Up to the present time accumulated experience with cystic fibrosis has been based on intensive study of relatively small groups of patients treated or seen for the disease in a few leading clinics in the country. This paper presents, for the first time, characteristics of patients with cystic fibrosis from a sample of hospitals throughout the continental United States. Estimates are based on sample data for 1957. The more important findings follow.
Almost 70% of the estimated 2,500 patients with cystic fibrosis were discharged from hospitals in the Northeast and North Central regions of the United States. Only 9% of all cases were reported by hospitals in the West.
Among hospitals approved for pediatric residency, discharges were more equally distributed between the four regions than among other types of hospitals. Almost half of the estimated 1,320 patients in non-pediatric residency hospitals were in the North Central region alone.
Eighty-five per cent of hospitalized patients were under 10 years of age; approximately 30% were infants. About 5% were aged 20 years or more. In hospitals approved for pediatric residency, slightly over 1% of patients were aged 20 years or more, whereas, in other types of hospitals, 8% were were in the oldest age group.
For every 100,000 children in the population under 21 years of age, about 4 were hospitalized for cystic fibrosis in 1957. Among children under 1 year of age, the rate for hospitalization due to cystic fibrosis was 18 per 100,000 live births in 1957; the rate was 8 per 100,000 in the child population under 5 years of age; for children 5 to 9 and 10 to 20 years, rates were about 3 and 1 respectively.
There was a significant regional variation in rates for hospitalization because of cystic fibrosis. Whereas in both the Northeast and North Central regions there were about 5 patients under 21 years of age per 100,000 in the population under 21 years, there were only about 2 cases per 100,000 population in the same age group in both the South and West.
For each of the four regions, the ratio of hospitalized cases of cystic fibrosis to child population was highest in the age group under 5 years. In the Northeast there were 11 children for every 100,000 in the population under 5 years of age hospitalized for cystic fibrosis; in the North Central region there were 10 children; in the South there were 5, and in the West, 4 children.
Almost 15% of the 2,500 hospitalized patients with cystic fibrosis were discharged by death. Of the 360 patients with fatal cases, about 40% died during infancy; almost 25% died at ages 1 to 4 years; about the same proportion died at ages 5 to 9 years.
The ratio of deaths from the disease per 100 cases hospitalized during the year was 18 for infants, 12 for children in the age group 1 to 4 years, 14 for children 5 to 9 years, and 12 for those aged 10 years or more.
According to survey data, a larger number of males than females in each age group were hospitalized for cystic fibrosis. Among fatal cases under 10 years of age, however, the number of females slightly exceeded the number of males.
More than one-third of the 2,500 patients had been previously discharged from the hospital reporting the case either in the same year or in some prior period. About 6% of all patients were discharged from the same hospital at least three times during 1957.
Among the 360 patients discharged by death, over half were discharged two or more times during their lifetime from the hospital reporting the case. Among the 2,140 discharged alive, only about a third were reported to have multiple discharges from the same hospital.
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