An epidemiological study on the associations between preeclampsia exposure, growth and physical activity in preschool age and subsequent allergy, asthma and lung function in late childhood

Background An adverse intrauterine environment may affect offspring immunology, including allergies, asthma and lung function, as well as offspring metabolism, including growth and development. A few studies have been reported on the associations between preeclampsia and these outcomes, but they have shown conflicting results. Furthermore, a possible association between childhood excessive weight/obesity and physical activity with allergies, asthma and lung function has been suggested, but, again, previous studies show conflicting results, and few longitudinal studies exist. Objectives (1) To study the associations of preeclampsia exposure with atopic sensitization, allergic rhinoconjunctivitis, atopic dermatitis, asthma and lung function in late childhood. (2) To study the associations of preeclampsia exposure with length/height, weight and body mass index (BMI) at several ages from birth to late childhood and waist circumference, waist-to-height ratio and skinfolds in late childhood. (3) To study the associations of weight-related anthropometric measurements at several ages from birth to late childhood and physical activity with allergies and asthma in late childhood. (4) To study the associations of weight-related anthropometric measurements at several ages from birth to late childhood with lung function in late childhood. Methods In a nested case control study, 229 children were exposed to preeclampsia (mild/moderate: n = 164, severe: n = 54, unknown severity: n = 11) and 385 were unexposed. Length/height were abstracted from medical records at birth, 3 and 6 months, 1 and 4 years, and measured along with waist circumference and skinfolds at 10.8 years (girls), 11.8 years (boys) and 12.8 years (both genders). Questionnaires on maternal and child data were administered to the mothers when the children were at the age of 10.8/11.8 years (girls/boys) and to the children at the age of 12.8 years (both genders). Specific IgE in serum and lung function were measured at the age of 12.8 years (both genders). Multiple regression analyses were performed to analyse the associations of mother’s preeclampsia, child weight, child BMI, and childhood physical activity with childhood growth, atopic sensitization, allergic rhinoconjunctivitis, asthma, atopic dermatitis and lung function. Results Severe preeclampsia exposure was associated with high-level atopic sensitization (sum of specific IgE in serum 2: 3.9 kU/l; the lower quartile of all sensitized children in the study) and with allergic rhinoconjunctivitis in the offspring. We did not find any association of preeclampsia with allergic rhinoconjunctivitis, atopic dermatitis or lung function. In boys, mild/moderate preeclampsia exposure was positively associated with length/height after 0.5 years; however, severe preeclampsia exposure was negatively associated with length/height at all ages. In girls, preeclampsia was negatively associated with length/height until 12 years of age. In both genders, preeclampsia exposure was in general negatively associated with weight and BMI during infancy and early childhood, but the association became positive in later childhood, except that for boys exposed to severe preeclampsia the negative association remained throughout childhood. Severe preeclampsia exposure was positively associated with waist-to-height ratio at 10.8/11.8 (girls/boys) years of age. We did not find any associations of preeclampsia exposure with skinfolds or waist circumference. BMI at 1 year of age and low physical activity at 3–6 years of age were positively associated with atopic sensitization at 12.8 years of age. Change in BMI from 1 to 4 years, BMI at 4 years and high physical activity at 6–10 years of age were positively associated with ever being diagnosed with atopic dermatitis at the age of 10.8/11.8 years (girls/boys). Low physical activity at 3–6 and 6–10 years of age were positively associated with ever being diagnosed with asthma at the age of 10.8/11.8 years (girls/boys). We did not find any associations of weight, BMI and physical activity with ever being diagnosed with allergic rhinoconjunctivitis at the age of 10.8/11.8 years (girls/boys), and current asthma at the age of 12.8 years (both genders), nor did we find any non-straight-line associations of the predictors with any of the outcomes of atopic sensitization, allergic rhinoconjunctivitis, atopic dermatitis or asthma. Birthweight and BMI at different ages throughout childhood were positively associated with forced vital capacity in percent of predicted (FVC %) and forced expiratory volume in the first second of predicted (FEV1 %) at 12.8 years of age. BMI, waist circumference, waist-to-height ratio and skinfolds at 12.8 years of age and the change in BMI from early to late childhood were positively associated with FVC % and FEV1 % and negatively associated with FEV1/FVC and forced expiratory flow at 25–75% of FVC/FVC. Interaction analyses showed that positive associations between anthropometrics other than BMI and lung function were mostly present in girls. Inverse U-shaped associations were found between BMI at the ages of 10.8/11.8 (girls/boys) and 12.8 years (both genders) and FVC % and FEV1 % at 12.8 years of age. Conclusions Preeclampsia exposure was positively associated with atopic sensitization and allergic rhinoconjunctivitis in late childhood, but not with atopic dermatitis, asthma or lung function. From birth to adolescence, length/height, weight and BMI trajectories differed between the genders depending on the severity of preeclampsia exposure. In general, preeclampsia exposure was negatively associated with length/height, and in girls positively associated with weight and BMI. BMI and physical activity in early childhood were positively associated with atopic sensitization, atopic dermatitis and asthma in late childhood. Body composition through childhood may influence lung function in late childhood, which may be physiological or associated with air flow limitation. Non-straight-line associations suggest a differential impact on lung function in normal-weighted and overweight children. Our results suggest that foetal life is a particularly sensitive period for subsequent growth and development of the immune system, and that growth during childhood may further influence allergic disease and lung function in late childhood. Understanding the impact of early life risk factors may enable preventing the development of allergic disease and unfavourable lung function and promote healthy growth