This is the first in the literature to examine quality of diabetes care in a national sample of Medicaid enrollees, and the first to examine how quality in that sample differs between individuals with and without mental disorders. Several findings are notable. First, quality was low across the entire sample of enrollees. Second, mental comorbidity was associated with even lower compliance with HEDIS measures and elevated rates of hospitalization for Ambulatory Sensitive Conditions. Finally, among the population with comorbid mental and medical conditions, a number of county and state-level factors, many amenable to policy intervention, were associated with improved quality of care.
Across this national sample of Medicaid enrollees, rates of performance on the HEDIS diabetes measures was very low – considerably lower than in other insurers and populations. In the current study, rates of compliance with all HEDIS measures except having an eye exam, as well as the likelihood of being compliant with at least 2 measures, was below 50%. Both in commercial plans (36
) and in Medicare (37
), rates of compliance across the HEDIS diabetes measures are approximately twice as high as those seen in this Medicaid sample. High rates of ACSC hospitalizations are important cost drivers for diabetes. (38
Quality of diabetes care for enrollees with mental comorbidities was even lower than quality in the general sample of Medicaid enrollees, both with regards to performance on HEDIS indicators and in likelihood of ACSC admission. A series of patient, provider, and system-level factors are likely responsible for these quality deficiencies among persons with mental disorders.(39
) Poverty (40
) low health literacy(42
), and social factors (44
) may raise challenges to compliance with treatment for Medicaid populations in general and even worse care for those with mental disorders. For providers, competing demands for time and attention may limit their willingness and ability to care for comorbidities. (46
) Finally, at a system level, lack of coordination and delivery of care across multiple locations may lead to challenges in coordination and potential duplication of services.(1
) Improving quality of care for persons with comorbid conditions within Medicaid will require attention to each of these patient, provider, and system-level issues.
The individual-level variables found to predict worse quality of care are generally not amenable to change, but nonetheless can help identify populations at risk for poor quality of care among persons with comorbid conditions. For instance, African Americans were at elevated risk both for lower performance on HEDIS measures and elevated rates of inpatient ACSC admissions. These subpopulations may be particularly important targets for quality improvement efforts designed to improve quality and efficiency of care for persons with comorbid conditions.
Several provider-level factors were associated with quality of diabetes care for individuals with comorbid conditions. Persons living in primary care shortage areas had worse performance on HEDIS diabetes quality measures. At a state-level, better Medicaid reimbursement rates for physicians were associated with improved performance on both measures. Taken together, these findings suggest the potential importance of an adequate primary care workforce, as well as adequate reimbursement for those providers, in ensuring quality of diabetes among persons with comorbid medical and mental conditions. In addition to adequate funding, other studies have suggested that targeted financial incentives may also help reduce inequities in medical treatment.(48
Enrollees in states with higher levels of mental health funding for mental health services had better performance on HEDIS measures and also reduced use of ambulatory care specific inpatient admissions. This finding was unexpected, given that mental health funding reimburses mental health rather than medical services, and largely is used to pay for services for uninsured clients. Given that the same providers and safety net facilities typically manage both uninsured and Medicaid recipients, it is possible that these added resources spill over to improve care for these clients. More research is needed to understand the link between mental health funding and outcomes in individuals with comorbid conditions.
The findings should be interpreted in the light of several limitations. First, the study did not include managed care claims or dually-eligible clients, and the findings should be extrapolated to other Medicaid populations, particularly those eligible due to low income, with caution. Second, as in any claims-based diagnosis, cases only represent those recognized and billed for under Medicaid. Given that mental disorders are commonly underdiagnosed and undertreated, the prevalence and population-based impact of mental disorders on diabetes care are likely substantially larger than those reported in the study.
These limitations notwithstanding, the findings suggest that mental disorders are important risk factors for poor quality of diabetes care in among Medicaid recipients in the United States. With the looming expansion of Medicaid under health reform, it will be important to track quality of care and develop clinical and policy-level strategies to improve quality of care in this vulnerable population.