Coincident diabetes mellitus and primary hyperparathyroidism

Higher risk of incident diabetes among patients with primary hyperparathyroidism

OBJECTIVES

There is relatively scarce data regarding the association between primary hyperparathyroidism (PHPT) and incident diabetes in large population-based longitudinal studies. We aimed to evaluate the risk of incident diabetes in individuals with and without PHPT and investigate the association between serum calcium concentrations and the risk of incident diabetes in patients with PHPT.

METHODS

We included 2749 PHPT patients and 13,745 age, sex and index year matched non-PHPT individuals during 2000-2019. We used Cox regression models to compare the risk of incident diabetes in individuals with and without PHPT, and the risk of incident diabetes in PHPT patients with serum calcium concentration above and below the median value. The association between serum calcium concentrations and the risk of incident diabetes was examined by restricted cubic spline analyses in patients with PHPT.

RESULTS

During a median follow-up time of 5.17 years (IQR 2.17, 9.58), 433 patients (15.75%) with PHPT and 2110 individuals (15.35%) without PHPT developed diabetes, respectively. Patients with PHPT had a higher incidence rate of diabetes compared to non-PHPT individuals (27.60 [95% CI 25.00, 30.30] vs. 23.90 [95% CI 22.80, 24.90] per 1000 person-years, log-rank test p = .007]. Crude Cox regression model showed PHPT was associated with a 15% higher risk of incident diabetes (HR 1.15, 95%CI 1.04, 1.28). In patients with PHPT, a 44% higher risk of incident diabetes was found in patients with serum calcium concentrations above the median value (2.63 mmol/L), compared to those below the median value (HR 1.44, 95%CI 1.08, 1.90). Restricted cubic spline analyses confirmed a positive linear association between serum calcium concentrations and the risk of incident diabetes in those with PHPT (p-value for nonlinear = .751) CONCLUSIONS: Patients with PHPT had a higher risk of incident diabetes compared to non-PHPT individuals. A positive linear association was found between serum calcium concentrations and the risk of incident diabetes in patients with PHPT.

Primary Hyperparathyroidism and Cardiovascular Disease: An Association Study Using Clinical Natural Language Processing Systems and Big Data Analytics

Primary hyperparathyroidism (PHPT) seems to be associated with different cardiovascular diseases (CVDs). We evaluated the association of PHPT with major CV risk factors (CVRFs) and CVDs by using artificial intelligence (AI) tools. An observational and retrospective study was conducted using data from the electronic health records (EHRs) of the Hospital Universitario Puerta de Hierro Majadahonda (Spain). Of a total of 699,157 patients over 18 years of age studied (54.7% females), 6515 patients (0.9%; 65.4% women; mean age 67.6 ± 15.9 years) had a diagnosis of PHPT. The overall frequencies of hypertension, dyslipidemia, diabetes mellitus, and smoking habit in the cohort of patients with PTHP were all significantly (p < 0.001) higher than those found in patients without a diagnosis of PTHP. The total frequency of stroke, ischemic heart disease, atrial fibrillation, deep vein thrombosis, and pulmonary embolism in the cohort of PHPT patients were significantly (p < 0.001) higher than that found in patients without the diagnosis of PHPT. A multivariate regression analysis showed that PHPT was significantly (p < 0.001) and independently associated with all the CVDs evaluated. Our data show that there is a significant association between the diagnosis of PHPT and the main CVRFs and CVDs in our hospital population.

Association Between Primary Hyperparathyroidism and Secondary Diabetes Mellitus: Findings From a Scoping Review

An ill-defined association exists between diabetes mellitus (insulin resistance) and primary hyperparathyroidism. This article explores this phenomenon while providing an explanation for such a relationship and reviewing the evidence regarding the response to insulin sensitivity following a parathyroidectomy. Primary hyperparathyroidism may increase the risk of developing insulin resistance; peculiarly, this is not present in all patients. It is likely that both intracellular hypercalcemia and hypophosphatemia alter the insulin receptor expression and response; the contribution of parathyroid hormone is less clear. Following parathyroidectomy, patients may demonstrate improvement in their insulin sensitivity, while others have no response or a detrimental effect. A varied phenotype exists among patients, and furthermore, it is unclear why certain patients demonstrate improvement in insulin sensitivity following a parathyroidectomy, whereas others fail to do so. While this review provides a broad overview of the general endocrine community, it is imperative to note that clinical applicability is limited until further studies address these remaining uncertainties. Due to the lack of understanding regarding this endocrinological enigma, the presence of insulin resistance, at this present time, should not be a criterion for a parathyroidectomy.

Mortality and Morbidity in Mild Primary Hyperparathyroidism: Results From a 10-Year Prospective Randomized Controlled Trial of Parathyroidectomy Versus Observation

BACKGROUND

Primary hyperparathyroidism (PHPT) is a common endocrine disorder associated with increased risk for fractures, cardiovascular disease, kidney disease, and cancer and increased mortality. In mild PHPT with modest hypercalcemia and without known morbidities, parathyroidectomy (PTX) is debated because no long-term randomized trials have been performed.

OBJECTIVE

To examine the effect of PTX on mild PHPT with regard to mortality (primary end point) and key morbidities (secondary end point).

DESIGN

Prospective randomized controlled trial. (ClinicalTrials.gov: NCT00522028).

SETTING

Eight Scandinavian referral centers.

PATIENTS

From 1998 to 2005, 191 patients with mild PHPT were included.

INTERVENTION

Ninety-five patients were randomly assigned to PTX, and 96 were assigned to observation without intervention (OBS).

MEASUREMENTS

Date and causes of death were obtained from the Swedish and Norwegian Cause of Death Registries 10 years after randomization and after an extended observation period lasting until 2018. Morbidity events were prospectively registered annually.

RESULTS

After 10 years, 15 patients had died (8 in the PTX group and 7 in the OBS group). Within the extended observation period, 44 deaths occurred, which were evenly distributed between groups (24 in the PTX group and 20 in the OBS group). A total of 101 morbidity events (cardiovascular events, cerebrovascular events, cancer, peripheral fractures, and renal stones) were also similarly distributed between groups (52 in the PTX group and 49 in the OBS group). During the study, a total of 16 vertebral fractures occurred in 14 patients (7 in each group).

LIMITATION

During the study period, 23 patients in the PTX group and 27 in the OBS group withdrew.

CONCLUSION

Parathyroidectomy does not appear to reduce morbidity or mortality in mild PHPT. Thus, no evidence of adverse effects of observation was seen for at least a decade with respect to mortality, fractures, cancer, cardiovascular and cerebrovascular events, or renal morbidities.

PRIMARY FUNDING SOURCE

Swedish government, Norwegian Research Council, and South-Eastern Norway Regional Health Authority.

Assessment of insulin resistance in patients with primary hyperparathyroidism before and after Parathyroidectomy

Background

Primary hyperparathyroidism (PHPT) can lead to renal and skeletal disorders, as well as insulin resistance and impaired glucose metabolism. The current study aimed to assess the effects of parathyroidectomy on insulin resistance in patients with PHPT.

Materials and Methods

The present study was conducted on 65 patients with PHPT and indications for parathyroidectomy who were referred to the endocrinology clinics of Mashhad University of Medical Sciences. Thereafter, the demographic characteristics of the patients were recorded. Blood tests, including haemoglobin A1c (HbA1c), fasting blood glucose (FBG) and insulin levels, were assessed one week before and three months after the surgery. The insulin resistance score (HOMA‐IR) was calculated and compared using the relevant formula.

Results

A total of 65 participants with a mean age of 45.44 ± 9.59 years were included in the current study. In one‐month postoperative tests, mean scores of FBG (p < .05), insulin level (p < .05) and HbA1c (p < .05) were significantly reduced. Moreover, the HOMA‐IR index decreased in 51 patients after the surgery.

