[Assessment of prevalence of malnutrition among Chinese primary and secondary school students and analysis of policy effect during the period of the Program for the Development of Chinese Children 2011-2020].

OBJECTIVE: To evaluate the change of prevalence of malnutrition among Chinese primary and secondary school students and to analyze the policy effect during the period of the Program for the Development of Chinese Children 2011-2020 (PDCC 2011-2020). METHODS: The data of Chinese students aged 7 to 18 years were extracted from 8 successive cross-sectional surveys of the Chinese National Survey on Students ' Constitution and Health (CNSSCH) from 1985 to 2019. Malnutrition of students was evaluated according to the screening standard for malnutrition of school-age children and adolescents. The changes of prevalence of malnutrition among primary and secondary school students were described by gender, urban and rural areas, age group and province, from 2010 to 2019. The Joinpoint regression model was used to analyze the trajectory of the prevalence of malnutrition among students aged 7 to 18 years from 1985 to 2019, so as to evaluate the policy effect of the PDCC 2011-2020. RESULTS: The prevalence of malnutrition among primary and secondary school students in China decreased from 12.7% in 2010 to 8.5% in 2019. The prevalence of malnutrition among boys and girls, urban and rural students, and students of all age groups showed a continuous downward trend (Ptrend < 0.001) from 2010 to 2019. From 2010 to 2019, 27 of the 31 provinces (autonomous regions and municipalities) saw a significant decrease in the prevalence of malnutrition among primary and secondary school students. Joinpoint regression model showed that the prevalence of malnutrition among Chinese primary and secondary school students continued to decline from 1985 to 2019, but 2010 was the turning point in the downward trend. From 1985 to 2010, the prevalence of malnutrition among primary and secondary school students decreased by an average of 2.4% per year (95%CI: 1.9%-2.8%, P < 0.001), and the downward trend accelerated after 2010, with an average annual decline of 4.3% (95%CI: 2.4%-6.2%, P < 0.001). CONCLUSION: The prevalence of malnutrition among primary and secondary school students in China continued to decline from 2010 to 2019, achieving the goal of controlling the prevalence of malnutrition among primary and secondary school students in the PDCC 2011-2020. The PDCC 2011-2020 may have played an important role in improving the malnutrition among primary and secondary school students. However, the problem of malnutrition among primary and secondary school students still exists, and it is still necessary to adhere to the coverage and financial support of the nutrition improvement plan in areas with high incidence of malnutrition.

[Association of outdoor artificial light at night exposure with overweight and obesity among children and adolescents aged 9 to 18 years in China].

OBJECTIVE: To analyze the association between outdoor artificial light-at-night (ALAN) exposure and overweight and obesity among children and adolescents aged 9 to 18 years in China. METHODS: Using follow-up data of 5 540 children and adolescents aged 9 to 18 years conducted from November 2019 to November 2020 in eight provinces of China, latitude and longitude were determined based on school addresses, and the mean monthly average nighttime irradiance at the location of 116 schools was extracted by the nearest neighbor method to obtain the mean outdoor ALAN exposure [unit: nW/(cm2·sr)] for each school. Four indicators of overweight and obesity outcomes were included: Baseline overweight and obesity, persistent overweight and obesity, overweight and obesity progression and overweight and obesity incidence. Mixed effects Logistic regression was used to explore the association between ALAN exposure levels (divided into quintiles Q1-Q5) and baseline overweight and obesity, persistent overweight and obesity, overweight and obesity progression and overweight and obesity incidence. In addition, a natural cubic spline function was used to explore the exposure response association between ALAN exposure (a continuous variable) and the outcomes. RESULTS: The prevalence of baseline overweight and obesity, persistent overweight and obesity, overweight and obesity progression and overweight and obesity incidence among the children and adolescents in this study were 21.6%, 16.3%, 2.9% and 12.8%, respectively. The OR value for the association between ALAN exposure and baseline overweight and obesity was statistically significant when ALAN exposure levels reached Q4 or Q5, 1.90 (95%CI: 1.26-2.86) and 1.77 (95%CI: 1.11-2.83), respectively, compared with the children and adolescents in the Q1 group of ALAN exposure. Similar to the results for baseline overweight and obesity, the OR values for the association with persistent overweight and obesity were 1.89 (95%CI: 1.20-2.99) and 1.82 (95%CI: 1.08-3.06) when ALAN exposure levels reached Q4 or Q5, respectively, but none of the OR values for the association between ALAN and overweight and obesity progression and overweight and obesity incidence were statistically significant. Fitting a natural cubic spline function showed a non-linear trend between ALAN exposure and persistent overweight and obesity. CONCLUSION: There is a positive association between ALAN exposure and overweight and obesity in children and adolescents, and the promotion of overweight obesity in children and adolescents by ALAN tends to have a cumulative effect rather than an immediate effect. In the future, while focusing on the common risk factors for overweight and obesity in children and adolescents, there is a need to improve the overweight and obesity-causing nighttime light exposure environment.

