Finding the Optimal Dose of Vitamin D Following Roux-en-Y Gastric Bypass: A Prospective, Randomized Pilot Clinical Trial

Background  Vitamin D deficiency is common following bariatric surgery and is due to a combination of baseline deficiency and postoperative malabsorption. There are few prospective studies evaluating the appropriate dose of vitamin D to prevent and treat vitamin D deficiency following bariatric surgery. Methods  We evaluated three doses of vitamin D3 (800, 2,000, and 5,000 IU/day) in a prospective, randomized pilot trial of 45 patients undergoing Roux-en-Y gastric bypass. Serum 25 hydroxy Vitamin D (25OHD), intact PTH (iPTH), calcium, and urine calcium/creatinine ratios were measured at 6, 12, and 24 months postoperatively. Due to a high dropout rate at 24 months, we focus on the 12-month data. Results  At 12 months, the 800-, 2,000-, and 5,000-IU groups had a mean ± SD increase in 25OHD of 27.5 ± 40.0, 60.2 ± 37.4, and 66.1 ± 42.2 nmol/L, respectively (p = 0.09) with a maximum increase in each group of 87.4, 114.8, and 129.8 nmol/L. Forty-four percent, 78%, and 70% achieved 25OHD levels ≥75 nmol/L (p = 0.38). Results for the 6- and 24-month time points were similar to the 12-month results. Mean weight loss at 24 months of the study was not different among groups (p = 0.52). Serum calcium did not change significantly, and there were no cases of hypercalcemia or sustained hypercalciuria. Conclusions  Higher doses of vitamin D supplementation trend towards higher levels of 25OHD. Vitamin D replacement as high as 5,000 IU /day is safe and necessary in many patients to treat vitamin D deficiency following Roux-en-Y gastric bypass yet is still suboptimal in others.     

Severe obesity and vitamin D deficiency treatment options before bariatric surgery: a randomized clinical trial

BackgroundObesity, which has various complications and co-morbidities, is an epidemic issue worldwide. Vitamin D deficiency (VDD) is a well-known metabolic disorder among patients with severe obesity. While they are good candidates for bariatric surgery, this deficiency can affect the outcome of surgery negatively.ObjectivesThe aim of this study was to compare 3 different VDD treatment strategies for use before bariatric surgery and compare serum vitamin D levels after 7 weeks.SettingsUniversity hospital, Isfahan, Iran.MethodsThis was a single-blinded, randomized clinical trial on 100 patients who were referred for bariatric surgery from 2016 to 2018. Vitamin D (VitD) level was checked before surgery for the patients included in the study, if their VitD level was <30 ng/mL. We rechecked their serum VitD in the 8^th week, after 7 weeks of treatment. The participants were randomly allocated into 3 groups: 33 patients were treated with 50,000 units VitD₃ capsules every week for 7 weeks; 33 patients were treated with a single dose of 300,000 units VitD₃ ampoule; and 34 patients were treated with a combination of a half of the injection dose, followed by the oral capsule for 4 weeks.ResultsNo case was lost during the follow-up time. No significant differences were found among the 3 groups in terms of their age (P = .654), body mass index (P = .434), sex (P = .799), initial 25(OH) VitD level (P = .273), and history of supplement use (P = .45). Mean serum VitD levels were 15.21, 13.16, and 13.37 ng/mL, respectively, before the surgery and reached 32.91, 24.74, and 29.49 ng/mL after 7 weeks of treatment in oral, injection, and combined groups, respectively. Finally, the 7-week oral treatment option had significantly higher levels of VitD (P value = .034).ConclusionVDD treatment with 50,000 units VitD₃ capsule every week for 7 weeks before bariatric surgery yields a higher level of VitD. Based on our findings, injectable supplements are not recommended for VDD treatment.     