Conclusion

According to our findings, parathyroidectomy can be effective in the reduction of insulin resistance and corresponding complications in patients with PHPT in the present short‐term study. However, it has yet to be confirmed as a treatment method for insulin resistance in these patients. Future long‐term studies are required to be done to investigate the effect of parathyroidectomy on insulin resistance.

The present study aimed to assess the effects of parathyroidectomy on insulin resistance in patients with primary hyperparathyroidism (PHPT). The present study was conducted on 65 patients with PHPT and indications for parathyroidectomy. Demographic characteristics of the patients were recorded. Blood tests, including fasting blood sugar (FBS), haemoglobin A1c (HbA1c) and insulin levels, were assessed one week before and three months after the surgery. The Homeostatic Model Assessment for Insulin Resistance (HOMA‐IR index) was calculated. In one‐month postoperative tests, mean scores of FBS (p < .05), insulin level (p < .05) and HbA1c (p < 0.05) were significantly reduced compared to these variables prior to the surgery. Moreover, the HOMA‐IR index decreased in 51 patients after the surgery. As evidenced by the results of the present study, parathyroidectomy can be effective in reducing insulin resistance and its complications in patients with primary hyperparathyroidism (PHPT).

The Impact of Antiosteoporotic Drugs on Glucose Metabolism and Fracture Risk in Diabetes: Good or Bad News?

Osteoporosis and diabetes mellitus represent global health problems due to their high, and increasing with aging, prevalence in the general population. Osteoporosis can be successfully treated with both antiresorptive and anabolic drugs. While these drugs are clearly effective in reducing the risk of fracture in patients with postmenopausal and male osteoporosis, it is still unclear whether they may have the same efficacy in patients with diabetic osteopathy. Furthermore, as bone-derived cytokines (osteokines) are able to influence glucose metabolism, it is conceivable that antiosteoporotic drugs may have an effect on glycemic control through their modulation of bone turnover that affects the osteokines’ release. These aspects are addressed in this narrative review by means of an unrestricted computerized literature search in the PubMed database. Our findings indicate a balance between good and bad news. Active bone therapies and their modulation of bone turnover do not appear to play a clinically significant role in glucose metabolism in humans. Moreover, there are insufficient data to clarify whether there are any differences in the efficacy of antiosteoporotic drugs on fracture incidence between diabetic and nondiabetic patients with osteoporosis. Although more studies are required for stronger recommendations to be issued, bisphosphonates appear to be the first-line drug for treatment of osteoporosis in diabetic patients, while denosumab seems preferable for older patients, particularly for those with impaired renal function, and osteoanabolic agents should be reserved for patients with more severe forms of osteoporosis.

Vitamin D and new insights into pathophysiology of type 2 diabetes

Deficiency in vitamin D plays a role in the onset and development of insulin resistance (IR) and type 2 diabetes (T2DM). A normal level of vitamin D is able to reduce low grade inflammation, which is a major process in inducing insulin resistance. It is also engaged in maintaining low resting levels of reactive species and radicals, normal Ca²⁺ signaling, a low expression of pro-inflammatory cytokines but increased formation of anti-inflammatory cytokines. Vitamin D is also able to prevent hypermethylation (of DNA) and consequent functional inactivation of many genes, as well as other epigenetic alterations in β cells and in other insulin-sensitive peripheral tissues, mainly liver, adipose tissue and muscle. Vitamin D deficiency thus belongs to key factors accelerating the development of IR and consequently T2DM as well. However, vitamin D supplementation aimed at the control of glucose homeostasis in humans showed controversial effects. As a result, further studies are running to gain more detailed data needed for the full clinical utilization of vitamin D supplementation in the prevention and treatment of T2DM. Until new results are published, supplementation with high doses of vitamin D deficiency is not recommended. However, prevention of vitamin D deficiency and its correction are highly desired.

Diabetes and Bone Involvement in Primary Hyperparathyroidism: Literature Review and Our Personal Experience

BACKGROUND

Primary hyperparathyroidism (PHPT) and type 2 diabetes mellitus (T2DM) are common endocrine disorders impacting on skeletal health, whose concomitant occurrence is becoming more frequent.

PATIENTS AND METHODS

We searched the PubMed database from the National Library of Medicine about the relationship between T2DM and its treatment and bone manifestations of PHPT. Thereafter, we retrospectively evaluated a consecutive series of 472 PHPT patients. Among them 55 were also affected by T2DM. At the diagnosis of PHPT we compared bone turnover markers and bone densitometry between 55 patients with and 417 without T2DM and in the former group according to antidiabetic treatment.

RESULTS

Few data are available about T2DM and PHPT bone involvement, studies about T2DM treatments and PHPT bone manifestations are lacking. Among patients with PHPT of our series, those with T2DM were older, had a lower prevalence of osteitis fibrosa cystica, higher lumbar and femoral T-scores than the remaining patients. No difference was disclosed among the diabetic patients according to ongoing antidiabetic treatment, even though modern treatments were under-represented.

CONCLUSIONS

No clinical study specifically evaluated the impact of T2DM on bone involvement in PHPT. In our experience, diabetic patients resulted more frequently "mild asymptomatic" than non-diabetic patients and showed a lower prevalence of radiological PHPT bone manifestations. The treatment of T2DM does not seem to affect the biochemical or clinical features of PHPT in our series. Further studies are needed to fully disclose the influence of T2DM and antidiabetic treatment on bone health in patients with PHPT.

Circulating osteocalcin: A potential predictor of ketosis in type 2 diabetes

AIMS

Osteocalcin contributes to the regulation of endocrine system. However, the association between osteocalcin and ketosis has not been evaluated. We thus aimed to explore the relationship between total osteocalcin and risk of ketosis in type 2 diabetes (T2DM).

MATERIALS AND METHODS

We identified 6157 diabetes patients from Shanghai Tenth People's Hospital between 1 January 2011 and 1 March 2017. Six hundred eight subjects were enrolled in the retrospective cross-sectional study: 304 T2DM patients with ketosis whose age, gender, and body mass index were matched with 304 T2DM patients without ketosis. A further retrospective nested case-control study was conducted in 252 T2DM patients without ketosis for a mean duration of 21.58 ± 12.43 months to investigate the occurrence of ketosis.

RESULTS

Osteocalcin levels were negatively correlated with blood ketones (adjusted r = -0.263) and urine ketones (adjusted r = -0.183). The inverse dose-dependent relationship of osteocalcin and risk of ketosis was present across osteocalcin level quintiles (top quintile as the reference, adjusted odds ratio [95% CI] = 2.56 [0.80-8.17], 3.71 [0.90-15.29], 10.77 [2.63-44.15], 23.81 [4.32-131.17] per osteocalcin quintile, respectively). Ketosis occurred in 17 of the 252 T2DM patients during follow-up. The Cox regression analysis indicated that osteocalcin was an independent protective factor against development of ketosis (adjusted hazard ratio [95% CI]: 0.668 [0.460-0.971]).

CONCLUSIONS

Total osteocalcin can be used as a predictor of ketosis in T2DM.

Primary hyperparathyroidism and hypertension

Although untreated primary hyperparathyroidism is associated with increased cardiovascular mortality, controversy exists regarding the therapeutic effects of parathyroidectomy on cardiovascular health. This review will examine the evidence linking primary hyperparathyroidism (PHPT) and cardiovascular disease, specifically hypertension, and evaluate the available literature regarding the natural history of hypertension after successful parathyroidectomy.

