[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.

[A study on the burden of myocarditis in China in 1990 and 2019].

Objective: To investigate Chinese myocarditis burden and trends in 1990 and 2019. Methods: Based on the Global Burden of Disease (GBD) 2019 data, the number of patients, the number of new cases, the number of deaths, the disability-adjusted life years (DALYs), as well as the morbidity, mortality, DALYs rate and their age-standardized rates were used to analyze the trend and the burden of myocarditis in the Chinese population in 1990 and 2019. Results: In 2019, the number of patients, the number of new cases and the number of deaths with myocarditis in China were 234 900, 275 100 and 13 100 respectively, increasing by 85.62%, 47.51% and 50.22% compared with 1990. The age-standardized incidence and mortality were 16.94/100 000 and 0.92/100 000, respectively. Compared with 1990, the age-standardized incidence in 2019 decreased by 6.06%, and the mortality decreased by 16.04% respectively. The age-standardized incidence and mortality of Chinese male patients with myocarditis were higher than that of female. Compared with 1990, the age group with the largest incidence and mortality of myocarditis in China in 2019 all shifted to the elder group. And, DALYs and age-normalized DALYs due to myocarditis in China showed a decreasing trend in 2019, from 458 600 and 42.51/100 000 in 1990 to 341 300 and 25.39/100 000 in 2019, respectively. The rate of DALYs and age-standardized DALYs in male patients was always higher than female. Conclusions: Compared with 1990, the overall burden of myocarditis in China showed a downward trend in 2019, and the burden of myocarditis in male patients was higher than female. More attention should be paid to the burden of myocarditis in Chinese elderly population.

[The disease burden of degenerative mitral valve disease in the Chinese population from 1990 to 2019].

Objective: To explore the trend of disease burden of degenerative mitral valve disease (DMVD) in the Chinese population from 1990 to 2019. Methods: Based on the 2019 Global Burden of Disease database (GBD 2019), the number of patients, the number of new cases, the number of deaths, the disability-adjusted life years (DALY) as well as the prevalence, incidence and death rate, DALY rate and their age-standardized rates were used to analyze the trend of the burden of DMVD in the Chinese population from 1990 to 2019. Results: In 2019, the number of patients, the number of new cases, and the number of deaths with DMVD in China were 461.2, 27.0 and 0.129 ten thousand, respectively, which increased by 209.0%, 199.1% and 13.2% when compared with 1990. In 2019, the age-standardized prevalence, incidence and death rate were 228.1/100 000, 12.7/100 000 and 0.075/100 000, respectively. Compared with 1990, the change of the age-standardized prevalence, incidence and death rate were 32.6%, 42.8% and -54.1%, respectively. In addition, the 2019 data also showed that the age-standardized prevalence and incidence were higher in females than in males (the age-standardized prevalence was 190.1 (181.5-198.9)/100 000 for males and 262.0 (250.3-273.9)/100 000 for females); the age-standardized incidence was 10.5 (10.0-11.0)/100 000 for males and 14.9 (14.3-15.6)/100 000 for females. The age group with the largest number of DMVD patients was 65 to 69 years old, and the highest incidence was 60 to 64 years old. From 1990 to 2019, DALY caused by DMVD showed an upward trend in China, from 46 439 person-years in 1990 to 69 402 person-years in 2019, with an increase of 49.4%. While the age-standardized DALY rate continued to decline, from 5.5/100 000 in 1990 to 3.8/100 000 in 2019, with a drop of 30.8%. The DALY and the age-standardized DALY rate of females were always higher than that of males in different years. Conclusion: From 1990 to 2019, DALY and the age-standardized prevalence and incidence of DMVD in China shows an increasing trend, and the disease burden caused by DMVD is severe in China.

[Regional inequality of height among Chinese Han students aged 7 to 18 years from 1985 to 2014].

