Relationship among genetic variants, obesity traits and asthma in the Taiwan Biobank

Abstract

Background and objectiveObesity and asthma impose a heavy health and economic burden on millions of people around the world. The complex interaction between genetic traits and phenotypes caused the mechanism between obesity and asthma is still vague. This study investigates the relationship among obesity-related polygenic risk score (PRS), obesity phenotypes and the risk of having asthma.MethodsThis is a matched case–control study, with 4 controls (8288 non-asthmatic) for each case (2072 asthmatic). Data were obtained from the 2008–2015 Taiwan Biobank Database and linked to the 2000–2016 National Health Insurance Research Database. All participants were ≥30 years old with no history of cancer and had a complete questionnaire, as well as physical examination, genome-wide single nucleotide polymorphisms and clinical diagnosis data. Environmental exposure, PM2.5, was also considered. Multivariate adjusted ORs and 95% CIs were calculated using conditional logistic regression stratified by age and sex. Mediation analysis was also assessed, using a generalised linear model.ResultsWe found that the obese phenotype was associated with significantly increased odds of asthma by approximately 26%. Four obesity-related PRS, including body mass index (OR=1.07 (1.01–1.13)), waist circumference (OR=1.10 (1.04–1.17)), central obesity as defined by waist-to-height ratio (OR=1.09 (1.03–1.15)) and general–central obesity (OR=1.06 (1.00–1.12)), were associated with increased odds of asthma. Additional independent risk factors for asthma included lower educational level, family history of asthma, certain chronic diseases and increased PM2.5exposure. Obesity-related PRS is an indirect risk factor for asthma, the link being fully mediated by the trait of obesity.ConclusionsObese phenotypes and obesity-related PRS are independent risk factors for having asthma in adults in the Taiwan Biobank. Overall, genetic risk for obesity increases the risk of asthma by affecting the obese phenotype.

Obesity-related asthma: new insights leading to a different approach

“…There is little evidence of shared genetic correlation between BMI and early-onset asthma. In a recent case -control study using data from a Taiwan Biobank cohort, the obese phenotype was associated with a higher chance of developing asthma by approximately 26% [9]. Other independent risk factors for asthma included lower educational level and increased PM2.5 exposure.…”

“…A sedentary lifestyle as well as change in diet may have contributed to this increase [1,3,4]. Several epidemiological [4][5][6][7] and genetic [8][9][10] studies have shown a strong association between asthma and obesity although the direction of causality is still subject to debate [1]. In younger patients, asthma may lead to obesity due to lifestyle change and effect of corticosteroids, whereas in adult-onset asthma patients, obesity often precedes asthma [1].…”

Asthma exacerbations and body mass index in children and adolescents: experience from a tertiary care center

“…This relationship between asthma and obesity can be explained by various different aspects including, but not limited to, duration of obesity [9], presence of significant co-morbids, common in utero conditions, and common predisposing dietary factors [13]. Furthermore, there is significant evidence that obesity and asthma may share the same genetic risk factors [14,15].…”