Shanxi Institute of Endemic Diseases

This study aims to assess the applicability of the serum iodine (SI) standards proposed by the WHO and other renowned laboratories for the Chinese population. Additionally, it seeks to establish reference intervals (RIs) for SI in Chinese adults and conduct a risk assessment between serum iodine concentration (SIC) and the development of thyroid diseases. This study enrolled 3138 adults aged 18-60 years from six provinces in China. A total of 1794 healthy adults with normal thyroid function were selected to assess the applicability of the international standards and establish China's RI, utilizing five external datasets for validation. Multiple logistic regression analysis was applied to explore the relationship between SIC and thyroid disease. The ratios of adults with normal thyroid function from five provinces whose SI levels fall outside the limits of the international standards are partially greater than 10%. China's RI was 40.11-97.59 µg/L, and the ratios of individuals in the validation datasets outside this RI were all less than 10%. Adults with low SIC levels (< 40.11 µg/L) were at higher risk of hypothyroxinemia (adjusted OR = 4.715, 95% CI = 1.459-15.235), overt hypothyroidism (adjusted OR = 4.719, 95% CI = 1.583-14.067), and autoimmune thyroiditis (adjusted OR = 2.394, 95% CI = 1.410-4.064). Adults with high SIC levels (> 97.59 µg/L) were at a higher risk of overt hyperthyroidism (adjusted OR = 18.170, 95% CI = 5.940-55.577). These international standards are not fully applicable to the Chinese population. We established RIs for SI in Chinese adults to better accommodate the country's specific conditions.

Smoking is a major risk factor for the group 3 PH. NT-proBNP is a biomarker for risk stratification in PH. This study aims to investigate the effects of smoking status and smoking index (SI) on group 3 PH and to evaluate the value of SI and SI combined with NT-proBNP in early diagnosis and prediction of disease severity. Four hundred patients with group 3 PH at the First Hospital of Shanxi Medical University between January 2020 and December 2021 were enrolled and divided into two groups: mild (30 mmHg ≤ pulmonary artery systolic pressure (PASP)≤50 mmHg) and non-mild (PASP >50 mmHg). The effect of smoking on group 3 PH was analyzed using univariate analysis, and logistic analysis was conducted to evaluate the risk of group 3 PH according to smoking status and SI. Spearman correlation coefficient was used to test the correlation between SI and the index of group 3 PH severity. The predictive value of SI was evaluated using a receiver operating characteristic (ROC) curve. Correlation and logistic analyses showed that SI was associated with PH severity. Smoking status (P=0.009) and SI (P=0.039) were independent risk factors for non-mild group 3 PH, and ROC showed that the predictive value of SI (AUC:0.596) for non-mild PH was better than that of the recognized pro-brain natriuretic peptide (NT-proBNP) (AUC:0.586). SI can be used as a single predictive marker. SI and NT-proBNP can be formulated as prediction models for screening non-mild clinical cases (AUC:0.628). SI is a potentially ideal non-invasive predictive marker for group 3 PH. SI and NT-proBNP could be used to develop a prediction model for screening non-mild PH cases. This can greatly improve the predictive specificity of the established PH marker, NT-proBNP.

Hypertension is a major public health concern that strongly influences the quality of life of people worldwide. Keshan disease (KD) is an endemic cardiomyopathy related to low selenium, threatening residents in rural areas of 16 provinces in China. Furthermore, the prevalence of hypertension in the KD-endemic areas has been increasing annually. However, hypertension research associated with KD has only focused on endemic regions, and no studies have compared hypertension prevalence between endemic and non-endemic areas. Therefore, this study investigated the prevalence of hypertension to provide a basis for preventing and controlling hypertension in the KD-endemic areas, even in rural areas. We extracted blood pressure information from cardiomyopathy investigation data from a cross-sectional study of the KD-endemic and non-endemic areas. The hypertension prevalence between the two groups was compared using the Chi-square test or Fisher s exact test. Additionally, Pearson's correlation coefficient was employed to evaluate the relationship between the per capita gross domestic product (GDP) and hypertension prevalence. There was a statistically significant increase of hypertension prevalence in the KD-endemic areas (22.79%, 95% confidence interval [CI]: 22.30-23.27%) over the non-endemic areas (21.55%, 95% CI: 21.09-22.02%). In the KD-endemic areas, more men had hypertension than women (23.90% vs. 21.65%, P < 0.001). Furthermore, the hypertension prevalence was higher in the north than in the south in the KD-endemic areas (27.52% vs. 18.76%, P < 0.001), non-endemic areas (24.86% vs. 18.66%, P < 0.001), and overall (26.17% vs. 18.68%, P < 0.001). Finally, the prevalence of hypertension positively correlated with per capita GDP at province level. The increasing hypertension prevalence is a public health problem in the KD-endemic areas. Healthy diets, such as high consumption of vegetables and seafoods, and foods that are rich in selenium, might help prevent and control hypertension in the KD-endemic areas and other rural areas in China.

