Does Vitamin D Status Affect the Attainment of In-Hospital Functional Milestones After Total Hip Arthroplasty?

Our study aims to identify the prevalence of low vitamin D status in patients undergoing total hip arthroplasty (THA) and to evaluate the association between serum vitamin D level and the attainment of in-hospital functional milestones. We collected data from patients who underwent THA and had preoperative serum vitamin D (serum 25-hydroxy vitamin D) levels measured. From 200 patients, 79 (39.5%) had low serum vitamin D (serum 25-hydroxy vitamin D <32 ng/mL). There were no associations between serum vitamin D level and the attainment of in-hospital functional milestones as well as length of hospital stay or perioperative complications after THA. Because low vitamin D status did not compromise the short-term functional outcomes after THA, surgery need not be delayed, but low vitamin D levels should be corrected once identified.     

Metal Ion Levels in Total Hip Arthroplasty Versus Hip Resurfacing

Recent studies suggest that the tapered interface between stem and femoral head may be a substantial source of cobalt and chromium ion release after metal-on-metal (MOM) total hip arthroplasty (THA). This study compared patient ion levels after MOM hip resurfacing (HR) and MOM THA performed with identical acetabular components. 110 HRs were compared with 22 THAs. All had well-oriented components, unilateral implants, and serum ion studies beyond one year post-operatively. The HR group’s median cobalt value was 1.11 μg/L vs. 2.86 μg/L for the THA patients. The HR group’s median chromium value was 1.49 μg/L vs. 2.94 μg/L for THA. Significantly higher THA ion levels suggest a source of ions other than the MOM bearing itself.     

High prevalence of vitamin K and D deficiency and decreased BMD in inflammatory bowel disease

Summary  Vitamin K and D deficiency and decreased bone mineral density (BMD) were highly prevalent in patients with inflammatory bowel disease (IBD), especially Crohn’s disease (CD). Dietary intakes of these vitamins, however, were above the Japanese adequate intakes in IBD patients, suggesting that malabsorption is the basis for hypovitaminosis K and D and decreased BMD. Introduction  We have studied the possible involvement of vitamin K and D deficiency in the pathogenesis of decreased BMD in IBD. Methods  Seventy patients with IBD were evaluated for their BMD; plasma levels of vitamin K; phylloquinone (PK), menaquinone-7 (MK-7), and 25OH-D; serum PTH, protein induced by vitamin K absence (PIVKA-II), and undercarboxylated osteocalcin (ucOC) levels; and their food intake. Results  Compared with ulcerative colitis (UC) patients, CD patients had significantly lower plasma vitamin K and 25OH-D concentrations; significantly higher serum levels of PTH, PIVKA-II, and ucOC; and significantly lower BMD scores at almost all measurement sites. More IBD patients were vitamin K deficient in bone than in liver. Multiple regression analyses revealed that low plasma concentrations of vitamin K and 25OH-D were independent risk factors for low BMD and that they were associated with the patients’ fat intake, but not with their intake of these vitamins. Conclusion  IBD patients have high prevalence of decreased BMD and vitamin K and D deficiency probably caused by malabsorption of these vitamins.     

Low serum levels of 25-hydroxy vitamin D in adults affected by thalassemia major or intermedia

Adult thalassemic patients have reduced bone mass due to disturbances in several different mechanisms affecting bone turnover. To determine if vitamin D deficiency contributes to the low bone mass of adult thalassemic subjects, we studied serum 25-OH-vitamin D levels in 90 patients (age ranging between 21 and 48 years) affected with thalassemia major (TM) and 35 (age 21–56 years) with thalassemia intermedia (TI).

TM patients had been receiving regular transfusions from the age of 2 years and had increased serum ferritin, glutamic oxalacetic transaminase, glutamic piruvic transaminase as well as low bone density (L1–L4 Z score −2.07 ± 0.2). TI patients did not receive transfusions, but their ferritin levels were increased as well (520.3 ± 138,1). 8 TM patients (10.1%) and 4 TI (11.4%) had serum 25-OH-vitamin D less than 10.4 ng/ml and were considered presenting an absolute deficiency of vitamin D. Mean 25-OH-vitamin D was significantly (P < 0.01) lower in both TM and TI patients (20.3 ± 0.7 ng/ml and 20.9 ± 2.3 ng/ml, respectively) than in 100 healthy control subjects of similar age (25.2 ± 1 ng/ml). 1,25-OH-vitamin D levels were in the normal–lower levels (45.15 ± 1.5 mg/dl), while 24 H urinary calcium was below the normal range (15.75 mg/dl). In TM patients, the 25-OH-vitamin D levels correlated negatively with age (P < 0.05) and with serum ferritin (P < 0.05). TM and TI patients with low 25-OH-vitamin D levels (<17.8 ng/ml) presented higher serum ferritin levels (P < 0.01) and higher PTH (P < 0.05) compared to those with normal vitamin D. Moreover, TM patients with low 25-OH-vitamin D levels were significantly older (P < 0.05) and had higher GPT (P < 0.05) than patients with normal vitamin D.

