Thyroid nodules in centenarians: prevalence and relationship to lifestyle characteristics and dietary habits

Gut Microbiota Changes and Its Potential Relations with Thyroid Disorders: From Composition to Therapeutic Targets

Composed of over 1200 species of anaerobes and aerobes bacteria along with bacteriophages, viruses, and fungal species, the human gut microbiota (GM) is vital to health, including digestive equilibrium, immunologic, hormonal, and metabolic homeostasis. Micronutrients, usually refer to trace elements (copper, iodine, iron, selenium, zinc) and vitamins (A, C, D, E), interact with the GM to influence host immune metabolism. So far, microbiome studies have revealed an association between disturbances in the microbiota and various pathological disorders, such as anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, anxiety, depression, early-onset cancers, type 1 diabetes (T1D) and type 2 diabetes (T2D). As common conditions, thyroid diseases, encompassing Graves' disease (GD), Graves' orbitopathy (GO), Hashimoto's thyroiditis (HT), benign nodules, and papillary thyroid cancer (TC), have negative impacts on the health of all populations. Following recent studies, GM might play an integral role in triggering diseases of the thyroid gland. Not only do environmental triggers and genetic predisposing background lead to auto-aggressive damage, involving cellular and humoral networks of the immune system, but the intestinal microbiota interacts with distant organs by signals that may be part of the bacteria themselves or their metabolites. The review aims to describe the current knowledge about the GM in the metabolism of thyroid hormones and the pathogenesis of thyroid diseases and its involvement in the appearance of benign nodules and papillary TC. We further focused on the reciprocal interaction between GM composition and the most used treatment drugs for thyroid disorders. However, the exact etiology has not yet been known. To elucidate more precisely the mechanism for GM involvement in the development of thyroid diseases, future work is needed.

Analysis of Related Factors Influencing Hypertension Classification among Centenarians in Hainan, China

Background

As a population ages, blood pressure levels gradually increase, leading to a higher incidence of hypertension and increased cardiovascular diseases risk. This study examines factors affecting hypertension grading among centenarians in the Hainan Province.

Methods

Data from 2014 to 2016 were accessed from the cross-sectional database "Hypertension Levels and Epidemiological Characteristics of the Elderly and Centenarians in Hainan province of China". This study included 690 centenarians with hypertension. Hypertension grading was the dependent variable, analyzed against independent variables including demographic information (sex, age, ethnicity, education level, marital status, cohabitation, and regional distribution), lifestyle factors (smoking, alcohol consumption, and physical activity), body mass index (BMI), and comorbid conditions (diabetes and hyperlipidemia). Logistic regression models, adjusted for these factors, were used to assess the determinants of hypertension grading among the participants.

Results

Multivariate regression analysis, after adjusting for other variables, revealed significant associations between BMI, low-density lipoprotein (LDL) levels, and hypertension grades. Individuals with BMI below 18.5 kg/m 2 had a 0.614-fold lower risk of developing grade III hypertension (odds ratio [OR]: 0.614, 95% confidence interval [CI]: 0.390-0.966, p = 0.0350) and a 0.586-fold lower risk for grade II hypertension (OR: 0.586, 95% CI: 0.402-0.852, p = 0.0052). Furthermore, individuals with elevated LDL levels had a 6.087-fold greater risk of progressing from grade I to grade III hypertension (OR: 6.087, 95% CI: 1.635-22.660, p = 0.0071) and a 4.356-fold greater risk of progressing from grade II to grade III hypertension (OR: 4.356, 95% CI: 1.052-18.033, p = 0.0423). Additionally, individuals of Li ethnicity had 1.823-fold greater risk of progressing from grade I to grade II hypertension compared to those of Han ethnicity (OR: 1.823, 95% CI: 1.033-3.218, p = 0.0383).

Conclusions

A BMI below 18.5 kg/m 2 , elevated LDL, and ethnicity emerged the primary factors associated with hypertension grading in centenarians. To reduce the risk of hypertension, it is crucial for centenarians to maintain a healthy weight, normal LDL levels, and adopt dietary habits including a low-cholesterol and low-fat diet.

