High Hepatitis B Surface Antigen Levels Predict Insignificant Fibrosis in Hepatitis B e Antigen Positive Chronic Hepatitis B

Introduction

There is no data on the relationship between hepatitis B surface antigen (HBsAg) levels and liver fibrosis in hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis B (CHB).

Methods

Serum HBsAg and HBV DNA levels in HBeAg-positive CHB patients with liver biopsies were analyzed. The upper limit of normal (ULN) of alanine aminotransferase (ALT) was 30 and 19 U/L for men and women respectively. Histologic assessment was based on Ishak fibrosis staging for fibrosis and Knodell histologic activity index (HAI) for necroinflammation.

Results

140 patients (65% male, median age 32.7 years) were recruited. 56 (40%) had ALT ≤2×ULN. 72 (51.4%) and 42 (30%) had fibrosis score ≤1 and necroinflammation grading ≤4 respectively. Patients with fibrosis score ≤1, when compared to patients with fibrosis score >1, had significantly higher median HBsAg levels (50,320 and 7,820 IU/mL respectively, p<0.001). Among patients with ALT ≤2×ULN, serum HBsAg levels achieved an area under receiver operating characteristic curve of 0.869 in predicting fibrosis score ≤1. HBsAg levels did not accurately predict necroinflammation score. HBsAg ≥25,000 IU/mL was independently associated with fibrosis score ≤1 (p = 0.025, odds ratio 9.042).Using this cut-off HBsAg level in patients with ALT ≤2×ULN, positive and negative predictive values for predicting fibrosis score ≤1 were 92.7% and 60.0% respectively. HBV DNA levels had no association with liver histology.

Conclusion

Among HBeAg-positive patients with ALT ≤2×ULN, high serum HBsAg levels can accurately predict fibrosis score ≤1, and could potentially influence decisions concerning treatment commencement and reduce the need for liver biopsy.     

Prediction of Clinical Outcomes in Hepatitis B E Antigen Negative Chronic Hepatitis B Patients with Elevated Hepatitis B Virus DNA Levels

Objectives

We investigated whether long-term clinical outcomes such as disease progression or inactive hepatitis B virus (HBV) carrier state can be predicted by baseline factors in hepatitis B e antigen (HBeAg)-negative HBV infected patients with an elevated viral load.

Methods

A retrospective cohort of 527 HBeAg-negative chronic HBV infected patients with an elevated viral load (HBV DNA ≥ 2,000 IU/ml) was assessed for disease progression defined by the development of hepatocellular carcinoma (HCC) or cirrhotic complication, as well as becoming an inactive carrier.

Results

During a median 3.6 years of follow-up, disease progression was detected in 46 patients (40 with HCC, 6 with cirrhotic complication), and 31 of 309 non-cirrhotic patients became inactive carriers. Older age, male gender, cirrhosis, high HBV DNA levels at baseline, and short antiviral therapy duration were independent risk factors for HCC. Low HBV DNA and quantitative hepatitis B surface antigen (qHBsAg) levels were independent predictors for becoming inactive carriers in patients without cirrhosis. In non-cirrhotic patients with both low qHBsAg and HBV DNA levels, the 5-year cumulative incidence of an inactive carrier was 39.8%, while that of disease progression was 1.6%.

Conclusion

HBeAg negative patients without cirrhosis can be closely monitored for becoming an inactive carrier when both HBV DNA and qHBsAg levels are low, as the risk of disease progression is low while incidence of an inactive carrier is high.     

Hepatitis B Surface Antigen Quantity Positively Correlates with Plasma Levels of microRNAs Differentially Expressed in Immunological Phases of Chronic Hepatitis B in Children

Background and Aim

Children with chronic hepatitis B (CHB) are at high risk of progressive liver disease. It is suggested that a newly-identified panel of 16 microRNAs is important in the pathogenesis of CHB in children. Subviral hepatitis B surface antigen (HBsAg) particles are produced in large excess over infectious virions. Interestingly, circulating HBsAg particles have been shown to carry microRNAs. A thorough characterisation of the identified microRNAs and HBsAg over time in plasma from children with CHB may provide useful information about the natural course of childhood CHB.

