No abstract

Background With the introduction of effective antiretroviral therapy (ART), people living with HIV (PLWH) are surviving longer and are at risk for developing metabolic abnormalities that contribute to cardiovascular disease (CVD). In Sub-Saharan Africa (SSA), there is a paucity of epidemiological data on lipid profiles among young adults receiving ART. This study aimed to estimate the prevalence of low high-density lipoprotein cholesterol (HDL-c), a cardioprotective lipid class, and whether it differed by age among adults on ART in Livingstone, Zambia. Methods From April to December 2019, we conducted a cross-sectional study of 597 PLWH [n = 58 aged 18–24 years (young adults); n = 539 aged ≥25 years (adults)] on ART for ≥6 months. Data collected included demographic and lifestyle information, anthropometrics, viral load (VL), CD4 count, blood pressure, lipid profiles and fasting/random blood glucose. Clinical measures were defined as: low HDL-c [<1.0 mmol/L for men, <1.3 for women], increased waist circumference (WC) [≥94 cm for men, ≥80 cm for women], high triglycerides (TG) [≥1.7 mmol/l], and virological failure (VF) [VL ≥1000 copies/μl]. We used logistic regression to examine the association between age and low HDL-c after adjusting for multiple variables. Results Among the young adults, 60% (35/58) were women, median (25th, 75th percentile) age 21 years (18, 23), and median time on ART 116 months (60, 144). Among adults, 63% (342/539) were women, median age 46 years (40, 53) and median time on ART 108 months (60, 144). Young adults had a lower CD4 count compared to adults (median, 492 vs. 568 cells/μL, p = 0.010) and higher prevalence of VF (29% vs. 17%, p = 0.016). In young adults, prevalence of low HDL-c was significantly higher than in adults (63 vs. 38%, p<0.001). A high proportion of young adults (75%) and adults (58%) with low HDL-c were on dolutegravir (DTG)-based ART regimens. After adjusting for sex, duration on ART, WC, body mass index, ART regimen, VF, CD4 count, low density lipoprotein cholesterol, blood pressure and smoking, young adults were significantly more likely than adults to have low HDL-c (odds ratio 2.93; 95% confidence interval 1.46–5.86). Conclusion Low HDL-c is highly prevalent among young adult with HIV in SSA independent of other risk factors for metabolic derangements. Lipid abnormalities among young PLWH may contribute to the early development of cardiovascular diseases in this population. This highlights the need to consider low HDL-c in the quest to reduce CVD risk among young adults on ART in SSA.

Background COVID-19 vaccines are highly effective for reducing severe disease and mortality. However, vaccine effectiveness data is limited from sub-Saharan Africa. We report COVID-19 vaccine effectiveness against progression to in-hospital mortality in Zambia. Methods We conducted a retrospective cohort study among admitted patients at eight COVID-19 treatment centers across Zambia during April 2021 through March 2022, when delta and omicron variants were circulating. Patient demographic and clinical information including vaccination status and hospitalization outcome (discharged or died) were collected. Multivariable logistic regression was used to assess the odds of in-hospital mortality by vaccination status, adjusted for age, sex, number of comorbid conditions, disease severity, and COVID-19 treatment center. Vaccine effectiveness of ≥1 vaccine dose was calculated from the adjusted odds ratio. Results Among 1,653 patients with data on their vaccination status and hospitalization outcome, 365 (22.1%) died. Overall, 236 (14.3%) patients had received ≥1 vaccine dose before hospital admission. For patients who had received ≥1 vaccine dose, 22 (9.3%) died compared with 343 (24.2%) among unvaccinated patients (p &lt;0.01). The median time since receipt of a first vaccine dose was 52.5 days (IQR: 28-107). Vaccine effectiveness for progression to in-hospital mortality among hospitalized patients was 64.8% (95% CI: 42.3-79.4%). Conclusions Among patients admitted to COVID-19 treatment centers in Zambia, COVID-19 vaccination was associated with lower progression to in-hospital mortality. These data are consistent with evidence from other countries demonstrating benefit of COVID-19 vaccination against severe complications. Vaccination is a critical tool for reducing the consequences of COVID-19 in Zambia.

The human gut microbiota environment is constantly changing and some specific changes influence the host’s metabolic, immune, and neuroendocrine functions. Emerging evidence of the gut microbiota’s role in the development of cardiovascular disease (CVD) including hypertension is remarkable. There is evidence showing that alterations in the gut microbiota and especially the gut-dependant metabolite trimethylamine N-oxide is associated with hypertension. However, there is a scarcity of literature addressing the role of trimethylamine N-oxide in hypertension pathogenesis. In this review, we discuss the impact of the gut microbiota and gut microbiota dependant trimethylamine N-oxide in the pathogenesis of hypertension. We present evidence from both human and animal studies and further discuss new insights relating to potential therapies for managing hypertension by altering the gut microbiota.