Objectives: There are considerable differences in individual health education programs for persons at high risk of type 2 diabetes between ordinary Japanese life-style modification programs and the Diabetes Prevention Program in the US, the former being relatively moderate and the latter more intensive. We therefore compared the effectiveness of intensive and moderate intervention, focusing on the frequency of individual educational classes.
Methods: The subjects were men and women aged 44-69 years living in Nishiaizu town, Fukushima prefecture in Japan. Their fasting plasma glucose concentration was between 95 and 125 mg/dl at health examinations conducted in 2002 or 2003. They also had a body mass index (BMI) of 23.0 or higher, a fasting plasma glucose concentration of 125 mg/dl or lower and a post-load plasma glucose concentration (2 h) of 199 mg/dl or lower in the 2004 survey. We assigned the subjects according to their residences to an intensive life-style intervention group (two education classes per month; n = 11) or a moderate intervention group (one education class per month; n = 14). The main outcome measure was the change in body weight after 6 months of intervention.
Results: The loss of body weight was -3.5 kg (P< .0001) in the intensive intervention group and -1.8 kg (P = 0.02) in the moderate group, and the net difference in body weight loss between the groups was -2.0 kg (95% confidence interval -4.0 to -0.05; P = 0.045) after adjustment for age, sex, and baseline body weight. BMI and subcutaneous fat area showed similar results. The post-load plasma glucose concentration (2 h) and other tested values showed no significant net change between the two groups.
Conclusions: Intensive and moderate intervention both reduced body weight in overweight or obese persons at high risk of type 2 diabetes. The intensive intervention, two sessions of individual education classes per month, was significantly more effective than the moderate one for reducing body weight.