Patients and Methods

A cohort of 42 children with CHB was followed over time. Three to five blood samples were obtained from each child at minimum intervals of half a year; in total 180 blood samples. Plasma levels of the 16 microRNAs previously identified were analysed by quantitative real-time polymerase-chain-reaction. Plasma HBsAg was quantified using ARCHITECT® HBsAg assay.

Results

The presence of 14/16 plasma microRNAs in children with CHB was confirmed. All 14 microRNAs were significantly differentially expressed in different immunological phases of the disease. MicroRNA plasma levels were highest in immune-tolerant children, lower in immune-active children, and reached the lowest values in immune-inactive children, p<0.001. Plasma levels of four microRNAs decreased significantly over time in immune-tolerant and immune-active children whereas the microRNA plasma levels were stable in immune-inactive children, p<0.004. HBsAg quantity was positively correlated with plasma levels of 11/14 microRNAs, p<0.004.

Conclusion

This is the first study to characterise plasma microRNAs and HBsAg over time in children with CHB. Our data suggest that plasma levels of selected microRNAs and HBsAg are inversely correlated with immunological control of CHB in children. Further studies are, however, needed to advance the understanding of microRNAs and HBsAg in the pathogenesis of CHB in children.     

慢性乙型肝炎及肝硬化患者幽门螺杆菌感染的临床特征分析

目的:分析慢性乙型肝炎及肝硬化患者幽门螺杆菌感染的临床特征。方法:选取2013年5月到2014年5月我院收治的胃镜检查患者58例,其中肝硬化患者17例(肝硬化组),慢性乙型肝炎患者22例(慢性乙型肝炎组),普通患者19例(普通组),根据肝硬化门脉高压的严重程度将患者分为轻型(5例)、中型(7例)和重型(5例),比较各组幽门螺杆菌的感染情况。结果:肝硬化组、慢性乙型肝炎组及普通组幽门螺杆菌感染率分别为23.5%,22.7%,21.1%,三组比较差异无统计学意义(x2=2.872,P=0.072);肝硬化轻、中、重患者幽门螺杆菌感染率分别为20.0%、28.6%、20.0%,三者比较无统计学意义(x2=1.892,P=0.082)。结论:慢性乙型肝炎、肝硬化及普通患者幽门螺杆菌感染情况相似,且幽门螺杆菌感染对肝硬化门静脉高压无影响。     

Rare Detection of Occult Hepatitis B Virus Infection in Children of Mothers with Positive Hepatitis B Surface Antigen

The prevalence of occult Hepatitis B virus (HBV) infection in children was considerably varied from 0.1–64% in different reports. In this study we aimed to investigate the prevalence of occult HBV infection among the children born to mothers with positive hepatitis B surface antigen (HBsAg) in Jiangsu, China. Serum samples were collected from 210 children of 207 mothers with positive HBsAg. HBV serological markers were detected by ELISA and HBV DNA was detected by nested PCR. Homology comparison of HBV sequences recovered from the child and mother was used to define the infection. Three children (1.43%) were positive for HBsAg, in whom the HBV pre S and S gene sequence in each child was identical to that in her mother. Of the 207 HBsAg-negative children, nine displayed HBV DNA positive by two nested PCR assays using primers derived from S and C genes. However, the sequence alignment showed that the sequences in each child were considerably different from those in his/her mother. Therefore, the sequences amplified from the children were very likely resultant from the cross-contaminations. Furthermore, the nine children with ‘positive HBV DNA’ were all negative for anti-HBc, and one had anti-HBs 3.42 mIU/ml and eight others had anti-HBs from 72 to >1000 mIU/ml, indicating that the nine children were less likely infected with HBV. Therefore, none of the 207 HBsAg-negative children of HBV-infected mothers was found to have occult HBV infection. We conclude that the prevalence of occult HBV infection in vaccinated children born to HBsAg positive mothers should be extremely low. We recommend that homology comparison of sequences recovered from the child and mother be used to define the occult HBV infection in children born to HBV infected mothers.     

