Changing trends in the global, regional, and national burden of iodine deficiency among adolescents and young adults: population-based study.

Iodine is a micronutrient required for the production of thyroid hormones, which regulate metabolism, growth, and neurodevelopment. Iodine deficiency among adolescents and young adults is a major global health issue. We analyzed data from the Global Burden of Disease 2019 database to calculate the prevalence, incidence, and disability-adjusted life-year (DALY) rates of iodine deficiency among adolescents and young adults. We explored the specific year with the most substantial changes in the trends of iodine deficiency among adolescents with annual percentage change (APC) by Joinpoint Regression analysis. Descriptive analyses were conducted to characterize the iodine deficiency burden according to age, sex, location, and sociodemographic index (SDI) quintiles. All measures are listed with 95% uncertainty intervals (UIs), and all rates are reported per 100,000 individuals. From 1990 to 2019, the iodine deficiency prevalence rate among adolescents decreased from 3082.43 (95% uncertainty interval [UI], 2473.01-3855.86) to 2190.84 (95% [UI], 1729.18-2776.16) per 100,000 population, with an AAPC of -1.15 (95% confidence interval [CI], -1.29 to -1.02). Regarding the SDI in 2019, the highest prevalence and DALY rates of iodine deficiency were reported in low-SDI countries. In 1990, Southeast Asia had the highest prevalence and DALYs rates for iodine deficiency among adolescents, while in 2019, Africa had the highest prevalence rate (3330.12). CONCLUSION: Globally, the iodine deficiency burden among adolescents has substantially decreased since 1990; however, low-SDI countries still bear a great burden. Implementation measures and monitoring systems should be strengthened to reduce the iodine deficiency burden, especially among adolescents. WHAT IS KNOWN: • Iodine deficiency can cause severe or irreversible developmental disorders, particularly in adolescents and young adults. • Universal Salt Iodization was implemented for ensuring appropriate iodine intake. WHAT IS NEW: • We found substantial declines in the prevalence rates of iodine deficiency among adolescents during the past three decades. Globally, the disability-adjusted life-year rate of iodine deficiency among adolescents decreased from 56.17 in 1990 to 35.38 in 2019. • Iodine deficiency among adolescents in low- sociodemographic index countries still bear a great burden.

Development and validation of a risk assessment model for prediabetes in China national diabetes survey.

BACKGROUND: Prediabetes risk assessment models derived from large sample sizes are scarce. AIM: To establish a robust assessment model for prediabetes and to validate the model in different populations. METHODS: The China National Diabetes and Metabolic Disorders Study (CNDMDS) collected information from 47325 participants aged at least 20 years across China from 2007 to 2008. The Thyroid Disorders, Iodine Status and Diabetes Epidemiological Survey (TIDE) study collected data from 66108 participants aged at least 18 years across China from 2015 to 2017. A logistic model with stepwise selection was performed to identify significant risk factors for prediabetes and was internally validated by bootstrapping in the CNDMDS. External validations were performed in diverse populations, including populations of Hispanic (Mexican American, other Hispanic) and non-Hispanic (White, Black and Asian) participants in the National Health and Nutrition Examination Survey (NHANES) in the United States and 66108 participants in the TIDE study in China. C statistics and calibration plots were adopted to evaluate the model's discrimination and calibration performance. RESULTS: A set of easily measured indicators (age, education, family history of diabetes, waist circumference, body mass index, and systolic blood pressure) were selected as significant risk factors. A risk assessment model was established for prediabetes with a C statistic of 0.6998 (95%CI: 0.6933 to 0.7063) and a calibration slope of 1.0002. When externally validated in the NHANES and TIDE studies, the model showed increased C statistics in Mexican American, other Hispanic, Non-Hispanic Black, Asian and Chinese populations but a slightly decreased C statistic in non-Hispanic White individuals. Applying the risk assessment model to the TIDE population, we obtained a C statistic of 0.7308 (95%CI: 0.7260 to 0.7357) and a calibration slope of 1.1137. A risk score was derived to assess prediabetes. Individuals with scores ≥ 7 points were at high risk of prediabetes, with a sensitivity of 60.19% and specificity of 67.59%. CONCLUSION: An easy-to-use assessment model for prediabetes was established and was internally and externally validated in different populations. The model had a satisfactory performance and could screen individuals with a high risk of prediabetes.