Vitamin D Insufficiency in Internal Medicine Residents

Medical residents may be vulnerable to low vitamin D status because of long work hours and lack of sun exposure. We conducted a prospective cohort study to measure serum 25-hydroxyvitamin D concentrations among internal medicine residents, document seasonal variation in vitamin D status, and assess risk factors for inadequate vitamin D stores. Dietary intake of calcium and vitamin D, lifestyle characteristics, and serum concentrations of 25(OH)-vitamin D and intact parathyroid hormone (iPTH) were measured in 35 resident volunteers before and after the winter season. A total of 63–69% of medical residents consumed <400 IU/day of vitamin D; 61–67% consumed <1000 mg/day of calcium. Twenty-five (74%) had lower serum 25(OH)-vitamin D concentrations and 23 (68%) had higher serum iPTH in the spring than in the fall. Nine (26%) residents had serum concentrations of 25(OH)-vitamin D of <20 ng/mL in the fall; and sixteen (47%) in the spring. Seven residents (20%) had serum concentrations of 25(OH)-vitamin D of <20 ng/mL at both time-periods; Eighteen residents (51.4%) had 25(OH)-vitamin D levels of <20 ng/mL for at least one of the time-periods. Medical residents are at risk for hypovitaminosis D, particularly during the winter months and should be aware of the need to supplement their vitamin D stores. Insufficient vitamin D status and inadequate vitamin D intake may have long-term implications for bone health in these individuals. Increased educational efforts to promote healthy dietary and lifestyle choices that allow attainment and maintenance of skeletal health are appropriate in this population.Presented in part at the National Meeting of the Society of General Internal Medicine, (Vancouver, BC, May, 2003).     

Predicting Stricture in Morbidly Obese Patients Undergoing Laparoscopic Roux-en-Y Gastric Bypass: A Logistic Regression Analysis

Gastrojejunostomy stricture after Roux-en-Y gastric bypass occurs in 3 to 27% of morbidly obese patients in the USA. We questioned whether preoperative patient characteristics, including demographic attributes and comorbid disease, might be significant factors in the etiology of stricture. In this study from November 2001 to February 2006 (51 months), at a high-volume bariatric center, of the 1,351 patients who underwent laparoscopic gastric bypass, 92 developed stricture (6.8%). All but two were treated successfully by endoscopic dilation. All patients stopped nonsteroidal anti-inflammatory medications 2 weeks prior to surgery and did not restart them. The operative procedure included the use of a 21-mm transoral circular stapler to create the gastrojejunostomy; the Roux limb was brought retrogastric, retrocolic. In an effort to reduce our center’s stricture rate, late in the study, U-clips used at the gastrojejunostomy were replaced by absorbable sutures, and postoperative H₂ antagonists were added to the treatment protocol. The change to absorbable polyglactin suture proved to be significant, resulting in a lower stricture rate. The addition of H₂ antagonists showed no significant effect. Following the retrospective review of the prospective database, univariate and multivariate logistic regression analyses identified factors associated with the development of stricture. Gastroesophageal reflux disease and age were each shown to be statistically significant independent predictors of stricture following laparoscopic gastric bypass. Presented at the 2006 Annual Meeting of the Society for Surgery of the Alimentary Tract, May 20–24, Los Angeles, CA (poster presentation).     

Efficacy of different doses and time intervals of oral vitamin D supplementation with or without calcium in elderly nursing home residents

Summary The effect of equivalent oral doses of vitamin D3 600 IU/day, 4200 IU/week and 18,000 IU/month on vitamin D status was compared in a randomized clinical trial in nursing home residents. A daily dose was more effective than a weekly dose, and a monthly dose was the least effective. Introduction It is assumed that equivalent daily, weekly or monthly doses of vitamin D3 equally influence vitamin D status. This was investigated in a randomized clinical trial in nursing home residents. Methods The study was performed in ten nursing homes including 338 subjects (76 male and 262 female), with a mean age of 84 (± SD 6.3 years). They received oral vitamin D3 either 600 IU/day, or 4200 IU/week, or 18,000 IU/month or placebo. After 4 months, calcium was added during 2 weeks, 320 mg/day or 640 mg/day or placebo. Outcome: serum levels of 25-hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH) and bone turnover markers. Statistical approach: linear multilevel analysis. Results At baseline, mean serum 25(OH)D was 25.0 nmol/L (SD 10.9), and in 98%, it was lower than 50 nmol/L. After 4 months, mean serum 25(OH)D levels increased to 62.5 nmol/L (after daily vitamin D3 69.9 nmol/L, weekly 67.2 nmol/L and monthly 53.1 nmol/L, P < 0.001 between groups). Median serum PTH levels decreased by 23% (p < 0.001). Bone turnover markers did not decrease. Calcium supplementation had no effect on serum PTH and bone turnover. Conclusion Daily vitamin D was more effective than weekly, and monthly administration was the least effective.     

