Blood pressure phenotype reproducibility in CKD outpatients: a clinical practice report

Out-of-office blood pressure (BP) measurement is encouraged by recent hypertension guidelines for assessing BP phenotypes. These showed acceptable reproducibility in the short term, but few data exist about long-term reproducibility, particularly for chronic kidney disease (CKD) patients. We evaluated changes of the BP phenotypes at 6 and 12 months in 280 consecutive non-dialysis CKD outpatients (186 males, age 71 ± 12 years, eGFR 38 ± 13 ml/min/1.73), without any change in drug therapy. Elevated BP is defined as office BP > 140/90 and home BP > 135/85 mmHg for defining the following BP phenotypes: sustained uncontrolled hypertension (SUCH); white-coat uncontrolled hypertension (WUCH); masked uncontrolled hypertension (MUCH); and controlled hypertension (CH). At baseline, the prevalence of the phenotypes was SUCH 36.6%, CH 30.1%, WUCH 25.4% and MUCH 7.9%, and it was similar at 6 months and 12 months. On the other hand, individual phenotype reproducibility at 12 months was poor both overall (38.0%) and across the different phenotypes (SUCH 53.9%, WUCH 32.4% and CH 32.1%, MUCH 9.1%). Patients who were not maintaining the same phenotype (non-concordant) were not distinguished by age, sex, BMI, eGFR, presence of diabetes or cardiovascular disease, or pharmacological therapy. When reproducibility of BP phenotypes both at 6 months and at 12 months was assessed, it was very low (19.6%), particularly for MUCH (0%), CH (14%) and WUCH (15.5%), while it was 31% for SUCH. In a CKD cohort, the overall prevalence of the different BP phenotypes defined by office and home BP remains constant over time. However, only 38% of patients maintained the same phenotype at 12 months, suggesting a poor reproducibility over time for the BP phenotypes.