In conclusion, calcium metabolism is frequently impaired in adult thalassemic patients. An early and effective medical treatment should be taken in consideration by the clinician in order to improve the bone health in these patients.     

Vitamin B12 Deficiency In Spinal Cord Injury: A Retrospective Study

Abstract

Background/Objective: Vitamin B12 (or cobalamin) deficiency is well known in geriatric patients, but not in those with spinal cord injury (SCI) . This retrospective study describes vitamin B1 2 deficiency in SCI.

Methods: This study utilized a retrospective chart review of patients with SCI who had received serum vitamin B1 2 testing over the last 1 0 years.

Results: Probable vitamin B1 2 deficiency was noted in 1 6 patients with SCI. Twelve patients had subnormal serum vitamin B12 levels (< 220 pg/ml), whereas 4 patients had low-normal vitamin B12 levels (< 300 pg/ml) with neurologic and/or psychiatric symptoms that improved following vitamin B1 2 replacement. Classic findings of paresthesias and numbness often were not evident; such findings likely were masked by the pre-existing sensory impairment caused by SCI. Of the 1 6 SCI patients, 7 were ambulatory; 4 of the 7 presented with deterioration of gait. In addition, 3 of the 1 6 SCI patients presented with depression and fatigue, 2 had worsening pain , 2 had worsening upper limb weakness, and 2 had memory decline. Of the 1 2 patients with subnormal serum vitamin B12 levels, 6 were asymptomatic. Classic laboratory findings of low serum vitamin B1 2 , macrocytic red blood cell indices, and megaloblastic anemia were not always present. Anem ia was identified in 7 of the 1 6 patients and macrocytic red blood cells were found in 3 of the 1 6 patients. Only 1 of the 1 6 SCI patients had a clear pathophysiologic mechanism to explain the vitamin B12 deficiency (ie, partial gastrectomy); none of the patients were vegetarian. Twelve of the SCI patients appeared to experience clinical benefits from cyanocobalamin replacement (some patients experienced more than 1 benefit), including reversal of anemia (5 patients), improved gait (4 patients), improved mood (3 patients), improved memory (2 patients), reduced pain (2 patients) , strength gain (1 patient), and reduced numbness (1 patient).

Conclusion: It is recommended that physicians consider vitamin B1 2 deficiency in their patients with SCI , particularly in those with neurologic and/ or psychiatric symptoms. These symptoms often are reversible iftreatment is initiated early.     

The Importance Of Nutrition In The Care Of Persons With Spinal Cord Injury

Abstract

Background/Objective: Vitamin B12 (or cobalamin) deficiency is well known in geriatric patients, but not in those with spinal cord injury (SCI) . This retrospective study describes vitamin B1 2 deficiency in SCI.

Methods: This study utilized a retrospective chart review of patients with SCI who had received serum vitamin B1 2 testing over the last 1 0 years.

Results: Probable vitamin B1 2 deficiency was noted in 1 6 patients with SCI. Twelve patients had subnormal serum vitamin B12 levels (< 220 pg/ml), whereas 4 patients had low-normal vitamin B12 levels (< 300 pg/ml) with neurologic and/or psychiatric symptoms that improved following vitamin B1 2 replacement. Classic findings of paresthesias and numbness often were not evident; such findings likely were masked by the pre-existing sensory impairment caused by SCI. Of the 1 6 SCI patients, 7 were ambulatory; 4 of the 7 presented with deterioration of gait. In addition, 3 of the 1 6 SCI patients presented with depression and fatigue, 2 had worsening pain , 2 had worsening upper limb weakness, and 2 had memory decline. Of the 1 2 patients with subnormal serum vitamin B12 levels, 6 were asymptomatic. Classic laboratory findings of low serum vitamin B1 2 , macrocytic red blood cell indices, and megaloblastic anemia were not always present. Anem ia was identified in 7 of the 1 6 patients and macrocytic red blood cells were found in 3 of the 1 6 patients. Only 1 of the 1 6 SCI patients had a clear pathophysiologic mechanism to explain the vitamin B12 deficiency (ie, partial gastrectomy); none of the patients were vegetarian. Twelve of the SCI patients appeared to experience clinical benefits from cyanocobalamin replacement (some patients experienced more than 1 benefit), including reversal of anemia (5 patients), improved gait (4 patients), improved mood (3 patients), improved memory (2 patients), reduced pain (2 patients) , strength gain (1 patient), and reduced numbness (1 patient).

Conclusion: It is recommended that physicians consider vitamin B1 2 deficiency in their patients with SCI , particularly in those with neurologic and/ or psychiatric symptoms. These symptoms often are reversible iftreatment is initiated early.     

