The Survival Advantage of Patients with Cystic Fibrosis Diagnosed Through Neonatal Screening: Evidence from the United States Cystic Fibrosis Foundation Registry Data

Objective

To determine the impact of age and condition at the time of diagnosis on survival of patients with cystic fibrosis (CF).

Study design

By mode of diagnosis, 27,692 patients documented in the 1986–2000 CF Foundation Registry were segregated into meconium ileus (MI), prenatal or neonatal screening (SCREEN), positive family history only (FH), and symptoms other than MI (SYMPTOM). Patients in the MI, SCREEN, and SYMPTOM groups were further categorized by initial presenting symptoms into combined respiratory symptoms and malnutrition (RESP + NUTR), RESP, NUTR, other less common symptoms (OTHER), and OTHER + RESP/NUTR.

Results

Fifty-five percent of patients in the SCREEN group and 59% of patients in the MI group were diagnosed within age 1 month, as contrasted with 5% in patients in the SYMPTOM group (P < .001). Compared with patients in the SCREEN group, patients in the MI and SYMPTOM groups had significantly greater risks of shortened survival. Patients in the SYMPTOM group presenting with RESP + NUTR had significantly greater risk of shortened survival than the SCREEN group (P < .05). Survival of patients in the SYMPTOM group diagnosed “early,” that is, within 1 month of age, did not differ from patients in the SCREEN group but was significantly better than patients in the SYMPTOM group diagnosed beyond age 1 month to 10 years.

Conclusions

Early diagnosis through screening is associated with better survival compared with delayed diagnosis through non-MI symptoms beyond the age of 1 month.

CF, Cystic fibrosis, CI, Confidence interval, FH, Group of patients with a positive family history without symptoms, NBS, Newborn screening, NUTR, Group of patients with symptoms of malabsorption and malnutrition, MI, Group of patients with meconium ileus, HR, Hazard ratio, RESP, Group of patients with respiratory symptoms, SCREEN, Group of patients without meconium ileus and identified via prenatal/neonatal screening, SYMPTOM, Group of patients with symptoms other than MI