Mechanisms Influencing Circadian Blood Pressure Patterns Among Individuals with HIV

Abstract

HIV+ individuals have an increased risk for cardiovascular disease (CVD), but the mechanisms behind this association are poorly understood. While hypertension is a well-established CVD risk factor, clinic-based blood pressure (BP) assessment by itself cannot identify several important BP patterns, including white coat hypertension, masked hypertension, nighttime hypertension, and nighttime BP dipping. These BP patterns can be identified over a 24-h period by ambulatory BP monitoring (ABPM). In this review, we provide an overview of the potential value of conducting ABPM in HIV+ individuals. ABPM phenotypes associated with increased CVD risk include masked hypertension (i.e., elevated out-of-clinic BP despite non-elevated clinic BP), nighttime hypertension, and a non-dipping BP pattern (i.e., a drop in BP of <10 % from daytime to nighttime). These adverse ABPM phenotypes may be highly relevant in the setting of HIV infection, given that increased levels of inflammatory biomarkers, high psychosocial burden, high prevalence of sleep disturbance, and autonomic dysfunction have been commonly reported in HIV+ persons. Additionally, although antiretroviral therapy (ART) is associated with lower AIDS-related morbidity and CVD risk, the mitochondrial toxicity, oxidative stress, lipodystrophy, and insulin resistance associated with long-term ART use potentially lead to adverse ABPM phenotypes. Existing data on ABPM phenotypes in the setting of HIV are limited, but suggest an increased prevalence of a non-dipping BP pattern. In conclusion, identifying ABPM phenotypes may provide crucial information regarding the mechanisms underlying the excess CVD risk in HIV+ individuals.

Low-Salt Diet and Circadian Dysfunction Synergize to Induce Angiotensin II–Dependent Hypertension in Mice

“…29, 30 Moreover, the significance of blood pressure rhythms in human disease is highlighted in human conditions where rhythms are absent, as in non-dipper hypertensive patients 31 that exhibit a raised incidence of cardiovascular morbidity. 32 Moreover, the prevalence of non-dipping blood pressure is not trivial, but may be up to 45% in humans 33 and may even further impact individuals with HIV 34 while targeting non-dipping blood pressure with night-time administration of antihypertensives may even be beneficial in diabetes. 35 …”

Race and sex differences in ambulatory blood pressure measures among HIV+ adults

“…6 For example, infection with the virus disrupts normal circadian rhythms and has been associated with poor sleep quality and sleep disturbances, all factors that have been associated with non-dipping BP. 6, 15 HIV is associated with elevated systemic inflammatory biomarkers, which fail to fully return to normal levels with ART. 5, 6 Excess inflammation has been associated with masked hypertension and non-dipping BP in the general population.…”

“…4 ABPM may be particularly useful for HIV+ adults, as this population has a high psychosocial burden, and a high prevalence of autonomic dysfunction and sleep disturbance. 6 Each of these are risk factors for ABPM phenotypes associated with high CVD risk, including nocturnal hypertension, a non-dipping BP pattern, and masked hypertension. 6 In a recent systematic review, only eight studies of ABPM in HIV+ adults were identified.…”

“…6 Each of these are risk factors for ABPM phenotypes associated with high CVD risk, including nocturnal hypertension, a non-dipping BP pattern, and masked hypertension. 6 In a recent systematic review, only eight studies of ABPM in HIV+ adults were identified. 7 While a high prevalence of nocturnal hypertension and non-dipping BP were present among HIV+ participants, none of these studies included African Americans.…”

“…11 Identifying race and sex disparities in ABPM phenotypes among HIV+ individuals may improve strategies to diagnose and treat hypertension in this high-risk population. 6 In this manuscript, we report race and sex differences in BP phenotypes from a study assessing the feasibility of conducting ABPM among HIV+ adults.…”