Central/Peripheral Fat Mass Ratio Is Associated With Increased Risk of Hypertension in HIV-Infected Patients

HIV-Associated Hypertension: Risks, Mechanisms, and Knowledge Gaps

HIV type 1 (HIV-1) is the causative agent of AIDS. Since the start of the epidemic, HIV/AIDS has been responsible for ≈40 million deaths. Additionally, an estimated 39 million people are currently infected with the virus. HIV-1 primarily infects immune cells, such as CD4+ (cluster of differentiation 4+) T lymphocytes (T cells), and as a consequence, the number of CD4+ T cells progressively declines in people living with HIV. Within a span of ≈10 years, HIV-1 infection leads to the systemic failure of the immune system and progression to AIDS. Fortunately, potent antiviral therapy effectively controls HIV-1 infection and prevents AIDS-related deaths. The efficacy of the current antiviral therapy regimens has transformed the outcome of HIV/AIDS from a death sentence to a chronic disease with a prolonged lifespan of people living with HIV. However, antiviral therapy is not curative, is challenged by virus resistance, can be toxic, and, most importantly, requires lifelong adherence. Furthermore, the improved lifespan has resulted in an increased incidence of non-AIDS-related morbidities in people living with HIV including cardiovascular diseases, renal disease, liver disease, bone disease, cancer, and neurological conditions. In this review, we summarize the current state of knowledge of the cardiovascular comorbidities associated with HIV-1 infection, with a particular focus on hypertension. We also discuss the potential mechanisms known to drive HIV-1-associated hypertension and the knowledge gaps in our understanding of this comorbid condition. Finally, we suggest several directions of future research to better understand the factors, pathways, and mechanisms underlying HIV-1-associated hypertension in the post-antiviral therapy era.

Hypertension among persons living with HIV/AIDS and its association with HIV-related health factors

BACKGROUND

Human Immunodeficiency Virus (HIV) infection remains a public health concern in many countries. The increased life expectancy in the post-Antiretroviral Therapy (ART) era has led to an increased risk of cardiovascular disease and death among Persons Living with HIV (PLHIV). Hypertension remains a significant risk factor for cardiovascular disease among PLHIV. Some studies have suggested associations between hypertension among PLHIV and HIV-related health factors.

OBJECTIVE

To determine the prevalence of hypertension among PLHIV on antiretroviral medications and examine its association with HIV-related health factors.

METHODS

A cross-sectional study was conducted among attendants at an adult HIV clinic. 362 study participants were selected by systematic sampling. Data on hypertension diagnosis, HIV-related health factors, sociodemographic and other traditional cardiovascular risk factors were collected using a standardized questionnaire and patient chart review. Multivariate logistic regression model was used to determine the association between hypertension and HIV-related factors, adjusting for other risk factors for hypertension.

RESULTS

The mean age of participants was 47.9 years and majority of participants were female (77.1%). 42% of study participants had been on antiretroviral medications for > 10 years. The prevalence of hypertension was 17.4%. Age > 50 years was associated with higher odds of hypertension (aOR: 3.75, 95%CI 1.68, 8.55, p-value: 0.002). BMI in overweight and obese categories, and a history of comorbid medical conditions (diabetes, hyperlipidemia) were also associated with higher odds of hypertension (aOR: 3. 76, 95%CI 1.44, 9.81, p-value: 0.007), (aOR: 3.17, 95%CI 1.21, 8.32, p-value: 0.019) and (aOR: 14.25, 95%CI 7.41, 27.41, p-value: < 0.001) respectively. No HIV-related health factors were associated with hypertension.

CONCLUSION

Hypertension was a common condition among PLHIV on antiretroviral medications. No HIV-related health factors were associated with hypertension. Traditional risk factors associated with hypertension were increased age > 50 years, increased BMI, and a history of comorbid medical conditions.

Sleep-Disordered Breathing and Prevalent Hypertension in Men With and Without HIV

BACKGROUND

Sleep-disordered breathing (SDB) is a known risk factor for hypertension. Despite the well-established link between HIV infection and hypertension, it remains to be determined whether HIV infection modifies the association between SDB and hypertension.

SETTING

The Multicenter AIDS Cohort Study.

METHODS

SDB was assessed using in-home polysomnography in 779 men (436 with and 343 without HIV). The apnea-hypopnea index (AHI) based on oxyhemoglobin desaturation threshold of ≥3% or arousal (AHI 3a ) and ≥4% (AHI 4 ) along with oxygen desaturation index (ODI) were used to quantify SDB severity. Hypertension was defined as a blood pressure ≥140/90 mm Hg, use of antihypertensive medication, or self-report of a clinical diagnosis. The associations between HIV, SDB, and hypertension were characterized using multivariable logistic regression.