Objective: To analyze the regional inequality of height among Chinese Han students aged 7 to 18 years from 1985 to 2014. Methods: The Chinese Han students aged 7 to 18 years with complete basic information and height data from 30 mainland provinces (excluding Hong Kong, Macao, Taiwan and Tibet in China) were extracted as participants from 6 successive cross-sectional surveys of the Chinese National Survey on Student's Constitution and Health (CNSSCH). After excluding extreme and illogical cases, a total of 1 495 182 students were included in the analysis. The data of gross domestic product (GDP) per capita of each province at each survey year were collected from the website of National Bureau of statistics of China. Mann-Kendall trend test was used to analyze the trend of mean height across years. Weighted linear regression model was used to analyze the association between mean height of students aged 7 to18 years and GDP per capita at provincial level. Height difference, height ratio, slope index of inequality (SII) and relative index of inequality (RII) were used to measure the height inequality by gender and age groups. Results: The mean height of Chinese Han students aged 7 to 18 years increased from 144.9 cm in 1985 to 151.8 cm in 2014 (P<0.05). The height difference between urban and rural students in all age groups was reducing (P<0.05). The height difference between urban and rural boys aged 13 to 15 years decreased from 5.3 cm in 1985 to 2.5 cm in 2014, and the difference between urban and rural girls aged 7 to 12 years decreased from 4.6 cm in 1985 to 2.4 cm in 2014. The mean height of students aged 7 to 18 years was positively associated with GDP per capita in all survey years for both genders (P<0.001). Taking Shanghai and Guizhou as the representatives of economically developed and underdeveloped provinces, from 1985 to 2014, the height differences between two provinces were 6.8-9.2 cm, 8.0-12.4 cm and 6.3-8.8 cm for boys aged 7 to 12 years, 13 to 15 years and 16 to 18 years, respectively, and the height ratios were stable at 1.05-1.07, 1.05-1.08 and 1.04-1.05 respectively. From 1985 to 2014, the SII of mean height for boys in three age groups were 4.4-6.2, 4.9-6.7 and 2.5-4.7, respectively. The RII of mean height of boys in three age groups were 1.03-1.05, 1.03-1.04 and 1.01-1.03, respectively. In the same period, the SII of mean height for girls in three age groups were 4.2-6.2, 2.8-4.5 and 2.5-3.9, and the RII were 1.03-1.05, 1.02-1.03 and 1.02, respectively. Conclusion: From 1985 to 2014, the urban-rural inequality of height development among Chinese Han students aged 7 to 18 years was narrowing, but the socio-economic inequality of height persisted and remained at a relatively stable level.

[Subnational inequalities of early marriage and fertility among Chinese females from 1990 to 2010].

OBJECTIVE: To analyze the inequality of early marriage and adolescent fertility with respect to local economic development among Chinese females aged 15-19 years from 1990 to 2010. METHODS: Aggregated data were extracted from the Chinese National Census from 1990 to 2010. We calculated the ever-married rate and fertility rate of female adolescents aged 15-19 years. Using gross domestic product (GDP) per capita as an indicator for socio-economic status of a province, we calculated the slope index of inequality (SII) and the concentration index (CI) to analyze the subnational inequalities of early marriage and adolescent fertility. Weighted linear regression models were also established to assess the associations between GDP per capita and the ever-married rate/fertility rate. RESULTS: The ever-married rate for Chinese female adolescents aged 15-19 years decreased from 4.7% in 1990 to 1.2% in 2000, and rebounded to 2.1% in 2010. From 1990 to 2000, the fertility rate decreased from 22.0 per 1 000 to 6.0 per 1 000, and further decreased to 5.9 per 1 000 in 2010. In 1990, the socio-economic inequalities of the ever-married rate and fertility rate for female adolescents aged 15-19 years were not statistically significant (P for SII or CI>0.05). The values of SII revealed that, in 2000 and 2010, female adolescents with the lowest GDP per capita had an ever-married rate 2.4% (95%CI: 0.4-4.4) and 2.3% (95%CI: 0.3-4.2) higher than those with the highest GDP per capita, respectively. In the meantime, in 2000 and 2010, female adolescents with the lowest GDP per capita had a fertility rate 12.9 per 1 000 (95%CI: 5.4-20.5) and 9.3 per 1 000 (95%CI: 4.6-14.0) higher than those with the highest, respectively. In 2000 and 2010, the CIs for marriage were -0.32 (P=0.02) and -0.17 (P=0.03), respectively, and the CIs for childbirth were -0.37 (P<0.01) and -0.26 (P<0.01), respectively. In 2000, the ever-married rate and the fertility rate were estimated to increase by 1.4% (95%CI: 0.1-2.7) and 7.9 per 1 000 (95%CI: 2.9-12.8) with 100% increase in GDP per capita, respectively; in 2010, the numbers were 1.5% (95%CI: 0.1-2.9) and 6.7 per 1 000 (95%CI: 3.2-10.1), respectively. CONCLUSION: Subnational socio-economic inequality of early marriage and adolescent fertility existed in 2000 and 2010. Female adolescents residing in less-developed areas were more likely to engage in early marriage and childbirth. Reducing income inequality and increasing education investment for poverty-stricken areas seem to be effective measures to reduce this inequality.

[Secular trends and geographic disparities of all-cause mortality among Chinese adolescents aged 10-24 years, between 1953 and 2010].

