Asians with cystic fibrosis in the UK have worse disease outcomes than clinic matched white homozygous delta F508 controls.

Background: We tested the hypothesis that the Asian cystic fibrosis (CF) phenotype is comparable to the commonest genetic form of CF found in 50% of the white UK CF population using the UK CF Database, a national disease-specific patient registry.

Methods: 50 Asian CF patients were matched by Centre with 143 white homozygous delta F508 patients for gender, age and chronic Pseudomonas aeruginosa status (a marker of morbidity). The authors compared FEV1 and FVC% predicted, mean height, weight and BMI Z scores.

Results: FVC% predicted, weight and BMI Z scores were significantly worse in the Asians. Asian male/female FVC% predicted (p-value, 95% CI) -15.1 (p=0.001, -24.0, -8.8)/-15.2 (p=0.014, -27.1, -3.3) compared with white controls. Asian females also had significantly worse FEV1% predicted compared with controls (-14.9, p=0.025, 95% CI: -27.8, -2.0). Asians had significantly lower raw Z scores for weight (males p=0.002, females p=0.013) and BMI (males p=0.002, females p=0.008).

Conclusions: These data suggest that the Asian CF phenotype is as severe as the white controls with the homozygous delta F508 phenotype but is worse in some outcomes, especially in Asian females. Socio-cultural factors and rare CF genotypes may contribute to the severity of CF in this vulnerable group.