ABSTRACT
The purpose of the present study was to identify prognostic factors related to death in patients with cystic fibrosis (CF). Records of 127 patients with CF submitted to a systematic protocol were retrospectively reviewed. Prognostic factors associated with demographic, nutritional, clinical, and laboratory findings on admission were studied. The median follow-up was 44 months. The analysis was conducted in two steps. First, in a univariate analysis, variables associated with death outcome were identified by the log-rank test. Then the variables that were significantly associated with adverse outcome were included in a multivariate analysis. This analysis, using the Cox proportional hazards model, was performed to identify variables that were independently associated with a worse prognosis. Only variables that remained independently associated with adverse outcome were included in the final model. Three variables were identified as independent predictors of adverse outcome: age at diagnosis under 3 months (relative risk (RR) = 13, 95% CI = 4.5-34, P < 0.001); Shwachman-Kulczycki (S-K score) score below 70; and birth weight under 3,000 g. An interaction effect between S-K score and birth weight was identified. The relative risk of death for the S-K score was 24 (95% CI = 3-195) when birth weight was lower than 3,000 g; on the other hand, when birth weight was 3,000 g or more, the relative risk for the S-K score was 1.4 (95% CI = 0.24-8.83). The combination of three factors (low S-K score, low birth weight, and young age at diagnosis) is indicative of a poor prognosis in CF patients.
