Background: Quality-of-care assessment at a single visit can be affected by whether a patient's comorbid conditions are related or unrelated to a specific measure.
Objective: To examine the association of unrelated comorbid conditions with treatment of uncontrolled hypertension in primary care visits.
Design: Examination of a database derived from electronic medical records collected during routine care of a cohort of primary care patients.
Setting: 6 primary care practices in Philadelphia, Pennsylvania.
Patients: 15,459 patients with uncontrolled hypertension who made 70,557 visits to 200 clinicians from January 2004 through December 2006.
Measurements: Intensification of any antihypertensive treatment before the next visit was assessed. Patient and clinician information were obtained from electronic medical records and administrative data. Unrelated comorbid conditions included 28 conditions, such as arthritis and emphysema, whereas related comorbid conditions included vascular diseases. Generalized estimating equation logistic regression models were used to adjust for patient, health care, and provider characteristics and for clustering. Variation in the effect of unrelated comorbid conditions was examined at the visit, patient, and provider level.
Results: At study visits, patients had a mean of 2.2 (SD, 1.8) unrelated comorbid conditions. The adjusted odds of treatment intensification decreased with the number of unrelated comorbid conditions, from 0.85 (95% CI, 0.80 to 0.90) for 1 to 0.59 (CI, 0.51 to 0.69) for 7 or more versus none. The relationship between treatment intensification and unrelated comorbid conditions persisted at the visit, patient, and provider levels (P < 0.001).
Limitations: The reasons for not intensifying treatments are unknown. The recorded blood pressure may be inaccurate. Physicians may vary in their recording of comorbid conditions.
Conclusion: Patients with more unrelated comorbid conditions were less likely to have uncontrolled hypertension addressed at a visit. The effect of different types of comorbid conditions on meeting quality-of-care measures merits further investigation.