Establishment and validation of a multivariate logistic model for risk factors of thyroid nodules using lasso regression screening

Objective

This study aims to analyze the association between the occurrence of thyroid nodules and various factors and to establish a risk factor model for thyroid nodules.

Methods

The study population was divided into two groups: a group with thyroid nodules and a group without thyroid nodules. Regression with the least absolute shrinkage and selection operator (Lasso) was applied to the complete dataset for variable selection. Binary logistic regression was used to analyze the relationship between various influencing factors and the prevalence of thyroid nodules.

Results

Based on the screening results of Lasso regression and the subsequent establishment of the Binary Logistic Regression Model on the training dataset, it was found that advanced age (OR=1.046, 95% CI: 1.033-1.060), females (OR = 1.709, 95% CI: 1.342-2.181), overweight individuals (OR = 1.546, 95% CI: 1.165-2.058), individuals with impaired fasting glucose (OR = 1.590, 95% CI: 1.193-2.122), and those with dyslipidemia (OR = 1.588, 95% CI: 1.197-2.112) were potential risk factors for thyroid nodule disease (p<0.05). The area under the curve (AUC) of the receiver operating characteristic (ROC) curve for the Binary Logistic Regression Model is 0.68 (95% CI: 0.64-0.72).

Conclusions

advanced age, females, overweight individuals, those with impaired fasting glucose, and individuals with dyslipidemia are potential risk factors for thyroid nodule disease.

Management of thyroid dysfunction and thyroid nodules in the ageing patient

Thyroid dysfunction is a common endocrine disorder in the general population, with a reported prevalence of 10-15%. However, this rate is even higher in older adults, with an estimated prevalence of ≈25% in some populations. Since elderly patients usually present more comorbidities than younger individuals, thyroid dysfunction may carry a synergistic negative health impact, mainly due to increased cardiovascular disease risk. Moreover, thyroid dysfunction in the elderly can be more difficult to diagnose due to its subtle or even asymptomatic clinical presentation, and the interpretation of thyroid function tests may be affected by drugs that interfere with thyroid function or by the coexistence of several diseases. On the other hand, thyroid nodules are also a prevalent condition in older adults, and its incidence increases with age. The assessment and management of thyroid nodules in the ageing patient should take into account several factors, as risk stratification, thyroid cancer biology, patient´s overall health, comorbidities, treatment preferences, and goals of care. In this review article, we summarize the current knowledge on the pathophysiology, diagnosis, and therapeutic management of thyroid dysfunction in elderly patients and we also review how to identify and manage thyroid nodules in this population.

Will metformin use lead to a decreased risk of thyroid cancer? A systematic review and meta-analyses

BACKGROUND

It has been reported that metformin use may reduce the risk of thyroid cancer, but existing studies have generated inconsistent results. The purpose of this study was to investigate such association between metformin use and the risk of thyroid cancer.

METHODS

Studies of metformin use for the risk of thyroid cancer were searched in Web of Science, PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, China Biomedical Database, Wanfang Data, and Chinese Scientific Journals Database (VIP) from the establishment date to December 2022. Newcastle-Ottawa scale is adopted for assessing the methodological quality of included studies, and the inter-study heterogeneity was assessed by using the I-squared statistic. Combined odds ratios (ORs) with the corresponding 95% confidence intervals (CIs) were calculated through either fixed-effects or random-effects model according to the heterogeneity. Besides, subgroup analyses, sensitivity analyses and test for publication bias were conducted.

RESULTS

Five studies involving 1,713,528 participants were enrolled in the qualitative and quantitative synthesis. The result of the meta-analyses showed that metformin use was associated with a statistically significant lower risk of thyroid cancer (pooled OR = 0.68, 95% CI = 0.50-0.91, P = 0.011). Moreover, in the subgroup analysis, we found that the use of metformin may also aid in the prevention of thyroid cancer in Eastern population (pooled OR = 0.55, 95% CI = 0.35-0.88, P = 0.012) rather than Western population (pooled OR = 0.89, 95% CI = 0.52-1.54, P = 0.685). Sensitivity analysis suggested the results of this meta-analyses were relatively stable. No publication bias was detected.