RESULTS

The prevalence of hypertension and SDB (AHI 3a ≥ 5 events/hr) was high, with estimates of 53.8% and 82.8%, respectively. Among men without SDB, HIV was independently associated with hypertension, with an adjusted odds ratio (OR) of 3.05 [95% confidence interval (CI): 1.33 to 7.01]. In men without HIV, SDB was associated with hypertension (OR: 2.93; 95% CI: 1.46 to 5.86). No significant increase in the odds of hypertension was noted in men with both HIV and SDB compared with men with either factor alone, with an OR of 3.24 (95% CI: 1.62 to 6.47). These results were consistent across different measures used to define SDB (AHI 3a , AHI 4 , ODI 3 , and ODI 4 ).

CONCLUSIONS

Predictors of hypertension differed by HIV status. SDB was associated with hypertension in men without HIV, but not in men with HIV. Among men with HIV, SDB did not affect the odds of hypertension.

HIV and hypertension epidemiology

PURPOSE OF REVIEW

The aim of this study was to provide an overview of the burden, pathogenesis, and recent recommendations for treating hypertension among people living with HIV (PLWH). This review is relevant because of the increase in the prevalence of HIV as a chronic disease and the intersection of the increasing prevalence of hypertension.

RECENT FINDINGS

The contribution of HIV to the pathogenesis of hypertension is complex and still incompletely understood. Evidence suggests that chronic inflammation from HIV, antiretroviral treatment (ART), and comorbidities such as renal disease and insulin resistance contribute to developing hypertension in PLWH. Treatment is not distinct from guidelines for HIV-noninfected people. Nonpharmacological guidelines such as decreasing blood pressure by promoting a healthy lifestyle emphasizing exercise, weight loss, and smoking cessation are still recommended in the literature. The pharmacological management of hypertension in PLWH is similar, but special attention must be given to specific drugs with potential interaction with ART regimens. Further research is needed to investigate the pathways and effects of hypertension on HIV.

SUMMARY

There are different pathways to the pathogenesis of hypertension in PLWH. Clinicians should take it into consideration to provide more precise management of hypertension in PLWH. Further research into the subject is still required.

Differences in hypertension and prehypertension among people living with and without HIV in China: role of HIV infection and antiretroviral therapy

OBJECTIVES

Hypertension is a growing health concern in people living with HIV (PLWH). However, association between HIV infection and hypertension is equivocal.

METHODS

In all, 1472 PLWH and 2944 HIV-negative individuals frequency-matched by age and sex were derived from the baseline survey of Comparative HIV and Aging Research in Taizhou (CHART), China. Prehypertension was defined as systolic blood pressure (BP) of 120-139 mmHg and/or diastolic blood pressure of 80-89 mmHg.

RESULTS

Despite the fact that prevalence of hypertension was overall lower among PLWH than among HIV-negative people (21.1% vs. 29.1%, P < 0.001), it was similar at ages 18-29 (7.6% vs. 8.5%) and 30-44 years (17.1% vs. 18.5%) but significantly lower in PLWH at ages 45-59 (26.1% vs. 40.7%) and 60-75 years (37.1% vs. 57.3%). Prehypertension prevalence was consistently higher in PLWH across all age groups. In the model adjusting for traditional risk factors, HIV infection was associated with hypertension (adjusted odds ratio [aOR] = 1.27, 95% confidence interval: 1.04-1.55) and prehypertension (aOR = 1.77, 95% CI: 1.51-2.08), and attenuated after additional adjustment for abdominal obesity. Age-stratified analysis showed that these associations of HIV with hypertension were observed at ages 18-29 and 30-44 years and associations with prehypertension were observed at ages 18-29, 30-44 and 45-59 years only. Years since HIV diagnosis and stavudine use were the HIV-specific factors independently associated with hypertension or/and prehypertension.

CONCLUSIONS

HIV infection is independently associated with prehypertension and hypertension especially at younger ages, and this risk may increase as treatment becomes prolonged. Our findings reinforce the urgent necessity for active BP screening and control strategies be adopted for PLWH in China.

