DIAGNOSTIC PERFORMANCE OF PRE-DIALYSIS AND AMBULATORY BLOOD PRESSURE LEVELS IN MEN AND WOMEN HEMODIALYSIS PATIENTS

Abstract

Objective: Ambulatory-blood-pressure (BP) control is worse in men than in women with chronic kidney disease or kidney transplantation. So far no study assessed in parallel possible effects of sex differences on the prevalence, control, and BP phenotypes according to pre-dialysis and 48-h ABPM in hemodialysis patients. Further, no study has evaluated the diagnostic accuracy of pre-dialysis BP in men and women hemodialysis patients. Design and method: 129 male and 91 female hemodialysis patients that underwent 48-h ABPM with Mobil-O-Graph-NG were included in this analysis. Hypertension was defined as follows: (1)pre-dialysis BP greater than or equal to 140/90mmHg or use of antihypertensive agents, (2)48-h BP greater than or equal to 130/80mmHg or use of antihypertensive agents. Results: The prevalence of hypertension was not different between men and women with the use of pre-dialysis BP (92.2% vs 92.3%, p = 0.987, respectively) or 48-h ABPM (92.2% vs 89%, p = 0.411). With the use of pre-dialysis BP men had significantly lower control rates than women (18.5% vs 32.1%, p = 0.025); a similar pattern of worse control in men was apparent with ABPM, but the difference was not statistically significant (22.7% vs 28.4%, p = 0.360). The rate of patients with concordant lack of control by pre-dialysis and ABPM was significantly higher in men than women (65.3% vs 49.4%, p = 0.023); white-coat (14.9% vs 17.6%, p = 0.593) and masked hypertension (10.7% vs 18.8%, p = 0.101) did not differ between-groups. However, the misclassifation rate with the use of pre-dialysis BP was lower in men than women. There was moderate or at best fair agreement between pre-dialysis and ABPM with regards to the prevalence (men: kappa-statistics = 0.39, p < 0.001 and women: 0.27, p = 0.011) and control rates (kappa-statistics = 0.25, p = 0.005 and 0.17, p = 0.124, respectively). Pre-dialysis BP greater than or equal to 140/90mmHg had sensitivity/specificity of 85.9%/51.4% in men and 72.4%/54.5% in women for the diagnosis of elevated 48-h BP. Receiver-operating-curve analyses confirmed this poor diagnostic performance. Conclusions: The prevalence of hypertension is similar between men and women hemodialysis patients but men have worse rates of office BP control. The diagnostic accuracy of pre-dialysis BP was equally poor in men and women hemodialysis patients.