PS-C12-12: EFFECT OF CHRONOTHERAPY ON BLOOD PRESSURE VARIABILITY IN HYPERTENSIVE AND CHRONIC KIDNEY DISEASE ADULT PATIENTS IN NIGERIA

Abstract

Background: Blood pressure is synchronized predictably with the circadian activity-rest cycle. Few available studies have shown that chronotherapy may improve blood pressure variability (BPV) among hypertensive and chronic kidney disease patients. Empirical evidence is lacking among Nigerians. Objective: This study ascertained the effect of chronotherapy (taken as the use of antihypertensive medications at bedtime) on BPV of adult patients aged 18 years and above diagnosed with hypertension (control) and chronic kidney disease (CKD) using ambulatory blood pressure monitoring over three months follow up. Design and method: We conducted a retrospective analysis of data of respondents included in the Ibadan Ambulatory Blood Pressure Registry (IABPR) at the University College Hospital, Ibadan, Nigeria. Sociodemographic characteristics, lifestyle habits, and anthropometric measurements were obtained. Paired t-test was used to test the differences in the mean BP parameters before and after the study at p 0.05. Results: There were 52 respondents, 24 hypertensive controls (mean age 58.6 ± 11.3years) and 28 CKD patients (mean age 45.2 ± 11.1years). The hypertensive controls had significantly reduced mean systolic, diastolic, and arterial BP at the end of the study. Similarly, the wake-up and sleep periods mean systolic, diastolic, and arterial BP decreased significantly among the hypertensive controls. However, the CKD patients showed no significant BP variability with chronotherapy at the end of the study. Both the hypertensive controls and CKD patients experienced no significant BP dipping during the study period. Conclusion: Hypertensive patients in our study experienced a significant reduction in their BP parameters with chronotherapy, while CKD patients showed no significant changes in their BP. Further studies are needed in Nigeria to determine the beneficial effects of chronotherapy in this population.