Evaluation of self-monitoring of blood pressure in the PERHIT study and the impact on glomerular function.

BACKGROUND Although intensive blood pressure (BP) control has not been shown to slow the progression of chronic kidney disease (CKD), intensive BP control has been shown to reduce the risk for adverse cardiovascular outcomes in the CKD population. The aim of this post-hoc study was to study the interplay between a self-monitoring BP system and glomerular function. METHODS In all, 949 participants with hypertension underwent visits at baseline, after eight weeks and 12 months. Half of the participants received a BP monitor and installed a program on their mobile phone. During eight weeks, they measured daily and reported their BP values. RESULTS Within the intervention group, BP and systolic BP (SBP) decreased from baseline to eight weeks and 12 months (p < .001). Pulse pressure (PP) and mean arterial blood pressure (MAP) decreased from baseline to eight weeks (p = .021 and p = .004) vs 12 months (p = .035 and p = .008). Within the control group, a decrease was observed from baseline to 12 months for SBP, diastolic BP (DBP) and PP (p = .025, p = .023 and p = .036). In the intervention group, we observed an association between a decrease in SBP, DBP, PP and MAP and a decrease in eGFR (estimated glomerular filtration rate), (p < .001, p < .001, p = .013 and p < .001). In the control group, similar results were observed for PP only (p = .027). Within the intervention group, eGFR decreased (p < .001) but within the control group, the decrease was non-significant (p = .051). CONCLUSION We observed an association between a decrease in all BP components and eGFR decline within the normal range in the intervention group but not in the controls. TRIAL REGISTRATION The study was registered with ClinicalTrials.gov [NCT03554382].