Vitamin D and malabsorptive gastrointestinal conditions: A bidirectional relationship?

This paper is one of the outcomes of the 5th International Conference "Controversies in Vitamin D" held in Stresa, Italy from 15 to 18 September 2021 as part of a series of annual meetings which was started in 2017. The scope of these meetings is to discuss controversial issues about vitamin D. Publication of the outcomes of the meeting in international journals allows a wide sharing of the most recent data with the medical and academic community. Vitamin D and malabsorptive gastrointestinal conditions was one of the topics discussed at the meeting and focus of this paper. Participants to the meeting were invited to review available literature on selected issues related to vitamin D and gastrointestinal system and to present their topic to all participants with the aim to initiate a discussion on the main outcomes of which are reported in this document. The presentations were focused on the possible bidirectional relationship between vitamin D and gastrointestinal malabsorptive conditions such as celiac disease, inflammatory bowel diseases (IBDs) and bariatric surgery. In fact, on one hand the impact of these conditions on vitamin D status was examined and on the other hand the possible role of hypovitaminosis D on pathophysiology and clinical course of these conditions was also evaluated. All examined malabsorptive conditions severely impair vitamin D status. Since vitamin D has known positive effects on bone this in turn may contribute to negative skeletal outcomes including reduced bone mineral density, and increased risk of fracture which may be mitigated by vitamin D supplementation. Due to the immune and metabolic extra-skeletal effects there is the possibility that low levels of vitamin D may negatively impact on the underlying gastrointestinal conditions worsening its clinical course or counteracting the effect of treatment. Therefore, vitamin D status assessment and supplementation should be routinely considered in all patients affected by these conditions. This concept is strengthened by the existence of a possible bidirectional relationship through which poor vitamin D status may negatively impact on clinical course of underlying disease. Sufficient elements are available to estimate the desired threshold vitamin D level above which a favourable impact on the skeleton in these conditions may be obtained. On the other hand, ad hoc controlled clinical trials are needed to better define this threshold for obtaining a positive effect of vitamin D supplementation on occurrence and clinical course of malabsorptive gastrointestinal diseases.

Modern approach to resistant acromegaly.

BACKGROUND: Targets of acromegaly treatment are normalization of biochemical values, removal/reduction/stabilization of the pituitary mass, control of clinical activity and mortality with a multimodal/multidisciplinary approach. Despite significant technological and pharmacological progress, still several patients with acromegaly bear a resistant somatotroph adenoma and active disease may persist for many years with resultant poor clinical outcomes. AIM: To review briefly definition and pathophysiology of resistance to acromegaly treatment and the options of medical treatment in this context, exploring the role of novel clinical and molecular biomarkers in the personalization of therapy and proposing updates to the currently available guidelines for the treatment of resistant GH-secreting adenomas. CONCLUSIONS: In the last few years, in parallel with the increased number of medical options available for the therapy of acromegaly, relevant advances occurred in the understanding of the role of novel molecular and clinical biomarkers in predicting the responsiveness to second-line medical treatments, such as Pegvisomant and Pasireotide LAR, and helping clinicians in the personalization of the follow-up and treatment of resistant somatotroph adenomas. The integration of these findings into the existing guidelines may represent a possibly important step forward in the management of "difficult" acromegaly patients.

Clinical Impact of Glucagon-Like Peptide-1 Receptor Analogs on the Complications of Obesity.

BACKGROUND: Obesity is a chronic disease associated with increased morbidity and mortality due to its complications. The aims of obesity treatment are primarily to accomplish weight loss, and prevention or treatment of its complications. Lifestyle changes along with behavioral therapy constitute the first-line treatment of obesity followed by pharmacotherapy. Glucagon-like peptide receptor analogs (GLP-1 RAs) are among the approved pharmacotherapy options. Their central effect on suppressing appetite results in considerable weight loss. However, their effect on the complications of obesity has not been very well recognized. This review aims to analyze the effects of GLP-1 RAs on the complications of obesity, as diabetes mellitus, hypertension, nonalcoholic steatohepatitis (NASH), cardiovascular diseases, polycystic ovary syndrome, infertility, obstructive sleep apnea (OSA), osteoarthritis, cancer and central nervous system problems. SUMMARY: Data from preclinical studies and clinical trials have been thoroughly evaluated. Effects regarding the complications as far as the scope of this review have covered can be summarized as blood glucose lowering, blood pressure lowering, resolution of NASH, improving major cardiovascular events, improving fertility and sex hormone levels, and improvement in OSA symptoms and in cognitive scores. Although the mechanisms are not fully elucidated, it is clear that the effects are not solely due to weight loss, but some pleiotropic effects like decreased inflammation, oxidative stress, and fibrosis also play a role in some of the complications. KEY MESSAGES: Treating obesity is not only enabling weight loss but ameliorating complications related to obesity. Thus, any antiobesity medication has to have some favorable effects on the complications. As far as the GLP-RA's analogs are concerned, there seems to be an improvement in many of the complications regardless of the weight loss effect of these medications.

Low vitamin D levels predict outcomes of COVID-19 in patients with both severe and non-severe disease at hospitalization.

