Isolated nocturnal hypertension in patients living with human inmunodeficiency virus (hiv)

Introduction: People living with HIV (PLHIV) have higher rates of cardiovascular events compared to the general population; however mechanisms behind this discrepancy are poorly understood. High prevalence of hypertension has been proposed as a mechanism underlying cardiovascular events with contradictory results when office blood pressure (BP) is considered. Ambulatory blood pressure measurements (ABPM) have the advantage to measure BP during sleep, a cause of masked hypertension. Additionally, body weight and electrolytes disturbances are common in PLHIV under antiretroviral and antibiotic therapy. We aim to describe the prevalence of isolated nocturnal hypertension (INH) and it characteristics in PLHIV. Material and methods: A random sample of PLHIV from the provincial HIV program in Cordoba, Argentina, underwent clinical and laboratory examination, and 24 h ABPM. Nocturnal hypertension (NH) was defined as nocturnal systolic BP ≥ 120 mmHg and or nocturnal diastolic BP≥70 mmHg. INH was defined in those patients with NH with daytime systolic and diastolic BP< 135/85 mmHg respectively. Results: PLHIV were included in the study: 60% male, mean age was 44.6 (27–69) years old, 87% were receiving antiretroviral therapy. BMI was 25.8 ± 4.8, mean CD4 count was 404.4 ± 289, cells/ml and 86.2% were virologically suppressed. The prevalence of NH was 48.5% [95%CI:36–60%], the vast majority having INH 29/32 (90%), thus the population prevalence of INH was 43.9% [95%CI:32–55,%]. INH patients have an excess of 10.4 and 8 mmHg in 24 hr systolic BP and diastolic BP respectively compared to no INH patients (both p < 0.001). No differences were found regards age, sex, viral load, CD4+ cells and years of HIV history between patients with and without INH. Multiple linear regression (adj-R2 = 0.27, p < 0.001) adjusted by sex and age determined that BMI (β = 0.79, p = 0.02]), plasma uric acid (β = 0.33, p = 0.01) and plasma potassium (β = -9.5, p = 0.03]) independently predicted nocturnal systolic BP in PLHIV. In a multiple logistic regression model adjusted by age and sex, BMI≥30 was associated with INH (OR 4.04 [95%CI: 1.25–13) Conclusion: INH is highly prevalent in PLHIV conferring an excessive hypertension load that may explain the associated high CVS risk. Obesity, increased uric acid, and low plasma potassium are associated with nocturnal systolic BP. Our work suggests the routine use of ABPM and explore metabolic disturbances in obese PLHIV.