CONCLUSION

Metformin use is beneficial for reducing the risk of thyroid cancer. For further investigation, more well-designed studies are still needed to elucidate the association between metformin use and the risk of thyroid cancer.

Thyroid Nodules and Obesity

A widely discussed topic in the pathophysiology of thyroid nodules is the role of obesity, a state that leads to increased systemic inflammatory markers. Leptin plays a vital role in forming thyroid nodules and cancer through several mechanisms. Together with chronic inflammation, there is an augmentation in the secretion of tumor necrosis factor (TNF) and the cytokine interleukin 6 (IL-6), which contributed to cancer development, progression and metastasis. In addition, leptin exerts a modulatory action in the growth, proliferation and invasion of thyroid carcinoma cell lines via activating various signal pathways, such as Janus kinase/signal transducer and activator of transcription, mitogen-activated protein kinase (MAPK) and/or phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt). Through several proposed mechanisms, aberrant endogenous estrogen levels have been suggested to play a vital role in the development of both benign and malignant nodules. Metabolic syndrome triggers the development of thyroid nodules by stimulating thyroid proliferation and angiogenesis due to hyperinsulinemia, hyperglycemia and dyslipidemia. Insulin resistance influences the distribution and structure of the thyroid blood vessels. Insulin growth factor 1 (IGF-1) and insulin affect the regulation of the expression of thyroid genes and the proliferation and differentiation of thyroid cells. TSH can promote the differentiation of pre-adipocytes to mature adipocytes but also, in the presence of insulin, TSH possesses mitogenic properties. This review aims to summarize the underlying mechanisms explaining the role of obesity in the pathophysiology of thyroid nodules and discuss potential clinical implications.

Prevalence of Thyroid Nodules and Associated Clinical Characteristics: Findings from a Large Sample of People Undergoing Health Checkups at a University Hospital in Vietnam

Background

Thyroid nodule is a common disorder normally detected by ultrasound. However, little is known about the population prevalence of thyroid nodules in a Vietnamese population. This study aimed to estimate the prevalence of thyroid nodules, its characteristics, and associated factors in a large number of people undergoing annual health checkups.

Methods

A retrospective, cross-sectional descriptive study was conducted, based on electronic medical records of people undergoing health checkups at the Health Checkup Department, University Medical Center at Ho Chi Minh City. All of the participants underwent thyroid ultrasonography, anthropometric measurements, and serum examinations.

Results

A total of 16,784 participants (mean age: 40.4 ± 12.7 years, 45.1% female) were included in this study. The overall prevalence of thyroid nodules was 48.4%. The mean diameter of nodules was 7.2 ± 5.8 mm. The prevalence of nodules with malignant characteristics was 36.9%. Women had a significantly higher prevalence of thyroid nodules than men (55.2% vs 42.9%, p<0.001). Advanced age, hypertension, and hyperglycemia were significantly associated with thyroid nodules in both genders. In men, significant factors also included increased body mass index. In women, these included increased total cholesterol and LDLc, hypertriglyceridemia, and hyperuricemia.

Conclusion

This study showed a high prevalence of TNs in Vietnamese people undergoing general health checkups. Importantly, the proportion of TNs with malignant risk was quite high. Therefore, screening for TNs should be added to annual health checkups to improve early detection of TNs, targeting those who have a high-risk profile based on factors identified in this study.

Ultrasound-Based Risk Stratification System for the Assessment of Partially Cystic Thyroid Nodules

OBJECTIVE

To develop and validate a risk stratification system for the prediction of malignancy in Partially Cystic Thyroid Nodules (PCTNs).

METHODS

From January 2020 to December 2021, we retrospectively reviewed the sonography data of PCTNs patients from Hangzhou TCM Hospital, Hangzhou First People's Hospital two medical centers. The independent risk factors of malignant PCTNs were evaluated using univariate and multivariate logistic regression analysis. The nomogram prediction efficiency was assessed using Area Under the Curve (AUC) and calibration curves. To determine the clinic value of the predictive model, Decision Curve Analysis (DCA) was used.

