There is evidence for endothelial dysfunction in youth living with perinatally acquired HIV (YLPHIV). However, little data exist on its mechanisms. YLPHIV and age-matched HIV-uninfected (HIV-) youth enrolled in the Cape Town Adolescent Antiretroviral Cohort in South Africa between 9 and 14 years of age were included. YLPHIV were on antiretroviral therapy more than 6 months with viral load less than 400 copies/ml at baseline and 24 months. Serum biomarkers of systemic inflammation, monocyte activation, intestinal integrity, and oxidized LDL-cholesterol were measured at baseline and after 24 months. Endothelial function was measured at 24 months using reactive hyperemic index (RHI); endothelial dysfunction was defined as RHI less than 1.35. Spearman correlation coefficient and quantile regression were used to examine associations between RHI and different biomarkers. We included 266 YLPHIV and 69 HIV- participants. At baseline, median (Q1, Q3) age was 12 (11, 13) years and 53% were females. YLPHIV had poorer endothelial function compared with HIV- youth (RHI = 1.36 vs. 1.52, P < 0.01). At baseline and 24 months, YLPHIV had higher markers of monocyte activation (soluble CD14), gut barrier dysfunction (intestinal fatty acid binding protein) and oxidized LDL-cholesterol (P ≤ 0.04) compared with HIV- youth. Among YLPHIV, soluble CD14 remained associated with endothelial dysfunction after adjusting for age, sex, Tanner stage, and antiretroviral therapy duration (β: -0.05, P = 0.01). Despite viral suppression, South African YLPHIV have poor endothelial function and persistent evidence of monocyte activation and gut barrier dysfunction compared with HIV- youth. The long-term clinical significance of gut integrity and monocyte activation needs to be further assessed in YLPHIV.
Because of antiretroviral therapy (ART), people are living with HIV infection longer than ever before. As this patient group ages, it is expected that medical comorbidities such as osteoporosis and fragility fractures will increase. The purpose of this review is to address the epidemiology and what is known regarding the pathogenesis of bone loss in people living with HIV infection with a focus on recently published literature.HIV-infected individuals are at increased risk for low bone mineral density and bone fractures. The cause of bone loss in HIV is multifactorial including traditional risk factors some of which disproportionately affect HIV-infected individuals and alterations in bone metabolism due to ART, HIV viral proteins and chronic inflammation. Lifestyle modification, changing ART, calcium and vitamin D supplementation and pharmacologic treatment for osteoporosis may all be employed to abrogate bone loss in this patient group.Clinicians should be aware of the contributors to bone loss in people living with HIV in order to recognize high-risk individuals and to take appropriate steps to address modifiable risk factors to prevent future fracture.
Background: HIV-infected patients who fail to normalize CD4 T cells despite suppressive antiretroviral therapy have impaired immune homeostasis: diminished naive T-cell numbers, elevated T-cell turnover, senescence, and inflammation. Methods: Blood samples from immune failures (n = 60), immune successes (n = 20), and healthy controls (n = 20) were examined for plasma interleukin (IL)-7 levels, for cellular expression of the IL-7Rα chain (CD127), for the exhaustion and senescence markers programed death 1 (PD-1) and CD57, and for the survival factor Bcl2. Because both inflammatory and homeostatic cytokines can induce T-cell cycling, we also examined the effects of these mediators on exhaustion and senescence markers. Results: Plasma levels of IL-7 were elevated and both CD4 and CD8 T-cell CD127 expression was decreased in immune failure. Plasma levels of IL-7 correlated directly with naive CD4 T-cell counts in immune success and inversely with T-cell cycling (Ki67) in healthy controls and immune success, but not in immune failure. CD4 T-cell density of PD-1 was increased and Bcl2+ CD4 T cells were decreased in immune failure but not in immune success, whereas the proportion of T cells expressing CD57 was increased in immune failure. PD-1 and CD57 were induced on CD4 but not CD8 T cells by stimulation in vitro with inflammatory IL-1β or homeostatic (IL-7) cytokines. Conclusions: Perturbation of the IL-7/IL-7 receptor axis, increased T-cell turnover, and increased senescence may reflect dysregulated responses to both homeostatic and inflammatory cytokines in immune failure patients.
