Interactive effects of family history of respiratory disease with age and body mass index on the risk of chronic bronchitis: A Cross-sectional Study

Abstract

Family history of respiratory disease (FHRD) is linked to chronic bronchitis (CB).This study aimed to investigate whether FHRD interacted with age and body mass index (BMI) to increase the risk of CB. A cross-sectional analysis was conducted on 22533 participants enrolled from the Beijing Population Health Cohort Study. Age and BMI were transformed into binary variables using cut-off points of 65 years old and 24 kg/m², correspondingly. Logistic regression was used to examine the independent and interactive effects among FHRD, age and BMI on CB. Additive interactions between FHRD and age or BMI were further estimated using relative excess risk due to interaction (RERI), attribute proportion due to interaction (AP), and synergy index (S). FHRD was positively associated with the risk of CB (OR 2.21, 95% CI 1.92–2.55 ), which was enhanced by age ≥ 65 years old to 3.43 (95% CI 2.53–4.65) and by BMI ≥ 24 kg/ m² to 2.99 (95% CI 2.40–3.72). There was no significant additive interaction between FHRD and age or BMI on CB. FHRD, older age and higher BMI were independently associated with increased risk of CB. Nevertheless, no interactive effects between FHRD and age or BMI were observed, and further studies were needed.