RESULTS

In this retrospective study, a total of 285 patients (301 PCTNs) were enrolled, 242 nodules were benign, and 59 nodules were malignant. Younger age, hypoechoic, irregular margin and microcalcifications were found to be the independent risk factors associated with malignant PCTNs. The AUC, sensitivity, and specificity were 0.860, 77.1%, and 84.7% in the training set and 0.897, 91.7%, and 87.0% in the external validation set, respectively. The total point of nomogram is greater than 161, which shows the best to predict the malignancy of PCTNs.

CONCLUSIONS

Our findings demonstrated that the risk stratification system for the assessment of PTCNs showed good prediction capacities.

Prevalence and Associated Predictors of Hypertension in Adult Patients with Thyroid Nodules at the Royal Commission Hospital, Kingdom of Saudi Arabia

Background

Hypertension and thyroid nodules (TNs) are common medical problems that are increasing in prevalence globally. Hence, we conducted this study to assess the prevalence and associated predictors of hypertension in adult patients with TNs at the Royal Commission Hospital, Kingdom of Saudi Arabia (KSA).

Methods

A retrospective study was conducted between 1 January 2015 and 31 December 2021. Patients with documented TNs based on the Thyroid Imaging Reporting and Data System (TI-RADS) were recruited to assess the prevalence and associated risk factors for hypertension.

Result

Three hundred ninety-one patients with TNs were recruited for this study. The median (interquartile range, IQR) age was 46.00 (20.0) years, and 332 (84.9%) of the patients were females. The median (IQR) body mass index (BMI) was 30.26 (7.71) kg/m². There was a high prevalence of hypertension (22.5%) in adult patients with TNs. In the univariate analysis, there were significant associations between diagnosed hypertension in patients with TNs and age, sex, diabetes mellitus (DM), bronchial asthma, triiodothyronine (FT3), total cholesterol and high-density lipoprotein (HDL). In the multivariate analysis, age (OR = 1.076 [95% CI 1.048 - 1.105]), sex (OR = 2.28 [95% CI 1.132 - 4.591]), DM (OR = 0.316 [95% CI 0.175 - 0.573]) and total cholesterol levels (OR = 0.820 [95% CI 0.694 - 0.969]) were significantly associated with hypertension.

Conclusion

There is a high prevalence of hypertension in patients with TNs. Age, female sex, DM and elevated total cholesterol are significant predictors of hypertension in adult patients with TNs.

Prevalence of thyroid nodules and its association with water iodine among Chinese men and women

BACKGROUND

Because of the large change in iodine nutrition and other lifestyle in China, there is concern that thyroid nodules (TNs) may become epidemic. However, few data are currently available on the national prevalence of TNs. In addition, whether excess iodine in drinking water is associated with an increased risk of TNs, following universal salt iodization, has been less studied. We aim to estimate a national prevalence of TNs and its association with drinking water iodine.

METHODS

We conducted a national survey of 9,381,032 adults, aged 18 years or older, from 30 provinces and municipalities in China, who underwent a thyroid ultrasound test from January 2018 to December 2018. Crude and standardized prevalence of TNs were estimated. We further evaluated the ecological association between province- or city-specific iodine levels in drinking water and the prevalence of TNs using linear regression.

RESULTS

The age-standardized prevalence of TNs in men, women, and both sexes were 29.8%, 44.7%, and 37.1%, respectively. The prevalence increased with age from 22.7% (18-30 years) to 71.5% (≥70 years), and body mass index from 26.1% (<18.5 kg/m2) to 40.8% (≥28 kg/m2). Participants living in the eastern, northern, and northeastern regions had a higher prevalence of TNs (ranged from 38.7% to 43.7%) than those in other regions (ranged from 30.1% to 35.5%). The coastal residents (40.1%) had a higher prevalence of TNs than those in inlanders (35.4%). Higher levels of iodine in drinking water were linearly associated with increased prevalence of TNs, with Pearson correlation coefficients of 0.47 (P < 0.01) in men, 0.40 (P = 0.03) in women, and 0.46 (P = 0.01) in overall participants.

CONCLUSION

This was a nationwide prevalence study of TNs in China, showing that TNs were common health problems, and increased concentration of iodine in drinking water was associated with a higher prevalence of TNs.