It is uncertain how many factors affect urinary iodine concentration. The aim of this study was to determine the effect of consumption of drinking water with high iodine concentration on urinary iodine concentration in pregnant and lactating women, and infants. We included 218 lactating women and their infants and 142 pregnant women in areas with suitable and high water iodine content. Urine, serum, and water iodine concentration were assessed. Breastfeeding women living in areas with high water iodine content had a greater likelihood of iodine sufficiency or iodine excess [odds ratio (P = 0.044, P <0.001)] compared with women living in areas with suitable water iodine content. Older women were less likely to have higher urinary iodine concentration (P = 0.041). Pregnant women who consumed milk > 4 times weekly during pregnancy were more likely to be iodine sufficient (P = 0.028). Living in areas with high water iodine content for > 5years is a risk factor for iodine excess (P <0.001, P = 0.007). There is a probability of higher urinary iodine concentration in pregnant and lactating women and their infants living in areas with high water iodine content. Age had an effect on iodine excess in lactating women. Consumption of milk > 4 times a week during pregnancy and living in an area with high iodine water content for > 5years were associated with iodine sufficiency and iodine excess in pregnant women.

General Secretary Xi Jinping put forward specific requirements for tackling poverty in poverty-stricken areas during his inspection in Shanxi. The endemic diseases in Shanxi have almost all species and widely distributed and seriously harmful. There are still a large number of endemic patients and some areas still need to strengthen the prevention and control measures implemented. The endemic disease has become one of the important factors restricting the economic and social development of endemic area. Based on the profound study and understanding of the spirit of General Secretary Xi Jinping's important speech, combined with the present situation of prevention and control of endemic diseases in Shanxi Province, centering on the targets set in the 13th Five-Year Plan for prevention and control of endemic diseases, the author explores the significance of accurate promotion of prevention and control of endemic diseases for the poverty alleviation, and the strategy of prevention and control of endemic diseases is prospected. Key words: Endemic disease; Accurate prevention and control; Poverty alleviation

Objective To study the nutritional status of pregnant women in Shanxi Province before and after the implementation of the new standards of iodized salt content, provide the basis for scientific supplementation of iodine for pregnant women. Methods According to the method of population proportion sampling, 30 county-level monitoring sites were selected, a primary school was selected from each county (city, district) by the method of simple random sampling and 40 students in 2011 or 50 students in 2014 aged 8-10 years were selected in each school, direct titration was used to detect salt iodine; at the same time, 20 pregnant women were selected from each town where the primary school was located and urinary iodine was determined using arsenic cerium catalytic spectrophotometry (WS/T 107-2006). Results A total of 1 182 and 1 437 salt samples was detected in Shanxi Province in 2011 and 2014, the median of salt iodine was 30.5 and 24.1 mg/kg, respectively, and the difference was statistically significant (H= 567.45, P < 0.01); it was 95.41%, 80.31%, 76.62% of the coverage rate of iodized salt, qualified rate of iodized salt, qualified iodized salt consumption rate in 2014, respectively; which were compared with those in 2011 (97.63%, 97.49%, 95.18%), the differences were statistically significant (χ2= 9.27, 232.40, 166.25, P < 0.01). A total of 440 and 630 urinary samples of pregnant women were tested in 2011 and 2014, the median of urinary iodine was 279.6 and 177.1 μg/L, respectively, iodine nutrition of pregnant women was more than adequate in 2011, and iodine nutrition was suitable in 2014. The difference was statistically significant (H= 153.89, P < 0.01). The proportion of pregnant women's median of urinary iodine less than 150 μg/L in 2014 [41.11% (259/630)] was significantly higher than that in 2011 [8.18% (36/440) , χ2= 140.68, P < 0.01]. The constituent ratio of 250 to 500 μg/L was significantly decreased [23.65% (149/630) vs 54.77% (241/440), χ2= 108.33, P < 0.01). Conclusion It is at a reasonable level of iodine nutrition level of pregnant women in Shanxi after the adjustment of iodized salt content, but the ratio of < 150 μg/L is increasing, which needs to be paid attention to. Key words: Salts; Iodine; Pregnant women; Nutrition