Chronic Hepatitis B Virus Infection: The Relation between Hepatitis B Antigen Expression,Telomere Length,Senescence, Inflammation and Fibrosis

BackgroundChronic Hepatitis B virus (HBV) infection can lead to the development of chronic hepatitis, cirrhosis and hepatocellular carcinoma. We hypothesized that HBV might accelerate hepatocyte ageing and investigated the effect of HBV on hepatocyte cell cycle state and biological age. We also investigated the relation between inflammation, fibrosis and cell cycle phase.MethodsLiver samples from patients with chronic HBV (n = 91), normal liver (n = 55) and regenerating liver (n = 15) were studied. Immunohistochemistry for cell cycle phase markers and HBV antigens was used to determine host cell cycle phase. Hepatocyte-specific telomere length was evaluated by quantitative fluorescent in-situ hybridization (Q-FISH) in conjunction with hepatocyte nuclear area and HBV antigen expression. The effects of induced cell cycle arrest and induced cellular senescence on HBV production were assessed in vitro.Results13.7% hepatocytes in chronic HBV had entered cell cycle, but expression of markers for S, G2 and M phase was low compared with regenerating liver. Hepatocyte p21 expression was increased (10.9%) in chronic HBV and correlated with liver fibrosis. Mean telomere length was reduced in chronic HBV compared to normal. However, within HBV-affected livers, hepatocytes expressing HBV antigens had longer telomeres. Telomere length declined and hepatocyte nuclear size increased as HBV core antigen (HBcAg) expression shifted from the nucleus to cytoplasm. Nuclear co-expression of HBcAg and p21 was not observed. Cell cycle arrest induced in vitro was associated with increased HBV production, in contrast to
in vitro induction of cellular senescence, which had no effect.ConclusionChronic HBV infection was associated with hepatocyte G1 cell cycle arrest and accelerated hepatocyte ageing, implying that HBV induced cellular senescence. However, HBV replication was confined to biologically younger hepatocytes. Changes in the cellular location of HBcAg may be related to the onset of cellular senescence.     

Determinants of Vitamin D Status in Fair-Skinned Women of Childbearing Age at Northern Latitudes

Background and Objective

Poor vitamin D status during pregnancy has been associated with unfavorable outcomes for mother and child. Thus, adequate vitamin D status in women of childbearing age may be important. The aim of this study is to investigate the determinants of 25-hydroxyvitamin D (25(OH)D) serum concentrations in women of childbearing age living in Sweden, at latitude 57–58° north.

Method

Eighty four non-pregnant, non-lactating, healthy, fair-skinned women aged between 25–40 years were included. All subjects provided blood samples, four day food records and answered questionnaires about sun exposure and lifestyle. Total serum 25(OH)D was analyzed using Roche Cobas® electrochemoluminiescent immunoassay.

Results

Mean 25(OH)D was 65.8±19.9 nmol/l and 23% of the subjects had concentrations <50 nmol/l. Only 1% had concentrations <25 nmol/l. Determinants of 25(OH)D concentrations were recent sunbed use, recent travel to southern latitude, season, estrogen contraceptive use and use of supplementary vitamin D (R² = 0.27).

Conclusion

Every fifth woman had 25(OH)D concentrations <50 nmol/l. About 30% of the variation in vitamin D status was explained by sun exposure, use of vitamin D supplements and use of estrogen contraceptives. Cutaneous vitamin D synthesis seems to be a major contributor to vitamin D status, even at northern latitudes. Thus, recommendations on safe UV-B exposure could be beneficial for vitamin D status.     

