Busier Docs Provide Lower-Quality Diabetes Care, Unless They Treat Many Diabetics

People with diabetes treated by primary care providers (PCPs) with a high patient volumes experienced worse management of their disease. However, if a physician specifically treated a higher number of diabetics, the quality of the diabetes care received by patients was significantly higher.

Prior research has demonstrated a link between increased volume and better outcomes in surgical settings and hospitals, but not many studies have investigated whether this relationship holds true for chronic disease management in primary care. On the one hand, physicians may accumulate more experience when they treat a higher volume of patients, but on the other, this influx of patients may reduce the amount of time they can spend managing each patient’s condition.

Researchers thus set out to determine the associations between quality of diabetes care and both overall patient volume and diabetes-specific volume in primary care practices. Their findings were published in the Annals of Internal Medicine.

The cohort study analyzed administrative data for over 1 million patients with diabetes assigned to 9014 PCPs in Ontario, Canada. These physicians were stratified by their overall ambulatory volume of patients per day and their number of patients with diabetes. The patient indicators for the quality of diabetes care were appropriate disease monitoring and testing, such as eye exams or glycated hemolgoblin (A1C) tests; prescription of diabetes-management medications; and adverse clinical outcomes, defined as emergency department visits for hypoglycemia or hyperglycemia.

Patients of physicians with higher overall volumes had lower rates of appropriate screening and testing and were less likely to fill their prescriptions for diabetes-controlling medications than the patients of physicians with lower volume. There was no statistically significant association between overall patient volume and emergency visits related to diabetes.

Higher diabetes-specific patient volume, however, was related to higher quality diabetes care. The patients treated by physicians with a larger diabetic patient base had higher rates of testing and more prescriptions filled, as well as lower rates of emergency visits for hypoglycemia or hyperglycemia.

These associations were not explained by cardiovascular comorbidity or socioeconomic status among the patients or by the physician payment model, the researchers found. There was also no relationship found between physician volume and non-diabetes indicators like hip fracture, proving that the findings were specific to diabetes care.

Furthermore, they noted that the magnitude of the disparity in care between the physicians was significant. “If all primary care physicians had achieved the same rate of eye examinations as those with the lowest overall ambulatory volume, more than 25,000 additional patients would have had an examination,” they wrote.

The findings of the study have “important implications for both future research and health system planning,” the authors concluded. “Future policies to improve quality of diabetes care may offer peer support and mentoring, point-of-care support, or enhanced specialty—primary care interactions to primary care physicians with low diabetes-specific volume.”