Air pollution causes abnormal alanine aminotransferase levels in patients with chronic hepatitis B.

Background: To investigate the association between air pollution and abnormal alanine aminotransferase levels in patients with chronic hepatitis B treated with nucleotide/nucleoside analogs (NAs).

Methods: This cross-sectional study enrolled 1275 patients with chronic hepatitis B treated with nucleotide/NAs from 2019 to 2022 in Kaohsiung and analyzed the incidence and risk factors for abnormal alanine aminotransferase levels. Daily air pollutant concentrations were estimated for the year before enrollment.

Results: Abnormal alanine aminotransferase levels were observed in 1127 patients (88.4%) before treatment with nucleotide/NAs. Logistic regression analysis revealed that the strongest factor associated with abnormal alanine aminotransferase levels was the level of hepatitis B virus DNA (odds ratio/CI: 1.40/1.25-1.57; p < 0.001), followed by concentration of particulate matter ≤2.5 µm in diameter (1.05/1.02-1.08; p < 0.001) and liver cirrhosis (0.27/0.17-0.42; p < 0.001). Among patients without cirrhosis, logistic regression analysis revealed that the strongest factors associated with abnormal alanine aminotransferase levels were the level of hepatitis B virus DNA (odds ratio/CI: 1.52/1.28-1.82; p < 0.001) and concentration of particulate matter ≤2.5 µm in diameter (1.06/1.101-1.11; p = 0.01). Among patients with cirrhosis, logistic regression analysis revealed that the strongest factor associated with abnormal alanine aminotransferase levels was hepatitis B virus DNA level (odds ratio/CI: 1.28/1.12-1.48; p = 0.001).

Conclusion: Higher concentrations of particulate matter ≤2.5 µm in diameter caused elevated baseline alanine aminotransferase levels in patients with chronic hepatitis B receiving nucleotide/NA therapy. The impact of particulate matter ≤2.5 µm in diameter on abnormal alanine aminotransferase levels was particularly pronounced in patients without cirrhosis.