IntroductionBreathlessness is common in the general population and associated with poorer health. Prevalence, frequencies and overlap of underlying contributing conditions among individuals reporting breathlessness in the general population is unclear. The aim was to evaluate which conditions that were prevalent, overlapping and associated with breathlessness in a middle-aged general population.MethodCross-sectional analysis of individuals aged 50–65 years in the Swedish CArdioPulmonary bioImage Study pilot. Data from questionnaire, spirometry testing and fitness testing were used to identify underlying contributing conditions among participants reporting breathlessness (a modified Medical Research Scale (mMRC) score ≥1). Multivariate logistic regression was used to identify independent associations with breathlessness.Results1097 participants were included; mean age 57.5 years, 50% women and 9.8% (n=108) reported breathlessness (mMRC ≥1). Main underlying contributing conditions were respiratory disease (57%), anxiety or depression (52%), obesity (43%) and heart disease or chest pain (35%). At least one contributing condition was found in 99.6% of all participants reporting breathlessness, while two or more conditions were present in 66%.ConclusionIn a middle-aged general population, the main underlying contributing conditions to breathlessness were respiratory disease, anxiety or depression, obesity and heart disease or chest pain with a high level of overlap.