Direct medical costs for patients with type 2 diabetes in 16 tertiary hospitals in urban China: A multicenter prospective cohort study.

AIMS/INTRODUCTION: To investigate the direct medical costs for patients with type 2 diabetes in China and to examine the influencing factors. MATERIALS AND METHODS: In the present multicenter study, 1,070 patients with type 2 diabetes from 16 tertiary hospitals in 14 major cities of China were enrolled. Patient data and direct medical costs were collected during a follow-up period of 6 months at intervals of 1 month. The log-transformed direct medical costs were fitted by a generalized estimation equation to indicator variables for demographics, metabolic control, treatments, complications and comorbidities. RESULTS: Data of 871 participants were included in the analysis. The mean annual total direct medical costs and outpatient medical costs were $1,990.20 and $1,687.20 respectively. The average costs per inpatient per admission were $2,127.10. The share of out-of-pocket for total medical costs, outpatient costs and cost per inpatient per admission were 45.4, 46.3 and 26.0% respectively. Independent determinants of total medical costs were diabetes duration, dyslipidemia and diabetic complications, such as neuropathy and nephropathy, as well as diabetes treatment, such as the use of glucagon-like peptide-1 receptor agonists. Costs showed prominent variation across centers. CONCLUSIONS: Diabetes is imposing a growing economic burden in patients with type 2 diabetes in China. Diabetes-related complications and comorbidities have a great impact on the medical costs. As different health policies, economic development and regional health inequalities also have an important influence on the direct medical cost, healthcare reform needs to optimize resource allocation in health service delivery systems, and provide more equitable and affordable healthcare.

Effect of Iodine Nutrition on Pregnancy Outcomes in an Iodine-Sufficient Area in China.

Many studies focused on the association between thyroid disease and pregnancy outcomes. The present study explored the effect of iodine nutrition during the first trimester on pregnancy outcomes. One thousand five hundred sixty-nine pregnant, euthyroid women at ≤12 weeks of gestation in an iodine-sufficient area in China were recruited. According to the World Health Organization (WHO) criteria for iodine nutrition during pregnancy, participants were divided into four groups: adequate iodine (median urinary iodine concentration (UIC), 150-249 µg/L), mild deficiency (UIC, 100-150 µg/L), moderate and severe deficiency (UIC, <100 µg/L), and more than adequate and excessive (UIC, ≥250 µg/L) groups. Pregnancy outcomes, including abortion, gestational hypertension, pre-eclampsia, gestational diabetes mellitus (GDM), placenta previa, placental abruption, preterm labor, low birth weight infants, macrosomia, breech presentation, and cord entanglement, were obtained during follow-up. The results showed that there was no significant difference in general characteristics, including age, body mass index, abdominal circumference, systolic blood pressure, diastolic blood pressure, heart rate, smoking rate, and drinking rate, among the four groups. In the more than adequate and excessive group, thyroid-stimulating hormone (TSH) was greater and free thyroxine (FT4) was lower than any other groups but still within normal range. The thyroglobulin (Tg) level was greater in the moderate and severe deficiency group. The incidence of GDM was significantly greater in women with mild iodine deficiency than in women with adequate iodine nutriture (18.38 vs. 13.70%, p < 0.05). Compared with the adequate group, incidence of macrosomia was significantly greater in the more than adequate and excessive group (12.42 vs. 9.79%, p < 0.05). Mild iodine deficiency was an independent risk factor for GDM (odds ratio = 1.566, 95% confidence interval = 1.060-2.313, p = 0.024); more than adequate and excessive iodine was an independent risk factor for macrosomia (OR = 1.917, CI = 1.128-3.256, p = 0.016). In summary, during 1st trimester, both mild iodine deficiency and excessive iodine intake had adverse impacts on pregnancy outcomes in an iodine-sufficient area.