Objectives To compare the prevalence of detectable coronary artery calcium (CAC) among higher risk, older people living with HIV (PLWH) and uninfected persons in Uganda versus the USA, and second to explore associations of CAC with HIV-specific variables and biomarkers of inflammation. Methods This cross-sectional study of 430 total subjects compared 100 PLWH on antiretroviral therapy and 100 age-matched and sex-matched HIV-uninfected controls in Uganda with 167 PLWH on antiretroviral therapy and 63 uninfected controls in the USA. Multivariable logistic regression was used to examine associations with detectable CAC (CAC >0). Results Compared with US subjects, Ugandans were older (mean age 56 vs 52 years) and were more likely to have diabetes (36% vs 3%) and hypertension (85% vs 36%), but were less likely to be male (38% vs 74%) or smokers (4% vs 56%). After adjustment for HIV serostatus, age, sex and traditional risk factors, Ugandans had substantially lower odds of CAC >0 (adjusted OR 0.07 (95% CI 0.03 to 0.17), p<0.001). HIV was not associated with CAC >0 in either country (p>0.1). Among all PLWH, nadir CD4 count was associated with the presence of CAC, and among Ugandans soluble intercellular adhesion molecule (p=0.044), soluble CD163 (p=0.004) and oxidised low-density lipoprotein (p=0.043) were all associated with the presence of CAC. Conclusions Ugandans had a dramatically lower prevalence of any coronary calcification compared with US subjects. The role of HIV infection and inflammation as risk factors for subclinical coronary disease in sub-Saharan Africa merits further investigation.
Background Vitamin D deficiency is common in HIV-infected individuals. In adults, traditional and HIV-related factors play a role in vitamin D status, and deficiency appears to impair immune restoration and exacerbate HIV complications, like cardiovascular disease (CVD). This study sought to determine factors contributing to vitamin D status in HIV-infected youth and investigate the relationship with CVD risk, inflammation and immune restoration. Methods HIV-infected subjects (1-25 years old) were enrolled prospectively along with healthy controls that were group-matched by age, sex and race. HIV data were collected for the HIV-infected group, while traditional risk factors, including vitamin D intake, sun exposure, skin pigmentation, physical activity level and body mass index (BMI) were collected for both groups. Fasting lipids, plasma 25-hydroxyvitamin D (25[OH]D), and inflammation markers were measured. Results In total, 200 HIV-infected subjects and 50 controls were enrolled. HIV group had 53% male, 95% Black and a mean age of 17.2 ±4.6 years. There was no difference in 25(OH)D between groups; 77% of HIV+ and 74% of controls had 25(OH)D<20 ng/ml. Only Fitzpatrick skin type was independently associated with 25(OH)D. No HIV variables were associated with 25(OH)D, even when HIV sub-populations were examined. Inflammation, CVD risk factors and immune restoration were not independently associated with 25(OH)D. Conclusions Vitamin D deficiency is common among HIV-infected youth. However, HIV factors, CVD risk, inflammation and immune restoration do not appear to have the same relationship with vitamin D as has been shown in adults. Supplementation trials are needed to determine if increasing 25(OH)D concentrations could better elucidate these relationships.