The characteristics of clinical changes in primary hyperparathyroidism in Chinese patients

In Western countries, the presentation of primary hyperparathyroidism (PHPT) changed from a symptomatic to an asymptomatic disease after the 1970s, whereas in China, only one study has evaluated the changing clinical characteristics and biochemical profiles of PHPT patients. The aim of this study was to explore changes in the clinical characteristics of PHPT in Chinese patients. Overall, 140 consecutive patients with PHPT were studied between January 1, 2010 and June 30, 2016. The patients were divided into two groups: 32 consecutive patients from January 1, 2010 to March 31, 2013 were included in group 1, and 108 consecutive patients from April 1, 2013 to June 30, 2016 were included in group 2. The most frequent complaints were ostealgia (46.02%), urolithiasis (41.59%), constipation (25.66%), fatigue (18.58%), polydipsia and polyuria (15.93%) and fracture history (15.04%). The number of cases in group 2 was 3.38-fold greater than that of group 1. The parathyroid hormone (PTH) and fasting blood glucose (FPG) levels were higher in group 1 than those in group 2 (p = 0.039, p < 0.001). In 62.14% of patients with PHPT, the proportion of the first diagnosis due to hypercalcemia found using a multichannel autoanalyzer in group 1 was lower than that found in group 2 (p = 0.039), and the proportion of the first diagnosis due to parathyroid lesions captured using routine neck ultrasonography in group 1 was higher than in group 2 (p = 0.003). The proportion of parathyroid carcinoma cases was higher in group 1 than group 2 (p = 0.036). Cases of PHPT increased with time, but the proportion of parathyroid carcinoma cases was lower in group 1 than that in group 2. Over time, the first diagnosis switched from parathyroid lesions captured by routine neck ultrasound to hypercalcemia found by a multichannel autoanalyser. At our centre, PHPT in Chinese patients still demonstrates classic characteristics.

Salts and energy balance: A special role for dietary salts in metabolic syndrome

BACKGROUND

Dietary salts sodium (Na⁺), potassium (K⁺), magnesium (Mg2⁺), and calcium (Ca2⁺) are important in metabolic diseases. Yet, we do not have sufficient understanding on the salts global molecular network in these diseases. In this systematic review we have pooled information to identify the general effect of salts on obesity, insulin resistance and hypertension.

AIMS

To assess the roles of salts in metabolic disorders by focusing on their individual effect and the network effect among these salts.

METHODS

We searched articles in PubMed, EMBASE and Google Scholar. We selected original laboratory research, systematic reviews, clinical trials, observational studies and epidemiological data that focused on dietary salts and followed the preferred reporting items for systematic review in designing the present systematic review.

RESULTS

From the initial search of 2898 studies we selected a total of 199 articles that met our inclusion criteria and data extraction. Alterations in metabolic pathways associated with the sensitivity of sodium, potassium, magnesium and calcium may lead to obesity, hypertension, and insulin resistance. We found that the results of most laboratory research, animal studies and clinical trials are coherent but some research outcome are either inconsistent or inconclusive.

CONCLUSION

Important of salts in metabolic disorder is evident. In order to assess the effects of dietary salts in metablic diseases, environmental factors, dietary habits, physical activity, and the microbiome, should be considered in any study. Although interest in this area of research continues to grow, the challenge is to integrate the action of these salts in metabolic syndrom.

The effect of surgery on fat mass, lipid and glucose metabolism in mild primary hyperparathyroidism

CONTEXT

Mild primary hyperparathyroidism has been associated with increased body fat mass and unfavorable cardiovascular risk factors.

OBJECTIVE

To assess the effect of parathyroidectomy on fat mass, glucose and lipid metabolism.

DESIGN, PATIENTS, INTERVENTIONS, MAIN OUTCOME MEASURES

119 patients previously randomized to observation (OBS; n = 58) or parathyroidectomy (PTX; n = 61) within the Scandinavian Investigation of Primary Hyperparathyroidism (SIPH) trial, an open randomized multicenter study, were included. Main outcome measures for this study were the differences in fat mass, markers for lipid and glucose metabolism between OBS and PTX 5 years after randomization.

RESULTS

In the OBS group, total cholesterol (Total-C) decreased from mean 5.9 (±1.1) to 5.6 (±1.0) mmol/L (P = 0.037) and LDL cholesterol (LDL-C) decreased from 3.7 (±1.0) to 3.3 (±0.9) mmol/L (P = 0.010). In the PTX group, the Total-C and LDL-C remained unchanged resulting in a significant between-group difference over time (P = 0.013 and P = 0.026, respectively). This difference was driven by patients who started with lipid-lowering medication during the study period (OBS: 5; PTX: 1). There was an increase in trunk fat mass in the OBS group, but no between-group differences over time. Mean 25(OH) vitamin D increased in the PTX group (P < 0.001), but did not change in the OBS group. No difference in parameters of glucose metabolism was detected.

CONCLUSION

In mild PHPT, the measured metabolic and cardiovascular risk factors were not modified by PTX. Observation seems safe and cardiovascular risk reduction should not be regarded as a separate indication for parathyroidectomy based on the results from this study.

Long-term benefits and risks of parathyroid hormone treatment in compliant osteoporotic patients. A Danish national register based cohort study

PURPOSE

Medical treatment of osteoporosis should preferably be both effective and have minimal side effects. The aim of the present study was to examine long-term benefits and risks of parathyroid hormone (PTH) treatment in compliant patients.

METHODS

This is a nationwide retrospective cohort study based on national registers in which we identified 1739 patients treated with PTH (2003-2010) (index cases) for at least 18 months and with a medication possession rate of > 0.8. For comparison, patients treated with bisphosphonate (BP) (n = 13,131) and anti-osteoporotic treatment-naïve controls (n = 12,721) were selected. Incidence of fractures, drug consumption, and comorbidity were compared between the three cohorts. Mean follow-up of the PTH-treated patients was 4.3 years (range 1.8-8.7 years).

RESULTS

Before initiation of treatment, PTH patients had a significantly higher Charlson comorbidity index score and more osteoporotic fractures than both BP patients and controls. No difference was detected in the incidence of fractures during PTH treatment or years after between PTH patients and BP patients. No significant difference in the use of drugs was seen between PTH and BP patients, except for PPI intake which was higher in PTH patients. No significant increases were found in the incidence of cancers or other ICD-10 diagnoses among PTH-treated patients in comparison with both BP and controls.

CONCLUSION

Overall, PTH treatment is effective and safe. Following PTH treatment in compliant patients, neither fracture incidence nor drug consumption differed between PTH-treated and BP-treated patients, despite the fact that PTH-treated patients had more severe osteoporosis. No increased incidence of malignant diseases or other diseases was detected.

Theoretical overview of clinical and pharmacological aspects of the use of etelcalcetide in diabetic patients undergoing hemodialysis

Etelcalcetide is the first intravenous calcimimetic agent authorized for the treatment of secondary hyperparathyroidism (sHPT) in patients undergoing hemodialysis in Europe, the US, and Japan. The relationship between sHPT and diabetes resides on complex, bidirectional effects and largely unknown homeostatic mechanisms. Although 30% or more patients with end-stage renal disease are diabetics and about the same percentage of those patients suffer from sHPT associated with hemodialysis, no data on the specificities of the use of etelcalcetide in such patients are available yet. Regarding pharmacokinetic interactions, etelcalcetide may compete with oral hypoglycemics recommended for use in patients undergoing hemodialysis and insulins detemir and degludec, causing unexpected hypocalcemia or hypoglycemia. More importantly, hypocalcemia, a common side effect of etelcalcetide, may cause decompensation of preexisting cardiac insufficiency in diabetic patients or worsen dialysis-related hypotension and lead to hypotension-related cardiac events, such as myocardial ischemia. In diabetic patients, hypocalcemia may lead to dangerous ventricular arrhythmias, as both insulin-related hypoglycemia and hemodialysis prolong QT interval. Patients with diabetes, therefore, should be strictly monitored for hypocalcemia and associated effects. Due to an altered parathormone activity in this patient group, plasma calcium should be the preferred indicator of etelcalcetide effects. Until more clinical experience with etelcalcetide is available, the clinicians should be cautious when using this calcimimetic in patients with diabetes.