The Urine Iodine to Creatinine as an Optimal Index of Iodine During Pregnancy in an Iodine Adequate Area in China.

CONTEXT: Iodine nutrition is a global event, especially for pregnant women. OBJECTIVE: To develop applicable index of iodine intake for population during pregnancy. DESIGN, SETTING, AND PARTICIPANTS: From 2012 to 2014, pregnant women at less than 8 weeks of gestation (n = 222) and reproductive-age women (n = 827) participated in this study. The pregnant women were evaluated at follow-up visits at 8, 12, 16, 20, 28, and 36 weeks of gestation and 3 and 6 months postpartum. MAIN OUTCOME MEASURES: Twenty-four-hour urine samples were collected at weeks 8 of gestation. Urine iodine (UI) and creatinine (Cr) and serum thyroglobulin were measured in all of the subjects. Circulatory iodine was measured using inductively coupled plasma-mass spectrometry at 8, 20, and 36 weeks of gestation and 6 months postpartum. RESULTS: The median UI concentration decreased from 183.6 to 104.2 µg/L during pregnancy. The serum iodine (SI) changes were similar to the UI to creatinine ratio (UI/Cr). The SI level was lowest at the eighth week of gestation (60.5 µg/L), which rose significantly until 20 weeks (106.5 µg/L) and then began to decline (36 wk, 84.7 µg/L). The 24-hour UI excretion measurement was regarded as the gold standard. The area under the receiver-operating characteristic curve for UI/Cr was 0.92 for iodine deficiency diagnoses and 0.78 for SI. The area for SI was 0.82 for excessive iodine diagnoses and 0.75 for UI/Cr. The areas under these curves were significantly different (P < .001). The areas under the receiver-operating characteristic curve for UI were 0.61 (P = .11) and 0.65 (P = .08) for iodine deficiency and excessive iodine diagnoses, respectively. Additionally, for thyroglobulin, these values were 0.54 (P = .53) and 0.53 (P = .74), respectively. CONCLUSIONS: Iodine intake, as assessed by spot UI concentration in pregnant women, is inaccurate and increases the prevalence of iodine deficiency. The UI/Cr better reflects the 24-hour iodine excretion and circulating iodine levels during pregnancy and the postpartum period.

Assessment of thyroid function during first-trimester pregnancy: what is the rational upper limit of serum TSH during the first trimester in Chinese pregnant women?

CONTEXT: Guidelines of the American Thyroid Association (ATA) proposed that the upper limit of the TSH reference range should be 2.5 mIU/L in first trimester, but the reported ranges in China are significantly higher. OBJECTIVE: Our objective was to establish a rational reference range of serum TSH for diagnosis of subclinical hypothyroidism in the first trimester of pregnant women in China. DESIGN: We screened 4800 pregnant women in the first trimester and 2000 women who planned to become pregnant and evaluated 535 pregnant women in follow-up visits during the second and third trimester. RESULTS: Median concentrations of serum TSH decreased significantly from the seventh week of gestation. The median of TSH from 4 to 6 weeks was significantly higher than from 7 to 12 weeks (2.15 [0.56-5.31] mIU/L vs 1.47 [0.10-4.34] mIU/L, P<.001); however, there was no significant difference compared with nonpregnant women (2.07 [0.69-5.64] mIU/L; P=.784). The median of free T4 was not significantly altered in the first trimester. The prevalence of subclinical hypothyroidism in the 4800 pregnant women was 27.8% on the diagnostic criteria of TSH>2.5 mIU/L and 4.0% using the reference interval derived by our laboratory (0.14-4.87 mIU/L).Additionally, of 118 pregnant women who had serum TSH>2.5 mIU/L in the first trimester, only 30.0% and 20.3% of them at the 20th and 30th week of gestation had TSH>3.0 mIU/L. CONCLUSIONS: The reference range for nonpregnant women can be used for the assessment of pregnant women at 4 to 6 weeks of gestation. The upper limit of serum TSH in the first trimester was much higher than 2.5 mIU/L in Chinese pregnant women.