A Mechanism To Explain the Selection of the Hepatitis e Antigen-Negative Mutant during Chronic Hepatitis B Virus Infection

Hepatitis B virus (HBV) expresses two structural forms of the nucleoprotein, the intracellular nucleocapsid (hepatitis core antigen [HBcAg]) and the secreted nonparticulate form (hepatitis e antigen [HBeAg]). The aim of this study was to evaluate the ability of HBcAg- and HBeAg-specific genetic immunogens to induce HBc/HBeAg-specific CD4⁺/CD8⁺ T-cell immune responses and the potential to induce liver injury in HBV-transgenic (Tg) mice. Both the HBcAg- and HBeAg-specific plasmids primed comparable immune responses. Both CD4⁺ and CD8⁺ T cells were important for priming/effector functions of HBc/HBeAg-specific cytotoxic T-lymphocyte (CTL) responses. However, a unique two-step immunization protocol was necessary to elicit maximal CTL priming. Genetic vaccination did not prime CTLs in HBe- or HBc/HBeAg-dbl-Tg mice but elicited a weak CTL response in HBcAg-Tg mice. When HBc/HBeAg-specific CTLs were adoptively transferred into HBc-, HBe-, and HBc/HBeAg-dbl-Tg mice, the durations of the liver injury and inflammation were significantly greater in HBeAg-Tg recipient mice than in HBcAg-Tg mice. Importantly, liver injury in HBc/HBeAg-dbl-Tg mice was similar to the injury observed in HBeAg-Tg mice. Loss of HBeAg synthesis commonly occurs during chronic HBV infection; however, the mechanism of selection of HBeAg-negative variants is unknown. The finding that hepatocytes expressing wild-type HBV (containing both HBcAg and HBeAg) are more susceptible to CTL-mediated clearance than hepatocytes expressing only HBcAg suggest that the HBeAg-negative variant may have a selective advantage over wild-type HBV within the livers of patients with chronic infection during an immune response and may represent a CTL escape mutant.     

Effects of Entecavir on Hepatitis B Virus Covalently Closed Circular DNA in Hepatitis B e Antigen-Positive Patients with Hepatitis B

The aim of this study was to assess the effect of 48-week entecavir therapy on serum and intrahepatic hepatitis B virus, covalently closed circular DNA (HBV cccDNA) levels in hepatitis B e antigen (HBeAg)-positive patients. A total of 120 patients with HBeAg-positive chronic hepatitis were treated with entecavir for 48 weeks. Serum HBV markers, total HBV DNA, and HBV cccDNA levels were measured at baseline and week 48. Biopsies from 20 patients were available for both intrahepatic total HBV DNA and cccDNA testing at these timepoints. HBV cccDNA levels were decreased from a median level of 5.1×10⁶ copies/mL at baseline to a median level of 2.4×10³ copies/mL at week 48. Reduction magnitudes of HBV cccDNA in patients with normalized alanine aminotransferase levels and those undergoing HBeAg seroconversion were significantly greater than those in alanine aminotransferase-abnormal and HBeAg positive patients. Intrahepatic HBV cccDNA was decreased significantly after 48 weeks of treatment, but could not be eradicated. In conclusion, treatment of HBeAg-positive hepatitis B patients with entecavir for 48 weeks decreased serum and intrahepatic HBV cccDNA significantly, and the magnitude of HBV cccDNA reduction was related to total HBV DNA decrease, alanine aminotransferase normalization, and HBeAg seroconversion.     

Virus-Specific Immune Response in HBeAg-Negative Chronic Hepatitis B: Relationship with Clinical Profile and HBsAg Serum Levels

Background & Aims

The immune impairment characterizing chronic hepatitis B (cHBV) infection is thought to be the consequence of persistent exposure to viral antigens. However, the immune correlates of different clinical stages of cHBV and their relation with different levels of HBsAg have not been investigated. The aim of the present study was to evaluate the relationship between HBV-specific T cells response and the degree of in vivo HBV control and HBsAg serum levels in HBeAg-HBeAb+ cHBV.

