BACKGROUND/RATIONALE:
Depression in individuals with diabetes is common and complicates their diabetes care, and is related to negative outcomes and increased health care expenditures. There is some evidence that both pharmacologic, specifically the new generation antidepressants, and nonpharmacologic treatment for major depression improves glycemic control and good glycemic control among individuals with diabetes is related to lower health care utilization and costs. However, it has not been established in naturalistic settings, among individuals with diabetes, whether depression treatment actually improves process and intermediate outcomes of care, and decreases utilization and costs over time.
OBJECTIVE(S):
Our major hypothesis is that guideline-consistent treatment for depression will improve diabetes related treatments (i.e. adherence to antiglycemic and antilipemic medications). Guideline-consistent treatment of depression in VHA patients with DM/D will be associated with decreased likelihood of an inpatient stay over time. The association between guideline-consistent depression treatment in VHA patients with DM/D and decreased health care utilization will be attributable in part to improved intermediate diabetes-related outcomes (glycemic and lipemic control). Specific aims and objectives are: Aim 1. Analyze patient and sector of health care (VHA and non-VHA) variations in patterns of guideline-consistent treatment among VHA patients with diabetes and depression (DM/D). Objective 1.1. Identify guideline-consistent depression treatment (both pharmaco- and psycho-therapy) among veterans with DM/D and characterize VHA patients who receive guideline-consistent depression treatment using multivariate models. Objective 1.2. Examine differences between the general medical and mental health specialty sectors in the treatment patterns for depression. Aim 2. Among VHA patients with DM/D, evaluate the impact of guideline-consistent depression treatment on patient-adherence to diabetes care treatments and intermediate outcomes of diabetes care. Objective 2.1. Examine the impact of depression treatment on patient-adherence to antiglycemic and antilipemic medications. Objective 2.2. Determine the effect of guideline-consistent depression treatment on intermediate diabetes outcomes measures, specifically, glycemic and lipemic control. Aim 3. Using longitudinal data, examine the effect of depression on health care utilization and expenditures among VHA patients with diabetes; evaluate the impact of guideline-consistent depression treatment on health care utilization and expenditures in VHA patients with DM/D. Objective 3.1. Estimate and compare health care utilization and expenditures in VHA patients with depression to those without depression. Objective 3.2. Analyze the impact of guideline-consistent depression treatment in VHA patients with DM/D by comparing utilization and expenditures between VHA patients with and without guideline-consistent depression treatment.
METHODS:
We use longitudinal design to examine the relationship between depression care and diabetes care. The study will analyze repeated measurements within each episodes-of-care to support and explain the study findings. Multivariate longitudinal regression techniques are used to examine variation in guideline-consistent depression treatment. Declining effect models are used to analyze the association between guideline-consistent depression treatment and intermediate outcomes and health care expenditures.
FINDINGS/RESULTS:
Although a majority of individuals (60%) received guideline consistent depression treatment (Tiwari et al., In press), our findings suggest opportunities to improve treatment. Diabetes process of care and intermediate outcomes differed by type of mental illness. Despite no differences in glycemic control between individuals with depression and without depression (Banerjea et al., 2008), depression was associated with excess expenditures (Banerjea et al., 2007) with incident depression contributing more to excess costs (Shen et al., 2008). Individuals with guideline-consistent depression treatment have reduced expenditures compared to those without any treatment for incident depression (Tiwari et al., 2007).
IMPACT:
Information on excess costs associated with depression, the relationship between glycemic control and depression, patterns of depression treatment and documented net cost savings associated with treating depression in patients with DM/D helps policy makers can make informed decisions about how to prioritize resource allocation in an era of tight fiscal resources. The proposed study will advance research methods by applying a common unit cost schedule applicable to both VA and non-VA sources of care (VA reasonable Charges) that would reflect differences across patterns of care rather than changes in production efficiencies across the sources for that care.
Implications for Policy, Delivery or Practice:
Our findings suggest that efforts need to be made to promote guide-line consistent antidepressant treatment for depression among those with diabetes will be needed to improve clinical outcomes and capture cost savings.
PUBLICATIONS:
Journal Articles
- Banerjea R, Sambamoorthi U, Smelson D, Pogach LM. Chronic illness with complexities: mental illness and substance use among Veteran clinic users with diabetes. American Journal of Drug and Alcohol Abuse. 2007; 33(6): 807-21.