[Characteristics of autonomic neuropathy in patients with vestibular migraine].

Objective: To investigate the characteristics of autonomic neuropathy in patients with vestibular migraine (VM) by sympathetic skin reflex (SSR) and R-R interval variation (RRIV). Methods: Seventy-three patients with interseizure VM and 36 healthy controls in the Department of Neurology affiliated to Shanghai Fourth People's Hospital of Tongji University from November 1, 2019 to December 31, 2021 were prospectively enrolled. SSR and RRIV were performed and relevant parameters were recorded, including SSR latency, SSR amplitude, RRIV during calm breathing (R%), RRIV during deep breathing (D%), RRIV difference between deep breathing and calm breathing (D%-R%), RRIV ratio between deep breathing and calm breathing (D%/R%), and the difference and correlation of various parameters between VM patients and healthy controls were analyzed. Results: Among the 73 patients with VM, there were 12 males and 61 females, and aged (46±13) years. While among 36 healthy controls, there were 6 males and 30 females, and aged (46±7) years. Among the 73 VM patients, abnormal SSR, abnormal RRIV, abnormal SSR and RRIV, and abnormal SSR or RRIV was detected in 38 cases (52%), 17 cases (23%), 11 cases (15%) and 44 cases (60%), respectively. Compared with healthy controls, the lower extremity SSR latency [(1 719±289) ms] in VM patients was longer than that in control group [(1 500±349) ms] (P=0.001), but the upper extremity SSR amplitude [1.6 (0.8, 3.0) mV] was lower than that in control group [2.6 (1.8, 4.2) mV] (P=0.006). SSR amplitude, R% and D% were negatively correlated with age in VM patients (rs=-0.311, P=0.007; rs=-0.237, P=0.043; rs=-0.263, P=0.024, respectively). SSR of lower extremity in VM patients was longer than that of upper extremity [(1 719±289) ms vs (1 244±185) ms, P<0.001], but the amplitude of lower extremity was lower than that of upper extremity [0.8 (0.3, 1.7) mV vs 1.6 (0.8, 3.0) mV, P<0.001]. SSR latency of upper limb was positively correlated with SSR latency of lower limb (r=0.436, P<0.001), the amplitude of upper limb was positively correlated with amplitude of lower limb (rs=0.456, P<0.001), and D% was positively correlated with R% (rs=0.357, P=0.002). Conclusion: The autonomic neuropathy during VM interphase features with imbalance between sympathetic and parasympathetic nervous system, and the sympathetic nerve function is mainly impaired.

[Trends of age of menarche among Chinese Han girls aged 9 to 18 years from 2010 to 2019].

Objective: To analyze the trends of the age of menarche among Chinese Han girls aged 9 to 18 years from 2010 to 2019. Methods: Data were extracted from the Chinese National Surveys on Students' Constitution and Health in 2010, 2014 and 2019. A total of 253 037 Han girls aged 9 to 18 years with complete data on menarche were selected in this study. They were asked one-on-one about their menstrual status, age and residence information. The median age of menarche was estimated by probability regression. U tests were used to compare the difference in median age at menarche in different years. Results: The median age at menarche (95%CI) among Chinese Han girls was 12.47 (12.09-12.83) years in 2010, 12.17 (11.95-12.38) years in 2014 and 12.05 (10.82-13.08) years in 2019, respectively. Compared with that in 2010, the median age at menarche in 2019 decreased by 0.42 years (U=-77.27, P<0.001). The annual average changes were-0.076 years from 2010 to 2014 (U=-57.19, P<0.001) and-0.023 years from 2014 to 2019 (U=-21.41, P<0.001), respectively. The average annual changes in urban areas in the periods of 2010 to 2014 and 2014 to 2019 were-0.071 years and 0.006 years, respectively, while those in rural areas were-0.082 years and-0.053 years, respectively. The average annual changes in the regions of north, northeast, east, south central, southwest and northwest were-0.064, -0.099, -0.091, -0.080, -0.096 and-0.041 years in the period of 2010 to 2014 and 0.001, -0.040, -0.002, -0.005, -0.043 and-0.081 years in the period of 2014 to 2019. Conclusion: The age of menarche among Chinese Han girls aged 9 to 18 years shows an advanced trend from 2010 to 2019, and the trends in urban and rural areas and different regions have different characteristics.