Methods

Peripheral blood mononuclear cells from 42 patients with different clinical profiles (treatment-suppressed, inactive carriers and active hepatitis) of cHBV, 6 patients with resolved HBV infection and 10 HBV-uninfected individuals were tested with overlapping peptides spanning the entire HBV proteome. The frequency and magnitude of HBV-specific T cell responses was assessed by IFNγ ELISPOT assay. Serum HBsAg was quantified with a chemiluminescent immunoassay.

Results

The total breadth and magnitude of HBV-specific T cell responses did not differ significantly between the four groups. However, inactive carriers targeted preferentially the core region. In untreated patients, the breadth of the anti-core specific T cell response was inversely correlated with serum HBsAg concentrations as well as HBV-DNA and ALT levels and was significantly different in patients with HBsAg levels either above or below 1000 IU/mL. The same inverse association between anti-core T cell response and HBsAg levels was found in treated patients.

Conclusions

Different clinical outcomes of cHBV infection are associated with the magnitude, breadth and specificity of the HBV-specific T cell response. Especially, robust anti-core T cell responses were found in the presence of reduced HBsAg serum levels, suggesting that core-specific T cell responses can mediate a protective effect on HBV control.     

Plasma Levels of Trace Elements Have an Implication on Interferon Treatment of Children with Chronic Hepatitis B Infection

This study evaluated the plasma levels of trace elements in children with chronic hepatitis B virus (HBV) infection and assessed whether they can be a factor that affects the response to interferon alpha (IFN-α) treatment. The study included 35 cases (ten girls, 25 boys) aged 3–13 years with chronic HBV infection and the control group. Plasma levels of copper (Cu), manganese (Mn), molybdenum (Mo), selenium (Se), and zinc (Zn) were measured before IFN-α treatment and biochemical, virological, and histopathologic response to treatment were assessed. Children were followed for at least 15 months. Although plasma Cu levels showed no difference between the groups, Mn, Mo, Se, and Zn levels were significantly lower in the study group before treatment. Fourteen cases (40%) showed biochemical response; 17 (48.6%) showed virological response; 16 (47.6%) showed histopathologic response, and ten (28.6%) showed response according to all three parameters. Plasma Cu and Mn levels of patients with triple response showed no difference; but Mo, Se, and Zn levels were significantly lower (p?<?0.001) in the study group. No difference was observed between responders and nonresponders (p?>?0.05). Plasma levels of Mn, Mo, Se, and Zn are lower in children with chronic HBV infection compared to healthy children. The pretreatment levels of these elements did not show difference between responders and nonresponders to IFN-α.     

Age as a Predictor of Significant Fibrosis Features in HBeAg-Negative Chronic Hepatitis B Virus Infection with Persistently Normal Alanine Aminotransferase

Background

Although alanine aminotransferase (ALT) levels reflect the degree of liver damage, not all patients with chronic hepatitis B virus (HBV) infection exhibit persistently elevated ALT levels. In the present study, we aimed to comprehensively evaluate the characteristics of histological abnormalities in a large population of Chinese patients with chronic HBV and persistently normal ALT levels.

Methods

In total, 2303 consecutive patients who underwent liver biopsy were screened. Of these patients, 273 were categorized as having persistently normal ALT levels (PNALT), whereas 618 were categorized as having persistently or intermittently elevated ALT levels (PIALT). All these patients had at least three ALT values recorded in the year prior to the baseline liver biopsy.

Results

Significant necroinflammation was observed in 9.7% (11/113) patients with PNALT, 23.3% (42/180) patients with PIALT (ALT 1–2× upper limit of normal [ULN]), and 27.8% (42/151) patients with PIALT (ALT > 2× ULN), whereas significant fibrosis was observed in 8.8% (10/113) patients with PNALT, 27.8% (42/151) patients with PIALT (ALT 1–2× ULN), and 21.2% (32/151) patients with PIALT (ALT > 2× ULN). Multiple logistic regression analysis indicated that age parameters were associated with significant histological abnormalities in patients with PNALT. The area under the curve showed that age was associated with significant fibrosis characteristics in patients with hepatitis B extracellular antigen (HBeAg)-negative PNALT.

