabetes in general practice. A feasibility study. A medium-sized general practice in Sheffield. Participants were 33 patients with pre-diabetes. The intervention was a 6-month delayed entry comparison of usual treatment with a lifestyle-change programme: increased exercise and diet change, either reduction in glycaemic load, or reduced-fat diet. The main outcome measures were weight, body mass index (BMI), waist circumference, fasting glucose, lipid profile, and nutrition. A statistically significant difference was observed between control and intervention groups in three markers for risk of progression to diabetes (weight (P<0.03), BMI (P<0.03), and waist circumference (P<0.001)). No significant differences in fasting glucose or lipid profiles were seen. Aggregated data showed a statistically non-significant improvement in all the measures of metabolic risk of progression to diabetes in the low-glycaemic-load group when compared with a low-fat-diet group (P>0.05). Significant total energy, fat, and carbohydrate intake reduction was achieved and maintained in both groups. A lifestyle-change intervention feasibility programme for pre-diabetic patients was implemented in general clinical practice. The potential of a low-glycaemic-load diet to be more effective than a low-fat diet in promoting change in the features associated with progression to diabetes is worthy of further investigation.