Association between socioeconomic status, sex, and age at death from cystic fibrosis in England and Wales (1959 to 2008): cross sectional study

Objective To determine the trend in the association between socioeconomic status and sex and median age at death from cystic fibrosis in England and Wales, over the past 50 years. Design Series of annual cross sectional studies of all registered deaths with a diagnosis of cystic fibrosis in England and Wales, from 1959 to 2008. Methods We obtained national mortality data for cystic fibrosis from the Office for National Statistics. From 1959 to 2000, the Registrar General’s Social Class coded socioeconomic status as manual or non-manual. From 2001 onwards, the National Statistics Socioeconomic Classification was implemented and socioeconomic status was split into three groups: professional and managerial, intermediate, and routine and manual. We calculated median age at death for every study year. We calculated the effects of sex and socioeconomic status on the odds of death above the median age at death for every study decade using logistic regression. Results From 1959 to 2008, 6750 deaths were attributed to cystic fibrosis in England and Wales. Males were more likely to die above the annual median age at death than females (from 1959 to 1999, adjusted odds ratio for socioeconomic status 1.28, 95% confidence intervals 1.13 to 1.45; from 2000 to 2008, 1.57, 1.18 to 2.08). Individuals in the highest socioeconomic class were also more likely to die above the median age of death than those in the lowest socioeconomic class (from 1959 to 2000, adjusted odds ratio for sex 2.50, 2.16 to 2.90; from 2001 to 2008, 1.89, 1.20 to 2.97). Conclusions Socioeconomic status and sex remain strong determinants of survival from cystic fibrosis in England and Wales, and the magnitude of these effects does not appear to have substantially reduced over time.