The effects of support, adherence, and behaviors chosen in contingency contracts on metabolic outcomes in persons with type II diabetes mellitus.

Abstract

This study examined the effects of support, adherence, and behaviors chosen in contingency contracts on the metabolic outcomes of body mass index (BMI) and glycated hemoglobin (HbA) in persons with type II diabetes. 117 subjects who participated in an earlier study utilizing contingency contracting for behavioral change were included in this secondary analysis. Specific support for diet was significantly correlated with diet adherence. Those with high initial BMI had significantly less general diabetes support and poorer diet adherence, while those with high initial HbA had significantly less diet support. Men gained weight during the study, in spite of significantly lower levels of diet support than women; while women lost weight in spite of significantly lower levels of diet support and higher initial levels of BMI. Contingency contracts were written for diet or exercise when adherence to these behaviors was low. Multiple regression analyses were used to determine predictors of variance in outcome measures of BMI and HbA for subsamples based on diet adherence and support or exercise adherence and support. For the diet subsample, 33% of the variability in percent change in HbA was predicted by study variables; only age and initial HbA were significant. Only 13% of the variability in BMI was predicted, with gender being the only significant variable. For the exercise subsample, 39% of the variability in percent change HbA was predicted; with age and initial HbA again being significant. Variance in percent change BMI predicted by study variables was only 4%; support for diet and gender were significant. While contingency contracting did not affect metabolic outcomes, this study points out that individuals tended to choose behaviors that needed to be increased, based on their self-reports of adherence. While support appears to facilitate adherence, it may be more helpful for some types of clients than others. Understanding the meaning of supportive behaviors of family and friends may assist nurses to incorporate diabetes support into treatment plans of persons with type II diabetes.