Prevalence of hypovitaminosis D in elderly women in Italy: clinical consequences and risk factors

In order to evaluate the prevalence, risk factors, and clinical consequences of hypovitaminosis D in elderly Italian women a multicenter study of 43 osteoporosis centers from all regions of Italy was carried out. Study population included 700 women aged 60–80 years in whom blood was taken for 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) measurements. All subjects were also questioned to assess the prevalence of several risk factors for hypovitaminosis D, osteoporotic fractures and activities of daily living (ADL). Values of 25OHD lower than 5 ng/ml were found in 27% of the women and lower than 12 ng/ml in 76%. 25OHD and PTH levels were negatively correlated (r=–0.38, after logarithmic transformation of both variables). 25OHD levels significantly declined with advancing age and number of pregnancies and were positively correlated with educational level (years spent at school), dairy calcium intake, and days spent on holiday by the sea. In a multivariate model including all these variables, the only one that remained significant was the level of education. The lowest age-adjusted 25OH D levels were found in smokers or in women living in central Italy as compared with those living in northern or southern Italy. The mean (±SD) age-adjusted 25OH D values were significantly lower in women who sustained a hip fracture (7.1±2.2 versus 11.0±9.9). Women with low 25OHD levels (<12 ng/ml) had worse scores for ADL and mobility ADL (move outdoors, use stairs, walk at least 400 m, carry a heavy object). Vitamin D deficiency is extremely common among elderly Italian women. Women with lower educational level, living in central Italy, smokers or with lower intake of dairy products are at greater risk. Hypovitaminosis D is associated with worsening of the ability to perform activities of daily living and higher hip fracture prevalence. This finding should lead to an urgent population-based strategy to remedy this condition.Local participants in the study (name and Italian town of study site): S. Adami, Verona; M. Bevilacqua, Milano; E.M. Bibolotti, Piombino; F. Cantini, Prato; S. Coaccioli, Terni; R. Conca, Milano; D. Costi, Parma; G. D'Avola, Catania; O. Di Munno, Pisa; M. Ferraris, Vercelli; P. Filipponi, Perugia; C.M. Francucci, Ancona; G. Gandolini, Milano; S. Gatto, Napoli; P. Gigliotti, Cosenza; T. Gismondi, Bari; S. Gnudi, Bologna; E. Grimaldi, Trieste; G. Isaia, Torino; G. La Montagna, Napoli; G. Lojacono, Bari; R.V. Lovato; F. Luparelli, Taranto; U. Martorana, Palermo; A. Mathieu, Cagliari; D. Maugeri, Catania; S. Minisola, Roma; S. Miozzi, Roma; G. Occhipinti, Livorno; R. Pellerito, Torino; D. Policicchio, Avellino; M. Portigliatti Barbos, Torino; G.B. Rini, Palermo; G. Rosa, Napoli; D. Schinella, Pordenone; M. Sfrappini, Tronto; P. Simonetta, Reggio Calabria; L. Sinigaglia, Milano; S. Stisi, Benevento; A. Tarroni, Rimini; F. Trotta, Ferrara; F. Versace, Savona     