General and abdominal obesity and incident hypertension among people living with HIV on antiretroviral therapy

Hypertension is highly prevalent among people living with HIV (PLWH). We sought to characterize the hypertension incidence among PLWH on antiretroviral therapy, focusing on the effect of change in general and abdominal obesity on hypertension during follow-up. This was a prospective analysis of 229 treated PLWH aged over 40 years without hypertension at baseline. Overall a median follow-up of 2.9 years, 26.2% PLWH developed hypertension. In multivariable models, compared to those without obesity measures at both baseline and follow-up visit, PLWH with general obesity at both occasions (adjusted odds ratio [aOR] = 3.83, P = 0.006) or at baseline only (aOR = 5.45, P = 0.003), abdominal obesity (measured as waist circumference) at both occasions (aOR = 3.87, P = 0.001) or at follow-up only (aOR = 2.27; 9P = 0.060), abdominal obesity (measured as waist-to-hip ratio) at both occasions (aOR = 2.27, P = 0.077) were at increased risk of incident hypertension. Our data show that both general and abdominal obesity especially in the persistent status increase the hypertension risk in treated PLWH.

Adipocytokine dysregulation, abnormal glucose metabolism, and lipodystrophy in HIV-infected adolescents receiving protease inhibitors

BACKGROUND

Lipodystrophy is common in HIV-infected patients receiving protease inhibitors (PIs), stavudine, and zidovudine. Adipocytokines may be altered in lipodystrophy. We evaluated risk factors, adipocytokine levels, insulin resistance, and lipid profiles in HIV-infected adolescents with different lipodystrophy types.

METHODS

A cross-sectional study was conducted in 80 perinatally HIV-infected adolescents receiving PI-based highly active antiretroviral therapy for ≥ 6 months. Patients underwent oral glucose tolerance tests and measurements of high-molecular-weight (HMW) adiponectin, leptin, resistin, insulin, and lipids. They were classified into 3 groups based on the clinical findings: no lipodystrophy, isolated lipoatrophy, and any lipohypertrophy (isolated lipohypertrophy or combined type).

RESULTS

Of the 80 patients (median age, 16.7 years), 18 (22.5%) had isolated lipoatrophy, while 8 (10%) had any lipohypertrophy (four with isolated lipohypertrophy, and four with the combined type). In a multivariate analysis, longer exposure to stavudine (OR: 1.03; 95% CI, 1.01-1.06; p = 0.005) and indinavir (OR: 1.03; 95% CI, 1.01-1.06; p = 0.012) were associated with lipoatrophy, while longer exposure to didanosine (OR: 1.04; 95% CI, 1.01-1.08; p = 0.017) and indinavir (OR: 1.10; 95% CI, 1.00-1.21; p = 0.045) were associated with any lipohypertrophy. Leptin levels were highest in the any-lipohypertrophy group and lowest in the isolated-lipoatrophy group (p = 0.013). HMW adiponectin levels were significantly lowest in the any-lipohypertrophy group and highest in the no-lipodystrophy group (p = 0.001). There were no significant differences in the levels of resistin among the three groups (p = 0.234). The prevalence of insulin resistance (p = 0.002) and prediabetes/diabetes (p < 0.001) were significantly highest in the any-lipohypertrophy group. Patients with lipoatrophy and those without lipodystrophy had comparable degrees of insulin resistance (p = 0.292). In multiple linear regression analysis, adjusted for age, sex, and waist-height ratio, HMW adiponectin levels were associated with Matsuda index (β = 0.5; p = 0.003) and quantitative insulin sensitivity check index (QUICKI) (β = 40.1; p = 0.010) and almost significantly associated with homeostatic model assessment of insulin resistance (HOMA-IR) (p = 0.054). Leptin and resistin levels were not associated with HOMA-IR, Matsuda index, or QUICKI (all p > 0.05).

CONCLUSIONS

Abnormal glucose metabolism and dysregulation of adipocytokines were common in the HIV-infected adolescents with lipohypertrophy and the combined type. Preventive screening for cardiovascular diseases caused by metabolic alterations should be routinely performed.

Metabolic syndrome, biochemical markers, and body composition in youth living with perinatal HIV infection on antiretroviral treatment

