The Influence of Constipation on Asthma: A Real-world, Population-based
Background Among respiratory diseases, asthma is one of the most
burdensome disorder worldwide. Growing evidence disclose gut dysbiosis
may contribute to asthma via the gut-lung axis. Constipation can lead to
alteration of the gut microflora. The clinical impact of constipation on
asthma has not been researched. Therefore, we aim to assess the risk of
asthma in constipated patients by a nationwide population-based cohort
study. Methods We analyzed 82421 constipated patients and 82421
individuals without constipation between 1999 and 2013 from the
Taiwanese National Health Insurance Research Database. Analysis of
propensity score was utilized to match age, gender, comorbidities, and
medications at a ratio of 1:1. Besides, multiple Cox regression analysis
was performed to evaluate the adjusted hazard ratio of asthma.
Furthermore, sensitivity tests and a stratified analysis were conducted.
Results The incidence of asthma was 10.8 per 1,000 person-years in the
constipation group, which was higher than the rate of 5.6 per 1,000
person-years observed in the non-constipation group. After adjustment
for age, gender, comorbidities, and medications, constipated patients
had a 1.91-fold greater risk of asthma compared to those without
constipation (adjusted hazard ratio [aHR]: 1.91 (95% C.I.
1.84-1.99). In subgroup analyses, patients aged 20-39 years had a
2.04-fold highest risk of asthma in the constipation cohort (aHR:2.04,
95% CI, 1.84-2.26). Besides, the severity of constipation is associated
with an increased risk of asthma; the aHR was 1.76 (1.69-1.85),
2.15(2.03-2.27), and 2.29(2.10-2.49) for < 3 times, 3-12
times, and ≥12 times of laxatives prescription within one year,
respectively. (p<0.001) Moreover, constipated patients had a
higher likelihood of asthma, regardless of gender, comorbidities, and
medications. Conclusion Constipation relates to a significantly
increased risk of asthma. Physicians should be aware of the possibility
of asthma in constipated people. Further research is warranted to
investigate the possible pathological mechanisms of this association.