[Prevalence trend of high normal blood pressure and elevated blood pressure in Chinese Han children and adolescents aged 7-17 years from 2010 to 2019].

Objective: To investigate the prevalence trend of high normal blood pressure and elevated blood pressure in children and adolescents aged 7 to 17 years in China from 2010 to 2019. Methods: Students aged 7-17 years were selected from the Chinese National Survey on Students' Constitution and Health from 2010 to 2019. High normal blood pressure and elevated blood pressure were determined according to the "Reference of screening for elevated blood pressure among children and adolescents aged 7-18 years" (WS/T 610-2018). The Chi-square test was performed to determine whether there was a difference in the prevalence of high normal blood pressure and elevated blood pressure by gender, residence and age group. Results: In 2019, the prevalence of high normal blood pressure in children and adolescents aged 7-17 years was 15.3% (29 855/195 625), which was higher in boys (20.2%, 19 779/97 847) and rural areas (15.4%, 15 066/97 567) than that in girls (10.3%, 10 076/97 778) and urban areas (15.1%, 14 789/98 058), respectively (all P<0.05). The prevalence of elevated blood pressure was 13.0% (25 377/195 625), which was higher in girls (13.2%, 12 925/97 778) and rural areas (14.1%, 13 753/97 567) than that in boys (12.7%, 12 452/97 847) and urban areas (11.9%, 11 624/98 058) (all P<0.05). From 2010 to 2019, the prevalence of high normal blood pressure showed an increasing trend, with an annual average growth rate from 1.14% to 3.18%. The overall prevalence of elevated blood pressure also showed an increasing trend from 2010 to 2019 but decreased in 2014. The annual average growth rate of elevated blood pressure was-1.07% from 2010 to 2014 and 9.33% from 2014 to 2019. About 17 provinces had an increasing trend in the prevalence of elevated blood pressure from 2010 to 2014, and 22 provinces with an increasing trend from 2014 to 2019. There were obvious regional differences in the annual average growth rate of the prevalence of high normal blood pressure and elevated blood pressure. The regions with the highest annual average growth rate of the prevalence of high normal blood pressure were the Northeast (5.47%) from 2010 to 2014 and the Western region (5.21%) from 2014 to 2019. For elevated blood pressure, the Northeast had the highest annual average growth rate from 2010 to 2014 (12.35%), while the Central (15.79%) and Western (12.87%) had the highest growth rate from 2014 to 2019. Conclusion: From 2010 to 2019, the prevalence of high normal blood pressure and elevated blood pressure in Chinese Han children and adolescents aged 7 to 17 shows an increasing trend, with regional disparities.

[Long-term trend of the age of spermarche and its association with nutritional status among Chinese Han boys aged 11-18 from 2010 to 2019].

Objective: To analyze the long-term trend of the age of spermarche among Chinese Han boys aged 11 to 18 from 2010 to 2019 and its association with nutritional status. Methods: The data from Chinese National Surveys on Students' Constitution and Health in 2010, 2014 and 2019 were used. The age, residence and spermarche of the participants were collected by questionnaire, and their height and weight were measured. A total of 184 633 Han boys aged 11‒18 years with complete data on spermarche, height, and weight were included in this study. The probability regression method was used to calculate the median age (95%CI) at spermarche in different areas, and the trend of age at spermarche in different groups was compared. The multivariate logistic regression model was used to analyze the association between nutritional status and spermarche of Chinese Han boys aged 11‒18 years. Results: The median age of spermarche (95%CI) was 13.85 (13.45-14.22) years old among Chinese Han boys aged 11‒18 years in 2019, with 0.18 years earlier than that in 2010. The median age at spermarche in urban and rural boys was 13.89 and 13.81 years, respectively. Compared with that in 2010, the age at spermarche in urban and rural boys was 0.08 and 0.27 years earlier, respectively. After adjusting for age, province and urban/rural areas, compared with normal weight, spermarche was negatively associated with wasting and positively associated with overweight and obesity, with OR (95%CI) about 0.73 (0.67-0.80), 1.09 (1.02-1.17) and 1.09 (1.01-1.18), respectively. Conclusion: The age of spermarche generally shows an advanced trend among Chinese Han boys and is associated with nutritional status.

[Epidemiology and prediction of overweight and obesity among children and adolescents aged 7-18 years in China from 1985 to 2019].

