NIGHTTIME BLOOD PRESSURE ASSESSED USING HOME MONITORING IN HYPERTENSIVE PATIENTS WITH TYPE 2 DIABETES/PREDIABETES: ASSOCIATION AND AGREEMENT WITH AMBULATORY MONITORING

Abstract

Objective: To investigate the agreement between nighttime blood pressure (BP) measurements using home (HBPM) or ambulatory BP monitors (ABPM) in individuals with hypertension and type 2 diabetes mellitus (DM2) or prediabetes. Design and method: Adults with hypertension (treated or untreated) and DM2 or prediabetes underwent ABPM (measurements at 20 minutes intervals, Microlife WatchBP03) and HBPM (duplicate morning/evening measurements for 7 days, 3 nights with 3 measurements/night, Microlife WatchBP Home-N). Nighttime hypertension was defined as BP >= 120/70 mmHg (systolic/diastolic). Nighttime BP dipping was calculated as the ratio of nighttime BP decline to the daytime levels. Individuals with nighttime BP dip (systolic and/or diastolic) <10% were classified as non-dippers. Results: Data from 113 participants were analyzed (mean age [SD] 65±9.1 years, 67% men, body mass index 30.7±4.8 kg/m2, 84% with DM2, 22% cardiovascular disease, 94% treated hypertension). Average daytime HBPM was 129.2±13.2/73.3±7.8 mmHg and ABPM 126.7±12.1/72.5±7.4 mmHg (systolic/diastolic, p<0.01/p=NS), whilst nighttime HBPM was 115.3±13.1/63.6±7.6 mmHg and ABPM 113.9±13.4/63±7.1 mmHg (systolic/diastolic, p<0.05/p=NS). Strong correlation was observed between HBPM and ABPM levels: daytime r=0.71/0.74 and nighttime 0.86/0.78, systolic/diastolic, p<0.01)]. Good agreement was also found between ABPM and HBPM in diagnosing nighttime hypertension (81%/90%; kappa=0.55/0.70 systolic/diastolic). Among the participants, 32%/31% were classified as non-dippers (HBPM/ABPM, p=NS), with a 74% agreement (kappa=0.41) in detecting non-dippers. Conclusions: These preliminary findings indicate that in individuals with hypertension and DM2 or prediabetes, nighttime BP assessed by a novel home monitor is feasible and shows strong correlation and satisfactory agreement with reference ABPM in detecting nighttime hypertension and non-dipping.