Calcium homeostasis in diabetes mellitus

Diabetes mellitus (DM) is becoming a lifestyle-related pandemic disease. Diabetic patients frequently develop electrolyte disorders, especially diabetic ketoacidosis or nonketotic hyperglycemic hyperosmolar syndrome. Such patients show characteristic potassium, magnesium, phosphate, and calcium depletion. In this review, we discuss a homeostatic mechanism that links calcium and DM. We also provide a synthesis of the evidence in favor or against this linking mechanism by presenting recent clinical indications, mainly from veterinary research. There are consistent results supporting the use of calcium and vitamin D supplementation to reduce the risk of DM. Clinical trials support a marginal reduction in circulating lipids, and some meta-analyses support an increase in insulin sensitivity, following vitamin D supplementation. This review provides an overview of the calcium and vitamin D disturbances occurring in DM and describes the underlying mechanisms. Such elucidation will help indicate potential pathophysiology-based precautionary and therapeutic approaches and contribute to lowering the incidence of DM.

Maternal Early Pregnancy Plasma Concentration of 25-Hydroxyvitamin D and Risk of Gestational Diabetes Mellitus

We examined whether 25-Hydroxyvitamin D [25(OH) D] concentrations, measured at the first prenatal visit, would be associated with risk of gestational diabetes mellitus (GDM). From July 2015 to June 2016, consecutive women who admitted to the two-obstetrics center in china were included. Relevant data were collected between 24 and 28 weeks of gestation, including fasting plasma glucose (FPG) and 25(OH) D concentrations at the first prenatal visit and the one-step GDM screened with 75-g oral glucose tolerance test (OGTT). Blood from women at first prenatal visit was available for 827 women and 101 of them developed GDM (12.2%). The GDM distribution across the 25(OH) D quartiles ranged between 3.9% (fourth quartile, Q4) and 26.1% (first quartile, Q1). The median plasma concentration of 25(OH) D at first prenatal visit was significantly lower in women who developed GDM compared with those not developed (p < 0.001). In multivariate models comparing the 25(OH) D of Q1, second (Q2) and third quartiles (Q3) against the Q4, it observed that concentrations of 25(OH) D in Q1 and Q2 were associated with later developed GDM, and risk of GDM was increased by 240 and 48%, respectively. The women group with combined vitamin D deficiency and obesity had an OR of 4.66 [95% CI (2.91-8.15); p < 0.001] for GDM compared to those without vitamin D deficiency and obesity. Low 25(OH) D concentrations at the first prenatal visit were associated with increased risk of GDM and might be useful in identifying women at risk of GDM for performing early prevention strategies.

Effect of Vitamin D Treatment on Glucose Homeostasis and Metabolism in Lebanese Older Adults: A Randomized Controlled Trial

BACKGROUND

A low serum 25-hydroxyvitamin D [(25(OH) D)] concentration was shown to correlate with higher fasting blood glucose (FBG) and insulin levels. Since age affect insulin sensitivity and the metabolism, we aimed in this randomized controlled trial to investigate the effect of vitamin D supplementation on glucose homeostasis and index of insulin resistance in elderly subjects living in Beirut, Lebanon.

METHODS

Participants (n= 115) deficient in vitamin D were randomly divided into two groups, a group receiving 30,000 IU cholecalciferol/week for a period of 6 months, and a placebo group. The index of insulin resistance HOMA (homeostasis model assessment) was the primary outcome. Glucose homeostasis and metabolic markers were also measured at start of treatment and at 6 months.

RESULTS

Vitamin D supplementation led to significant improvements in blood levels of [25(OH) D] (P< 0.0001), and a significant decreased of HOMA, PTH and FBG concentrations (P< 0.0001) in the intervention group compared to placebo. No significant changes were observed in HbA1c levels for both groups. Total cholesterol and LDL cholesterol concentrations have also decreased significantly in the intervention group (P< 0.0001).

CONCLUSION

Short-term supplementation with cholecalciferol improved vitamin D status, and markers of insulin resistance in healthy elder population. This trial was registered at ClinicalTrials.gov; Identifier number#:NCT03478475.

Recurrent diabetic ketoacidosis: a rare presenting manifestation of primary hyperparathyroidism

We report a rare case of primary hyperparathyroidism in a young female who presented with recurrent diabetic ketoacidosis. The patient had suffered an episode of acute pancreatitis in the past. On evaluation patient was found to have primary hyperparathyroidism and after removal of left inferior parathyroid adenoma her insulin requirement decreased by twelve units.

Effect of teriparatide treatment on endothelial function, glucose metabolism and inflammation markers in patients with postmenopausal osteoporosis

OBJECTIVE

Teriparatide, an anabolic agent used in the treatment of postmenopausal osteoporosis, can induce effects similar to primary hyperparathyroidism. Our objective was to evaluate the effects of teriparatide on endothelial functions, glucose metabolism and inflammation markers in patients diagnosed with postmenopausal osteoporosis.

DESIGN, PATIENTS AND MEASUREMENTS

This was a single-centre, single-arm, 6-month prospective study. Twenty-three postmenopausal women over 65 years old with a lumbar spine or femoral neck T-score of -4·0 or lower and having at least two compression fractures in thoracic or lumbar spine were studied. Low-dose intermittent teriparatide (20 μg/day) was supplemented with calcium carbonate (1000 mg elemental calcium) and 880 IU cholecalciferol for 6 months. The biochemical parameters for glucose metabolism, inflammation and atherosclerosis were determined. For the assessment of vascular endothelial function, carotid intima-media thickness (CIMT), brachial artery intima-media thickness (BIMT), per cent change in flow-mediated dilation (FMD%) and nitroglycerine-induced dilations (NID%) were measured on ultrasonography.

RESULTS

The fasting plasma glucose, homoeostatic model assessment of insulin resistance, fibrinogen, homocysteine and high-density lipoprotein cholesterol increased significantly with teriparatide treatment (P < 0·05 for all). Baseline CIMT and BIMT did not change significantly with 6 months of teriparatide treatment (P > 0·05); however, FMD% and NID% showed significant decrease after treatment (P < 0·01 for both).

CONCLUSIONS

Intermittent teriparatide treatment may adversely affect some parameters of glucose metabolism, inflammation and endothelial function. On the basis of our findings, further large-scale and controlled studies are needed to clarify the exact effect of teriparatide treatment on glucose metabolism, inflammation and endothelial function.

Parathyroidectomy Decreases Insulin Resistance Index in Patients with Primary Hyperparathyroidism

Primary hyperparathyroidism (PHPT) has been considered a cause of insulin resistance (IR) and impaired glucose metabolism. However, there are conflicting results related with the recovery of insulin resistance in patients with PHPT following curative parathyroidectomy. Our aim is to evaluate the effects of curative parathyroidectomy on IR in patients with PHPT. This is a prospective interventional study. Twenty-one consecutive patients with symptomatic PHPT were included into the study. All patients underwent parathyroidectomy. Fasting serum glucose, calcium, phosphorous, parathormone, plasma insulin, and vitamin D levels were measured both at baseline and 2 months after parathyroidectomy. Insulin resistance was calculated by homeostasis of model assessment-insulin resistance (HOMA-IR). Two months after curative parathyroidectomy, serum levels of calcium (p = 0.001), PTH (p < 0.001), insulin (p = 0.003), and HOMA-IR (p = 0.003) decreased, while phosphorous levels increased (p = 0.001). During this period, no changes were observed at vitamin D and glucose levels. We concluded that curative parathyroidectomy decreases HOMA-IR index in patients with PHPT. Studies with larger population and longer follow-up period are required to confirm our results.