Adherence to the Mediterranean Diet as a Modifiable Risk Factor for Thyroid Nodular Disease and Thyroid Cancer: Results From a Pilot Study

Iodine deficiency is the most important established nutritional risk factor for the development of thyroid nodular disease. Nevertheless, to the best of our knowledge, to date no study focused on the association between the adherence to the Mediterranean diet (MD) and thyroid nodular disease. Adherence to the MD was evaluated using the PREvención con DIetaMEDiterránea (PREDIMED) questionnaire. Physical activity, smoking habits, and anthropometric parameters were studied. PREDIMED was used to evaluate the degree of adherence to the MD. Evaluation of fine needle aspiration cytology of thyroid lesions based on 2013 Italian thyroid cytology classification system. Cytology of thyroid nodules was carried out through sonography-guided fine-needle aspiration and patients were divided into 5 categories: TIR2, TIR3a, TIR3b, TIR4, and TIR5. The study population consisted of 794 subjects (554 females, 69.8%), aged 18–65 years, with BMIs ranging from 19.4 to 55.3 kg/m². Thyroid nodular disease was present in 391 participants (49.2%), and the most frequent cytological categories was TIR2 (18.3 %), followed by a TIR4 (8.9 %). The presence of thyroid nodules was also significantly associated with the lowest adherence to the MD (OR 6.16, p < 0.001). Patients with TIR5 had the lower adherence to the MD (2.15 ± 1.12 score) compared to other TIRs (p < 0.001). The cytological category with high-risk of malignancy (TIR4/TIR5) was significantly associated with the lowest adherence to the MD (OR 137.55, p < 0.001) and PREDIMED score (OR = 0.33, p < 0.001, 95% IC = 0.26–0.41, R² = 0.462). At multiple regression analysis, PREDIMED score was the main predictor of both the presence of nodules (p < 0.001) and the cytological category with high-risk of malignancy (p < 0.001). At ROC analysis PREDIMED score ≤ 5 and ≤ 4 (p = 0.001) were the values that predicted the presence of thyroid nodular disease and cytological category with high-risk of malignancy, respectively. In conclusion, our study demonstrated that the low adherence to the MD is associated with the presence of thyroid nodular disease and in particular with those at high-risk of malignancy.

The prevalence of thyroid nodules and its factors among Chinese adult women: A cross-sectional study

OBJECTIVE

To determine the prevalence of thyroid nodules in Chinese adult women. To analyze the relationships between lifestyle, metabolic syndrome and thyroid nodules.

METHODS

We conducted a retrospective cross-sectional study in the tertiary hospital from 2017 to 2019. Included participants underwent thyroid color Doppler ultrasonography, lipids examination, and dietary evaluation.

RESULTS

Totally 2,784 participants were included, and 933 participants were found to have thyroid nodule(s) by B-ultrasound. The prevalence of thyroid nodules was 33.3%. Women in 50-59 years (OR: 1.746, 95% CI [1.356-2.249]), older than 60 (2.147 [1.540-2.993]) and occupations with mainly manual work (1.780 [1.367-2.317]) were risk factors for thyroid nodules, while moderate dietary diversity (0.624 [0.476-0.817]) and normal triglycerides level (0.739 [0.604-0.905]) were protective factors.

CONCLUSION

Women over 50 and those whose jobs are mainly manual should enhance screening, follow-up and health management of thyroid nodules. Higher dietary diversity is protective measures against thyroid nodules for adult women and should consider dietary balance and the food varieties, not just increased quantities.

Relationship between TSHR, BRAF and PIK3CA gene copy number variations and thyroid nodules

PURPOSE

This study aims to investigate the relationship between the TSHR, BRAF, and PIK3CA gene copy number variations (CNVs) and thyroid nodules by analyzing gene CNVs, and to explore the interaction between iodine status and the above genes CNVs in the occurrence of thyroid nodules.

METHODS

Three hundred and ninety-five subjects were selected from 3 regions with different iodine status in Shanxi Province of China, including 192 patients with thyroid nodules and 203 healthy controls. The basic information about subjects had been obtained through a questionnaire. B ultrasound was utilized to check thyroid nodules. Blood and urine samples were harvested to detect the thyroid function and urinary iodine concentration. Real-time quantitative polymerase chains reaction (RT-PCR) served to detect CNVs in DNA from human blood.

