Cystic fibrosis mortality trend in Italy from 1970 to 2011

Survival in cystic fibrosis (CF) has progressively improved and the female-gender disadvantage first described many years ago remains controversial.

To describe the mortality trend due to CF in Italy over the last decades; to verify the female-mortality disadvantage; to compare the comorbidities reported in death certificates of CF patients with those of the general population.

Mortality data were extracted from the database of underlying cause of death (1970-2011) and multiple causes of death (2003-2011) of the Italian National Institute of Statistics. Age-standardized mortality ratio (SMR) was calculated to compare the mortality between genders. The association between CF and other contributing causes of death was verified by calculating the age- and gender-adjusted proportional mortality ratio (PMR).

During the study period, 1947 death certificates reported CF as the underlying cause of death. Mortality rate due to CF decreased in newborns and children and by the end of the 1990s also in adolescents and young adults. Adult mortality started to increase in the early 1990s. Over the whole period an excess in mortality was observed in young CF females (1-29 years). The multiple causes of death database included 531 certificates with CF listed as cause of death. Pneumonia, chronic lower respiratory diseases, pulmonary heart disease and diseases of pulmonary circulation, aspergillosis, sepsis, renal failure, diabetes, malnutrition and amyloidosis were more frequently reported in CF death certificates compared to those of the general population (PMR>1).

This mortality trend provides evidence of a consistent improvement in survival, although the excess female-mortality persists despite aggressive treatment of CF lung disease. Several extra-pulmonary conditions associated with CF contributed to the morbidity leading to death.