Pulmonary function test abnormalities in children and adolescents with non-alcoholic fatty liver disease

Association between pulmonary function tests (PFTs) and non-alcoholic fatty liver disease (NAFLD) has been reported in adult studies; however, there is lack of pediatric studies. Our study aimed to evaluate PFTs in children with NAFLD. A total of 137 children with NAFLD and 100 healthy children of matched age and sex were included in the study. Different PFTs including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC ratio, residual volume (RV), and total lung capacity (TLC) were performed for all included children. Lipid profile, insulin resistance, fasting and postprandial glucose level, and high sensitive C reactive protein (hs-CRP) were measured. FEV1 %, FVC %, FEV1/FVC ratio, RV, and TLC were significantly lower in the patient group compared with the control group (P < 0.05), while RV and hs-CRP were significantly higher in children with NAFLD. Restrictive lung dysfunction was the commonest pulmonary dysfunction detected in children with NAFLD (21.9%). PFT indices were significantly correlated with grade and duration of NAFLD, insulin resistance, waist circumference, and hs-CRP. Regression analysis revealed that insulin resistance and hs-CRP were independently associated with decreased PFT indices.Conclusion: PFT indices were impaired in children with NAFLD and this impairment was independently associated with insulin resistance and hs-CRP. What is Known: • Pulmonary function tests (PFTs) abnormalities are common in adults with nonalcoholic fatty liver disease (NAFLD). • Studies involving PFTs abnormalities in pediatric NAFLD are lacking. What is New: • It is the first study that assessed PFT in pediatric patients with NAFLD. • PFTs abnormalities are present in children with NAFLD. • Insulin resistance and high sensitive C reactive protein are independently associated with the decline of PFTs in children with NAFLD.