Low serum 25(OH)D levels are assocıated to hıgher BMI and metabolic syndrome parameters in adult subjects in Turkey

BACKGROUND

The aim of this study was to investigate the association of 25(OH)D levels with biochemical, anthropometric, and metabolic data obtained from normal and obese people.

METHODS

This study was carried out on 90 individuals between the ages of 18 to 63 that had various body mass indexes. Blood samples and anthropometric measurements were taken.

RESULTS

Waist circumferences, fat mass, LDL cholesterol levels, HDL cholesterol levels, 25(OH)D levels, and triglyceride levels were significantly different according to the body mass index groups of the participants (p<0.05). When compared to the normal body mass index group, both other groups (overweight and obese) had higher waist circumferences, triglyceride levels, LDL cholesterol levels, fasting insulin levels, HOMA-IR ratios, parathyroid hormone levels, and fat mass, and had lower 25(OH)D levels (p<0.05). The overweight group participants had higher 25(OH)D levels than the obese group, and had lower waist circumferences, fat mass, fasting insulin level, HOMA-IR ratios, and HbA1C and PTH levels than those in the obese group (p<0.05).

CONCLUSION

In conclusion, the mean level of 25(OH)D is very low in overweight and obese individuals and low serum 25(OH)D levels appear to be associated with obesity, visceral obesity, hypertriglyceridemia, insulin resistance, and metabolic syndrome in obese patients.

Relationship Between Parathormone and Obesity-Linked Disorders

BACKGROUND

In this study, we aimed to investigate whether high parathormone (PTH) levels in obese patients contribute to the metabolic complications of obesity.

METHODS

A total of 400 obese subjects aged 18-65 years were included. Anthropometric bioelectrical bioimpedance measures, blood tests, and 75 gram oral glucose tolerance test results were evaluated.

RESULTS

Of the 400 obese subjects, 335 were female. The mean age was 39 ± 10 years. The median body mass index was 36 (interquartile range 34-41). Subjects were divided into quartiles according to blood PTH levels. Groups included quartile 1 [n = 100, median PTH; 42 (range 36-45)], quartile 2 [n = 100, median PTH; 55 (51-59)], quartile 3 [n = 100, median PTH; 73 (68-78)], and quartile 4 [n = 100, median PTH; 99 (89-125)]. Quartiles were evaluated with a generalized linear model adjusted for age, sex, and season of recruitment. Systolic and diastolic blood pressure, fasting glucose, homeostatic model assessment-estimated insulin resistance, insulin sensitivity index, triglyceride level, and high-density lipoprotein cholesterol (HDL-C) were not different among quartiles. PTH and 25 hydroxyvitamin D (25(OH)D) were not associated with higher odds of prevalent metabolic syndrome in obese subjects (odds ratio, OR, 0.99 [95% confidence interval, CI, 0.981.00], P = 0.38 and 0.99 95% CI 0.96-1.01], P = 0.46, respectively). Decreased 25(OH)D levels were significantly correlated with higher odds of low HDL-C (OR 0.96 [95% CI 0.93-0.99], P = 0.04).

CONCLUSIONS

PTH does not contribute to the occurrence of metabolic components of obesity, but there is a positive correlation between 25(OH)D and HDL-C.

Primary hyperparathyroidism and vitamin D deficiency

Primary hyperparathyroidism (PHPT) and vitamin D (VD) deficiency are frequent conditions due to the widespread application of assays for calcium and VD. PHPT presentation is dominated by diversity in its expression and the current predominance of asymptomatic forms. VD, which plays a major role in calcium and phosphate homeostasis, is also involved in many physiological processes in this disease, such as lipid and glucose metabolism, and in the signalling pathways and functioning of many cell types. The bone and cardiometabolic complications described in PHPT are exacerbated by vitamin D deficiency, the prevalence of which varies according to many parameters (environment, skin pigmentation, associated chronic diseases, liver and kidney function, assay kit used, etc.). In response to this observation, experts in field from medical societies validated the indication for systematic assay of VD occurring with PHPT and the need for replacement in case of deficiency. Several epidemiological studies have confirmed that replacement with natural vitamin D is well tolerated and safe in subjects with PHPT and VD deficiency. This supplementation reduces hyperparathormonemia, does not have symptomatic effects on calciuria, and especially improves the bone and functional condition of patients.

High prevalence of metabolic syndrome in a mestizo group of adult patients with primary hyperparathyroidism (PHPT)

BACKGROUND

Primary hyperparathyroidism (PHPT) and metabolic syndrome (MS) have been independently related to cardiovascular morbidities, however this association is still controversial. Mexican population has a high prevalence of metabolic syndrome, however its frequency seems to be even higher than expected in patients with PHPT.

METHODS

We retrospectively reviewed the charts of patients that underwent parathyroidectomy for PHPT in a referral center and used the criteria from the National Cholesterol Educational Program (NCEP)/Adult Treatment Panel III (ATP III) to define MS before surgery. We compared the characteristics between the patients with and without MS.

RESULTS

60 patients were analyzed, 77% were female and 72% had a single parathyroid adenoma. MS was present in 59% of the patients, this group was significantly older (57 vs. 48 years, p = 0.01) and they had lower iPTH (115 vs. 161 ng/ml, p = 0.017). Other parameters did not show differences.

CONCLUSIONS

MS is frequent in our population diagnosed with primary hyperparathyroidism, adverse cardiovascular parameters are common and significant differences in calcium metabolism compared to the non-MS group are present.

Hyperparathyroidism and new onset diabetes after renal transplantation

BACKGROUND

Secondary hyperparathyroidism persists after renal transplantation in a substantial number of patients. Primary hyperparathyroidism and secondary hyperparathyroidism are both associated with abnormalities in glucose metabolism, such as insufficient insulin release and glucose intolerance. The association of hyperparathyroidism and diabetes after renal transplantation has, as far as we know, not been studied. Our aim was to investigate whether hyperparathyroidism is associated with new-onset diabetes mellitus after transplantation (NODAT) during the first year posttransplantation.

STUDY DESIGN

In a retrospective study, we analyzed data on patient characteristics, treatment details, and parathyroid hormone (PTH) in 245 adult nondiabetic patients who underwent renal transplantation between January 2000 and June 2011.

RESULTS

The first year cumulative incidence of NODAT was 15%. The first serum PTH value after transplantation was above normal range in 74% of the patients. In multiple logistic regression analysis, PTH levels above twice normal range (>13.80 pmol/L) were significantly associated with NODAT (odds ratio [OR], 4.25; 95% confidence interval [CI], 1.13-15.92; P = .03) compared with PTH within normal range (≤6.9 pmol/L). Age between 45 and 65 years (OR, 2.80; 95% CI, 1.07-7.36; P = .04) compared with age <45 years was also associated with NODAT.

CONCLUSION

We found a strong association between hyperparathyroidism and NODAT in the first year after renal transplantation. Both conditions are common and have a negative impact on graft and patient survivals. Our results should be confirmed in prospective studies.

Increased serum calcium levels and risk of type 2 diabetes in individuals at high cardiovascular risk

OBJECTIVE

Insulin resistance and secretion depend on calcium homeostasis. Cross-sectional studies have associated elevated serum calcium levels with markers of impaired glucose metabolism. However, only one prospective cohort study has demonstrated an increased risk of diabetes in individuals with increased serum calcium concentrations. The aim of the current study was to prospectively investigate the association between albumin-adjusted serum calcium concentrations and type 2 diabetes in subjects at high cardiovascular risk.

