Pneumonia in childhood and impaired lung function in adults: a longitudinal study

Abstract

Background: Diminished lung function and increased prevalence of asthma have been reported in children with a history of early lower respiratory illnesses (LRIs), including pneumonia. Whether these associations persist up to adulthood has not been established.

Methods: As part of the prospective Tucson Children's Respiratory Study, LRIs during the first 3 years of life were ascertained by pediatricians. Spirometry was performed at ages 11, 16, 22, and 26 years. The occurrence of asthma/wheeze during the previous year was ascertained at ages 11, 13, 16, 18, 22, 24, 26, and 29 years. Longitudinal random effects models and generalized estimating equations were used to assess the relation of LRIs to lung function and asthma.

Results: Compared with participants without early-life LRIs, those with pneumonia had the most severe subsequent lung function impairment, with mean ± SE deficits of -3.9% ± 0.9% (P < .001) and -2.5% ± 0.8% (P = .001) for pre- and post-bronchodilator FEV1:FVC ratio from age 11 to 26 years, respectively. Pneumonia was associated with increased risk for asthma (odds ratio [OR]: 1.95; 95% confidence interval [CI]: 1.11-3.44) and wheeze (OR: 1.94; 95% CI: 1.28-2.95) over the same age range. Early non-pneumonia LRIs were associated with mildly impaired pre-bronchodilator FEV1 (-62.8 ± 27.9 mL, P = .024) and FEV1:FVC ratio (-1.1 ± 0.5%, P = .018), and wheeze (OR: 1.37; 95% CI: 1.09-1.72).

Conclusions: Early pneumonia is associated with asthma and impaired airway function, which is partially reversible with bronchodilators and persists into adulthood. Early pneumonia may be a major risk factor for adult chronic obstructive pulmonary disease.

Keywords: asthma; early childhood pneumonia; lung function.

FIGURE 1

Numbers of subjects enrolled, with complete follow-up for LRIs in the first 3 years of life, and for whom data were available for pulmonary function tests performed at least once at ages 11, 16, 22, or 26 years.

FIGURE 2

Predicted mean values for FEV₁:FVC ratio in non-Hispanic white males at ages 11, 16, 22, and 26 years by LRIs. Closed symbols (plotted) represent the predicted mean values for lung function for non-Hispanic white male participants based on longitudinal random-effects models using base models adjusted for age, gender, height, race/ethnicity, and LRIs. All predicted mean values for lung function were standardized to mean heights for male participants at ages 11, 16, 22, and 26 years (ie, 144.5, 176.5, 178.2, and 179.0 cm, respectively). Open symbols (adjacent to the plotted symbols) represent the predicted mean values for lung function for non-Hispanic white male participants based on cross-sectional linear regression models (adjusted for gender, height, and race/ethnicity) at ages 11, 16, 22, and 26 years.

FIGURE 3

Predicted mean values for FEF_25–75 in non-Hispanic white males at ages 11, 16, 22, and 26 years by LRIs. Closed symbols (plotted) represent the predicted mean values for lung function for non-Hispanic white male participants based on longitudinal random-effects models using base models adjusted for age, gender, height, race/ethnicity, and LRIs. All predicted mean values for lung function were standardized to mean heights for male participants at ages 11, 16, 22, and 26 years (ie, 144.5, 176.5, 178.2, and 179.0 cm, respectively). Open symbols (adjacent to the plotted symbols) represent the predicted mean values for lung function for non-Hispanic white male participants based on cross-sectional linear regression models (adjusted for gender, height, and race/ethnicity) at ages 11, 16, 22, and 26 years.