The 6th International Conference, “Controversies in Vitamin D,” was convened to discuss controversial topics, such as vitamin D metabolism, assessment, actions, and supplementation. Novel insights into vitamin D mechanisms of action suggest links with conditions that do not depend only on reduced solar exposure or diet intake and that can be detected with distinctive noncanonical vitamin D metabolites. Optimal 25-hydroxyvitamin D (25(OH)D) levels remain debated. Varying recommendations from different societies arise from evaluating different clinical or public health approaches. The lack of assay standardization also poses challenges in interpreting data from available studies, hindering rational data pooling and meta-analyses. Beyond the well-known skeletal features, interest in vitamin D's extraskeletal effects has led to clinical trials on cancer, cardiovascular risk, respiratory effects, autoimmune diseases, diabetes, and mortality. The initial negative results are likely due to enrollment of vitamin D-replete individuals. Subsequent post hoc analyses have suggested, nevertheless, potential benefits in reducing cancer incidence, autoimmune diseases, cardiovascular events, and diabetes. Oral administration of vitamin D is the preferred route. Parenteral administration is reserved for specific clinical situations. Cholecalciferol is favored due to safety and minimal monitoring requirements. Calcifediol may be used in certain conditions, while calcitriol should be limited to specific disorders in which the active metabolite is not readily produced in vivo. Further studies are needed to investigate vitamin D effects in relation to the different recommended 25(OH)D levels and the efficacy of the different supplementary formulations in achieving biochemical and clinical outcomes within the multifaced skeletal and extraskeletal potential effects of vitamin D.

Hypoparathyroidism (HypoPT) is a rare (orphan) endocrine disease with low calcium and inappropriately low (insufficient) circulating parathyroid hormone levels, most often in adults secondary to thyroid surgery. Standard treatment is activated vitamin D analogues and calcium supplementation and not replacement of the lacking hormone, as in other hormonal deficiency states. The purpose of this guideline is to provide clinicians with guidance on the treatment and monitoring of chronic HypoPT in adults who do not have end-stage renal disease. We intend to draft a practical guideline, focusing on operationalized recommendations deemed to be useful in the daily management of patients. This guideline was developed and solely sponsored byThe European Society of Endocrinology, supported by CBO (Dutch Institute for Health Care Improvement) and based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) principles as a methodological base. The clinical question on which the systematic literature search was based and for which available evidence was synthesized was: what is the best treatment for adult patients with chronic HypoPT? This systematic search found 1100 articles, which was reduced to 312 based on title and The working group assessed these for eligibility in more detail, and 32 full-text articles were assessed. For the final recommendations, other literature was also taken into account. Little evidence is available on how best to treat HypoPT. Data on quality of life and the risk of complications have just started to emerge, and clinical trials on how to optimize therapy are essentially non-existent. Most studies are of limited sample size, hampering firm conclusions. No studies are available relating target calcium levels with clinically relevant endpoints. Hence it is not possible to formulate recommendations based on strict evidence. This guideline is therefore mainly based on how patients are managed in clinical practice, as reported in small case series and based on the experiences of the authors.

Context: The clinical presentation of primary hyperparathyroidism (pHPT) has changed during the last half century, and the diagnosis is now more often made by chance in patients with no specific symptoms. Objective: The present study is a randomized, controlled trial that investigates the effects of parathyroidectomy or medical observation in mild asymptomatic pHPT on morbidity and quality of life (QoL). Design/Setting/Patients: A total of 191 patients (26 men) with asymptomatic pHPT [mean age 64.2 ± 7.4 (sd) yr] were recruited in the study and randomized to medical observation (serum calcium level 2.69 ± 0.08 mmol/liter) or surgery (2.70 ± 0.08 mmol/liter). We here report baseline and 1 (n = 119) and 2 yr data (n = 99) on those who had completed the follow-up visits by the end of the inclusion period. Results: At baseline, the patients had significantly lower QoL (SF-36) and more psychological symptoms, compared with age- and sex-matched healthy subjects. The two groups were similar at baseline, and no clinically significant changes in these parameters were seen during the observation time. Calcium and PTH normalized after surgery. The areal bone mineral density increased in the group randomized to operation, whereas the bone mineral density remained stable in the medical observation group. No change in kidney function (creatinine) or blood pressure was observed longitudinally or between the groups. Conclusions: Asymptomatic patients with mild pHPT have decreased QoL and more psychological symptoms than normal controls. No benefit of operative treatment, compared with medical observation, was found on these measures so far.

This European expert consensus statement provides recommendations for the diagnosis and management of primary hyperparathyroidism (PHPT), chronic hypoparathyroidism in adults (HypoPT), and parathyroid disorders in relation to pregnancy and lactation. Specified areas of interest and unmet needs identified by experts at the second ESE Educational Program of Parathyroid Disorders in 2019 were discussed during two virtual workshops in 2021 and subsequently developed by working groups with interest in the specified areas. PHPT is a common endocrine disease. However, its differential diagnosis of familial hypocalciuric hypercalcemia (FHH), the definition and clinical course of normocalcemic PHPT, and the optimal management of its recurrence after surgery represents areas of uncertainty requiring clarifications. HypoPT is an orphan disease characterized by low calcium concentrations due to insufficient PTH secretion, most often secondary to neck surgery. Prevention and prediction of surgical injury to the parathyroid glands are essential to limit the disease-related burden. Long-term treatment modalities including the place for PTH replacement therapy and the optimal biochemical monitoring and imaging surveillance for complications to treatment in chronic HypoPT need to be refined. The physiological changes in calcium metabolism occurring during pregnancy and lactation modify the clinical presentation and management of parathyroid disorders in these periods of life. Modern interdisciplinary approaches to PHPT and HypoPT in pregnant and lactating women and their newborn children are proposed. The recommendations on clinical management presented here will serve as background for further educational material aimed at a broader clinical audience and were developed with the focus on endocrinologists in training.

The prevalence of vitamin D insufficiency and secondary hyperparathyroidism is high among morbidly obese subjects. Further, low serum levels of 25-hydroxyvitamin D (25 [OH]D) and magnesium have been associated with increased risk of the metabolic syndrome (MS), and recently, a possible link between PTH and MS has been reported. Although it is well known that the synthesis and secretion of PTH is regulated by serum levels of calcium, phosphate, magnesium and 25(OH)D, less is known about the possible clustered affiliation of these parameters with MS. We aimed to explore whether MS is associated with abnormal serum levels of PTH, 25(OH)D and magnesium in a population of morbidly obese patients.