Vitamin D Deficiency: A Common Occurrence in Both High-and Low-energy Fractures

As a consequence of newly elevated standards for normal vitamin D levels, there is a renewed interest in vitamin D insufficiency and deficiency (<32 and <20 ng/ml, respectively) in the orthopedic patient population. This study tests the hypothesis that vitamin D insufficiency is comparably prevalent among both high- and low-energy fracture patients. A retrospective analysis of the medical records for 44 orthopedic trauma in-patients with non-vertebral fractures was conducted from June 1, 2006 to February 1, 2007. The obtained data included a 25-hydroxyvitamin D level, age, gender, and reason for admission; high-energy vs. low-energy fracture. Vitamin D insufficiency, 25(OH)D <32 ng/ml, was found in 59.1% of the patients. Significantly, more women (75%) than men (40%) were vitamin D insufficient among all fracture patients and specifically among high-energy fractures, 80% women insufficient vs. 25% men insufficient. In women, both high- and low-energy fractures present with vitamin D insufficiency (80% of high-energy fractures and 71.4% of low-energy fractures). In men, the mean vitamin D level was lower for low-energy fractures (16 ng/ml) compared to high-energy fractures (32 ng/ml). In addition, men with low-energy fractures were significantly older than men with high-energy fractures and women with low-energy fractures were also older. Statistically, more vitamin D insufficiency is seen in women and our results are consistent with the gender difference seen in the general population. Even among younger men who sustain a high-energy fracture, 25% are vitamin D insufficient. Women with fractures regardless of age or fracture energy level have low vitamin D levels. Levels of 25(OH)D should be measured in all orthopedic trauma patients and the American Society for Bone and Mineral Research and National Osteoporosis Foundation currently recommend that vitamin D levels should be corrected.     

Prevalence of Vitamin D Insufficiency in an Adult Normal Population

The vitamin D status of a general adult urban population was estimated between November and April in 1569 subjects selected from 20 French cities grouped in nine geographical regions (between latitude 43° and 51° N). Major differences in 25-hydroxyvitamin D (25(OH)D) concentration were found between regions, the lowest values being seen in the North and the greatest in the South, with a significant ‘sun’ effect (r = 0.72; p = 0.03) and latitude effect (r = -0.79; p = 0.01). In this healthy adult population, 14% of subjects exhibited 25(OH)D values ≤ 30 nmol/l (12 ng/ml), which represents the lower limit (< 2 SD) for a normal adult population measured in winter with the same method (RIA Incstar). A significant negative correlation was found between serum intact parathyroid hormone (iPTH) and serum 25(OH)D values (p < 0.01). Serum iPTH held a stable plateau level at 36 pg/ml as long as serum 25(OH)D values were higher than 78 nmol/l (31 ng/ml), but increased when the serum 25(OH)D value fell below this. When the 25(OH)D concentration became equal to or lower than 11.3 nmol/l (4.6 ng/ml), the PTH values reached the upper limit of normal values (55 pg/ml) found in vitamin D replete subjects. These results showed that in French normal adults living in an urban environment with a lack of direct exposure to sunshine, diet failed to provide an adequate amount of vitamin D. It is important to pay attention to this rather high prevalence of vitamin D insufficiency in the general adult population and to discuss the clinical utility of winter supplementation with low doses of vitamin D.     

Inhibition of C-Reactive Protein in Morbidly Obese Patients After Laparoscopic Sleeve Gastrectomy

BACKGROUND: Obesity is considered a low-grade chronic inflammatory condition as reflected by increased C-reactive protein (CRP) levels. Inflammation is emerging as a predictor of cardiovascular disease and it may be a precursor of the metabolic syndrome. Bariatric surgery is commonly performed as a treatment for morbid obesity offering significant reductions in premature myocardial infarction. Laparoscopic sleeve gastrectomy (LSG) is a relatively new bariatric procedure that is currently used as a definitive procedure for weight loss. The aim of this study is to assess the impact of sleeve gastrectomy on CRP levels. METHODS: This study is part of an ongoing, prospective, cohort study to evaluate LSG impact on iron indices. CRP levels were compared preoperatively and 6 months after surgery. Similarly, demographics including body mass index and excess weight were also compared at these same study points. Data were analyzed using Student paired t test and Pearson product moment correlation analysis. RESULTS: Twenty-nine morbidly obese patients were included. There was significant decrease in body mass index (BMI) between the preoperative and 6-month period (50.9 +/- 13.2 and 35.1 +/- 6.85, respectively; P < 0.001). Also CRP levels were statistically significantly lower at 6 months after surgery (preoperative 12.3 +/- 7.53 mg/L and postoperative 5.6 +/- 4.2 mg/L. P < 0.0001). The significant weight loss as reflected by change in BMI was correlated with the difference between preoperative and postoperative CRP levels. CONCLUSIONS: Massive weight loss in morbidly obese patients induced by LSG causes a significant decrease in CRP levels, which could reduce the risk of cardiovascular diseases in these patients.     