Objective: To analyze the secular trends and geographic disparities of all-cause mortality among Chinese adolescents aged 10-24 years over the period of 1953-2010. Methods: Data were extracted from the Chinese National Census in 1953-2010. We calculated the all-cause mortality and annualized rates of the changes. Using the provincial gross domestic product (GDP) per capita as an indicator of regional socio-economic development level, we calculated the Wagstaff normal concentration indices for adolescent mortality. Results: Over the period of 1953-2010, the general patterns of Chinese adolescent mortality appeared higher in males than those in females, higher in the 20-24-year-old than those in the 15-19 year-old and in the 10-14 year-old groups, higher in adolescents from the western than those in the eastern regions. The mortality of adolescents decreased from 554.6/100 000 in 1953-1964 to 55.7/100 000 in 2010 in males and decreased from 488.4/100 000 to 26.7/100 000 in females, respectively. The percentage of decrease for females (94.5%) was higher than that for males (90.0%). In 1981-2010, the highest annualized rate of decline for males was seen in Beijing (4.4%), with the lowest seen in Qinghai (0.1%). For girls, Hubei showed the highest annualized rate of decline (6.4%) while Qinghai the lowest (0.8%). Provinces that with higher mortality tended to have lower annualized rate of decline. The concentration indices for boys were -0.07 (95%CI: -0.11- -0.03), -0.13 (95%CI: -0.18- -0.08), and -0.16 (95%CI: -0.22- -0.10) in 1990, 2000, and 2010, respectively, and were -0.07 (95%CI: -0.13- -0.02), -0.18 (95%CI: -0.24- -0.12), and -0.18 (95%CI: -0.26- -0.09) respectively in girls. The indices among 1990, 2000, and 2010 did not show statistically significantly differences, both for boys and girls (P>0.05). Conclusions: Over the half century, the mortality of Chinese adolescents showed dramatic decreasing trend. However, in terms of death rates, gender and geographic disparities were consistently seen in the adolescents.

[Analysis on the urban-rural disparity of childhood stunting and its association with economic growth among Chinese Han students aged 7-18 years old].

Objective: To analyze the urban-rural disparity of childhood stunting and its association with subnational economic growth among Chinese Han students aged 7-18 years. Methods: We used the data from 2014 Chinese National Survey on Students' Constitution and Health. 213 940 Chinese Han students aged 7-18 years with complete height records were included in this study. Stunting was defined according to the Screening Criteria of Malnutrition for School-age Children and Adolescents(2014 version, in Chinese). We divided students into two groups (economically developed and underdeveloped areas) according to the provincial GDP per capita. Spearman correlation coefficient was used to explore the association between the difference of urban-rural stunting prevalence and the provincial GDP per capita. Logistic regression models were established to assess the risk of stunting in rural children compared with urban children. Results: Among 213 940 students, 107 033 (50.0%) were from urban areas. The average height of 7-18 years old and 18 years old [(152.9±15.7) and (166.1±8.7) cm] of urban students were both higher than those of rural students [(150.7±16.0) and (165.1±8.6) cm] (P<0.001). The stunting prevalence of Chinese urban students (0.4%) was statistically significant lower than that of rural students (1.1%) (P<0.001), which was consistent in all age groups (P<0.05). The urban-rural disparity was found in 60% (18/30) of Chinese provinces. The difference of urban-rural stunting prevalence was negatively associated with provincial GDP per capita (r=-0.62, P<0.001). In economically underdeveloped areas, the risk of stunting for rural students aged 7-9 years was 4.69 (95%CI: 2.93-7.52) times that for urban children, while for students aged 10-18 years, the odds ratio was 2.44 (95%CI: 2.02-2.96). In economically developed areas, the risk of stunting for rural students aged 7-9 years was 5.43 (95%CI: 3.67-8.03) times that for urban children, while for students aged 10-18 years, the odds ratio was 2.15 (95%CI: 1.85-2.49). Conclusions: The urban-rural disparity of childhood stunting existed in most places in China. The difference of growth retardation between urban and rural areas was related to regional economic development.

[Assessment on Application of 24 Y-STR Loci in Forensic Science].

OBJECTIVES: To select a Y-STR marker system with strong haplotype identification ability, appropriate mutation rate and high compatibility and to assess its forensic application. METHODS: The 24 Y-STR loci were tested by self-built fluorescent multiplex system, and the forensic assessment was conducted by 139 pairs of father-son samples collected in Jinan, Shandong province. RESULTS: Totally 176 alleles were identified among the 24 Y-STR loci in the sample of 139 unrelated individuals labeled with father, and the gene diversity （GD） distributed between 0.083 7 （DYS645）-0.966 9 （DYS385a/b）. According to the 24 Y-STR loci, 139 different haplotypes were detected from 139 unrelated male individuals labeled with father in Han population of Shandong province and with no shared haplotype observed. The overall haplotype diversity （HD） was 1 and the discrimination capacity （DC） was 1. A total of 5 one-step mutations events were observed among the 24 Y-STR loci in 139 pairs of father-son. The average mutation rate was 0.001 5 [95% CI （0.000 5, 0.003 5）]. CONCLUSIONS: The system of 24 Y-STR loci shows a strong individual recognition ability and low mutation rate in the population in Jinan, Shandong province, and it has good application value in forensic science.