Being overweight in childhood, puberty, or early adulthood: Changing asthma risk in the next generation?
Authors: Ane Johannessen, Marianne Lønnebotn, Lucia Calciano, Bryndis Benediktsdóttir, Randi Jacobsen Bertelsen, Lennart Bråbäck, Shyamali Dharmage, Karl A. Franklin, Thorarinn Gislason, Mathias Holm, Christer Janson, Deborah Jarvis, Rain Jõgi, Jeong-Lim Kim, Jorunn Kirkeleit, Caroline Lodge, Andrei Malinovschi, Jesus Martinez-Moratalla, Roy Miodini Nilsen, Antonio Pereira-Vega, Francisco Gómez Real, Vivi Schlünssen, Simone Accordini, Cecilie Svanes
Journal: Journal of Allergy and Clinical Immunology (2019)

BackgroundOverweight status and asthma have increased during the last decades. Being overweight is a known risk factor for asthma, but it is not known whether it might also increase asthma risk in the next generation.ObjectiveWe aimed to examine whether parents being overweight in childhood, adolescence, or adulthood is associated with asthma in their offspring.MethodsWe included 6347 adult offspring (age, 18-52 years) investigated in the Respiratory Health in Northern Europe, Spain and Australia (RHINESSA) multigeneration study of 2044 fathers and 2549 mothers (age, 37-66 years) investigated in the European Community Respiratory Health Survey (ECRHS) study. Associations of parental overweight status at age 8 years, puberty, and age 30 years with offspring's childhood overweight status (potential mediator) and offspring's asthma with or without nasal allergies (outcomes) was analyzed by using 2-level logistic regression and 2-level multinomial logistic regression, respectively. Counterfactual-based mediation analysis was performed to establish whether observed associations were direct or indirect effects mediated through the offspring's own overweight status.ResultsWe found statistically significant associations between both fathers' and mothers' childhood overweight status and offspring's childhood overweight status (odds ratio, 2.23 [95% CI, 1.45-3.42] and 2.45 [95% CI, 1.86-3.22], respectively). We also found a statistically significant effect of fathers' onset of being overweight in puberty on offspring's asthma without nasal allergies (relative risk ratio, 2.31 [95% CI, 1.23-4.33]). This effect was direct and not mediated through the offspring's own overweight status. No effect on offspring's asthma with nasal allergies was found.ConclusionOur findings suggest that metabolic factors long before conception can increase asthma risk and that male puberty is a time window of particular importance for offspring's health. Overweight status and asthma have increased during the last decades. Being overweight is a known risk factor for asthma, but it is not known whether it might also increase asthma risk in the next generation. We aimed to examine whether parents being overweight in childhood, adolescence, or adulthood is associated with asthma in their offspring. We included 6347 adult offspring (age, 18-52 years) investigated in the Respiratory Health in Northern Europe, Spain and Australia (RHINESSA) multigeneration study of 2044 fathers and 2549 mothers (age, 37-66 years) investigated in the European Community Respiratory Health Survey (ECRHS) study. Associations of parental overweight status at age 8 years, puberty, and age 30 years with offspring's childhood overweight status (potential mediator) and offspring's asthma with or without nasal allergies (outcomes) was analyzed by using 2-level logistic regression and 2-level multinomial logistic regression, respectively. Counterfactual-based mediation analysis was performed to establish whether observed associations were direct or indirect effects mediated through the offspring's own overweight status. We found statistically significant associations between both fathers' and mothers' childhood overweight status and offspring's childhood overweight status (odds ratio, 2.23 [95% CI, 1.45-3.42] and 2.45 [95% CI, 1.86-3.22], respectively). We also found a statistically significant effect of fathers' onset of being overweight in puberty on offspring's asthma without nasal allergies (relative risk ratio, 2.31 [95% CI, 1.23-4.33]). This effect was direct and not mediated through the offspring's own overweight status. No effect on offspring's asthma with nasal allergies was found. Our findings suggest that metabolic factors long before conception can increase asthma risk and that male puberty is a time window of particular importance for offspring's health.