Vitamin D: A Necessity for Children and Adolescents in Greece

Children and adolescents with the high bone turnover comprise a high risk population for vitamin D insufficiency. A sample of 178 clinically healthy children aged 3 to 18 years who came from public schools and lived in North West of Greece participated in the study. They were grouped into three age groups (I: 3–10, II: 11–14 and III: 15–18 years of age). Blood samples were taken during winter and summer months for determining calciotropic hormones, calcium, phosphate and biochemical markers of bone synthesis. A high percentage (47%) of the subjects aged 15–18 years was found to have 25OHD <10 ng/ml in winter but much less (13–14%) of the younger ages (13–14 years), while in the summer they were all >10 ng/ml. The prevalence was even higher in the girls of the older group accompanied by lower Pi concentrations again in winter (win:1.19±0.03, sum:1.93±0.03 mmol/l, p < 0.001). The 24,25(OH)₂D levels were changing in parallel to 25OHD, but again in the older subjects, during winter, they were by 2/3 lower than the summer ones (0.73±0.10 vs. 2.41±0.20 ng/ml, p < 0.001). No significant differences were found between seasons and groups in the 1,25(OH)₂D levels. The biochemical markers of bone synthesis, osteocalcin (OC) and total alkaline phosphatase (ALP), were found significantly lower in the girls of the older group both in winter and summer respectively.Even in a sunny country like Greece the adolescents living in an urban area are in high risk for vitamin D deficiency during winter. Supplementation with vitamin D of milk, of popular beverages and perhaps some foods would be of help.     

Muscle Force and Force Control After Weight Loss in Obese and Morbidly Obese Men

BACKGROUND: Decrease in fat mass and fat-free mass have been observed with weight loss induced by a dietary intervention or surgery. There are concerns that fat-free mass decrease could have some negative functional consequences. The aim of this study was to examine how weight loss affects strength and force control in obese and morbidly obese men. METHODS: Weight loss was obtained in obese individuals by a hypocaloric diet program until resistance to lose fat and in morbidly obese individuals by bariatric surgery. Maximal force was measured for upper and lower limb and the ability to maintain 15% and 40% of that force. These measures were taken at baseline, in those dieting once resistant to weight loss and 1 year after surgery for those operated on. Normal weight individuals used for control were evaluated twice (6 to 12 months apart). RESULTS: At baseline, there was no significant difference between groups for maximal forces and capabilities to maintain force levels. Weight loss averaged 11.1% of the initial body weight after dieting and 46.3% 1 year after surgery. At the same time, there was for the lower limb a loss of 10.1% in maximal force after dieting and 33.5% after surgery. For the upper limb, there was no change in maximal force after dieting whereas a decrease of 14.4% was observed after surgery. When transformed in force related to body weight, there was no change in relative force for the lower limb after dieting whereas an increased relative force after surgery. There was no significant difference for the ability for maintaining force levels. CONCLUSION: Despite a large force loss, particularly for the lower limbs in morbidly obese individuals after surgery, this loss is relatively well tolerated because the relation between force and body weight is even improved and the ability to maintain that force is preserved.     

