Heritability of cough across two generations: the RHINESSA study

Heritability of cough has not yet been studied. We aimed to evaluate if individuals with cough are more likely to have offspring who develop cough, and if these associations differ by type of cough (productive/non-productive).The RHINESSA Generation Study (Respiratory Health In Northern Europe, Spain and Australia) includes 7155 parents (initially aged 30–54) answering detailed questionnaires in 2000 and 2 010, and 8176 offspring ≥20 years answering similar questionnaires in 2012–2019. Chronic cough was categorized as productive or non-productive (dry) cough. Associations between parental and offspring cough were analyzed using mixed-effects logistic regression, adjusting for offspring age, sex, body mass index, smoking history, education level, current asthma, rhinitis, nocturnal gastroesophageal reflux; parent sex and smoking history; center and family.Among parents with non-productive cough, 11% of their offspring reported non-productive cough, compared with 7% of offspring to parents without non-productive cough, adjusted odds ratio (aOR) 1.59 (95% confidence interval 1.20–2.10). Among parents with productive cough, 14% of their offspring reported productive cough, compared with 11% of offspring to parents without productive cough, aOR 1.34 (1.07–1.67). No associations were found between parent productive cough – offspring non-productive cough, nor between parent non-productive cough – offspring productive cough.Parents with chronic cough are more likely to have offspring with chronic cough independent of parental asthma, suggesting cough to be a separate heritable trait. The type of cough is important, as the non-productive cough in parent associates only with non-productive cough in offspring, and the same applied for productive cough.