Effects of Gender and Age at Diagnosis on Disease Progression in Long-term Survivors of Cystic Fibrosis

Rationale: Long-term survivors of cystic fibrosis (CF) (age > 40 yr) are a growing population comprising both patients diagnosed with classic manifestations in childhood, and nonclassic phenotypes typically diagnosed as adults. Little is known concerning disease progression and outcomes in these cohorts. Objectives: Examine effects of age at diagnosis and gender on disease progression, setting of care, response to treatment, and mortality in long-term survivors of CF. Methods: Retrospective analysis of the Colorado CF Database (1992 2008), CF Foundation Registry (1992-2007), and Multiple Cause of Death Index (1992-2005). Measurements and Main Results: Patients with CF diagnosed in childhood and who survive to age 40 years have more severe CFTR genotypes and phenotypes compared with adult-diagnosed patients. However, past the age of 40 years the rate of FEV1 decline and death from respiratory complications were not different between these cohorts. Compared with males, childhood-diagnosed females were less likely to reach age 40 years, experienced faster FEV1 declines, and no survival advantage. Females comprised the majority of adult-diagnosed patients, and demonstrated equal FEV1 decline and longer survival than males, despite a later age at diagnosis. Most adult-diagnosed patients were not followed at CF centers, and with increasing age a smaller percentage of CF deaths appeared in the Cystic Fibrosis Foundation Registry. However, newly diagnosed adults demonstrated sustained FEV1 improvement in response to CF center care. Conclusions: For patients with CF older than 40 years, the adult diagnosis correlates with delayed but equally severe pulmonary disease. A gender-associated disadvantage remains for females diagnosed in childhood, but is not present for adult-diagnosed females.