Objective: To analyze and predict the epidemic trend of overweight and obesity among children and adolescents aged 7-18 years in China from 1985 to 2019. Methods: Data were collected from the Chinese National Survey on Students Constitution and Health in 1985, 1995, 2000, 2005, 2010, 2014, and 2019 with the sample size of 409 945, 204 931, 209 209, 234 420, 215 317, 214 353, and 212 711, respectively. Overweight and obesity were evaluated according to the "classification standard of the weight index value of overweight and obesity screening for Chinese school-age children and adolescents" of the Working Group on Obesity in China (WGOC). The detection rate and average annual growth rate of overweight and obesity, and single obesity among children and adolescents aged 7-18 years were calculated, and ArcGis10.6 software was used to analyze the difference in the prevalence of overweight and obesity among children and adolescents in different regions in 2019. Polynomial regression function was used to fit the prevalence and average annual growth rate of overweight and obesity, and single obesity among children and adolescents from 1985 to 2019, and to predict the prevalence of overweight and obesity and single obesity among children and adolescents in China. Results: In 2019, the total prevalence of overweight and obesity among children and adolescents aged 7-18 years in China was 23.4%, and the prevalence of single obesity was 9.6%. The prevalence of overweight and obesity among urban children and adolescents was higher than that in rural areas (25.4% vs. 21.5%), and the prevalence in boys was higher than that in girls (28.4% vs. 18.4%) (both P values<0.001). In 2019, there was a large regional disparity in the prevalence of overweight and obesity in different provinces, with the lowest in Guangdong (12.2%) and the highest in Shandong (38.9%), and the high epidemic areas were mainly concentrated in North China and Northeast China. From 1985 to 2019, the prevalence of overweight and obesity among children and adolescents aged 7-18 years in China increased from 1.2% to 23.4%, with an increase of 18.1 times, while the prevalence of obesity alone increased from 0.1% to 9.6%, with an increase of 75.6 times. The prevalence of overweight and obesity in urban boys, urban girls, rural boys and rural girls increased from 1.3%, 1.5%, 0.5%, and 1.6% in 1985 to 31.2%, 19.4%, 25.6%, and 17.4% in 2019, with an increase of 22.3, 11.7, 54.2, and 10.1 times, respectively. According to the prediction model, the prevalence of overweight and obesity among children and adolescents aged 7-18 years in China will increase from 23.4% in 2019 to 32.7% in 2030, and the prevalence of obesity alone will increase from 9.6% in 2019 to 15.1% in 2030. The growth of rural children and adolescents is obvious. By 2025, the prevalence of overweight and obesity among rural children and adolescents in China will comprehensively exceed that of urban, and there will be an "urban-rural reversal" phenomenon. At the same time, the prevalence of children's obesity in China's low, medium and high epidemic areas will also continue to increase. By 2035, the prevalence of overweight and obesity among children and adolescents in medium epidemic areas will exceed that in high epidemic areas, and there will be a "provincial reversal" phenomenon. Conclusion: From 1985 to 2019, the overweight and obesity of children and adolescents in China will continue to grow rapidly with large regional differences.

[Prevalence trend of malnutrition among Chinese Han children and adolescents aged 7-18 years from 2010 to 2019].

Objective: To analyze the prevalence trend of malnutrition among Chinese Han children and adolescents aged 7-18 years from 2010 to 2019. Methods: Based on the data from the Chinese National Surveys on Students' Constitution and Health in 2010, 2014 and 2019, about 215 102, 214 268 and 212 713 Han students aged 7-18 years were included in this study. According to the National Screening Standard for Malnutrition of School-age Children and Adolescents, the detection rate of malnutrition among Chinese Han children and adolescents aged 7-18 was calculated, and the prevalence trend of malnutrition from 2010 to 2019 was analyzed. Results: In 2019, the detection rate of malnutrition among Chinese Han students aged 7-18 years was 8.64% (18 381/212 713), of which the rate of growth retardation, moderate-to-severe wasting and mild wasting was 0.50% (1 062/212 713), 3.25% (6 914/212 713) and 4.89% (10 405/212 713), respectively. In 2019, the detection rate of malnutrition in these boys was higher than that of girls (9.97% vs. 7.31%), and the detection rate in rural areas was higher than that in cities (9.30% vs. 7.98%). The detection rates were 9.74% (5 252/53 916), 8.17% (4 408/53 937), 7.29% (3 885/53 310), and 9.38% (4 836/51 550) in 7-9, 10-12, 13-15, and 16-18 years groups, and 8.14% (6 563/80 618), 7.61% (4 237/55 694) and 9.92% (7 581/76 401) in the eastern, central, and western regions. Malnutrition among students in China was mainly caused by mild wasting, and the detection rate of growth retardation accounted for only 5.78% (1 062/18 381). Malnutrition was mostly concentrated in the southwest region, and the rate was relatively low in eastern provinces. In three surveys from 2010 to 2019, the detection rate of malnutrition among Han students aged 7-18 in China decreased gradually, and the differences were statistically significant (P<0.05). Among them, the detection rates in western rural areas decreased significantly, as well as the gap between urban and rural areas. Compared with that in 2014, the detection rate of malnutrition in Shandong, Hunan, Qinghai and Hainan provinces in 2019 decreased significantly (P<0.05). Conclusion: In 2019, the malnutrition of Chinese children and adolescents aged 7-18 years is dominated by wasting malnutrition. The detection rate shows a downward trend from 2010 to 2019, with regional differences.

