Diabetes as a Determinant of Mortality in Cystic Fibrosis

• Published in: Diabetes care Vol. 33; no. 2; pp. 311 - 316
• Main Authors: Chamnan, Parinya, Shine, Brian S.F, Haworth, Charles S, Bilton, Diana, Adler, Amanda I
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Diabetes Association 01.02.2010
• Subjects: Adolescent; Adult; Age Distribution; Age Factors; Aged; Biological and medical sciences; Child; Child, Preschool; Cohort Studies; Cystic fibrosis; Cystic Fibrosis - complications; Cystic Fibrosis - genetics; Cystic Fibrosis - mortality; Deaths; Diabetes; Diabetes Complications - mortality; Diabetes. Impaired glucose tolerance; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Errors of metabolism; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Female; Fibrosis; Genes, Recessive; Health care access; Humans; Hyperglycemia; Infant; Infant, Newborn; Male; Medical sciences; Metabolic diseases; Middle Aged; Miscellaneous; Miscellaneous hereditary metabolic disorders; Mortality; Original Research; Public health. Hygiene; Public health. Hygiene-occupational medicine; Registries; Retrospective Studies; Risk Factors; Staphylococcus infections; United Kingdom; United Kingdom - epidemiology; United Kingdom; Endocrinopathy; Human; Nutrition; Respiratory disease; Diabetes mellitus; Determinant; Mortality; Metabolic diseases; Cystic fibrosis; Epidemiology; Genetic disease; Digestive diseases; Endocrinology; Pancreatic disease
• ISSN: 0149-5992; 1935-5548
• DOI: 10.2337/dc09-1215

OBJECTIVE: Diabetes is increasingly common in cystic fibrosis, but little information describing its influence on mortality exists. Using national U.K. data, in this study we document diabetes-specific mortality rates, estimate the impact of diabetes on survival, and estimate population-attributable fractions. RESEARCH DESIGN AND METHODS: This retrospective cohort study identified 8,029 individuals aged 0-65 years from the U.K. Cystic Fibrosis Registry (1996-2005). A total of 5,892 patients were included in analyses of mortality rates, and 4,234 were included in analyses of risk factors. We calculated age-adjusted mortality rates using Poisson regression, standardized mortality ratios using the population of England and Wales, and relative risks using proportional hazards modeling. RESULTS: During 17,672 person-years of follow-up, 393 subjects died. The age-adjusted mortality rate was 1.8 per 100 person-years (95% CI 1.6-2.0). The age-adjusted mortality rates per 100 person-years were 2.0 (1.8-2.4) in female subjects and 1.6 (1.4-1.9) in male subjects, and 4.2 (3.4-5.1) in individuals with diabetes vs. 1.5 (1.3-1.7) in those without diabetes. Independent risk factors for death included diabetes (hazard ratio 1.31 [95% CI 1.03-1.67], female sex (1.71 [1.36-2.14]) plus poorer pulmonary function, lower BMI, Burkholderia cepacia infection, absence of Staphylococcus aureus infection, allergic bronchopulmonary aspergillosis, liver disease, prior organ transplantation, and corticosteroid use. CONCLUSIONS: Individuals with cystic fibrosis die earlier if they have diabetes, which, if delayed or better treated, might reasonably extend survival; this hypothesis merits testing.