RESULTS

There was an association between TSHR gene CNV and thyroid nodules (χ² = 8.403, P = 0.004). The prevalence of BRAF and PIK3CA gene CNVs was not statistically significant between the case group and the control group. Differences in the TSHR gene CNV rates for cases of the 3 areas were statistically significant (χ² = 10.072, P = 0.007). No statistical difference in the prevalence rates of the 3 genes CNVs between diverse characteristics of thyroid nodules was observed. UIC > 300 μg/L (OR = 1.74, 95% CI: 1.02-2.96, P = 0.041) and TSHR gene CNV (OR = 3.53, 95% CI: 1.40-8.92, P = 0.008) were risk factors for thyroid nodules. There was no significant interaction between the UIC and the examined genes CNVs.

CONCLUSIONS

TSHR gene CNV and high urinary iodine levels can increase the risk of thyroid nodules. But the interactions between the 3 above genes CNVs and iodine nutrition were not found in the occurrence of thyroid nodules.

Gut Microbiome Alterations in Patients With Thyroid Nodules

Thyroid nodules are found in nearly half of the adult population. Accumulating evidence suggests that the gut microbiota plays an important role in thyroid metabolism, yet the association between gut microbiota capacity, thyroid nodules, and thyroid function has not been studied comprehensively. We performed a gut microbiome genome-wide association study in 196 patients with thyroid nodules and 283 controls by using whole-genome shotgun sequencing. We found that participants with high-grade thyroid nodules have decreased number of gut microbial species and gene families compared with those with lower grade nodules and controls. There are also significant alterations in the overall microbial composition in participants with high-grade thyroid nodules. The gut microbiome in participants with high-grade thyroid nodules is characterized by greater amino acid degradation and lower butyrate production. The relative abundances of multiple butyrate producing microbes are reduced in patients with high-grade thyroid nodules and the relative abundances of L-histidine metabolism pathways are associated with thyrotropin-releasing hormone. Our study describes the gut microbiome characteristics in thyroid nodules and a gut-thyroid link and highlight specific gut microbiota as a potential therapeutic target to regulate thyroid metabolism.

Thyroid Nodule Evaluation and Management in Older Adults: A Review of Practical Considerations for Clinical Endocrinologists

OBJECTIVE

Contextualizing the evaluation of older adults with thyroid nodules is necessary to fully understand which management strategy is the most appropriate. Our goal was to summarize available clinical evidence to provide guidance in the care of older adults with thyroid nodules and highlight special considerations for thyroid nodule evaluation and management in this population.

METHODS

We conducted a literature search of PubMed and Ovid MEDLINE from January 2000 to November 2020 to identify relevant peer-reviewed articles published in English. References from the included articles as well as articles identified by the authors were also reviewed.

RESULTS

The prevalence of thyroid nodules increases with age. Although thyroid nodules in older adults have a lower risk of malignancy, identified cancers are more likely to be of high-risk histology. The goals of thyroid nodule evaluation and the tools used for diagnosis are similar for older and younger patients with thyroid nodules. However, limited evidence exists regarding thyroid nodule evaluation and management to guide personalized decision making in the geriatric population.

CONCLUSION

Considering patient context is significant in the diagnosis and management of thyroid nodules in older adults. When making management decisions in this population, it is essential to carefully weigh the risks and benefits of thyroid nodule diagnosis and treatment, in view of older adults' higher prevalence of high-risk thyroid cancer as well as increased risk for multimorbidity, functional and cognitive decline, and treatment complications.

