Lifestyle intervention in people with insulin-dependent diabetes mellitus (IDDM).

Objective: To investigate the impact of intensive lifestyle education on dietary practices, exercise and metabolic measurements in people with insulin-dependent diabetes mellitus (IDDM).

Design: Sixty-one volunteer subjects with IDDM were randomised to intensive (Group 1) or standard (Group 2) education programmes for six months. During a second six month period of observation Group 1 subjects received routine surveillance for their condition and those in Group 2 were given intensive advice (phase 2). Current insulin regimens were modified to optimise glycaemic control before the start of the intervention phase. Nutrient intakes, weight, blood pressure, glycated haemoglobin (HbA1), plasma lipids, lipoproteins and maximal oxygen consumption (VO2 max) were measured at the time of recruitment and at three monthly intervals during the trial and phase 2.

Setting: Department of Human Nutrition at the University of Otago.

Results: Glycated haemoglobin decreased significantly in both groups between recruitment and randomisation, the improvement being sustained during the six months of the randomised trial and for group 1 during the six months of post trial observation. A further decrease was seen in Group 2 during the second six month period when they were given intensive advice. Comparable changes were seen with total and low density lipoprotein (LDL) cholesterol in Group 1 during the trial, but significant decreases were only seen in Group 2 in association with intensive intervention (phase 2). These changes occurred in parallel with increases in intakes of carbohydrate and monounsaturated fatty acids, a reduction in intakes of total and saturated fat, and an improvement in maximum oxygen consumption.

Conclusions: A lifestyle programme for people with IDDM results in modest changes in diet and exercise habits sufficient to improve measures of glycaemic control and lipoprotein mediated risk of coronary heart disease independent of changes in insulin regime. More innovative approaches to achieve lifestyle changes are required to meet current recommendations which in turn are likely to produce even greater beneficial changes than those observed here.