International Journal of Endocrinology and Metabolism最新文献

The progressive development of clinical and public health nutrition has long relied on dietary clinical trials (DCTs), investigating the causal relationship between diet and multiple risk factors of non-communicable and chronic diseases. DCTs are also hallmarks for establishing dietary requirements and promoting overall nutritional health among the population. Despite their critical importance in translation into public health strategies and practices, DCTs have several limitations and challenges for study design, implementation and finding interpretation. The complex nature of nutrition interventions, collinearity between diet components, multi-target effects of the interventions, diverse dietary behaviors, and food culture are the most challenging issues. Furthermore, baseline exposure and dietary status, appropriate control groups, blinding, randomization, and poor adherence undermine the effectiveness of DCTs in translation into practices. Disruptive factors will be minimized if researchers are committed to following good clinical practice (GCP) standards available for common designs of clinical trials. Planning DCTs, however, needs careful considerations for hypothesis generation, study design development, the definition of primary and secondary outcome measures, and target population.

Context: The important role of physical activity in the prevention and management of diabetes necessitates a review of current research to shed light on gaps in national diabetes guidelines.

Evidence acquisition: This scoping review was part of the Iran Diabetes Research Roadmap (IDRR) study. A systematic search was used based on the Arksey and O'Malley method consisting of six steps. The descriptive analysis was done with SPSS software. Additionally, VOS veiwer software was used to draw the knowledge map of the included studies.

Results: There were 169 articles included from the beginning of 2015 to the end of 2019 in Iran. Aerobic and resistance exercises were types of physical activity with more number of articles. Most of the included clinical studies were randomized clinical trials and had a level of evidence two. Also, there was more interest in outcomes such as glycemic control and insulin sensitivity, metabolic syndrome, metabolism, and cardiovascular health. The network of co-authorship was drawn, and "controlled study", "male", and "rat" were the most frequent keywords.

Conclusions: The number of Iranian diabetes researchers on physical activity is increasing, and the majority of clinical studies had a high level of evidence. With maintaining previous interests and investigations, there should be more emphasis on research in elderly and children age groups as evidence gap in Iran. Also, longitudinal cohort studies should be highlighted and Iranian researchers should be encouraged to participate in new topics of research worldwide.

Context: Growing evidence highlights the importance of physical activity as a critical element for the prevention and control of diabetes. However, there is no clinical practice guideline focusing on the different aspects of exercise in patients with diabetes, especially for the Iranian population.

Objective: We aimed to prepare and adopt a clinical practice guideline to provide well-defined, simple, and concise responses to certain questions related to physical activity and exercise in all patients with diabetes, including type 1, 2, and gestational diabetes mellitus (GDM).

Evidence acquisition: A multidisciplinary team of experts in various fields (sports medicine specialists, endocrinologists, and cardiologists) developed the guideline. This group did the task in four stages: (1) identifying and refining the subject area using 17 clinical questions; (2) appraising evidence through a systematic review of the literature; (3) extracting recommendations from evidence and grading them as A, B, C, or D based on the quality, quantity, and consistency of existing evidence; and (4) subjecting the guideline to external review and finally selecting the recommendations with high scores of appropriateness and agreement. The final version was evaluated and approved by the National Deputy for Curative Affairs - Ministry of Health and Medical Education and has also been endorsed by the Iran Endocrine Society (IES) and Iranian Association of Sports and Exercise Medicine (IASEM).

Results: The guideline consists of 52 recommendations addressing 17 important questions concerning different aspects of exercise prescription in Iranian patients with diabetes.

Conclusions: The guideline provides evidence-based information that may help physicians to prescribe exercise for Iranian patients with diabetes safely and effectively.

Introduction: The art of medicine glorifies when a clinician listens carefully to the patient's story, gives a thorough examination, performs appropriate investigations, and finally links findings together to reach a definite diagnosis. An interesting case was reported here, highlighting the integration of different symptoms and manifestations with some relevant biochemical investigations to reach a final diagnosis. To the best of our knowledge, fixed flexion deformity, as a complication of subcutaneous calcification, has not been previously reported in a child with Albright hereditary osteodystrophy (AHO).

