Diabetes NewsOctober 2009
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Prevention of Diabetes: Outcomes of the Self Management Program PREDIAS
Diabetes Care • July, 2009
The prevalence of type 2 diabetes is increasing worldwide. Diabetes is associated with an increased risk for morbidity and mortality. Meta-analysis has shown that type 2 diabetes can be effectively prevented or delayed by lifestyle modification. A group program known as PREDIAS was developed for the prevention of type 2 diabetes that is based upon the Diabetes Prevention Program. The aim of this randomized control trial was to evaluate in a 12-month follow-up the efficacy of PREDIAS with regard to the primary outcome variable, weight reduction, as well as behavioral, metabolic and psychological outcomes as secondary variable.
Objective - To evaluate the efficacy of the group program PREDIAS for diabetes prevention.
Research Design and Methods - PREDIAS was compared with a control group whose members received the PREDIAS group written information and patient information. Inclusion criteria were those aged 20-70 years with body mass index (BMI) > 26 kg/m2, impaired glucose tolerance or impaired glucose fasting. Exclusion criteria were manifest diabetes or diagnosis of a serious illness (e.g. cancer). Individuals with an elevated diabetes risk based upon a high score (>10) on the Diabetes Risk Score or according to the assessment of a primary care physician were invited to a baseline examination. After a pool of 12-20 patients was created a centrally performed block randomization (1:1) assigned subjects randomly to the PREDIAS or the control group.
The results refer to changes between baseline and the 12-month follow-up measurement. Patients underwent an oral glucose tolerance test. Weight, height, waist circumference, and blood pressure were assessed by study nurses who were blinded to the treatment assignment of the subjects. Also, lipids and A1C were measured. Glucose was measured from capillary blood samples.
The prevention program consisted of 12 lessons lasting approximately ninety minutes each. During the first eight weeks, eight core lessons were given with one per week: the last four lessons were bimonthly booster lessons. The PREDIAS program, which is based upon self-management theory, was conducted in small groups. PREDIAS was delivered either by diabetes educators or psychologists. The program comprised a set of transparencies for the lessons and a curriculum for the prevention manager. Each participant received an exercise book, which contained information about diabetes prevention. This book also contained resources for the participants such as a table of caloric values and work sheets (e.g. eating diaries and exercise log books) for each lesson.
Results - A total of 182 participants were randomized for the study. There were no significant differences between those in the PREDIAS group and the control group. The study lost 17 participants to follow-up.
After 12 months there was a significant effect on body weight. Participants in the PREDIAS group had lost 3.8 kg of weight, whereas members of the control group reduced their weight by 1.4 kg. Similar results were found regarding BMI and waist circumference.
Both groups increased their physical activity, but the increase was significantly greater in the PREDIAS than the control group. Cognitive restraint of eating behavior was significantly more increased in the PREDIAS than in the control group, and eating disinhibition was significantly more decreased in the PREDIAS than in the control group. Members of the PREDIAS showed a significant within-group reduction on the hunger scale, but there was no significant between-group difference.
There was a significant effect of PREDIAS on fasting glucose: however, the 2 hour postprandial glucose values and the A1C did not change significantly between the groups. Total cholesterol and triglycerides, as well as systolic and diastolic blood pressure, were significantly reduced in the PREDIAS group, whereas the control group there was no substantial change in the risk factors. However, the between-group difference failed to reach significance. In both groups, psychological well-being increased, whereas anxiety and depressive symptoms decreased. However, except for anxiety, there were no significant differences between the groups.
Conclusions - The PREDIAS prevention program was able to reduce weight and modify eating behavior and physical activity significantly; thus, patients with diabetes risk were reduced. The magnitude of these effects and observed metabolic changes were in the range of previously published results of diabetes prevention programs.
Reprinted with permission from the American Diabetes Association