Rationale: Oxidative stress may increase the risk of asthma, contribute to asthma progression, and decrease lung function. Previous research suggests that use of acetaminophen, which is hypothesized to reduce antioxidant capacity in the lung, is associated with an increased risk of asthma. We hypothesized that acetaminophen use may also be associated with chronic obstructive pulmonary disease (COPD) and decreased lung function.
Objectives: To investigate the associations between use of pain medication, particularly acetaminophen, and asthma, COPD, and FEV1 in adults.
Methods: A cross-sectional analysis using the Third National Health and Nutrition Examination Survey.
Measurement and main results: Increased use of acetaminophen had a positive, dose-dependent association with COPD (adjusted odds ratio for increasing category of intake, 1.16; 95% confidence interval [CI], 1.09-1.24; p value for trend < 0.001) and an inverse association with lung function (daily user compared with never users, -54.0 ml; 95% CI, -90.3 to -17.7, adjusted). Neither of these associations was explained by overlap between COPD and asthma occurrence. We confirmed a dose-response association of acetaminophen use and asthma (adjusted odds ratio, 1.20; 95% CI, 1.12-1.28; p value for trend < 0.001).
Conclusions: This study provides further evidence that use of acetaminophen is associated with an increased risk of asthma and COPD, and with decreased lung function.