Adherence as a Mediating Variable Between Depression and Health Outcomes in Adolescents with Type 1 Diabetes

Adolescence is often a time of diabetes mismanagement and poor metabolic control in adolescents with type 1 diabetes. Symptoms of depression are related to poor metabolic control, but the mechanism that links them is under debate. Because depression tends to be associated with poorer adherence and poor adherence has been shown to be related to poor metabolic control, it is possible that adherence serves as a mediator between the two. The present study tested this mediation pathway in a sample of adolescents with type 1 diabetes. Participants (N=252) were recruited from endocrinology clinics in Utah during their routine diabetes clinic visits. Participants fell between the ages of 10 and 14, were able to read and write in either English or Spanish, had a diagnosis of type 1 diabetes for at least one year, and did not have a condition that would interfere with measurement completion. Participants were drawn from a larger longitudinal observational study. This study analyzed the first three time points of data, which were obtained six months apart. Demographic and illness information was obtained from self-report and participant medical files. Questionnaires were used to assess depression and adherence. Metabolic control was measured through HbA1c levels retrieved from medical records. Data were analyzed to test the mediation hypotheses. Higher levels of depression were correlated with poorer metabolic control in cross-sectional analyses at study entry, and in longitudinal analyses measured one year later. Adherence was found to be a partial mediator in cross-sectional analyses, but did not mediate changes in metabolic control across time.