Thyroid nodules: diagnostic evaluation based on thyroid cancer risk assessment

Thyroid nodules are extremely common and can be detected by sensitive imaging in more than 60% of the general population. They are often identified in patients without symptoms who are undergoing evaluation for other medical complaints. Indiscriminate evaluation of thyroid nodules with thyroid biopsy could cause a harmful epidemic of diagnoses of thyroid cancer, but inadequate selection of thyroid nodules for biopsy can lead to missed diagnoses of clinically relevant thyroid cancer. Recent clinical guidelines advocate a more conservative approach in the evaluation of thyroid nodules based on risk assessment for thyroid cancer, as determined by clinical and ultrasound features to guide the need for biopsy. Moreover, newer evidence suggests that for patients with indeterminate thyroid biopsy results, a combined assessment including the initial ultrasound risk stratification or other ancillary testing (molecular markers, second opinion on thyroid cytology) can further clarify the risk of thyroid cancer and the management strategies. This review summarizes the clinical importance of adequate evaluation of thyroid nodules, focuses on the clinical evidence for diagnostic tests that can clarify the risk of thyroid cancer, and highlights the importance of considering the patient's values and preferences when deciding on management strategies in the setting of uncertainty about the risk of thyroid cancer.

Geographic influences in the global rise of thyroid cancer

The incidence of thyroid cancer is on the rise, and this disease is projected to become the fourth leading type of cancer across the globe. From 1990 to 2013, the global age-standardized incidence rate of thyroid cancer increased by 20%. This global rise in incidence has been attributed to several factors, including increased detection of early tumours, the elevated prevalence of modifiable individual risk factors (for example, obesity) and increased exposure to environmental risk factors (for example, iodine levels). In this Review, we explore proven and novel hypotheses for how modifiable risk factors and environmental exposures might be driving the worldwide increase in the incidence of thyroid cancer. Although overscreening and the increased diagnosis of possibly clinically insignificant disease might have a role in certain parts of the world, other areas could be experiencing a true increase in incidence due to elevated exposure risks. In the current era of personalized medicine, national and international registry data should be applied to identify populations who are at increased risk for the development of thyroid cancer.

Trace Element Levels in the Elders over 80 from the Hainan Province of China

Trace elements are key regulators of metabolism and physiological pathways, and their levels change during aging. Hair, as a biological sample, has attracted much attention due to its ease of collection and slow substance metabolism. Also, trace elements in hair can reveal the distribution of essential nutrients and toxic elements in the body pools. Therefore, we investigated the lifestyle and dietary status by questionnaire and measured 8 trace elements in hair and 6 elements in blood of a sample of elders over 80 residing in Hainan province of China. Our data showed that the concentration of Se, Fe and Pb dropped as people grow older, but Mn rose. Changes in trace elements may affect enzyme activity and biological pathways, and are associated with many diseases, including cancer and chronic diseases. In addition, association between age-related diseases and trace elements are increasingly being reported, suggesting that approaches of combining nutrition with longevity studies in the further study will help us to identify the mechanisms whereby trace elements affect the aging process.

Prevalence of functional dependence in Chinese centenarians and its relationship with serum vitamin D status

Background

Functional dependence (FD) and vitamin D deficiency are common conditions in older adults. However, little is known about the relationship between FD and serum vitamin D status in centenarians. The current study was designed to evaluate the prevalence of FD and examine its relationship with serum vitamin D status among centenarians in China.

Subjects and methods

A cross-sectional study of a large sample of Chinese centenarians including 180 men and 822 women was conducted from June 2014 to December 2016. Home interviews, physical examinations, and blood analyses were performed in 958 centenarians following standard procedures. FD was evaluated using the Barthel index of activities of daily living (ADL). Serum 25-hydroxyvitamin D (25OHD) concentrations were measured as a marker of vitamin D status.

Results

The prevalence of centenarians with FD was 71.2%. Vitamin D deficiency, lack of tea consumption, lack of outdoor activities, visual impairment, and fracture were predictors of FD. Centenarians in the lowest quartile of serum 25OHD concentration had an approximately threefold greater likelihood of FD than those in the highest quartile in multiple logistic regression models (OR =2.88; 95% CI 1.75–4.73; P<0.001). The multivariable OR with a 1 ng/mL decrease in serum 25OHD concentration was 1.06 (95% CI 1.04–1.08; P<0.001) for FD.

Conclusion

Serum 25OHD levels have important associations with FD in Chinese centenarians. Future research could focus on the value of intervening in the case of low serum 25OHD levels through vitamin D supplementation and improving ADL in the older population.