Clinical Significance of Nighttime Blood Pressure: Exploring the Association of Nocturnal Hypotensive Phenotype and History of Falls in Elderly Hypertensive Patients

Objective: falls are a major health problem in elderly, approximately 28–35% of individuals aged > 65 years’ experience falls each year. Previous studies suggested that unexplained falls may mask a syncope or pseudo-syncope in almost 50% of cases, and that patients with reflex syncope have a higher prevalence of systolic blood pressure (SBP) drops on ambulatory blood pressure monitoring (ABPM), the so-called hypotensive phenotype. However, it is not clear whether hypotensive phenotype may be itself associated with falls. We investigate if hypotensive phenotype is associated with history of falls in elderly hypertensive. Design and method: a cross-sectional study that included treated hypertensive patients aged >=75 years evaluated at the Hypertension Center of Istituto Auxologico Italiano IRCCS in Milan. We excluded patients with a life expectancy of less than 6 months. All participants underwent ABPM. History of falls within the last year was recorded and multidimensional geriatric assessment to estimate frailty using Frailty accumulation index was performed. Daytime and night-time hypotensive phenotypes were defined as at least one SBP drops <90 mmHg on ABPM during daytime and night-time, respectively. The same analysis was repeated by considering cut-off of SBP <80 mmHg both during day and night-time. Results: we enrolled 105 patients, mainly females (n=80, 76%) with a mean age of 82 (± 4) years. In 74 (70%) patients day-time hypotensive phenotype was present at ABPM, while nighttime hypotensive phenotype was present in 24 of them (23%). Among participants 21 (20%) experienced a fall in the last 12 months; compared for age, sex, BMI, frailty index and BP patients with falls and not have no significant differences. Regardless of SBP cut-off, nocturnal hypotensive phenotype was associated with history of falls while daytime hypotensive phenotype was not. (Figure 1). Conclusions: In our study, nighttime but not daytime BP drops were associated with falls in treated hypertensive elderly patients. The mechanistic role of nighttime hypotensive phenotype and its association with syncope and falls will need to be evaluated in larger prospective studies to better clarify the utility of ABPM in falls prediction in elderly.