Diabetes risk reduction in primary care: Evaluation of the Ontario Primary Care Diabetes Prevention Program

Lifestyle interventions can reduce type 2 diabetes risk. The Primary Care Diabetes Prevention Program (PCDPP) was implemented by the Government of Ontario to lower diabetes risk. This study first evaluated the program, and second used a validated tool to estimate a potential population impact if the program were implemented more broadly in the province.

PCDPP was implemented in six primary care settings serving communities with high mortality risk due to chronic diseases. In total, 1916 adults with prediabetes or metabolic syndrome were enrolled from January 2011 to December 2012. Body weight was the primary outcome variable, and was modeled using four time periods (i.e., baseline, 3rd, 6th and 9th month). The intervention effect was estimated using multilevel mixed-effects linear regression, and was stratified by gender and age. In the population impact analysis, a number needed to treat (NNT) for the intervention to prevent one case of diabetes and an absolute number of diabetes cases averted were estimated.

Weight loss over 9 months was 7.5% (or 6.8 kg), with 7.4% (or 6.4 kg) in females and 8.6% (or 8.6 kg) in males. When modeled, changes in weight were all statistically significant. The models for male participants predicted, however, some gains in weight in the last 3 months of the program. Dropout rates were 26.8%, 46.8% and 63.0% at 3rd, 6th and 9th month respectively. Scaling up the program would produce an NNT of approximately 36 and would avert 6401 cases of diabetes in five years.

PCDPP may represent a potentially effective tool for population-level diabetes risk reduction.