摘要：Objectives . We examined the relationship between continuity of care and diabetes control. Methods . We analyzed data on 1400 adults with diabetes who took part in the Third National Health and Nutrition Examination Survey. We examined the relationship of continuity of care with glycemic, blood pressure, and lipid control. Results . Continuity of care was associated with both acceptable and optimal levels of glycemic control. Continuity was not associated with blood pressure or lipid control. There was no difference between having a usual site but no usual provider and having a usual provider in any of the investigated outcomes. Conclusions . Continuity of care is associated with better glycemic control among people with diabetes. Our results do not support a benefit of having a usual provider above having a usual site of care. Diabetes mellitus is a common and potentially disabling chronic disease. 1, 2 People with diabetes are at increased risk for a number of complications, including retinopathy, renal disease, and heart disease. High-quality medical care has been shown to reduce these complications among patients with diabetes. 3 The American Diabetes Association (ADA) has recommended monitoring diabetes and its complications through the use of periodic tests as well as appropriate management once complications are identified. 4 However, recent data suggest that a gap exists between recommended diabetes care and the care patients actually receive. 5 Continuity of care has been shown to have positive benefits, including increased likelihood of cancer screening, 6 better communication between patients with chronic disease and their physicians, 7 and increased patient adherence with follow-up appointments. 8 Provider continuity could have a positive impact on quality of care and outcomes because of the long-term relationship and concomitant accrued knowledge that develop between a patient and a provider. 9 There is some disagreement regarding whether having a usual site of care but no usual provider is equivalent to having a usual provider. The United States Institute of Medicine and the British General Medical Services Committee have made little distinction between continuity with a team of providers and continuity with a regular provider. 10, 11 However, having a usual site of care may not be equivalent to having a regular provider in terms of benefits. One study demonstrated that patients at high levels of continuity with a provider had a decreased likelihood of future hospitalizations relative to patients with a usual site but no usual provider. 12 In another study, a generally linear trend was found in breast and cervical cancer screening rates when moving from the presence of no usual source of care to the presence of a usual care site and the presence of a usual provider at that care site. 6 Few studies have focused on the impact of continuity of care on diabetes control, and the limited data available have indicated mixed results. 13, 14 One recent study conducted in 5 community health centers on the US–Mexico border among a primarily Hispanic population revealed that continuity with a provider was associated with better glycemic control. 15 However, this study assessed continuity only among providers at the clinic, thereby excluding visits made to providers outside the clinic. All patients were therefore assumed to have continuity with a site. Thus, the difference between having a usual site of care and having a usual provider has not been studied in terms of its impact on diabetes control and related chronic conditions such as hypertension and hyperlipidemia. As a result, the objective of this study was to examine, in a national sample of adults with diabetes, the effect of continuity with a site versus continuity with an individual provider on control of diabetes and control of associated chronic conditions.
