Creatine kinase as predictor of blood pressure and hypertension. Is it all about body mass index? A follow-up study of 250 patients.

Abstract

The correlation between creatine kinase (CK) and blood pressure (BP) was examined prospectively in 120 patients with persistent high CK and 130 individuals with normal CK. Hypertension was defined as systolic BP (SBP) ≥ 140 mm Hg or diastolic BP (DBP) ≥ 90 mm Hg or current use of antihypertensive medication. Baseline CK was weakly correlated with SBP (r = 0.11, P = .07) and DBP (r = 0.16, P = .01) at follow-up. Persons with persistent high CK had higher SBP (140.8 mm Hg vs 138.2 mm Hg) and DBP (83.2 mm Hg vs 81.0 mm Hg, P = .06) values and were more likely to have hypertension (66.7% vs 55.5%, P = .05) than individuals with normal CK. In age- and sex-adjusted analysis, a 1-unit change in logCK was associated with a 4.9-mm Hg higher SBP, a 3.3-mm Hg higher DBP, and a 2.2-higher odds for having hypertension at follow-up (P = .1, .07, and .06, respectively). When including body mass index (BMI) to the model, BMI was a strong and independent predictor for SBP, DBP, and hypertension at follow-up and the CK effect on blood pressure was substantially attenuated. This study showed that the CK effect on blood pressure is clearly modified by BMI.