BMI, annual blood pressure measurements, and mortality in patients with obesity and hypertension: a retrospective cohort study

Background/Objectives In-clinic blood pressure measurement is recommended annually for all hypertensive individuals, but can be difficult to perform in obese patients. We aimed to examine a population-based cohort of obese hypertensive patients to determine whether: (a) BMI was inversely associated with annual blood pressure measurement and (b) performing annual blood pressure measurements was associated with reduced mortality independent of BMI. Patients/Methods We carried out a retrospective cohort analysis in 4972 obese hypertensive patients from UK primary care. Multivariable binary logistic regression was used to examine the association between obesity class (class 1 = BMI 30-34.9; class 2 = 35.0-39.9; class 3 = 40 kg/m(2) or greater) and annual blood pressure measurement. An accelerated failure time multivariable model was used to examine the association between annual blood pressure measurement and mortality. Results The mean age of the patients was 52.3 +/- 9.6 years, the mean BMI was 34.1 +/- 4.8 kg/m(2), and the median follow-up was 13.5 (interquartile range 6.8-20.3) years. A total of 519 (10.4%) patients died. Annual blood pressure measurements were performed in 1605 (47.0%) patients with class 1, 429 (40.2%) with class 2, and 198 (41.1%) with class 3 obesity (P < 0.001). Compared with class 1, the covariate-adjusted odds of annual blood pressure measurement was 0.85 [95% confidence interval (CI) 0.73-0.98] for class 2 and 0.87 (95% CI 0.71-1.07) for class 3. Annual blood pressure measurement was associated with an 18.9% (95% CI 9.4-28.3) increase in survival. Conclusion Less than 50% of obese hypertensive patients underwent annual blood pressure measurements and measurements were less frequent in severely obese patients. Annual blood pressure measurement was associated with increased survival. Strategies to improve measurement frequency in obese patients should be implemented. Copyright (C) 2015 Wolters Kluwer Health, Inc. All rights reserved.