The Relationship Between Sleep Time And Physical Growth In Children: A Systemic Review

Background:In recent years, with the improvement of social economy and the living standards, growth levels of children of cities in China are near the standards of growth in the developed countries. Some shifts in the spectrum of diseases are noted. The concept of health was gradually changed from the biological medical patterns to biological psychological patterns. People like to live and also health. They pay more attention to the children's life quality. Sleep problems of children is associated with the life quality. And it is related to the physical growth and behavioral development of children. As we know, some hormones are secreted during sleep, such as human growth hormone. People are interested in the sleep time and physical growth of children. In recent 20 years about 30 epidemiological articles were published with different results about the relationship between sleep time and physical growth in children.Objectives:To analyze the literature about the relationship between sleep time and physical growth in children in China.Search strategy:According to the unified retrieval strategy and retrieval methods, a literature search was performed among VIP,CBM, CNKI and Wanfang database till February 2011, supplemented by manual search. Grey literature were not included.Inclusion criteria:All studies published in Chinese and reported the relationship between sleep time and physical growth in children, including studies that with objects for 0-18 children in China only;use the height and (or) weight to evaluate the physical growth of children.Results:A total of 249 articles were screened, we did not find any existing cohort study. Finally 27 studies were involved in our analysis. 17 studies (63%) show that sleep time is related to physical growth in children, 10 studies(37%) show childhood obesity and sleep time is irrelevant.According to the quality assessment of included studies,19 studies(70.4%) are grade B,8 studies (29.6%) are grade C,none is grade A.Conclusions:The relationship between sleep time and physical growth in children is not clear.From the 27 studies we can not find the cause-and-effect relationship between the time of sleep and growth of children.And further studies should be designed according to normative and large multicenter prospective cohort studies or randomized controlled trials.If possible animals sleep experiment model can help to understand the mechanism.