Conclusion

Significant histological abnormalities are not often observed in Chinese patients with PNALT. Interestingly, age appears to be a predictor of significant fibrosis in patients with HBeAg-negative PNALT.     

沈阳市居民乙肝感染状况调查

对不同性别、年龄的沈阳市居民乙型肝炎病毒血清标志物进行检测,分析HBV感染状况。采集3 780名健康体检者血清标本检测乙肝5项、ALT和TBIL,统计分析后的结果显示:乙肝感染率为3.28%,不同性别间结果无明显差异(P>0.05),但不同年龄组间乙肝感染率有显著差异(P<0.01),41～50岁年龄组感染率是6.23%,30岁以下和50岁以上感染率较低,分别为2.94%和1.84%;1、4、5感染模式占总感染例数的69.4%,HBV感染者中ALT或TBIL单项升高及二者均升高者占22.6%。沈阳市居民乙肝感染率低于全国平均水平,慢性乙肝感染较多,肝功能与乙肝感染病程不呈平行关系,疫苗接种可有效预防乙肝感染。     

Interferon-Alpha-2a and Zinc Combination Therapy in Children with Chronic Hepatitis B Infection

Zinc has been reported to enhance the response to interferon (IFN) or PEG-IFN plus ribavirin therapy, improve liver function, and ameliorate hematologic side effects in patients with chronic hepatitis C. However, the role of zinc supplementation during IFN therapy in chronic hepatitis B infection (CHB) remains unclear. We therefore aimed to report the results of zinc and IFN-alpha-2a therapy in children with CHB. Twenty-two naive, HBeAg-positive children (mean age 10.4 ± 4.4 years) received IFN-α2a (9 MU/m² sc) for 6 months plus peroral zinc (7.5 mg/day for <10 years and 10 mg/day for >10 years) for 12 months. Serum zinc, alanine aminotransferase (ALT), complete blood count, hepatitis B virus DNA (HBV DNA), and serological markers were measured. Histological (HR) and sustained response (SR) were evaluated at 6 months after completion of therapy. Normalization of ALT, HBeAg seroconversion, and HBV DNA < 10,000 copies/ml were considered as SR. HR was defined as decrease in Knodell histological activity index (HAI) score by at least 2 points compared to baseline. End of therapy ALT level and log HBV DNA were significantly lower than pretherapy levels (p = 0.001 and p = 0.001, respectively), while zinc level was not different. Portal inflammation score significantly decreased after therapy (p = 0.043), however, total HAI and other HAI components were not different. SR and HR were 25% and 52.9%. In conclusion as a first study investigating the effect of zinc and IFN combination therapy in children with CHB, SR and HR rates were not better than previously reported monotherapy or combination therapies.     

Subtypes of Hepatitis B Antigen in Blood Donors and Post-transfusion Hepatitis: Clinical and Epidemiological Aspects

Subtyping of hepatitis B antigen (HBA) in blood donors revealed subtype ad in 56% while patients with icteric post-transfusion hepatitis from the same centre showed subtype ay in the majority of the cases (75%). Donors with subtype ad in serum were mostly asymptomatic long-term carriers of the antigen with normal liver function (83%), while 70% of donors with subtype ay in serum had signs of acute or chronic liver disease. Healthy long-term carriers of HBA seem to present little risk of transmitting hepatitis irrespective of subtype. It is, however, possible that these differences in blood donors with subtype ad and patients with post-transfusion hepatitis with subtype ay might reflect epidemiological circumstances rather than biological differences in the two viral strains.     