RESEARCH DESIGN AND METHODS

Prospective assessment of participants from two Spanish PREDIMED study centers where serum calcium levels were measured at baseline and yearly during follow-up. Multivariate-adjusted Cox regression models were fitted to assess associations between baseline and changes during follow-up in serum calcium levels and relative risk of diabetes incidence.

RESULTS

After a median follow-up of 4.78 years, 77 new cases of type 2 diabetes occurred. An increase in serum calcium levels during follow-up was related to an increased risk of diabetes. In comparison with individuals in the lowest tertile (-0.78 ± 0.29 mg/dL), the hazard ratio (HR) and 95% CI for diabetes incidence in individuals in the higher tertile of change (0.52 ± 0.13 mg/dL) during follow-up was 3.48 (95% CI 1.48-8.17; P for trend = 0.01). When albumin-adjusted serum calcium was analyzed as a continuous variable, per 1 mg/dL increase, the HR of diabetes incidence was 2.87 (95% CI 1.18-6.96; P value = 0.02). These associations remained significant after individuals taking calcium supplements or having calcium levels out of normal range had been excluded.

CONCLUSIONS

An increase in serum calcium concentrations is associated with an increased risk of type 2 diabetes in individuals at high cardiovascular risk.

Calcium and phosphate concentrations and future development of type 2 diabetes: the Insulin Resistance Atherosclerosis Study

AIMS/HYPOTHESIS

Low phosphate and high calcium concentrations have been linked to altered glucose tolerance and reduced insulin sensitivity in non-diabetic individuals. The aim of this study was to examine the relationships of calcium and phosphate levels and the calcium-phosphate product with the development of type 2 diabetes.

METHODS

Participants were 863 African-Americans, Hispanics and non-Hispanic whites in the Insulin Resistance Atherosclerosis Study who were free of diabetes at baseline. The mean follow-up period was 5.2 years. The insulin sensitivity index (SI) and acute insulin response (AIR) were directly measured using the frequently sampled IVGTT.

RESULTS

Calcium concentration (OR per 1 SD unit increase, 1.26 [95% CI 1.04, 1.53]) and calcium-phosphate product (OR 1.29 [95% CI 1.04, 1.59]) were associated with incident diabetes after adjustment for demographic variables, family history of diabetes, and 2 h glucose. The relationship between phosphate concentration and progression to diabetes was close to statistical significance (OR 1.21 [95% CI 0.98, 1.49]). Calcium concentration (OR 1.37 [95% CI 1.09, 1.72]) and calcium-phosphate product (OR 1.39 [95% CI 1.09, 1.77]) remained associated with incident diabetes after additional adjustment for BMI, plasma glucose, SI, AIR, C-reactive protein, estimated GFR, diuretic drugs and total calcium intake.

CONCLUSIONS/INTERPRETATION

Elevated serum calcium and calcium-phosphate product are associated with increased risk of developing type 2 diabetes independently of measured glucose, insulin secretion and insulin resistance. Future studies need to analyse the role of calcium-phosphate homeostasis in the pathophysiology of diabetes.

The alliance of mesenchymal stem cells, bone, and diabetes

Bone fragility has emerged as a new complication of diabetes. Several mechanisms in diabetes may influence bone homeostasis by impairing the action between osteoblasts, osteoclasts, and osteocytes and/or changing the structural properties of the bone tissue. Some of these mechanisms can potentially alter the fate of mesenchymal stem cells, the initial precursor of the osteoblast. In this review, we describe the main factors that impair bone health in diabetic patients and their clinical impact.

Bone Remodeling and Energy Metabolism: New Perspectives

Bone mineral, adipose tissue and energy metabolism are interconnected by a complex and multilevel series of networks. Calcium and phosphorus are utilized for insulin secretion and synthesis of high energy compounds. Adipose tissue store lipids and cholecalciferol, which, in turn, can influence calcium balance and energy expenditure. Hormones long-thought to solely modulate energy and mineral homeostasis may influence adipocytic function. Osteoblasts are a target of insulin action in bone. Moreover, endocrine mediators, such as osteocalcin, are synthesized in the skeleton but regulate carbohydrate disposal and insulin secretion. Finally, osteoblasts and adipocytes originate from the same mesenchymal progenitor. The mutual crosstalk between osteoblasts and adipocytes within the bone marrow microenvironment plays a crucial role in bone remodeling. In the present review we provide an overview of the reciprocal control between bone and energy metabolism and its clinical implications.

The roles of vitamin D in skeletal muscle: form, function, and metabolism

Beyond its established role in bone and mineral homeostasis, there is emerging evidence that vitamin D exerts a range of effects in skeletal muscle. Reports of profound muscle weakness and changes in the muscle morphology of adults with vitamin D deficiency have long been described. These reports have been supplemented by numerous trials assessing the impact of vitamin D on muscle strength and mass and falls in predominantly elderly and deficient populations. At a basic level, animal models have confirmed that vitamin D deficiency and congenital aberrations in the vitamin D endocrine system may result in muscle weakness. To explain these effects, some molecular mechanisms by which vitamin D impacts on muscle cell differentiation, intracellular calcium handling, and genomic activity have been elucidated. There are also suggestions that vitamin D alters muscle metabolism, specifically its sensitivity to insulin, which is a pertinent feature in the pathophysiology of insulin resistance and type 2 diabetes. We will review the range of human clinical, animal, and cell studies that address the impact of vitamin D in skeletal muscle, and discuss the controversial issues. This is a vibrant field of research and one that continues to extend the frontiers of knowledge of vitamin D's broad functional repertoire.

Energy metabolism and the skeleton: Reciprocal interplay

The relation between bone remodelling and energy expenditure is an intriguing, and yet unexplained, challenge of the past ten years. In fact, it was only in the last few years that the skeleton was found to function, not only in its obvious roles of body support and protection, but also as an important part of the endocrine system. In particular, bone produces different hormones, like osteocalcin (OC), which influences energy expenditure in humans. The undercarboxylated form of OC has a reduced affinity for hydroxyapatite; hence it enters the systemic circulation more easily and exerts its metabolic functions for the proliferation of pancreatic β-cells, insulin secretion, sensitivity, and glucose tolerance. Leptin, a hormone synthesized by adipocytes, also has an effect on both bone remodelling and energy expenditure; in fact it inhibits appetite through hypothalamic influence and, in bone, stimulates osteoblastic differentiation and inhibits apoptosis. Leptin and serotonin exert opposite influences on bone mass accrual, but several features suggest that they might operate in the same pathway through a sympathetic tone. Serotonin, in fact, acts via two opposite pathways in controlling bone remodelling: central and peripheral. Serotonin product by the gastrointestinal tract (95%) augments bone formation by osteoblast, whereas brain-derived serotonin influences low bone mineral density and its decrease leads to an increase in bone resorption parameters. Finally, amylin (AMY) acts as a hormone that alters physiological responses related to feeding, and plays a role as a growth factor in bone. In vitro AMY stimulates the proliferation of osteoblasts, and osteoclast differentiation. Here we summarize the evidence that links energy expenditure and bone remodelling, with particular regard to humans.