Case presentation: A 2.5-year-old boy was born at term with a birth weight of 3.5 kg (-0.49 SDS). The child was referred to a general pediatrician with a history of right elbow joint swelling noticed initially at six months of age. He then developed the limitation of right upper arm movement, which slowly progressed afterward. The patient had no history of trauma. At nine months of age, he was diagnosed with hypothyroidism, preceded by cold skin, dry hair, and constipation. At nine years of age, he presented with a fixed flexion deformity of the right elbow associated with markedly limited joint movement and symmetrical hands with hyperpigmented knuckles of right metacarpal bones. Subcutaneous masses were felt along the right forearm, showing tenderness on palpation. Investigations revealed elevated serum parathyroid hormone and normal calcium indicating parathyroid hormone resistance. Further genetic testing revealed GNAS mutation. The child was obese throughout his childhood.

Conclusions: This case report describes an obese child with subcutaneous calcification that led to fixed flexion deformity of the elbow, starting at an incredibly early age. Hypothyroidism and pseudohypoparathyroidism raised the suspicion of AHO, which was later confirmed by genetic testing. This is the first case report on fixed flexion deformity in a patient with GNAS mutation (c.719-1G > A Chr20: 57484737) in West Asia.

Background: Further studies are needed to extend our knowledge about the association between male infertility and cardio-metabolic disorders.

Objectives: We aimed to assess the association between male infertility and cardiometabolic disturbances using a population-based design.

Methods: In total, 1611 participants of the Tehran-Lipid and Glucose-Study (phase III) were categorized into two groups of men with documented male infertility (n = 88) and those with at least one live birth and no history of primary infertility (n = 1523). Logistic regression was applied to explore the association between male infertility and cardiometabolic disturbances, including diabetes mellitus, pre-diabetes, hypertension, metabolic syndrome, dyslipidemia, obesity, central obesity, and chronic kidney disease, following adjustment for age and body mass index (BMI).

Results: The unadjusted model revealed a significant association between infertility and hypertension and CKD (OR = 1.8; 95% CI: 1.2, 2.9, P-value = 0.006 and OR = 1.9; 95% CI: 1.1, 3.6, P-value = 0.033), respectively. However, after adjusting for age and BMI, as potential confounders, this association was not significant. Moreover, there was no association between infertility and other cardiometabolic disturbances, including diabetes and pre-diabetes, metabolic syndrome, dyslipidemia, obesity, and central obesity in both unadjusted and adjusted models.

Conclusions: Our study revealed no association between male infertility and cardiometabolic disturbances. The findings can pave the way for further studies to extend our knowledge in this field. More population-based studies with a large sample size are warranted to confirm these findings.

Background: Nitric oxide (NO) plays a key role in thyroid function regulation through the inhibition of iodide (I) uptake at the thyroidal sodium-iodide symporter (NIS) and impacts on the thyroid vascularity and blood flow.

Objectives: This study aimed to evaluate the association between serum NO metabolites (NOx) and thyroid-stimulating hormone (TSH), free thyroxin (FT4), and anti-thyroid peroxidase (TPOAb) changes. Also, it aimed at evaluating the correlation between serum NOx and the incidence of clinical hypothyroidism, characterized by elevated TSH level and decreased FT4 concentration, and subclinical hypothyroidism, characterized by mildly elevated TSH level despite FT4 concentration within the normal range, over three years of follow-up.

Methods: This study included 1,137 participants of the Tehran Thyroid study (TTS), aged > 20 years old, for whom data on serum TSH, FT4, and TPOAb in the third and fourth phases, and serum NOx in the third phase were available. Changes in TSH (ΔTSH), FT4 (ΔFT4), and TPOAb (ΔTPO) between the third and fourth phases were calculated, and the associations between serum NOx and ΔTSH, ΔFT4, and ΔTPOAb were assessed after multivariable adjustment using linear regression analysis.

Results: No significant association was found between serum NOx and ΔTSH, ΔFT4, and ΔTPOAb after the multivariable adjustment; neither was any observed in TPOAb split groups after multivariable adjustment. No significant association was found between serum NOx tertiles and clinical and subclinical hypothyroidism incidence in the fourth phase of TTS.

Conclusions: There was no association between serum NOx levels and changes in TSH, FT4, and TPOAb and clinical and subclinical hypothyroidism incidence.

Objectives: This study aimed to provide an overview of prediction models of undiagnosed type 2 diabetes mellitus (U-T2DM) or the incident T2DM (I-T2DM) using the transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) checklist and the prediction model risk of the bias assessment tool (PROBAST).

