Association between dietary choline intake and asthma and pulmonary inflammation and lung function: NHANES analysis 2009–2018

Asthma is a chronic inflammatory condition, and choline may alleviate airway inflammation and oxidative stress but studies on the association between dietary choline and asthma remain limited. The purpose of this study is to investigate the associations between dietary choline intake and asthma, as well as pulmonary inflammation and lung function in children and adults. In our research, we employed the data of the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2018, including 7,104 children and 16,580 adults. We used fractional exhaled nitric oxide (FENO) to assess pulmonary inflammation and forced expiratory volume in one second (FEV1), forced vital capacity (FVC), the FEV1/FVC ratio, peak expiratory flow rate (PEF), predicted FEV1% and predicted FVC% to assess lung function. Binary logistic regression, linear regression, and the restricted cubic splines were used to analyze the associations between dietary choline intake and asthma and pulmonary inflammation and lung function. In children, we observed the positive associations between the natural logarithmic transformation of choline (ln-choline) and ln-FEV1 [ β:0.011; 95%CI: (0.004,0.018)] and ln-FVC [ β:0.009; 95%CI: (0.002,0.016)]. In adult males, the ln-choline was positively associated with ln-FEV1[ β:0.018; 95%CI: (0.011,0.024)], ln-FVC [ β:0.020; 95%CI: (0.014,0.026)], ln-PEF [ β:0.014; 95%CI: (0.007,0.022)], ln-predicted FEV1% [ β: 0.007; 95%CI: (0.001, 0.013)] and ln-predicted FVC%[ β: 0.010; 95%CI: (0.005, 0.015)] and negatively associated with FENO [ β: -0.029; 95%CI: (-0.049, -0.009)]. In unadjusted and partially adjusted models, adult females with ln-choline in the highest quartile had 25.2% (95%CI:9.4-38.3%) and 23.8% (95%CI:7.6-37.1%) decreased odds of asthma compared to those with the lowest quartile group. In the dose-response relationships of dietary choline and pulmonary inflammation and lung function indicators in adults, there existed threshold and saturation effects. The associations between dietary choline and lung function indicators such as FEV1 and FVC are positive in children and adults. The association between dietary choline and pulmonary inflammation is negative only in adults.