[Trend of the detection rate of myopia among Chinese Han children and adolescents aged 7-18 years from 2010 to 2019].

Objective: To analyze the trend of the detection rate of myopia among Chinese Han children and adolescents aged 7-18 years from 2010 to 2019. Methods: Data from the Chinese National Survey on Students' Constitution and Health in 2010, 2014 and 2019 were used, and about 213 833, 212 742 and 209 942 Han students aged 7-18 years were included in this study. The χ² test was used to compare the differences in the prevalence of myopia among the subgroups in the survey year, and logistic regression was used to compare the differences in the prevalence of myopia between different years. A curve-fitting method was used to obtain the growth rate of myopia among Han Chinese students from 2010 to 2019, and the differences in the change of myopia between different age groups were analyzed. Results: In 2019, the overall detection rate of myopia among Chinese Han children and adolescents aged 7-18 was 60.1%. The detection rate of urban students (62.7%) was higher than that of rural students (57.4%) and the detection rate of girls (63.5%) was higher than that of boys (56.7%). In 2019, the regional disparities were large in the detection rate of myopia in various provinces, with the lowest in Guizhou (49.6%) and the highest in Zhejiang (71.3%). The detection rate of myopia showed an upward trend from 2010 to 2019, from 55.5% in 2010 to 57.1% in 2014, and finally to 60.1% in 2019. The gap in the detection rate of myopia between urban and rural children and adolescents gradually shrank. The average annual growth rate of myopia detection rate from 2014 to 2019 was 0.6 percentage points per year, higher than that from 2010 to 2014 about 0.4 percentage points per year. The peak age of the growth rate of myopia detection rate decreased from 12 years in 2010 to 10 years in 2014, and finally to 7 years in 2019. Conclusions: The detection rate of myopia among Chinese Han children and adolescents is still at a high level, and the peak age of the growth rate of myopia detection rate continues to advance.

[Trend of age of menarche among Chinese Han girls aged 9 to 18 years from 2010 to 2019].

Objective: To analyze the trends of the age of menarche among Chinese Han girls aged 9 to 18 years from 2010 to 2019. Methods: Data were extracted from the Chinese National Surveys on Students' Constitution and Health in 2010, 2014 and 2019. A total of 253 037 Han girls aged 9 to 18 years with complete data on menarche were selected in this study. They were asked one-on-one about their menstrual status, age and residence information. The median age of menarche was estimated by probability regression. U tests were used to compare the difference in median age at menarche in different years. Results: The median age at menarche (95%CI) among Chinese Han girls was 12.47 (12.09-12.83) years in 2010, 12.17 (11.95-12.38) years in 2014 and 12.05 (10.82-13.08) years in 2019, respectively. Compared with that in 2010, the median age at menarche in 2019 decreased by 0.42 years (U=-77.27, P<0.001). The annual average changes were -0.076 years from 2010 to 2014 (U=-57.19, P<0.001) and -0.023 years from 2014 to 2019 (U=-21.41, P<0.001), respectively. The average annual changes in urban areas in the periods of 2010 to 2014 and 2014 to 2019 were -0.071 years and 0.006 years, respectively, while those in rural areas were -0.082 years and -0.053 years, respectively. The average annual changes in the regions of north, northeast, east, south central, southwest and northwest were -0.064, -0.099, -0.091, -0.080, -0.096 and -0.041 years in the period of 2010 to 2014 and 0.001, -0.040, -0.002, -0.005, -0.043 and -0.081 years in the period of 2014 to 2019. Conclusion: The age of menarche among Chinese Han girls aged 9 to 18 years shows an advanced trend from 2010 to 2019, and the trends in urban and rural areas and different regions have different characteristics.