Prevalence and associated factors of microalbuminuria in Chinese individuals without diabetes: cross-sectional study.

OBJECTIVE: To investigate the prevalence of microalbuminuria (MAU) among Chinese individuals without diabetes and the relationship between MAU and metabolic factors, individual socioeconomic status (SES), and regional economic development level. DESIGN: Cross-sectional study of prevalence of MAU. SETTING: 152 urban street districts and 112 rural villages from northeast, north, east, south central, northwest and southwest China. PARTICIPANTS: 46 239 participants were recruited using a multistage stratified sampling design from 2007 to 2008. A total of 41 290 participants without diabetes determined by oral glucose tolerance test were included in the present study. Urine albumin/creatinine ratio results of 35 430 individuals were available. PRIMARY AND SECONDARY OUTCOME MEASURES: Positive detection of MAU was determined using an ACR of 22.1-299.9 mg/g in men 30.9-299.9 mg/g in women. RESULTS: The prevalence of MAU in men was 22.4% and 24.5% in women. In developed, intermediate-developed and under-developed areas, the prevalence of MAU in men was 20.7%, 21.9% and 32.5%, respectively; in women the prevalence was 19.6%, 26.0% and 29.5%, respectively. The prevalence of MAU increased as the number of metabolic disorders present increased, and as the number of lower SES components increased (farmer, below university education level and low income). Prevalence of MAU in developed and intermediate developed areas had adjusted risk ratios of 0.52 (95% CI 0.42 to 0.60) and 0.65 (95% CI 0.57 to 0.76), respectively. Multivariate logistic analyses demonstrated MAU was strongly associated with older age, high-blood pressure, higher blood glucose low education level, low occupational level and residence in under-developed region. CONCLUSIONS: Several factors had independent correlations to MAU in China: older age, metabolic abnormalities, lower SES level and living in economically under-developed areas, which encourage the development of strategies to lower the risk for MAU in these susceptible populations.

Nonlaboratory-based risk assessment algorithm for undiagnosed type 2 diabetes developed on a nation-wide diabetes survey.

OBJECTIVE: To develop a New Chinese Diabetes Risk Score for screening undiagnosed type 2 diabetes in China. RESEARCH DESIGN AND METHODS: Data from the China National Diabetes and Metabolic Disorders Study conducted from June 2007 to May 2008 comprising 16,525 men and 25,284 women aged 20-74 years were analyzed. Undiagnosed type 2 diabetes was detected based on fasting plasma glucose ≥7.0 mmol/L or 2-h plasma glucose ≥11.1 mmol/L in people without a prior history of diabetes. ß-Coefficients derived from a multiple logistic regression model predicting the presence of undiagnosed type 2 diabetes were used to calculate the New Chinese Diabetes Risk Score. The performance of the New Chinese Diabetes Risk Score was externally validated in two studies in Qingdao: one is prospective with follow-up from 2006 to 2009 (validation 1) and another cross-sectional conducted in 2009 (validation 2). RESULTS: The New Chinese Diabetes Risk Score includes age, sex, waist circumference, BMI, systolic blood pressure, and family history of diabetes. The score ranges from 0 to 51. The area under the receiver operating curve of the score for undiagnosed type 2 diabetes was 0.748 (0.739-0.756) in the exploratory population, 0.725 (0.683-0.767) in validation 1, and 0.702 (0.680-0.724) in validation 2. At the optimal cutoff value of 25, the sensitivity and specificity of the score for predicting undiagnosed type 2 diabetes were 92.3 and 35.5%, respectively, in validation 1 and 86.8 and 38.8% in validation 2. CONCLUSIONS: The New Chinese Diabetes Risk Score based on nonlaboratory data appears to be a reliable screening tool to detect undiagnosed type 2 diabetes in Chinese population.