Data sources: Both PUBMED and EMBASE databases were searched to guarantee adequate and efficient coverage.

Study selection: Articles published between December 2011 and October 2019 were considered.

Data extraction: For each article, information on model development requirements, discrimination measures, calibration, overall performance, clinical usefulness, overfitting, and risk of bias (ROB) was reported.

Results: The median (interquartile range; IQR) number of the 46 study populations for model development was 5711 (1971 - 27426) and 2457 (2060 - 6995) individuals for I-T2DM and U-T2DM, respectively. The most common reported predictors were age and body mass index, and only the Qrisk-2017 study included social factors (e.g., Townsend score). Univariable analysis was reported in 46% of the studies, and the variable selection procedure was not clear in 17.4% of them. Moreover, internal and external validation was reported in 43% the studies, while over 63% of them reported calibration. The median (IQR) of AUC for I-T2DM models was 0.78 (0.74 - 0.82); the corresponding value for studies derived before October 2011 was 0.80 (0.77 - 0.83). The highest discrimination index was reported for Qrisk-2017 with C-statistics of 0.89 for women and 0.87 for men. Low ROB for I-T2DM and U-T2DM was assessed at 18% and 41%, respectively.

Conclusions: Among prediction models, an intermediate to poor quality was reassessed in several aspects of model development and validation. Generally, despite its new risk factors or new methodological aspects, the newly developed model did not increase our capability in screening/predicting T2DM, mainly in the analysis part. It was due to the lack of external validation of the prediction models.

Background: Chronic kidney disease (CKD) is a rising public health concern that has detrimental effects on cardiovascular health and overall survival. Subclinical hypothyroidism (SCH) has been associated with poor outcomes in the general population. It is thought to be more prevalent in CKD subjects, and their coexistence may contribute to poor outcomes in these patients. We aimed to determine the prevalence of SCH in CKD.

Methods: Using data from the Tehran thyroid study, which is a prospective population-based cohort study, adult subjects with an estimated Glomerular Filtration Rate (eGFR) of 60 mL/min/1.73 m² or less were selected for studying the prevalence of thyroid abnormalities, as well as other known cardiovascular risk factors.

Results: Of 5,626 subjects recruited, 823 (14.6%) individuals had CKD. Individuals with CKD were older, heavier, had a higher prevalence of diabetes, higher serum thyrotropin, and thyroid peroxidase anti-body levels, but lower free thyroxine levels. The prevalence of SCH was 7.3% and 5.2% (P < 0.001) in kidney disease and non-kidney disease subjects, respectively. However, there was no difference in the risk of SCH between CKD and non-CKD subjects after adjustment for age, sex, BMI, smoking, and TPOAb (OR: 1.28; 95%CI, 0.89 - 1.83). None of the metabolic markers compared between the CKD subgroups of those with and without SCH remained statistically significantly different after adjusting for age and gender.

Conclusions: The prevalence of SCH was not higher in CKD after controlling for confounding factors. Besides, CKD subjects with and without SCH had no different metabolic parameters.

Background: Von Hippel Lindau (VHL) disease is a hereditary disorder characterized by the development of benign or malignant tumors in the brain, spinal cord, eyes, adrenal medulla, kidney, pancreas, and many other organs. Advances in molecular diagnosis have led to the identification of the affected members of families at earlier stages. We present the clinical, laboratory, and genetic characteristics of five generations of a large Iranian kindred with VHL.

Methods: The proband, a 52-year-old Iranian man, was recognized with VHL. All family members underwent clinical, laboratory, imaging, and genetic evaluation. Medical files and histopathology reports of patients who had been operated on before were also reviewed. Diagnosis of the disease was based on clinical findings, positive family history of VHL, and development of a central nervous system or retinal hemangioblastoma or pheochromocytoma.

Results: Based on diagnostic criteria, our initial evaluations revealed that 10 members of the family had already been affected by the disease. Among them, nine had pheochromocytoma, and one had retinal hemangioblastoma. There was no case of kidney tumors among the kindred.

Conclusions: Study results show the high penetrance of the disease and focus on the large burden imposed by the disease on the health and quality of life of patients afflicted with the disease, emphasizing the importance of surveillance from early childhood for detection and management of the disease as early as possible.