Gestational Weight Gain linked to Allergic Diseases in children: JAMA

Childhood allergic diseases are considered to originate in the periconceptional period. Maternal prepregnancy, body mass index (BMI) and excessive GWG during pregnancy can alter the intrauterine environment, which may affect the development of the immune system of the fetus, thus leading to increased susceptibility to allergic diseases. Increased risk of childhood allergic diseases associated with high maternal BMI before pregnancy has been suggested in several cohort studies.

A rapid increase in the prevalence of childhood allergic diseases has also attracted global attention but, Information on the association between maternal prepregnancy body weight, gestational weight change, and childhood allergies is not consistent. Little is known on whether there is a combined association with comprehensive childhood allergies.

With such inconsistencies in mind, Yiting Chen et al, from School of Medicine, Shanghai Jiao Tong University, China, carried out a study to to examine the association of maternal prepregnancy body mass index and gestational weight gain (GWG) with the risk of childhood allergic diseases including asthma and/or wheezing, allergic rhinitis, eczema, and food and/or drug allergy.

The study design was a cross-sectional study, conducted from April 12 to June 1, 2019, using the Shanghai Children Allergy Study (SCAS), a large, population-based survey. A multistage and Multistrata sampling approach was applied to survey 13 districts across Shanghai, China, with an enrollment of 15 145 mother-child pairs.

The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire, which is commonly used among preschool and school-aged children, was adopted to evaluate childhood allergic diseases.

Based on World Health Organization guidelines modified for Asian people, mothers who participated in the survey were categorized into 4 groups: underweight (BMI <18.5), normal weight (BMI, 18.5-22.9), overweight (BMI, 23.0-24.9), and obese (BMI >25.0).

On analysis, the following key facts emerged.

• Among 15 145 children aged 3 to 14 years (7911 [52.2%] boys) within the SCAS, 8877 children (58.6%) were screened for allergic diseases.
• Multivariable log-binomial regression models suggested that excessive GWG was associated with risks of 19% for asthma/wheezing, 11% for allergic rhinitis, and 10% for eczema in the children.
• Gestational weight gain extremely above the Institute of Medicine guideline in women who were overweight/obese before pregnancy was associated with the highest risk of childhood asthma/wheezing (adjusted prevalence ratio, 1.42; 95% CI, 1.16-1.74; P = .001), allergic rhinitis (adjusted prevalence ratio, 1.32; 95% CI, 1.12-1.56; P = .001), and eczema (adjusted prevalence ratio, 1.24; 95% CI, 1.08-1.41; P = .002).
• Gestational weight gain below the Institute of Medicine guideline was associated with an attenuated risk of 13% for childhood asthma/ wheezing, 11% for allergic rhinitis, 14% for eczema, and 15% food/drug allergy when mothers were of prepregnancy normal weight; similar associations were observed in underweight mothers, but there was no association in overweight mothers.

"To our knowledge, this is the first study exploring the association of maternal prepregnancy BMI and GWG with childhood allergies in a low-income country. Further studies on the long-term effects of the intrauterine environment on children's health may take maternal weight management during pregnancy into consideration since GWG could be a controllable and modifiable risk factor. "wrote the research team.

For the full article, click on the link: 10.1001/jamanetworkopen.2020.15643

Primary source: JAMA Network Open.