The Epidemiology of Respiratory Impairment and Disease in Two Generations of the Renfrew and Paisley (midspan) Study

Measures of respiratory symptoms and function have been studied in two successive generations over a 25 year period, based on a larger original cohort of 15,411 men and women aged 45-64 and a subsequent family study comprising 2298 adult sons and daughters aged 30-59 from 1477 families. Poor respiratory health is a dominant feature of the original cohort, in association with high rates of socio-economic deprivation and mortality rates from all causes. Measures of chronic obstructive pulmonary disease (COPD), such as the MRC chronic bronchitis questionnaire, hospital admissions and death certification, underestimate the contribution of measured respiratory impairment to poor health and premature mortality. Cigarette smoking within families is a predictor of future ill health in family members, as shown by the associations between passive smoking and cardiorespiratory health in cohabiting adults and between maternal smoking and reduced FEV1 in adult offspring. The prevalences of chronic sputum production and cigarette smoking have fallen between the generations, while the prevalences of hay fever and atopic asthma increased. These trends and the aggregation of respiratory impairment within families provide many opportunities for further investigation.