For adolescents with type 1 diabetes, psychological screener scores are associated with diabetes-specific health behaviors and outcomes measured one year later. More anxiety symptoms predict higher HbA1c values, while depressive symptoms predict less frequent BGM and poorer QOL. Results from questionnaires that take less than ten minutes to complete can predict these outcomes, which are known to increase the risk for diabetes complications [
19]. Predictions can provide a valuable index of risk up to one year in advance.
Symptoms of anxiety were associated with poorer glycemic control, and symptoms of depression were linked with lower BGM frequency and QOL. Depression can detract from BGM and other diabetes management tasks via decreased motivation and energy or declines in concentration and memory, all of which can interfere with successful completion of diabetes self-care [
2,
3,
5,
15]. While the lack of an association between depression and HbA1c was surprising, symptoms of depression may have had an indirect impact on glycemic control through their strong association with BGM frequency, similar to prior studies [
5,
15,
21]. Anxiety symptoms can mimic those related to hyper- or hypoglycemia (e.g., dizziness) and may make it difficult to accurately assess and treat blood glucose levels, subsequently impacting HbA1c values. Further, biological mechanisms related to the stress response may link anxiety and HbA1c [
20]. Although depression and anxiety scores demonstrated different associations with BGM and HbA1c, it may be that they both represent a general state of psychological distress that is associated with deteriorations in diabetes management and outcomes.
Consistent with previous research [
22], depressive symptoms were associated with poorer QOL, possibly reflecting common underlying features such as mood or emotional adjustment. Independent of diabetes, experiencing the unpleasant symptoms that characterize depression likely detracts from the perception of having good QOL. In addition, poorer treatment adherence is a characteristic of lower QOL [
23]. Given that depression detracts from BGM frequency, depression may also be associated with QOL through poorer adherence.
Results of models contrasting continuous and cutoff screener scores highlight the relative benefit of using continuous scores for clinic-based screening. Elevated risk for later health and QOL problems, even among those adolescents at subclinical levels, are identified with continuous scores. Many at-risk teens would be missed by the screeners if cut-off scores were used. This may be of particular concern in light of potentially elevated mean scores in this population [
3,
4] that could increase the clinical cut-off threshold. Identifying and preventively addressing subthreshold symptom elevations is crucial to slow or reverse deterioration in diabetes outcomes before they reach clinically significant levels.
In this sample, adolescents who received insulin via MDI versus CSII were at increased risk for poorer 12-month outcomes in all areas. This is consistent with previous research indicating a clinical benefit of CSII [
24]. Parents’ marital status was also associated with multiple outcomes in this study. Single parents may have fewer resources to monitor and supervise diabetes management, which can impact both BGM frequency and glycemic control. In the context of these demographic and medical covariates, CDI and STAIC-state scores were relevant but not sole predictors of glycemic control, adherence, and QOL.
A limitation of the study is that baseline levels of BGM frequency, HbA1c, and QOL were not included in the multivariate models. The auto-correlations of these variables across time would attenuate the associations with screener scores at follow-up and limit our investigation of clinically meaningful questions about psychological screeners as predictors of health outcomes. In addition, the demographic characteristics of the study sample may limit the applicability of the findings to other, more diverse populations. Finally, readers should consider that adolescents with more depressive symptoms at baseline had more visits with mental health providers over the subsequent observation period, and depression scores did not significantly predict BGM when visit frequency was included in the model. This suggests that psychological treatment may decrease depressive symptoms and thus buffer the impact on adherence.
The results of this study highlight the utility of psychological screeners to predict BGM frequency, HbA1c, and QOL measured one year later in adolescents with type 1 diabetes. Clinic-based screening for depression and anxiety symptoms will help to identify psychological concerns linked with diabetes management. Importantly, these concerns are associated with risk for rising HbA1c values, a critical diabetes outcome. Research on the implementation of such screening processes through quality improvement (QI) methodology is needed to address challenges such as time requirements, costs, and responding to elevated scores. The timeframe for this study was one year and suggested annual screening, although additional research is needed to determine the optimal frequency of screening.
Medical providers including physicians, nurse practitioners, and social workers are a primary avenue by which at-risk patients can be routed to mental health providers to address behavioral and psychological factors contributing to poor health outcomes. Evidence-based cognitive-behavioral treatments for adolescents with mood and anxiety disturbances [
25] have the potential to be successfully integrated with illness-specific interventions designed to enhance adherence, glycemic control, and QOL [
24,
25] among adolescents at elevated risk due to mental health symptoms. A relatively large reduction in depressive and anxiety symptoms would be needed to result in the expected improvements in HbA1c, BGM frequency, and QOL, likely requiring substantial psychological intervention. Psychological screening and referral to appropriate intervention hold promise for early identification and may ultimately help prevent deteriorations in diabetes management and glycemic control.