Improvements of lung function in cystic fibrosis.

Improved care for patients with cystic fibrosis (CF) has led to their improved survival. We analyzed retrospectively whether improvements in lung function (LF) could be detected in our CF patients over the decade 1980-1990. In 72 patients, 153 LF measurements were performed in their first year of life (1980-1991), and then 189 LF measurements were performed again in 60 of those patients during their sixth year of life (1987-1997). Regression analysis was performed on LF parameters at age 6 years. When adjusting for weight, height, gender, and LF in the first year of life, the date of subsequent measurement was positively associated with FEV(1) (P < 0.01) and MEF(50%) (P < 0.05) and negatively with FRC(pleth) (P < 0.05). The proposed model predicts a child's FEV(1) at age 6 to be 75% of predicted if born in 1980, but 108% of predicted when born in 1990. Improved CF care is the most likely explanation for this observation.