A similar pattern prevails when using the core diabetes quality index in a multiple linear regression (not tabled). Study variables explain 18.18% of the variance in the index value. All 4 of the rural residential variables were statistically significant; patients living in remote large rural areas had a greater likelihood of receiving the recommended tests after controlling for potential confounders, while patients living in other types of rural areas were less likely to receive the tests.
Discussion
The quality of outpatient care for elderly persons with diabetes leaves much to be desired.10-12,15 On a national level, only 21% of patients received a glycated hemoglobin determination in 1994, perhaps the best single summary of diabetic control available to physicians.10,11 In our study of Washington for the same year, a much higher proportion of patients received this test, suggesting the existence of major regional differences. Yet even in our study, almost half of patients with a diagnosis of diabetes did not receive a glycated hemoglobin determination even though Medicare reimburses separately for this test. Only 27.5% received all 3 of the tests recommended by authoritative national organizations during the study year.
The location of the patients’ community affects their likelihood of receiving the recommended screening tests. Patients living in large rural communities remote from cities were significantly more likely to receive the recommended services than their urban counterparts; patients living in other rural locations were less likely to receive these services.
What might explain these findings? One contributing factor is the relative unavailability of endocrinologists in many rural communities. Rural patients who saw an endocrinologist at least once during the year were almost twice as likely to have had a glycated hemoglobin determination, probably because ordering such a test is part of the routine when endocrinologists see a new patient with diabetes.16 Only 24.6% of the visits to an endocrinologist occurred within the rural area where the patient lived, since most endocrinologists practice in urban areas. It is likely that this access barrier explains the much lower rate at which rural patients see endocrinologists and contributes to the lower rate of appropriate testing.
But this is not the only factor. There are very few endocrinologists in the state of Washington (69 in our study), and most diabetic care is provided by primary care physicians.17 The highest rate of guideline adherence occurs in large remote rural communities—communities that have endocrinologists but where the rate at which patients visit these specialists is still less than half of that in urban communities. It may be that large rural towns represent the best of both worlds: vibrant, rapidly growing communities with an adequate supply of both generalist and specialist physicians that serve as regional referral centers for surrounding rural towns.
Limitations
These data are based on the elderly Medicare population in Washington who are not members of managed care organizations. Managed care penetration in 1994 was relatively low (12% of the entire population), but was higher in urban than in rural areas. With the increased attention that managed care pays to adherence to guidelines, it is possible that the true rate of urban compliance is higher than we reported. The rates in rural areas would be little affected by this limitation. Patterns of care may also be different for younger people, irrespective of insurance coverage. Care may also have improved since 1994.
Also, Medicare’s data systems are primarily mechanisms to ensure accurate billing and payment; they were not designed as research tools. However, previous work by Weiner and colleagues12 shows that the Medicare data were of generally good quality. Finally, our study relied entirely on process of care as a surrogate for medical care quality. Although there is general consensus that the process measures studied here are desirable in the care of patients with diabetes, we do not know whether patients who received these tests had better outcomes.
Conclusions
The results of our study demonstrate that the quality of care received by Medicare patients in Washington in 1994 was better in some important respects than that received in other parts of the country. Although there is still significant room for improvement, the fact that there is marked regional variation suggests that physicians can make meaningful improvements in the quality of care.18,19 It would be useful to identify specific communities where quality of care indicators were suboptimal and design educational efforts for patients and care providers. Perhaps using Medicare data to provide physician scorecards would improve adherence.
Adherence to quality standards was not uniform across rural communities. Rural communities in counties adjacent to metropolitan areas had significantly lower quality-of-care measures than people living in nearby urban areas. Perhaps there are unmeasured socioeconomic or medical practice factors among these populations that explain this lower level of adherence to established standards, even after correcting for the confounding variables that we were able to measure. It would be worth embarking on a systematic exploration of the clinical, social, and organizational factors that led to this relatively substandard experience that has been noted for other defined populations.20