People living with HIV who are on antiretroviral treatment are at increased risk of developing premature cardiovascular disease. Children with perinatal HIV infection (PHIV) have survived through their adolescence and are entering adulthood. We determined the prevalence of metabolic syndrome, abnormal biochemical markers, and characterized body composition parameters in youth living with perinatal HIV infection. This cross-sectional study was conducted at the Research Institute for Health Sciences, Chiang Mai University, Chiang Mai, Thailand from December 2017 to February 2018. PHIV-youths between 15 <25 years of age who were receiving ART were enrolled. Data collection included ART-related history, blood pressure, and anthropometric measurements. Body composition including android, gynoid fat mass, and total body fat were measured by dual-energy X-ray absorptiometry. Fasting blood was drawn to test for lipid profile, glucose, and high sensitivity c-reactive protein (hsCRP). One hundred and twenty PHIV-youths (48% female) were enrolled. Their mean age and the median duration on ART were 20.3 (SD2.6) and 14.1 (IQR 10.4–14.9) years, respectively; 76 (63%) were on first-line non-nucleoside reverse transcriptase inhibitors-based regimens. Thirty-three (28%), 74 (62%), and 13 (11%) of PHIV-youths were underweight (BMI < 18.5 kg/m²), normal (BMI 18.5–24.9 kg/m²), and overweight (BMI ≥ 25.0 kg/m²), respectively. The prevalence of metabolic syndrome was 10.6% (95%CI 5.0–16.0). Seventy-six of 113 (67.3%) of PHIV-youths had lipid alteration; the most prevalent types being low HDL (46.9%) and increased triglycerides (27.4%). Overall 43 (35.9%) had increased hsCRP (16.7% with immediate and 19.2% with high risk for CVD). Females had significantly higher percentage of android and gynoid fat, but lower Android to gynoid ratio (AGR) compared to males. There were 77%, 31%, and 21% of PHIV-youths in the overweight, normal weight, and underweight group with AGR in tertile 3, respectively. In conclusion, we documented presence of metabolic syndrome in 10.6% of PHIV-youths on ART. Increase AGR representing abdominal obesity was detected even in youths with normal BMI or underweight.

Hypertension in people living with HIV

PURPOSE OF REVIEW

This review describes what is known concerning the burden of hypertension among people living with HIV (PLHIV), and also addresses relevant topics with respect to its risk factors and clinical management.

RECENT FINDINGS

Hypertension is highly prevalent in HIV-positive populations, and may be more common than in HIV-negative populations. Risk factors contributing to the development of hypertension in PLHIV include demographic factors, genetic predisposition, lifestyle, comorbidities such as obesity, antiretroviral therapy-related changes in body composition, and potentially also immunodeficiency, immune activation and inflammation, as well as effects from antiretroviral therapy itself. Clinical management of hypertension in PLHIV requires awareness for drug-drug interactions between antiretroviral drugs and antihypertensive drugs. Awareness, treatment, and control of hypertension in PLHIV is currently suboptimal and should be improved.

SUMMARY

The burden of hypertension among PLHIV is high and its pathophysiology most likely multifactorial. Elucidating the exact pathophysiology of hypertension in PLHIV is vital as this may provide new targets to impact and improve clinical management. In the meantime, efforts should be made to improve hypertension management as per existing clinical guidelines in order to safeguard cardiovascular health and quality of life in PLHIV.

Hypertension Is a Key Feature of the Metabolic Syndrome in Subjects Aging with HIV

With widespread and effective antiretroviral therapy, the life expectancy in the HIV population has dramatically improved over the last two decades. Consequently, as patients are aging with HIV, other age-related comorbidities, such as metabolic disturbances and cardiovascular disease (CVD), have emerged as important causes of morbidity and mortality. An overrepresentation of traditional cardiovascular risk factors (RF), toxicities associated with long exposure to antiretroviral therapy, together with residual chronic inflammation and immune activation associated with HIV infection are thought to predispose to these metabolic complications and to the excess risk of CVD observed in the HIV population. The metabolic syndrome (MS) represents a clustering of RF for CVD that includes abdominal obesity, hypertension, dyslipidemia and insulin resistance. Hypertension is a prevalent feature of the MS in HIV, in particular in the aging population, and constitutes an important RF for CVD. Physicians should screen their patients for metabolic and cardiovascular risk at the regular visits to reduce MS and the associated CVD risk among people aging with HIV, since many of RF are under-diagnosed and under-treated conditions. Interventions to reduce these RF can include lifestyle changes and pharmacological interventions such as antihypertensive and lipid-lowering therapy, and treatment of glucose metabolism disturbances. Changes in antiretroviral therapy to more metabolic neutral antiretroviral drugs may also be considered.

Mechanisms Influencing Circadian Blood Pressure Patterns Among Individuals with HIV

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.

Switching from zidovudine/lamivudine to tenofovir/emtricitabine improves fat distribution as measured by fat mass ratio

OBJECTIVES

Fat mass ratio (FMR) has been suggested as an objective indicator of abnormal body fat distribution in HIV infection. Although it could provide more comprehensive information on body fat changes than limb fat mass, FMR has scarcely been used in clinical trials examining body fat distribution in HIV-infected patients.

