Occurrence, outcomes and predictors of portal hypertension in cystic fibrosis: A longitudinal prospective birth cohort study

Abstract

Background: The reported prevalence of portal hypertension (PH) in Cystic Fibrosis is variable, incidence rates rarely provided and the utility of liver function tests (LFT's) early in life to predict PH is questionable. The aims were to (1) determine PH prevalence (P) and incidence rate (IR) and combined mortality transplant (MTX) data in PH vs non-PH patients and (2) to assess association of LFTs in early life with liver disease and PH.

Method: (1) A double centre longitudinal cohort study of 577 CF patients diagnosed by newborn screening (NBS) with annual examinations for PH up to 18.5 years of age (max) was performed over 28 years for P, IR, and MTX data; (2) Cox proportional hazard models were used to assess the association of elevated LFTs on 2 or more occasions over 0-6.5 years and PH.

Results: 51/577(8.8%) developed PH with an average IR of near 3/1000 patient years per 5 year interval representing young, mid and late childhood respectively in patients 3-18 years of age. Combined mortality/liver transplant occurred in 12/51 (23.5%) PH and 25/526 (4.8%) non-PH (p < 0.001). Elevated enzymes particularly GGT (HR:5.71, 95% CI 3.11-10.47); ALT/GGT (HR: 5.56, 95% CI 2.82-10.98); and ALP/GGT (HR: 5.74, 95% CI 2.78-11.86) were associated with the onset of PH.

Conclusion: This birth cohort with annual examination for PH provides an accurate assessment of the prevalence, and IR of PH and MTX of PH vs non-PH. Early elevated LFTs are associated with onset of MBC/PH.

Keywords: Incidence/Prevalence; Liver enzymes; Portal hypertension.