Abstract
Rationale: Household air pollution (HAP) and human immunodeficiency virus (HIV) are associated with increased risk for chronic obstructive pulmonary disease. Both HAP and HIV are widespread in Sub-Saharan Africa, including Malawi, where HIV has 10.6% prevalence in patients 15–49 years old. Objectives: We hypothesized that HIV infection (HIV(+)) and habitual exposure to HAP (HAP(+)) synergize to cause systemic inflammation and vascular injury, which may herald early onset of chronic respiratory diseases. Methods: In this pilot study, 50 subjects from Malawi with known HIV status were administered surveys recording demographics, HAP exposure, and respiratory symptoms/diagnoses. Peripheral blood was collected, and Meso Scale Discovery V-Plex assay was used to measure the levels of 41 serum markers. Results: Almost all subjects (96%) reported HAP(+), 30 were HIV(+), 20 were HIV(−), with a mean age of 22 years in both groups. More females (73%) were HIV(+), whereas 65% of those who were HIV(−) were males. The vast majority were never-smokers (70% of HIV(−) and 83% of HIV(+) subjects, respectively). Forty-six percent of all subjects (57% of HIV(+)HAP(+) and 33% of HIV(−)HAP(+)) reported respiratory diagnoses and/or respiratory symptoms, with breathlessness and cough being most common. Although HIV(+)HAP(+) individuals had a trend to increased proinflammatory cytokines and vascular injury markers, and decreases in proangiogenic factors compared with HIV(−)HAP(+), only the decrease in serum interleukin-16 (by 44%) was statistically significant (P = 0.03). Also, compared with other subjects, serum interleukin-2 levels were significantly decreased (by 31%; P = 0.02) in HIV(+) subjects with persistent respiratory symptoms. Conclusions: This study suggests a high prevalence of respiratory symptoms in HIV(+) individuals exposed to HAP. The significant decrease in interleukin-2 and interleukin-16, cytokines associated with HIV clearance, may contribute to viral persistence, and because their low levels were found to correlate with chronic obstructive pulmonary disease severity, they may serve as biomarkers for risk of chronic obstructive pulmonary disease in this vulnerable population.