This accumulation of mucus can impair the pancreas and, secondarily, the intestine. Mucous build-up in lungs tends progressively to impair respiration. Without treatment, CF results in death for 95% of affected children before age 5. However, with diligent medical care patients with CF are surviving even beyond middle age.
Early diagnosis of CF is of great importance. Early and continuing treatment of CF is essential for long-term survival. However, as more people with CF survive childhood, new problems are emerging. For example, 68% of 75 adult women with CF reported leakage of urine within the past year. Coughing, sneezing, laughing and airway clearance provoked the leakage, which was worse when their chest disease was most severe.
CF is inherited in an autosomal recessive manner and affects both boys and girls. One in 400 white couples is at risk for having children with CF and their risk with each pregnancy is 1 in 4, so (multiplying 1 in 400 times 1 in 4) the overall risk that their child will have CF is 1 in 1600. Note that once a couple has had a CF child, the risk that each of their subsequent children will have CF drops to 1 in 4 (25%).