Prevalence, incidence, and characteristics of chronic cough among adults from the canadian longitudinal study on ageing (CLSA)

Abstract

<b>Background:</b> The global prevalence of chronic cough(CC) is highly variable ranging from 2-18%. <b>Objectives:</b> Assess the prevalence and incidence of CC in Canada and how are these influenced by age, sex, smoking, respiratory symptoms, medical co-morbidities, and lung function. <b>Methods:</b> Participants with CC were identified from the Canadian Longitudinal Study on Ageing (CLSA) based on a self-reported daily cough in the last 12 months. This is a prospective, nationally generalizable, stratified random sample, aged 45-85 at baseline from the 10 Canadian provinces recruited between 2011-2015, and followed-up 3 years later. This study uses data from 30097 of 51338 participants on whom comprehensive assessments were completed at each visit. The prevalence and incidence per 100-person-years are described, with adjustments for age, sex and smoking status. <b>Results:</b>29972 completed the CC question at baseline and 26701 at follow-up. The prevalence of CC was 15.8% at baseline and 17.6% at follow-up with variation across provinces. Prevalence increased with age, current smoking, and was higher in males(15%), Caucasians(14%), and those born in North America, Europe or Oceania(14%). The incidence of chronic cough adjusted for age, sex and smoking was higher in males, underweight and obese. Those with wheeze, airflow obstruction, lower FEV1%pred, COPD,asthma, past pneumonia or influenza, cardio-vascular diseases, psychological disorders, diabetes and chronic pain had a higher incidence of chronic cough. <b>Conclusion:</b> The prevalence and incidence of CC is high in the CLSA with geographic, ethnic and gender differences. Multiple medical co-morbidities increased the incidence of CC.