Comparing children's night cough with wheeze: phenotypic characteristics, healthcare use and treatment

Population-based studies of children presenting with dry night cough alone compared with those who also wheeze are few and inconclusive. Luftibus in the school is a population-based study of schoolchildren conducted between 2013-2016 in Zurich, Switzerland. We divided children into four mutually exclusive groups based on reported dry night cough ( cough) and wheeze and compared parent-reported symptoms, comorbidities and exposures using multinomial regression, FeNO using quantile regression, spirometry using linear regression and healthcare use and treatments using descriptive statistics. Among 3457 schoolchildren aged 6-17 years, 294 (9%) reported cough, 181 (5%) reported wheeze, 100 (3%) reported wheeze and cough and 2882 (83%) were asymptomatic. Adjusting for confounders in a multinomial regression, children with cough reported more frequent colds, rhinitis and snoring than asymptomatic children; children with wheeze or wheeze and cough more often reported hay fever, eczema and parental histories of asthma. FeNO and spirometry were similar among asymptomatic and children with cough, while children with wheeze or wheeze and cough had higher FeNO and evidence of bronchial obstruction. Children with cough used healthcare less often than those with wheeze, and they attended mainly primary care. Twenty-two children (7% of those with cough) reported a physician diagnosis of asthma and used inhalers. These had similar characteristics as children with wheeze. Our representative population-based study suggests only a small subgroup (7%) of schoolchildren reporting dry night cough without wheeze have features typical of asthma, yet the majority (93%) should be investigated for alternative aetiologies, particularly upper airway disease. Take home messageOur population-based study found children with night cough alone clearly differ from those with wheeze, suggesting different aetiologies and pathophysiology. Yet, a small subgroup (7%) has features of asthma and may benefit from specific work-up.