Vitamin D, PTH, and the Metabolic Syndrome in Severely Obese Subjects

Objective The objective of this study was to evaluate the association between the metabolic syndrome (MS) and vitamin D [25(OH)D] or parathyroid hormone (PTH) levels in severely obese subjects. Research Design and Methods Cross-sectional study in 298 severely obese patients [body mass index (BMI) 46.7 ± 5.3 kg/m²; women/men, 70.4/29.6%; age 42.9 ± 10.6 years]. Logistic and stepwise regression models were fit to estimate the odds for the MS (revised ATPIII criteria) and each of its individual components across quartiles of 25(OH)D and PTH after adjusting for age (years), gender, BMI, %FM, and season of blood sample collection. Results Insufficient 25(OH)D and elevated PTH plasma levels were encountered, respectively, in 64.3 and 47.4% of the studied subjects. The prevalence of MS was 79.5%. In the unadjusted analysis, those in the highest quartile of 25(OH)D were less likely to present the MS [0.42 (95% CI 0.19–0.96)], hyperglycemia [0.47, (0.24–0.92)], high triglycerides [0.48 (0.25–0.95)], low HDL-cholesterol [1.51 (0.76–2.98)], and high blood pressure [0.35 (0.16–0.77)]. Nonetheless, these odds ratios lost significance after adjustment for age, gender, BMI, fat mass, and season. Backward stepwise regression analysis showed that only male gender [2.66 (1.16–6.10)] and age [1.07 (1.03–1.10)] were predictive variables for the MS. We did not find an association between the PTH quartiles and the MS or its individual components. Conclusions Our data are consistent with previous reports on the high prevalence of alterations in calcium metabolism in severely obese subjects. However, our data do not support an independent contribution of 25(OH)D or PTH in the pathogenesis of the MS in severely obese subjects.     

Laparoscopic Sleeve Gastrectomy with Minimal Morbidity Early Results in 120 Morbidly Obese Patients

Background  In recent years, laparoscopic sleeve gastrectomy (LSG) as a single-stage procedure for the treatment of morbid obesity is becoming increasingly popular. Of continuing concern are the rate of postoperative complications and the lack of consensus as to surgical technique. Methods  A prospective study assessment was made of 120 consecutive morbidly obese patients with body mass index (BMI) of 43 ± 5 (30 to 63), who underwent LSG using the following technique: (1) division of the vascular supply of the greater gastric curvature and application of the linear stapler-cutter device beginning at 6–7 cm from the pylorus so that part of the antrum remains; (2) inversion of the staple line by placement of a seroserosal continuous suture close to the staple line; (3) use of a 48 Fr bougie so as to avoid possible stricture; (4) firing of the stapler parallel to the bougie to make the sleeve as narrow as possible and prevent segmental dilatation. Results  Intraoperative difficulties were encountered in four patients. There were no postoperative complications—no hemorrhage from the staple line, no anastomotic leakage or stricture, and no mortality. In 20 patients prior to the sleeve procedure, a gastric band was removed. During a median follow-up of 11.7 months (range 2–31 months), percent of excess BMI lost reached 53 ± 24% and the BMI decreased from 43 ± 5 to 34 ± 5 kg/m². Patient satisfaction scoring (1–4) at least 1 year after surgery was 3.6 ± 0.8. Conclusions  The good early results obtained with the above-outlined surgical technique in 120 consecutive patients undergoing LSG indicate that it is a safe and effective procedure for morbid obesity. However, long-term results are still pending.     

Seasonal Variation in the Deficiency of 25-Hydroxyvitamin D3 in Mildly to Extremely Obese Subjects.

Background  Vitamin D deficiency is a common finding in obese subjects even before any bariatric operation. However, most previous studies reporting on high rates of vitamin D deficiency in obese subjects have not systematically controlled for seasonal variations. Furthermore, the existence of seasonal variation in serum 25-hydroxyvitamin D₃ levels has not been well documented in obese subjects so far. Methods  Serum 25-hydroxyvitamin D₃ levels were measured in 248 obese subjects (body mass index: range, 30.1–68.9 kg/m²). Fat mass was determined using standard bioelectrical impedance analysis. Results  Serum 25-hydroxyvitamin D₃ levels decreased with the increasing body mass index and fat mass (both P < 0.001) and showed a marked variation across the seasons of the year (P < 0.001), which was not affected by the degree of obesity. According to the variation in absolute levels, the prevalence of vitamin D deficiency (<50 nmol/l) was 3.8-fold higher during winter than during summer (91.2% vs. 24.3%; P < 0.001). Conclusion  Data show a marked seasonal variation in absolute serum 25-hydroxyvitamin D₃ concentrations and prevalence of vitamin D deficiency in subjects with mild to extreme obesity. Considering the increasing number of studies reporting on vitamin D deficiency in obesity, the present finding points to season as a crucial factor that should not be neglected when assessing serum levels of this vitamin in obese subjects.     