Medical care and payment for diabetes in China: enormous threat and great opportunity.

BACKGROUND: The Diabetes Impact Study followed up a large national population-based screening study to estimate the use of and expenditures for medical care caused by diabetes in China and to ascertain the use and cost of essential basic medicines and care. METHODS: In 2009-10, the study team interviewed 1482 adults with diabetes and 1553 adults with glucose tolerance in the normal range from population-based random samples at 12 sites in China. The response rate was 67%. FINDINGS: After adjusting for age, sex, and urban/rural location, people with diabetes received 1.93 times more days of inpatient treatment, 2.40 times more outpatient visits, and 3.35 times more medications than people with normal glucose tolerance (all p<0.05). Adjusted expenditures for medical care were 3.38 times higher among people with diabetes than among people with normal glucose tolerance (p<0.01, unadjusted 3.97). Persons who were diagnosed with ≥ 10 years prior to the survey paid 3.75 times as much for medical care as those with ≤ 5 years of diagnosed diabetes. Among persons with diabetes, 45.2% took medication to control blood sugar, 21.1% took an antihypertensive medicine, 22.4% took daily aspirin, and 1.8% took a statin. Over the three months before the interview, 46.1% of persons with diabetes recalled seeing a doctor, 48.9% recalled a blood pressure measurement, and 54.5% recalled a blood sugar test. Over the year preceding the interview, 32.1% recalled a retinal screening and 17.9% recalled a foot examination. CONCLUSIONS: In China, health care use and costs were dramatically higher for people with diabetes than for people with normal glucose tolerance and, in relative terms, much higher than in industrialized countries. Low-cost generic medicines that would reduce diabetes expenditures were not fully used.

Serum lipids and lipoproteins in Chinese men and women.

BACKGROUND: Because of rapid change in lifestyle risk factors, cardiovascular disease has become the leading cause of death in China. We sought to estimate the national levels of serum lipids and lipoproteins among the Chinese adult population. METHODS AND RESULTS: We conducted a cross-sectional study in a nationally representative sample of 46 239 adults aged ≥20 years. Fasting serum total, high-density lipoprotein, and low-density lipoprotein cholesterol and triglycerides were measured by standard methods. The age-standardized estimates of total, high-density lipoprotein, and low-density lipoprotein cholesterol and triglycerides were 4.72 (95% confidence interval, 4.70-4.73), 1.30 (1.29-1.30), 2.68 (2.67-2.70), and 1.57 (1.55-1.58) mmol/L, respectively, in the Chinese adult population. In addition, 22.5% (21.8-23.3%) or 220.4 million (212.1-228.8) Chinese adults had borderline high total cholesterol (5.18-6.21 mmol/L), and 9.0% (8.5-9.5%) or 88.1 million (83.4-92.8) had high total cholesterol (≥6.22 mmol/L). The population estimates for borderline high (3.37-4.13 mmol/L), high (4.14-4.91 mmol/L), and very high (≥4.92 mmol/L) low-density lipoprotein cholesterol were 13.9% (13.3-14.5%) or 133.5 million (127.0-140.1), 3.5% (3.3-3.8%) or 33.8 million (31.2-36.5), and 3.0% (2.8-3.3%) or 29.0 million (26.3-31.8) persons, respectively. In addition, 22.3% (21.6-23.1%) or 214.9 million (207.0-222.8) persons had low high-density lipoprotein cholesterol (<1.04 mmol/L). The awareness, treatment, and control of borderline high or high total cholesterol were 11.0%, 5.1%, and 2.8%, respectively, in the Chinese adult population. CONCLUSIONS: Serum total and low-density lipoprotein cholesterol levels were high and increasing in the Chinese population. Without effective intervention, atherosclerotic cardiovascular diseases may soar in the near future in China.