Chest. 2012 Feb 23. [Epub ahead of print]
Are measures of body habitus associated with mortality in cystic fibrosis?
Fogarty AW, Britton J, Clayton A, Smyth A.
Nottingham Biomedical Research Unit, Division of Epidemiology and Public Health, University of Nottingham, Clinical Sciences Building, City Hospital, Nottingham NG5 1PB, UK.
Nutrition is an important component of clinical care for patients with cystic fibrosis. We aimed to test the hypothesis that increased body mass index (BMI), height and creatinine as a biomarker for lean muscle mass were associated with lower mortality, and whether differences in these measures may contribute towards gender differences in survival in cystic fibrosis.
We used a cohort study design using data from the UK Cystic Fibrosis Registry who attended an annual assessment visit in 2007 and were followed up until July 2009.
Of 1517 individuals, 62 died during the follow up period. The odds of death was higher among those in the lowest quintile of serum creatinine compared to the rest of the study population (OR 3.28, 95% confidence interval (CI) 1.79 to 5.98). Increased height and higher BMI were also associated with lower risk of death. The higher mortality in females (OR 1.48, 95%CI: 0.93 to 2.34) was reversed by adjustment using the absolute values for these variables, the adjusted OR being 0.44 (95%CI: 0.21 to 0.90) after adjustment for height, BMI and serum creatinine but not by the use of gender specific values for these exposure variables.
Lower muscle mass, shorter stature and a low BMI are associated with increased mortality in cystic fibrosis. These measures of body habitus may contribute to the gender survival differences in individuals with cystic fibrosis.