The number of long-term survivors of human immunodeficiency virus (HIV)-1 who develop asthma-like features is increasing, but the causes of airway hyperresponsiveness (AHR) and airway inflammation are unknown. Thus, researchers investigated these symptoms in Japanese patients with stable HIV infections, and found a high prevalence of the neutrophilic inflammatory phenotype.

According to the study’s lead author, Chiyo Yano, the team’s findings “provide insight into the mechanisms of AHR and may facilitate the development of novel treatment for individuals with AHR and HIV infection.” Their report was published in the Journal of Infection and Chemotherapy.

The study ultimately included 84 patients, among which 34 were HIV-positive and 50 were HIV-negative. Researchers classified eosinophilic, neutrophilic, mixed (eosinophilic and neutrophilic), and paucigranulocytic airway inflammatory phenotypes based on sputum characteristics.

The authors reported that 32.4% of patients with HIV had AHR, which was a significantly higher prevalence than the 10.0% in non-HIV-infected patients (P = 0.0213). The analysis further demonstrated that HIV was an independent risk factor for AHR. Additionally, patients with HIV were significantly more likely to have a neutrophilic airway inflammatory phenotype than patients with HIV (P = 0.0358). The researchers observed a significant association between AHR levels and the percentage of sputum neutrophils (r = –0.65; P = 0.0316). Sputum neutrophil percentage was also negatively correlated with the blood CD4 cell count (r = –0.66; P = 0.0266).

The authors summarized that “neutrophilic airway inflammation and a decline in the blood CD4 cell count” may be contributors in the development of AHR. They speculated that improving HIV treatments to increase CD4 cell counts may prevent AHR from developing in long-term survivors with HIV-infection.

Source: Journal of Infection and Chemotherapy