PURPOSE: Low vitamin D in COVID-19 have been related to worse outcomes. However, most of the studies conducted so far were not-controlled and retrospective, including biases potentially influencing this association. We evaluated 25(OH)vitamin D levels of patients with both severe and non-severe disease at hospital-admission, and in a cohort of control subjects. Moreover, we evaluated sACE-2 levels to investigate the mechanisms underlying the association between vitamin D and COVID-19. METHODS: COVID-19 patients were enrolled in a matched for age, sex and comorbidities 1:1-ratio based on the presence/or not of respiratory-distress/severe-disease at hospital-admission. Control matched subjects were enrolled from an outpatient-setting. RESULTS: Seventy-three COVID-19 patients (36 severe and 37 non-severe) and 30 control subjects were included. We observed a higher vitamin D deficiency (<20 ng/mL) prevalence in COVID-19 patients than control subjects (75% vs 43%). No differences were found regarding 25(OH)vitamin D and sACE-2 levels between patients with and without severe-disease at study entry. During the disease-course, in the severe group a life-threatening disease occurred in 17 patients (47.2%), and, in the non-severe group, a worsening disease occurred in 10 (27%). 25(OH)vitamin D levels, at admission, were negatively correlated with sACE-2 levels, and were lower in patients whose disease worsened as compared to those in whom it did not, independently from the disease severity at admission. In multivariate-analysis, lower 25(OH)vitamin D resulted as an independent risk factor for disease worsening. CONCLUSIONS: 25(OH)vitamin D levels at hospital-admission strongly predicted the occurrence of worsening outcomes in COVID-19 independently of the disease severity at presentation.

Clinical and demographic aspects of Paget disease of bone: A multicentric study from Turkey.

OBJECTIVE: Paget disease of bone (PDB) is a metabolic bone disease that has been rarely reported in the Eastern countries. This study aimed to evaluate the clinical and demographic characteristics of patients with PDB followed up at endocrinology clinics in Turkey. METHODS: An invitation was sent to tertiary endocrinology clinics to complete a survey on the demographic, clinical, radiological, and laboratory parameters, as well as treatment modalities of patients with PDB. This study enrolled clinically and radiologically proven 185 patients with PDB from 18 endocrinology centers based in 10 cities of Turkey. RESULTS: This cohort of PDB had female preponderance (women/men: 105/80) with a mean age, during diagnosis, of 57±10 years. Most of the patients (59.6%) were symptomatic at diagnosis. Bone pain and headache were the predominant clinical symptoms. Polyostotic disease was observed in 67.5% (n=125) of patients. Frequently affected bones were skull (41.6%), pelvis (53.5%), spine (41%), and femur (25.4%). Moreover, 17 patients with skull involvement had hearing loss. Mean serum alkaline phosphatase (ALP) level (552±652 IU/L; range: 280-5762 IU/L) was over the normal reference cutoff with normal serum calcium levels. Intravenous bisphosphonates (zoledronic acid, 5 mg; pamidronate, 60-90 mg) were the most used drugs (75%) for the treatment of PDB. Most of the patients (87.1%) treated with intravenous bisphosphonates responded well, with a decrease in serum ALP level (117±114 IU/L) in the 12th month of therapy. Furthermore, 16 patients relapsed after the second year of therapy; 3 patients did not respond to the initial intravenous bisphosphonate treatment. CONCLUSION: The patients with PDB followed up by endocrinology clinics of Turkey exhibited polyostotic disease with classical clinical, radiological, and biochemical features and women's predominance with good response to intravenous bisphosphonate therapy.

Out-of-Reference Range Thyroid-Stimulating Hormone Levels in Levothyroxine-Treated Primary Hypothyroid Patients: A Multicenter Observational Study.

OBJECTIVE: Although levothyroxine (LT4) replacement therapy for hypothyroidism has been established as safe, inexpensive and effective, many studies from different countries reported out-of-reference range thyroid-stimulating hormone (TSH) values for the hypothyroid patients under LT4 treatment. The aim of this study was to determine TSH levels of primary hypothyroid patients under LT4 treatment and to assess self-reported compliance with daily LT4 intake in tertiary care centers in Turkey. DESIGN: In this cross-sectional, observational study, adult patients with primary hypothyroidism, receiving LT4 treatment for at least 6 months, were included. The patients were from 12 tertiary care centers in 9 cities of Turkey. TSH and free T4 levels were recorded from patient files and self-reported compliance with daily LT4 intake was assessed by interviewing the subjects at the last visit. RESULTS: A total of 1,755 subjects (46 ± 13 years; F/M: 89.9/10.1%) with primary hypothyroidism were enrolled. Of the hypothyroid subjects, 44.8% had out-of-reference range serum TSH levels. TSH values were over the reference range (TSH > 4 mIU/L) in 26.2% and were under the reference range (TSH < 0.5 mIU/L) in 18.6% of the patients. Total duration of LT4 treatment was 5.9 ± 4.7 years and mean dose was 1.2 ± 0.6 µg/kg/day. Non-compliant patients (31.1%) had higher TSH levels (6.9 ± 16 vs 3.8 ± 0.9 mIU/L, P = 0.01) compared to compliant patients. CONCLUSION: The results of this study revealed that nearly half of the hypothyroid patients had out-of-reference range serum TSH values, despite under LT4 treatment. Compliance with LT4 treatment seems to be one of the major determinants to reach the target TSH levels in hypothyroid patients.