Body Mass Index and the Related Factors among Children with Asthma

Background: Asthma is the most common chronic diseases among children world in the past 30 years. The incidence has increased steadily. According to the survey data showed that the prevalence of asthma in Taipei elementary school children has reached 20.34%. Therefore, asthma has become a chronic childhood illness care focus. Recent researches indicate relationship between obesity and asthma. Many researchers are trying to explore whether is common gene between the two, in a common environment fetal environment or living together. When asthma combined with obesity, they will in addition to the impact of disease control, but overall health of children negative impact also. Aim: This study is aimed to understand body mass index of asthma children, and then to compared with the normal students. The potential related factors of home-school environments, energy balance-related behaviors and health status are explored to understand how they affect body mass index of asthma children. Methods: This quantitative study adopted a cross-sectional survey method by means of a purposive sampling method to recruit subjects in the allergy and rheumatic clinic of a northern medical center during September 1, 2014 to December 27, 2014,. The inclusion criteria was children aged 6-12 years, diagnosed with asthma for children, the asthma persisted more than a year, their parents or legal representatives agree to participate the researchers. The parents of recruited children who were able to read Chinese and agree to complete this researcher were also invited to join the study. Research instrument of a structured questionnaire developed by Gau et al. (2014) was used to collect the data. The contents included demographic data of children and their parents, home-school environmental data, the energy balance–related behaviors of children and health status of children. In addition, field measurement and recording of height and weight of children and their parents, to calculate the body mass index. The median value (50th percentile BMI) was the baseline by taking the reference of new growth curve of Taiwan children and adolescents from Chen & Chang (2010). The adjusted median of BMI of the body mass index was a continuous variables to compare differences of independent variables between groups of above (including the median) and below the median. Research data analysis was using SPSS statistical software package version 17. R3.1.3 carried frequency allocation table, percentage, mean, standard deviation, median and other descriptive statistics, but also for independent samples t test, Wilcoxon rank-sum test, Fisher Exact test univariate test, and further analysis of variance, linear regression models, generalized additive model of multivariate analysis. Results: Effective sample size in this study were collected 118 pairs of children and parents, and finally into the statistical analysis of 113 pairs. Where 67 boys (59.3%) and 46 girls (40.7%), with an average age of 8.98 years (SD ± 1.84), the average number of years of suffering from asthma 3.94 years (SD ± 2.43), and found that 15 people were overweight (13.27%), and 10 people were obese (8.85%). Then follow the age division, child overweight at the age of 8 was the most (31.25%), obese at the age of 10 up to 20.00%. The average age of parents 41.03years (SD ± 5.36), 59 were overweight (26.11%), 23 were mildly obese (10.18%), 17 were moderately obese (17.52%), and 2 were severe obesity (.88%). In this study, three generalized additive three models were explored, the third model explained total variance of 78.36%. The independent variables significantly affect the child BMI were: (A), demographic variables: boy, age older than 8.18, were hyperactive disorder or attention-deficit, mother’s gestation more 39.52 weeks are significant positive correlated with children''s BMI, but atopic dermatitis and BMI was significantly negatively correlated. (B), home-school environmental factors: parents aged between 31.02 to 42.21, parents BMI, lunch prepared by their families, walking school spending .304 to 11.011 minutes with the children significant positive correlation between BMI, but the highly educated father, low levels of education mother, walking and riding for children or family car was significantly negatively correlated with BMI. (C), children''s energy balance-related behavioral factors: high oil and high sugar intake less than 1.59 days/week, meat intake ranged from 0.43 to 2.25 days/week, milk and egg intake ranged from 1.72 to 3.62 days/week, fruits and vegetables intake between 3.97 to 6.15 days/week, probiotics less than .112 days/week and ranged from 1.121 to 2.752 days/week, ice cream drinks greater than .284 day/week, and holiday sleep time between 8.217 to 10.696 hours, were significantly positively e related to children BMI. (D), children''s health status factors: wheezing or coughing caused by overactive exercise, visits to emergency department more than 2 times a year, and asthma related hospitalization during past one year was negatively correlated with BMI. Conclusion: This study indicates the proportion of overweight and obese asthma children is lower than the domestic health children, but according to the growth curve study among children and adolescents in Taiwan of Chen & Chang (2010), regardless of gender, the average BMI of asthma children are higher than the median. Asthma child weight problems still need our attention. The significant affecting factors to asthma children''s body mass index confirmed in this study, will give reference to understand and prevent the asthma potential health risk for children. It is hoped to provide the valuable references of disease control and weight management for clinical health providers, school educators and health educators to help children and parents get insights of home-school environmental factors, to build a healthy lifestyle for children with asthma to effectively control their disease and to promote health status.