Obesity,Bariatric Surgery,and Vitamin D

The high prevalence of obesity is a worldwide problem associated with multiple comorbidities, including cardiovascular diseases. Vitamin D deficiency with secondary hyperparathyroidism is common in obese individuals and can be aggravated after bariatric surgery. Moreover, there is no consensus on the optimal supplementation dose of vitamin D in postbariatric surgical patients. We present new data on the variability of 25(OH)D response to supplementation in postmenopausal obese women. It is important to recognize and treat vitamin D deficiency before bariatric surgery to avoid postoperative complications, such as metabolic bone disease with associated high fracture risk. The objective of this article is to discuss the bone metabolism consequences of vitamin D deficiency after bariatric surgery.     

Vitamin D insufficiency and the blunted PTH response in established osteoporosis: the role of magnesium deficiency

Introduction Vitamin D insufficiency is common, however within individuals, not all manifest the biochemical effects of PTH excess. This further extends to patients with established osteoporosis. The mechanism underlying the blunted PTH response is unclear but may be related to magnesium (Mg) deficiency. The aims of this study were to compare in patients with established osteoporosis and differing degrees of vitamin D and PTH status : (1) the presence of Mg deficiency using the standard Mg loading test (2) evaluate the effects of Mg loading on the calcium-PTH endocrine axis (3) determine the effects of oral, short term Mg supplementation on the calcium-PTH endocrine axis and bone turnover. Methods 30 patients (10 women in 3 groups) were evaluated prospectively measuring calcium, PTH, Mg retention (Mg loading test), dietary nutrient intake (calcium, vitamin D, Mg) and bone turnover markers (serum CTX & P1CP). Multivariate analysis controlling for potential confounding baseline variable was undertaken for the measured outcomes. Results All subjects, within the low vitamin D and low PTH group following the magnesium loading test had evidence of Mg depletion [mean(SD) retention 70.3%(12.5)] and showed an increase in calcium 0.06(0.01) mmol/l [95% CI 0.03, 0.09, p=0.007], together with a rise in PTH 13.3 ng/l (4.5) [95% CI 3.2, 23.4, p=0.016] compared to baseline. Following oral supplementation bone turnover increased: CTX 0.16 (0.06) mcg/l [95%CI 0.01, 0.32 p=0.047]; P1CP 13.1 (5.7) mcg/l [95% CI 0.29, 26.6 p=0.049]. In subjects with a low vitamin D and raised PTH mean retention was 55.9%(14.8) and in the vitamin replete group 36.1%(14.4), with little change in both acute markers of calcium homeostasis and bone turnover markers following both the loading test and oral supplementation. Conclusions This study confirms that in patients with established osteoporosis, there is also a distinct group with a low vitamin D and a blunted PTH level and that Mg deficiency (as measured by the Mg loading test) is an important contributing factor. Funding Sources This work was supported by a Research and Development (R & D ) grant, Nottingham City Hospital and an educational grant from Lambert’s Pharmaceuticals Ltd. An erratum to this article can be found at     

Prevalence of vitamin D depletion among subjects seeking advice on osteoporosis: a five-year cross-sectional study with public health implications

Summary We assessed vitamin D nutritional status in unselected consecutive patients seeking advice on osteoporosis. The prevalence of vitamin D depletion ranged from 15–72% depending upon the cut-off levels used for serum 25-hydroxyvitamin D, and the prevalence did not change over the 5 years of the study. Introduction Vitamin D depletion is a significant public health problem and has been studied in different populations using different cut-off levels, but the optimal level is yet to be established. Methods In a cross-sectional study of 2924 patients seen for osteoporosis advice we determined the prevalence of vitamin D depletion, as assessed by 25-hydroxyvitamin D (25-OHD), using three different cut-off levels stratified by gender, race and the year of the study over 5 years. Results Mean age was 68.3 ± 10.0 years; 90% women and 88% white. Mean 25-OHD level was 24.6 ± 10 ng/ml and mean PTH was 48.4 ± 32 pg/ml. The prevalence of vitamin D depletion was 15% with a cut-off level of <15 ng/ml, and rose to 32% and 72% with cut-off levels <20 ng/ml and <30 ng/ml, respectively. The prevalence was higher in men and blacks and remained constant over 5 years, regardless of the cut-off level. The expected inverse relationship between 25-OHD and PTH was observed irrespective of gender or ethnicity. Conclusions The prevalence of vitamin D depletion in patients seeking advice for osteoporosis is high and did not change over the 5 years of the study.     