METHODS

A subanalysis of a controlled, randomized clinical trial in virologically suppressed HIV-1-infected men switching from zidovudine (ZDV)/lamivudine (3TC) to emtricitabine (FTC)/tenofovir (TDF) versus continuing on ZDV/3TC was carried out. FMR was assessed by dual X-ray absorptiometry (DEXA) for a period of 72 weeks. Lipoatrophy was defined as FMR ≥ 1.5. Multivariate linear regression models for the change in FMR from baseline were fitted.

RESULTS

Sixty-five men were randomized and treated (28 in the FTC/TDF arm and 37 in the ZDV/3TC arm), and 57 completed the study (25 and 32 in each arm, respectively). In the FTC/TDF arm, adjusted mean FMR decreased by 0.52 at week 72 (P = 0.014), and in the ZDV/3TC arm it increased by 0.13 (P = 0.491; P between arms = 0.023). Among subjects with lipoatrophy (baseline FMR ≥ 1.5), adjusted FMR decreased by 0.76 (P = 0.003) in the FTC/TDF arm and increased by 0.21 (P = 0.411; P between arms = 0.009) in the ZDV/3TC arm. Baseline FMR and treatment group were significant predictors (P < 0.05) of post-baseline changes in FMR.

CONCLUSIONS

Switching from ZDV/3TC to FTC/TDF led to an improvement in FMR, compared with progressive worsening of FMR in subjects receiving ZDV/3TC, showing that fat mass not only increased but was also distributed in a healthier way after the switch.

Diuretics and bioimpedance-measured fluid spaces in hypertensive patients

The authors examined the relationship between thiazide-type diuretics and fluid spaces in a cohort of hypertensive patients in a retrospective study of 60 stable hypertensive patients without renal abnormalities who underwent whole-body bioimpedance analysis. Overhydration was greater in the diuretic group, but only to a nonsignificant degree (5.9 vs. 2.9%; P=.21). The total body water did not differ in the two groups (41.8 L vs. 40.5 L; P=.64). Extracellular fluid volume (ECV) (19.7 L vs. 18.5 L; P=.35) and intracellular fluid volume (ICV) spaces (20.8 L vs. 21.3 L; P=.75) were also not significantly different in the two groups. The ratio of ICV:ECV, however, appeared different: 1.05 vs 1.15 (P=.017) and the effect was maintained in the linear regression-adjusted model (β coefficient: -0.143; P=.001). The diuretic-related distortion of ICV:ECV ratio indicates potential fluid redistribution in hypertensive patients, with ICV participating in the process.

The association of adiposity with kidney function decline among HIV-infected adults: findings from the Fat Redistribution and Metabolic Changes in HIV Infection (FRAM) study

OBJECTIVES

The aim of the study was to investigate the association of adiposity with longitudinal kidney function change in 544 HIV-infected persons in the Study of Fat Redistribution and Metabolic Change in HIV infection (FRAM) cohort over 5 years of follow-up.

METHODS

The regional distribution of muscle and adipose tissue was quantified by whole-body magnetic resonance imaging (MRI), and total adiponectin and leptin levels were measured in serum. Kidney function was assessed using the estimated glomerular filtration rate from serum cystatin C (eGFRCys), obtained at baseline and follow-up. Rapid kidney function decline was defined as annual loss of eGFRCys ≥ 3 mL/min/1.73 m(2) , and incident chronic kidney disease (CKD) was defined as eGFRCys <60 mL/min/1.73 m(2) . Multivariate regression analysis was adjusted for age, race, gender, glucose, antihypertensive use, serum albumin, baseline and change in HIV viral load.

RESULTS

At baseline, mean age was 43 years, mean eGFRCys was 86 mL/min/1.73 m(2) , and 21% of patients had albuminuria. The mean (± standard deviation) eGFRCys decline was -0.11 ± 4.87 mL/min/1.73 m(2) per year; 23% of participants had rapid kidney function decline, and 10% developed incident CKD. The lowest tertile of visceral adipose tissue and the highest tertile of adiponectin were both marginally associated with annual kidney function decline of -0.5 mL/min/1.73 m(2) each, but these associations were not statistically significant after adjustment. We found no statistically significant associations of MRI-measured regional adiposity or serum adipokines with rapid kidney function decline or incident CKD (all P-values>0.1 in adjusted models).

CONCLUSIONS

Contrary to findings in the general population, adiposity did not have a substantial association with longitudinal change in kidney function among HIV-infected persons.