甲型肝炎、乙型肝炎病毒混合抗原的细胞免疫学研究

评价甲型肝炎病毒和乙型肝炎病毒混合抗原对细胞免疫反应的影响。采用小鼠迟发型超敏反应(DTH)、脾脏淋巴细胞增殖实验和淋巴细胞亚型分群实验 ,对甲肝抗原 (HAAg)、乙肝表面抗原 (HBsAg)和甲乙肝混合抗原 (HAAg +HBsAg)进行检测 ,并进行统计学分析。混合抗原没有降低相应单价抗原的各项细胞免疫反应强度 ,且较单一 ,HBsAg表现出了显著的抗原特异性T淋巴细胞和Th2细胞增殖作用 (P <0 .0 5 )。混合抗原表现出良好的细胞免疫反应原性 ,同时可能辅助B细胞 ,增强体液免疫应答能力。     

突变型乙肝病毒核心抗原DNA疫苗的体外表达

目的:构建突变型核心抗原核酸疫苗,观察该核酸疫苗在体外蛋白的表达.方法:采用基因工程定点突变技术,构建5种突变型核酸疫苗,分别去除乙肝病毒核心抗原N端的第1、2位氨基酸,命名为M12,去除3、4位氨基酸命名为M34以及去除5、6位的氨基酸命名为M56,用上述构建的核酸疫苗与野生型HBc核酸疫苗(pJW4303/Hc)及空载体质粒pJW4303分别用脂质体转染293T细胞,应用蛋白印迹法检测核心蛋白的表达.结果:经过pstl和BgI双酶切和测序鉴定结果突变型核心抗原核酸疫苗构建成功.在去除2个氨基酸的核酸疫苗结果中显示:野生型pJW4303/HBe、M12、及M56体外转染293T细胞后,在细胞上清和裂解中能很好的表达,而M34上清未见表达,仅裂解中可见极少量疑似表达条带;在原有基础上分别去除第3位和第4住氨基酸,命名为M3和M4,结果显示M3上清未见表达,裂解液中可见少量表达,而M4在上清和裂解中均可见明显的表达.结论:去除核心抗原N端第3位的氨基酸(M3)可以明显影响核心抗原的表达,HBcAg氨基端第3位氨基酸对蛋白的表达可能起到重要的作用.     

The Iodine Status and Prevalence of Thyroid Disorders Among Women of Childbearing Age in China: National Cross-sectional Study

ObjectiveMandatory universal salt iodization in China was implemented 20 years ago. However, the current iodine status and prevalence of thyroid disorders among childbearing-age women are unknown.MethodsA nationally representative cross-sectional study with 26 166 enrolled participants aged 18 to 49 years from all 31 provincial regions of mainland China was performed. The participants were given a questionnaire and underwent B-mode ultrasonography of the thyroid. The serum concentrations of thyroid hormones and thyroid antibodies and the urinary iodine concentration (UIC) were measured.ResultsThe median UIC was 178.7 μg/L, indicative of adequate iodine status. pHowever, 19.04% and 19.87% of the participants were classified as having iodine deficiency and excessive iodine, respectively. The weighted prevalence of thyroid disorders was as follows: 1.08% had overt hyperthyroidism, 0.58% had subclinical hyperthyroidism, 0.76% had Graves disease, 1.28% had overt hypothyroidism, 14.28% had subclinical hypothyroidism, 13.53% were positive for thyroid peroxidase antibodies, and 14.55% were positive for thyroglobulin antibodies. Excessive iodine and overweight were associated with higher odds of subclinical hypothyroidism. A family history of thyroid disorders and an age between 40 and 49 years were significantly associated with higher odds of positivity for thyroid peroxidase antibodies and thyroglobulin antibodies.ConclusionIodine deficiency, excessive iodine, subclinical hypothyroidism, and positivity for thyroid autoantibodies remain prevalent among women of childbearing age in China. Women of childbearing age who are relatively older, are overweight, or have a family history of thyroid disorders are encouraged to undergo active screening of their UIC and thyroid function when planning a pregnancy.