Short–run Associations Between Medical Care Expenditures and Adherence to Clinical Practice Guideline-based Measures for Diabetes

To estimate relationships between medical care expenditures in 1996 and adherence to seven guideline-based measures for diabetes. Nonlinear exponential regression analyses were used to estimate relationships between medical care expenditures in 1996 and adherence to guideline-based measures that year, adjusting for differences in patients' demographics, location, plan type, and severity of illness. Adherence to criteria regarding physician visits, eye exams, blood sugar tests, urinalysis, triglyceride tests, total cholesterol tests, and HDL cholesterol tests was studied for 18,403 patients in 35 health plans. Average total medical expenditures would be $713 higher if all patients were treated according to the guideline-based measures in 1996, compared to what expenditures would be if no patients were treated that way. Average diabetes-related expenditures would be about $322 higher. Two important exceptions to this pattern were for adherence to the suggested frequency of hemoglobin A1c blood sugar tests and ophthalmology visits for dilated eye exams. Having the recommended number of these tests was associated with significantly lower total expenditures. In general, adherence to clinical practice guideline-based measures was more costly than deviating from those criteria, in the short-run. Perhaps expenditures should be higher for many patients who are not treated according to guidelines. Randomized studies with more years of follow-up should be conducted to assess whether short-term investments in guideline adherence pay off with lower medical expenditures and greater levels of health in the long term.