Investigation of insulin resistance in patients with normocalcemic primary hyperparathyroidism

While derangements in glucose metabolism in patients with primary hyperparathyroidism are well-defined, this issue is not investigated in patients with normocalcemic primary hyperparathyroidism (NPHPT). The aim of this study was to investigate the presence of insulin resistance in patients with NPHPT. Eighteen patients with NPHPT (two males and 16 females) and 18 healthy volunteers were enrolled into the study. Secondary causes of parathyroid hormone elevations were excluded in all patients. Blood samples were obtained for the measurement of serum calcium, phosphate, alkaline phosphatase (ALP), albumin, creatinine, glucose, and serum lipid levels. Glucose and insulin responses to oral glucose tolerance test (OGTT) were obtained. Homeostasis model assessment (HOMA-IR) was also used as an indice of insulin resistance. Patients and control subjects had similar age, body mass index, and sex distribution. Although within normal limits, serum calcium and ALP levels were higher in patients than in the control subjects. None of the patients and the control subjects had diabetes mellitus, while eight patients and six control subjects had impaired glucose tolerance. Insulin responses to OGTT and HOMA-IR were not significantly different among the patient and control subjects. In addition, both groups have similar serum lipid levels. Patients with NPHPT do not exhibit insulin resistance and glucose intolerance. Since so little is known about this form of disease, subjects should be monitored regularly for the metabolic aspects of the disease as well as the progression of their disease.

Determination of vitamin D in relation to body mass index and race in a defined population of black and white women

OBJECTIVE

To examine the contributions of obesity and race to levels of 25-hydroxyvitamin D [25(OH)D] and parathyroid hormone (PTH) in a defined cohort of black and white women.

METHODS

An interventional study was conducted from October 2004 to March 2008, among 219 healthy female volunteers. Serum 25(OH)D and PTH levels were determined in 117 African American women and 102 white women and the results were compared with body mass index (BMI), percentage body fat, serum lipids, and PTH levels.

RESULTS

Black women had lower median levels of 25(OH)D compared with white women (27.3 nmol/L vs 52.4 nmol/L; P<0.001). Serum levels of 25(OH)D below 50 nmol/L were found in 98% of black women and 45% of white women (P<0.001). The differences between the racial groups in the levels of 25(OH)D persisted despite adjustments for body weight, percentage body fat, and BMI. Black women had higher median serum levels of PTH than white women (31.9 pg/mL vs 22.3 pg/mL; P<0.01).

CONCLUSION

African American women are at significant risk for low vitamin D levels. Studies are needed to determine if low vitamin D status in young African American women is associated with a greater risk for vitamin D-related chronic diseases that can be reduced with vitamin D supplementation.

A structural equation model for assessment of links between changes in serum triglycerides, -urate, and -glucose and changes in serum calcium, -magnesium and -phosphate in type 2 diabetes and non-diabetes metabolism

Background

This study investigates the associations between changes in serum Triglycerides (S-TG), -Urate (S-Urate), and -Glucose (S-Glu) and changes in serum Calcium (S-Ca), -Magnesium (S-Mg), and -Phosphate (S-P) in patients with type 2 diabetes compared with non-diabetic patients.

Methods

The analysis is based on data collected from a secondary prevention population of women and men (W/M) at risk for cardiovascular disease (type 2 diabetes, 212/200; non-diabetes 968/703). The whole population (n = 2083) had a mean age of 51.0 (9.7) years and was stratified for sex and according to type 2 diabetes or non-diabetes. The patients were followed for, either half a year or one year and changes in risk factors were calculated from follow-up to baseline, the time when patients were admitted to the health center. The pattern of relationships was evaluated using a structural equation model.

Results

Higher S-TG and S-Glu but lower S-Urate was revealed at baseline in type 2 diabetes women and men as compared to their counterparts, non-diabetes patients. Women with type 2 diabetes had higher S-Ca and lower S-Mg than non-diabetes women. Changes in S-Glu were associated with changes in S-Ca (+), baseline S-Ca (+), and S-Urate (-) in type 2 diabetes men. Changes in S-Urate were associated with changes in S-Mg (+) in type 2 diabetes women and non-diabetes men. In men with non-diabetes, changes in S-Glu were associated with changes in S-Mg (-). In women with non-diabetes, changes in S-Glu were associated with changes in S-P (-) and changes in S-Urate with changes in S-Ca (+).

Conclusion

With respect to metabolic disturbances in non-diabetes and the awareness of risk for type 2 diabetes, changes in S-Glu and changes in S-Ca, S-Mg, and S-P should be considered as risk factors for cardiovascular disease. Increased early detection and corrections of high S-Ca, low S-Mg, and S-P in obese patients may improve their metabolism and reduce the risk of CVD in patients with type 2 diabetes.

Trial registration number

ISRCTN: ISRCTN79355192

Parathormone--25(OH)-vitamin D axis and bone status in children and adolescents with type 1 diabetes mellitus

BACKGROUND

Skeletal involvement in patients with type 1 diabetes mellitus (T1DM) has complex pathogenesis and despite numerous researches on this problem, many questions remain unanswered.

OBJECTIVE

This study aimed to assess bone status by measurement parathormone (PTH), 25-hydroxy vitamin D [25(OH)D] serum levels in children and adolescents with T1DM and its relation to insulin-like growth factor-1 (IGF-1), disease duration, puberty stage, and metabolic control.

PATIENTS AND METHODS

This study included 36 children and adolescents with T1DM and 15 apparently healthy controls. Serum levels of 25(OH)D, PTH, IGF-1 measured using enzyme-linked immunosorbent assay (ELISA), while glycosylated hemoglobin (HbA1c), calcium (Ca), inorganic phosphorus (PO(4) ) using autoanalyzer. Bone quality assessed using dual energy X-ray absorptiometry (DEXA).

RESULTS

Diabetic patients showed significant increase in PO(4) and PTH levels, while significant decrease in Ca, IGF-1, and 25(OH)D serum levels. As much as 52.8% of patients showed reduced 25(OH)D, and 30.65% showed elevated PTH serum levels. In diabetic patients, abnormal bone status (osteopenia-osteoporosis) found mostly in total body (94.40%) then lumber-spine (88.90%), ribs (88.90%), pelvis (86.10%), thoracic-spine (80.60%), arms (80.60%) and legs (77.80%), while head bones showed no abnormalities. Long diabetic duration had negative; meanwhile PTH, onset age, and puberty age had positive impact on bone status.

CONCLUSIONS

Children and adolescent with T1DM have abnormal bone status mostly in axial skeleton which may be contributed to impairment of formation of 25(OH)D and IGF-1. Physical activity, calcium and vitamin D supplement seem important in T1DM. Elevated serum PTH level in diabetic patients is not uncommon and its positive correlation with bone status needs further investigations.

Serum calcium level is associated with metabolic syndrome in the general population: FIN-D2D study

BACKGROUND

The aim of this cross-sectional study was to examine the association between serum calcium and the components of metabolic syndrome (MetS).

METHODS

As a part of the national prevention program of diabetes in Finland (FIN-D2D), a randomly selected study population of 4500 middle-aged men and women were recruited from three central hospital district areas. Anthropometric measurements were performed by a trained nurse. An oral glucose tolerance test was performed and serum calcium and lipids were measured. We assessed current medications, physical activity, smoking, alcohol consumption, calcium intake, and vitamin D intake. The MetS was defined according to the criteria of the updated National Education Program. The study population consisted of 2896 individuals: 1396 men (62% of invited individuals) and 1500 women (66.7% of invited individuals).

RESULTS

The mean age was 60.3±8.3 years in men and 59.8±8.5 years in women. The prevalence of MetS was 50.7% in women and 55.8% in men. The prevalence of MetS and its components, except high-density lipoprotein (HDL)-cholesterol, increased linearly with increasing serum calcium (P<0.001), even after adjustment for age, physical activity, alcohol, vitamin D intake, calcium intake, and smoking. The threshold value for serum calcium for MetS was 2.50 mmol/l in this population. The association of MetS with total serum calcium was similar even after exclusion of patients treated with hypertensive drugs. The drug treatments for hypertension, dyslipidemia, and diabetes increased in a similar pattern.

