Factors influencing the frequency of visits by hypertensive patients to primary care physicians in Winnipeg.

BACKGROUND: As part of a recent project focused on needs-based planning for generalist physicians, the authors documented the variety of practice styles of primary care physicians for managing patients with hypertension. They investigated the validity of various explanations for these different styles and the relative contributions of physician and patient characteristics to the rates at which hypertensive patients contact physicians.
METHODS: Retrospective descriptive study using regression analyses to simultaneously adjust for the influence of key patient and physician characteristics. Hypertensive patients in Winnipeg were identified using Manitoba physician claims data for fiscal years 1993/94 and 1994/95. Patients were included if they were 25 years of age or more and had at least one physician contact in both 1993/94 and 1994/95 during which hypertension was diagnosed. In addition, the primary care physician had to be the physician that the patient contacted most frequently in 1993/94 and 1994/95 and with whom she or he had at least 2 visits during this period. Only patients of family practitioners whose practice included at least 50 hypertensive patients were included.
RESULTS: To control for the effects of large samples and to validate the results, the authors conducted all analyses for half (6282) the sample of hypertensive patients who met the study criteria (12,563). A total of 132 primary care physicians who met the study criteria were identified. The patients made on average 9.3 ambulatory visits to physicians (both general practitioners and specialists) in 1994/95. Those who had more complex medical conditions (i.e., were formally referred to a specialist), those who had 3 or more serious medical problems and those who had been admitted to hospital made more visits to their primary care physician than those without these characteristics. After these and other key patient characteristics were controlled for, a primary care physician's patient recall rate in 1993/94 was strongly related to the number of visits his or her hypertensive patients made to all doctors for any reason in 1994/95. Physicians with high patient recall rates (i.e., who saw their hypertensive patients on average 8 or more times) in 1993/94 also had high recall rates in 1994/95.
INTERPRETATION: Because patient characteristics most strongly associated with high visit rates were those reflecting patient illness, policy measures aimed at patients (e.g., user fees and deinsurance) do not appear to be the appropriate policy tool for dealing with high visit rates. Given the influence of a physician's patient recall rate on patient visit patterns, physician profiling and feedback may prove more appropriate.