Reduced frequency of wheezing respiratory illness in infants with perinatal human immunodeficiency virus-type 1 infection: a model for immunologic and inflammatory mechanisms of airway obstruction?

A multivariate analysis using a logistic regression model evaluated odds ratio (OR) and 95% confidence limits (95% CL) of pediatrician-diagnosed wheezing respiratory illness in 75 infants with perinatal human immunodeficiency virus-type 1 (HIV-1) infection, 205 uninfected infants of HIV-1 infected mothers, and 1780 infants of HIV-1 uninfected mothers. Infants were prospectively followed-up for the first 2 years of life. Covariates were risk factors for wheezing respiratory illness (preterm delivery, low birth weight, maternal smoking, formula feeding, and neonatal respiratory disorders). Maternal use of illicit drugs in pregnancy, antiretroviral treatment in pregnancy, maternal HIV-1-related clinical condition at the time of delivery were also included in the models when infants of HIV-1 infected mothers were taken into account. Although the frequency of risk factors for wheezing respiratory illness was higher in infants of HIV-1 infected than in those of uninfected mothers, HIV-1 infection emerged as a protective factor [OR: 0.001 (95% CL: 0.0001-0.01); p < 0.001]. The frequency of risk factors was similarly high among infants of infected mothers, but OR was lower in HIV-1 infected than in uninfected infants of infected mothers (0.005; 95% CL: 0.0004-0.06; p < 0.001). Finally, OR was higher in uninfected infants of HIV-1 infected mothers (who evidenced a higher frequency of risk factors) than in infants of HIV-1 uninfected mothers (9.97; 95% CL: 4.87-20.40; p < 0.001). Understanding the reason why HIV-1 protects against wheezing respiratory illness could shed light on the immunologic and inflammatory mechanisms of airway obstruction.