CONCLUSIONS

Serum calcium level is associated with MetS and its components, except HDL-cholesterol.

Serum calcium is positively correlated with fasting plasma glucose and insulin resistance, independent of parathyroid hormone, in male patients with type 2 diabetes mellitus

Patients with primary hyperparathyroidism have impaired glucose tolerance more often than do controls, and parathyroid resection sometimes improves this derangement. However, it is unclear whether serum calcium (Ca) or parathyroid hormone (PTH) is more strongly related to impaired glucose metabolism in subjects without primary hyperparathyroidism. In this cross-sectional study, we examined patients with type 2 diabetes mellitus (DM) (271 men and 209 women) and analyzed the relationships between serum concentrations of Ca or intact PTH and DM-related variables. Simple regression analyses showed that the level of serum Ca was significantly and positively correlated with the levels of fasting plasma glucose, immunoreactive insulin, and homeostasis model assessment insulin resistance in men (P < .05), but not in women. In contrast, intact PTH was not significantly correlated with DM-related parameters in either sex. Multiple regression analyses showed that the significant and positive correlations between serum Ca vs fasting plasma glucose and homeostasis model assessment insulin resistance in men still remained after adjustment for intact PTH as well as age, body weight, height, creatinine, albumin, phosphate, bone metabolic markers, and estradiol (P < .05). Serum Ca level is positively associated with impaired glucose metabolism, independent of PTH or bone metabolism, in men with type 2 DM.

The relationship between serum phosphate levels with childhood obesity and insulin resistance

AIM

To investigate the relationship between serum phosphate levels with obesity and insulin resistance in childhood.

METHODS

A total of 298 children and adolescents (190 obese subjects and 108 controls) were included in the study. Serum glucose, insulin, phosphate, calcium and alkaline phosphatase levels were measured after 12 h fasting at 08:00-08:30 h. We assessed insulin sensitivity by using the HOMA-IR (homeostasis model of insulin resistance) index as a surrogate marker of insulin resistance.

RESULTS

Serum levels of phosphate were significantly lower in the 6- to 12-year-old obese subjects than controls (p = 0.02, p < 0.05). At the same time, there was a moderate negative correlation between serum phosphate levels and the HOMA-IR index in the 6- to 12-year-old IR (-) obese children (r = -0.26, p = 0.02).

CONCLUSIONS

Low serum phosphate levels could contribute to the development of insulin resistance in 6- to 12-year-old obese children.

Vitamin D: emerging new roles in insulin sensitivity

The growing incidence of prediabetes and clinical type 2 diabetes, in part characterised by insulin resistance, is a critical health problem with consequent devastating personal and health-care costs. Vitamin D status, assessed by serum 25-hydroxyvitamin D levels, is inversely associated with diabetes in epidemiological studies. Several clinical intervention studies also support that vitamin D, or its active metabolite 1,25-dihydroxyvitamin D (1,25(OH)2D), improves insulin sensitivity, even in subjects with glucose metabolism parameters classified within normal ranges. The mechanisms proposed which may underlie this effect include potential relationships with improvements in lean mass, regulation of insulin release, altered insulin receptor expression and specific effects on insulin action. These actions may be mediated by systemic or local production of 1,25(OH)2D or by suppression of parathyroid hormone, which may function to negatively affect insulin sensitivity. Thus, substantial evidence supports a relationship between vitamin D status and insulin sensitivity; however, the underlying mechanisms require further exploration.

Normal parathyroid hormone levels in a diabetic patient with parathyroid adenoma

OBJECTIVE

The incidence of diabetes mellitus in patients with primary hyperparathyroidism and, conversely, primary hyperparathyroidism in diabetic patients are approximately threefold higher than the respective expected prevalence in the general populace. The diagnosis is straightforward when the patient presents hypercalcemia and inappropriately elevated serum parathyroid hormone (PTH) levels. We report a case of parathyroid adenoma in a diabetic patient with persistent hypercalcemia and normal PTH levels.

PATIENT

A 50-year-old female patient who was referred to our outpatient clinic presented with persistent hypercalcemia (serum Ca levels between 10.5 and 11 mg/dl) with a normal serum intact PTH level of 46.1 pg/ml. Her blood pressure was 120/80 mmHg, and she was being treated with antihypertensive therapy. Her HbA1c was 7.2%, and her triglycerides were in the normal range. A bone densitometry exam revealed osteopenia of radius -1.39, femoral neck -1.39, and the total hip -1.04. A neck ultrasound revealed a mass of 13 mm next to the inferior and posterior of the right thyroid lobe. A dual phase Tc-99m-sestamibi scan revealed an area of increased uptake in the same region, which is indicative of a parathyroid adenoma. The parathyroid adenoma was removed, which resulted in the achievement of normocalcemia.

CONCLUSION

Diabetic patients should be evaluated for hyperparathyroidism as associated hypertension can complicate the course of the disease. These patients should be evaluated for primary hyperparathyroidism when they exhibit persistent hypercalcemia and when clinical suspicion is aroused even if the serum PTH levels are within the normal range.

Primary hyperparathyroidism, insulin resistance, and cardiovascular disease: a review

The presentation of primary hyperthyroidism (PHPT) has changed substantially in the last decade. Before the introduction of routine calcium measurement in most automated biochemistry serum analyzers, it usually was diagnosed after renal and bony lesions already were present. Nowadays, its presentation is practically asymptomatic. Nevertheless, the cardiovascular morbidity and mortality of mild to moderate forms of PHPT reportedly are increasing. Individuals who have mild to moderate forms of PHPT have an increased risk for enduring cardiovascular disease, arterial hypertension, left ventricular hypertrophy, myocardial and valvular calcifications, altered vascular reactivity, and cardiac conduction. Finally, they also reveal alterations in carbohydrate metabolism, insulin resistance, dyslipidemia, and body composition.

Serum calcium is independently associated with insulin sensitivity measured with euglycaemic-hyperinsulinaemic clamp in a community-based cohort

AIMS/HYPOTHESIS

Diabetes mellitus type 2 is associated with altered calcium metabolism. Moreover, in diseases with supranormal serum calcium levels, such as primary hyperparathyroidism, the prevalence of diabetes is increased. Relatively little is known about the relationship between serum calcium concentration and the underlying causes of diabetes-insulin resistance and defective insulin secretion-in the normocalcaemic general population.

MATERIALS AND METHODS

We investigated associations between serum calcium concentration and insulin sensitivity and secretion in a population-based cohort of elderly men (Uppsala Longitudinal Study of Adult Men, n = 961). Insulin sensitivity index (M/I; glucose disposal rate [M] divided by mean insulin concentration [I]) was assessed using euglycaemic-hyperinsulinaemic clamp, and insulin secretion was estimated from the early insulin response (EIR) during an OGTT.

RESULTS

In a multivariable linear regression model adjusting for BMI, physical activity, smoking, consumption of tea, alcohol, coffee and dietary calcium, serum phosphate and serum creatinine, 1 SD increase in serum calcium was associated with 0.17 mg kg(-1) min(-1) (mU/l)(-1) x 100 (0.024 mg kg(-1) min(-1) [pmol/l](-1) x 100) decrease in M/I (p = 0.01). The results remained robust in individuals with normal fasting glucose, normal glucose tolerance and serum calcium within the normal range (n = 413, regression coefficient for 1 SD increase -0.45, p = 0.001). Serum calcium was not associated with EIR. Dietary intake of calcium was not independently associated with insulin sensitivity or EIR.

CONCLUSION/INTERPRETATION

Our data support the notion that endogenous calcium may be involved early in the development of diabetes and that this effect is mediated mainly through effects on insulin sensitivity rather than defective insulin secretion. Dietary intake of calcium does not seem to influence insulin sensitivity.