Effect of polyunsaturated fatty acids intake on the occurrence of current asthma among children and adolescents exposed to tobacco smoke: NHANES 2007-2018.

Background: Asthma is an airway inflammatory disease driven by multiple factors with a high incidence in children and adolescents. Environmental tobacco smoke exposure (TSE) and diet are inducing factors for asthma. The potential of omega-3 polyunsaturated fatty acids (PUFAs) to alleviate asthma symptoms by their anti-inflammatory effects has been explored. However, to date, no studies have explored the effect of dietary PUFAs intake on the asthma in children and adolescents exposed to tobacco smoke.

Objective: We aimed to examine the effect of dietary PUFAs intake on the current asthma in children and adolescents exposed to tobacco smoke.

Methods: Data of this cross-sectional were extracted from the National Health and Nutrition Examination Survey (NHANES) 2007-2018. Children and adolescents with serum cotinine concentration ≥ 0.05 ng/mL were defined to exposed to tobacco smoke. Dietary PUFAs intake information were obtained from 24 h recall interview. The weighted univariate and multivariate were utilized to explore the effect of PUFAs on the association of asthma and TSE, with adjusted odds ratios (AORs) and 95% confidence intervals (CIs). These moderating effects were further explored based on the age, gender and body mass index (BMI) and sedentary time.

Results: Totally, 7981 eligible children and adolescents were included, with the mean age of 11.96 ± 0.06 years old. Of whom, 1.024 (12.83%) had current asthma. After adjusted all covariates, we found children and adolescents with TSE had high occurrence of current asthma (AOR = 1.2, 95% CI 1.03-1.63); We also found omega-3 PUFAs intake (P for interaction = 0.010), not omega-6 PUFAs (P for interaction = 0.546), has a moderating effect on the association of TSE and current asthma. Moreover, we further observed that children and adolescents with TSE and low omega-3 PUFAs intake had high occurrence of current asthma (AOR = 1.58, 95% CI 1.19-2.10), while no significant association was found in children and adolescents with high omega-3 PUFAs intake (all P > 0.05). This moderating effect was more prominent in children and adolescents aged ≤ 12 years old (AOR = 1.62, 95% CI 1.06-2.47), girls (AOR = 2.14, 95% CI 1.15-3.98), overweight (AOR = 1.87, 95% CI 1.01-3.47) and sedentary time > 6 h (AOR = 1.96, 95% CI 1.00-3.86).

Conclusion: We found dietary omega-3 PUFAs plays a moderating effect on the association of asthma and TSE in children and adolescents, especially in children and adolescents aged ≤ 12 years, girls, overweight or sedentary time > 6 h. This moderating effect suggested higher omega-3 intake has potential benefits in decreasing the occurrence of asthma in children and adolescents who exposed to tobacco smoke.