High Prevalence of Vitamin D Insufficiency in Southern Chinese Renal Transplant Recipients

Vitamin D deficiency is common globally. There is evidence that vitamin D status may be related to immune function and cardiovascular disease. The vitamin D status of Chinese kidney transplant recipients has never been investigated. We performed a cross-sectional study and measured the level of 25-hydroxyvitamin D [25(OH)D] in 94 Chinese renal transplant recipients with stable allograft function. Vitamin D deficiency and insufficiency were detected in 43.6% and 54.2% of patients, respectively. About 53.2% of the patients also had elevated parathyroid hormone (PTH) levels. The level of 25(OH)D was lower in kidney transplant recipients compared with healthy controls matched for age and sex (52.5 ± 15.6 nmol/L vs. 57.5 ± 19.0 nmol/L, p = 0.05), but the level of serum creatinine was higher in kidney transplant recipients (120.3 ± 48.5 μmol/L and 78.3 ± 15.3 μmol/L, p < 0.01). The level of 25(OH)D was negatively correlated with that of PTH (p = 0.001). The latter was associated with serum creatinine (p = 0.001) and duration of dialysis (p = 0.001). Patients with a history of acute rejection showed lower levels of 25(OH)D (45.3 ± 11.9 nmol/L vs. 54.2 ± 16.0 nmol/L, p = 0.003). We conclude that vitamin D deficiency is prevalent among Chinese renal transplant recipients. In view of the potential immunomodulatory effect of vitamin D, the relationship between vitamin D level and rejection and the effect of vitamin D supplementation in renal transplant recipients warrant further investigations.     

Prevalence of and Risk Factors for Hypovitaminosis D in Patients with Rotator Cuff Tears

BackgroudIt has been reported that vitamin D may play an important role in rotator cuff tears. However, there has been limited information about the prevalence of and risk factors for hypovitaminosis D in patients with rotator cuff tears. Therefore, the purpose of current study was to investigate the prevalence of and risk factors for hypovitaminosis D in patients with rotator cuff tears.MethodsOne hundred seventy-six patients (age, 61.9 ± 8.90 years) who underwent arthroscopic rotator cuff repair for a full-thickness tear were enrolled in this retrospective study. Preoperative serum vitamin D levels (25-hydroxyvitamin D) were measured. Hypovitaminosis D was defined as a serum concentration of 25-hydroxyvitamin D < 20 ng/mL. We investigated whether age, sex, height, weight, body mass index, bone mineral density, alcohol consumption, smoking status, and outdoor occupation were associated with hypovitaminosis D.ResultsThe prevalence of hypovitaminosis D in patients with rotator cuff tears was 44.3% (78/176). The mean serum concentration of 25-hydroxyvitamin D of total patients was 24.7 ± 13.7 ng/mL. A higher serum level of vitamin D was significantly associated with older age (p < 0.001). Young age was an independent risk factor for hypovitaminosis D. The prevalence of hypovitaminosis D was also lower in patients with an outdoor occupation than in those with an indoor occupation (19.0% vs. 31.4%, p = 0.001).ConclusionsThe prevalence of hypovitaminosis D in patients with rotator cuff tears was 44.3%. Age had a significant positive correlation with the serum concentration of 25-hydroxyvitamin D. Young age and indoor working were independent risk factors for hypovitaminosis D in patients with rotator cuff tears. Therefore, the possibility of hypovitaminosis D should be considered for young and indoor working patients who have rotator cuff tears.