Background/Purpose: Avascular necrosis (AVN) can result in significant morbidity. Previous studies suggest that AVN is associated with systemic lupus erythematosus (SLE) and corticosteroid treatment. Hypovitaminosis D has been postulated to play a role in bisphosphonate‐associated osteonecrosis of the jaw. Using frozen serum and demographic data from the Atherosclerosis Prevention in Pediatric Lupus Erythematosus (APPLE) trial, we conducted an exploratory analysis to assess associations between AVN and demographics, SLE disease activity and vitamin D deficiency, defined as serum 25‐hydroxyvitamin D [25(OH)D] <20 ng/mL. Methods: APPLE trial participants were randomized to placebo or atorvastatin. Frozen serum collected at baseline was used to measure 25(OH)D levels by chemiluminescent assay (IDS, LTD). Univariable analysis of APPLE data at baseline to 3 years was performed using chi‐squared test for categorical baseline variables and Wilcoxon signed rank test for continuous variables. Results: Samples were available for 201/221 APPLE participants. 17/201 (8.4%) either had a history of (n = 9) or developed AVN during the study period (n = 8). Vitamin D deficiency, minority status, southern latitude, elevated triglycerides, and a history of hypertension and/or glomerulonephritis were associated with the presence or development of AVN ( ). Body mass index, presence of antiphospholipid antibodies, SLEDAI, SLE disease duration and corticosteroid use were not associated with AVN. Conclusion: This is the first report of vitamin D deficiency associated with AVN in pediatric lupus. There was a trend towards lower vitamin D levels in subjects who developed AVN during the 3 years of the trial, but this was not statistically significant likely due to low numbers. AVN has devastating consequences, and its pathogenesis is likely multi‐factorial. Unlike other studies, no association was seen between steroid use and AVN. This association does not prove causation, but suggests future avenues of study and may suggest a method of prevention for AVN. Univariable analysis on APPLE data at baseline to 3 years Variable No AVN AVN P‐value No(%) Median (25 th , 75 th ) Baseline 25(OH)D (ng/mL) 25.9 (18.9, 31.6) 18.7 (15.1, 32.2) NS 25 (OH)D<20 ng/mL 52/184 (28.3%) 9/17 (52.9%) 0.034 White/Caucasian non Hispanic 113/184 (61.4%) 15/17 (88.2%) 0.028 Age (years) 15.5 (13.7, 17.6) 16.5 (14.5, 18.0) NS Female 153/184 (83.2%) 14/17 (82.4%) NS SLE duration (months) 23.5 (8.0, 44.5) 25.0 (7.0, 45.0) NS SLEDAI 4.0 (2.0, 6.0) 4.0 (0.0, 8.0) NS History of hypertension 55/178 (30.9%) 10/17 (58.8%) 0.020 History of glomerulonephritis 58/183 (31.7U%) 12/17 (70.6%) 0.001 History of nephritis/nephrosis 67/183 (36.6%) 14/17 (82.4%) <0.001 Corticosteroid use 148/183 (80.9%) 15/17 (88.2%) NS Triglycerides (mg/dL) 99.5 (74, 130.0) 145.5 (88.5, 161.0) 0.050 Total cholesterol (mg/dL) 146.0 (124.0, 173.0) 160.5 (145.5, 183.0) NS C3 (mg/dL) 99.0 (85.0, 122.0) 108.5 (99.5, 115.0) NS C4 (mg/dL) 13.7 (9.0, 19.) 19.3 (15.1, 22.9) 0.017 Latitude (°N) 40.7 (37.4, 40.9) 37.4 (36.0, 40.0) 0.004
Previous studies demonstrated associations between reduced serum 25-hydroxyvitamin D (25OHD), inflammation and disease activity in paediatric systemic lupus erythematosus (pSLE). The goal of this study was to assess parathyroid hormone (PTH) in its relationship to vitamin D and inflammation, as well as to better understand the role of human cathelicidin (LL-37) in pSLE.Frozen serum samples collected at baseline of the Atherosclerosis Prevention in Paediatric Lupus Erythematosus (APPLE) study were assayed to determine 25OHD, PTH and LL-37 levels. Pearson's correlations and Χ2 tests were used to evaluate the relationships between 25OHD, PTH, LL-37, inflammation, disease activity and infection using baseline values collected as part of the APPLE study.201/221 APPLE participants had serum available for analysis. Serum 25OHD was inversely associated with serum PTH, but not LL-37. Serum PTH was not associated with high sensitivity C-reactive protein, carotid intima media thickness or high-density lipoprotein (HDL) or low-density lipoprotein (LDL) cholesterol, but was negatively associated with lipoprotein(a) levels. Despite no association with serum 25OHD, LL-37 was negatively associated with total cholesterol, HDL and LDL cholesterol and positively associated with age. There was no significant difference in mean LL-37 levels in participants with reported infection as an adverse event during the 3-year APPLE study.Despite links to vitamin D levels in other studies, LL-37 levels were not associated with baseline serum 25OHD concentrations in paediatric patients with pSLE. Despite the lack of correlation with 25OHD, LL-37 levels in this study were associated with cholesterol levels. Some subjects with pSLE have significantly elevated levels of LL-37 of unknown significance. These exploratory results addressing the role of LL-37 levels in pSLE appear worthy of future study.
We compared bone mineral density (BMD) changes and their correlates, between men and women participating in two randomized trials of initial [antiretroviral therapy (ART)] regimens, with or without tenofovir disoproxil fumarate (TDF).