Influence of Season,Ethnicity, and Chronicity on Vitamin D Deficiency in Traumatic Spinal Cord Injury

Background:

Inadequate levels of vitamin D increase the risk of osteoporosis, a highly prevalent condition in patients with traumatic spinal cord injury (SCI). Reduced sunlight and dark skin further contribute to low vitamin D levels.

Objectives:

To compare serum 25-hydroxy vitamin D [vitamin D25(OH)] levels in acute and chronic SCI and to explore seasonal and ethnic differences among patients with acute and chronic SCI.

Patients/Methods:

Patients (N  =  96) aged 19 to 55 years with C3-T10 motor complete SCI participated. Acute SCI was 2 to 6 months after injury, whereas chronic SCI was at least 1 year from injury. Serum vitamin D25(OH), calcium, and parathyroid hormone were drawn during summer or winter months. Vitamin D deficiency (<13 ng/mL), insufficiency (<20 ng/mL), and subtherapeutic (<32 ng/mL) levels were compared for all groups. A 3-way analysis of covariance was adopted to determine significant main effects of season, chronicity, and ethnicity. Interactions between season and chronicity, season and ethnicity, and chronicity and ethnicity were evaluated. Evaluation of a 3-way interaction among season, chronicity, and ethnicity was completed.

Results:

In summer, 65% of patients with acute SCI and 81% of patients with chronic SCI had subtherapeutic vitamin D levels, whereas in winter, 84% with acute SCI and 96% with chronic SCI had vitamin D25(OH) (<32ng/mL). Lower vitamin D25(OH) levels were observed in African Americans relative to whites. Significant main effects were noted for season (P  =  0.017), chronicity (P  =  0.003), and ethnicity (P < 0.001). However, interactions between 2 or more factors were not found.

Conclusions:

Vitamin D insufficiency and deficiency are found in the majority of patients with chronic SCI and in many with acute SCI. Initial screening for serum vitamin D25(OH) levels should be performed early in rehabilitation. Periodic monitoring in the chronic setting is highly recommended.     

Severe vitamin D deficiency in chronic renal failure patients on peritoneal dialysis

The aim of this study was to evaluate the prevalence of vitamin D deficiency in chronic renal failure (CRF) patients on peritoneal dialysis (PD) and to correlate the findings with various demographic and renal osteodystrophy markers. METHOD: This cross-sectional, multicenter study was carried out in 273 PD patients with a mean age of 61.7 +/- 10.9 years and mean duration of PD 3.3 +/- 2.2 years. It included 123 female and 150 male patients from 20 centers in Greece and Turkey, countries that are on the same latitude, namely, 36-42 degrees north. We measured 25(OH)D3 and 1.25(OH)2D3 levels and some other clinical and laboratory indices of bone mineral metabolism. RESULTS: Of these 273 patients 92% (251 patients) had vitamin D deficiency i.e. serum 25(OH)D3 levels less than 15 ng/ml, 119 (43.6%) had severe vitamin D deficiency i.e., serum 25(OH)D3 levels, less than 5 ng/ml, 132 (48.4%) had moderate vitamin D deficiency i.e., serum 25(OH)D3 levels, 5-15 ng/ml, 12 (4.4%) vitamin D insufficiency i.e., serum 25(OH)D3 levels 15 - 30 ng/ml and only 10 (3.6%) had adequate vitamin D stores. We found no correlation between 25(OH)D3 levels and PTH, serum albumin, bone alkaline phosphatase, P, and Ca x P. In multiple regression analyses, the independent predictors of 25(OH)D3 were age, presence of diabetes (DM-CRF), levels of serum calcium and serum 1.25(OH)2D3. CONCLUSION: We found a high prevalence (92%) of vitamin D deficiency in these 273 PD patients, nearly one half of whom had severe vitamin D deficiency. Vitamin D deficiency is more common in DM-CRF patients than in non-DM-CRF patients. Our findings suggest that these patients should be considered for vitamin D supplementation.     

Vitamin D supplementation improves response to antiviral treatment for recurrent hepatitis C

In immune‐competent patients, higher vitamin D levels predicted sustained viral response (SVR) following interferon (INF) and ribavirin therapy for chronic hepatitis C. This study aimed to verify the influence of vitamin D serum levels and/or vitamin D supplementation in predicting SVR rates for recurrent hepatitis C (RHC). Forty‐two consecutive patients were treated for RHC with combination therapy with INF‐α and ribavirin for 48 weeks. Vitamin D serum levels were measured in all patients before antiviral therapy. In 15 patients oral vitamin D3 supplementation was administered to avoid further bone loss. SVR was observed in 13 patients; it was achieved in 1/10 severely vitamin D deficient (≤10 ng/ml) patients, in 6/20 deficient (>10 and ≤20 ng/ml) and in 6/12 with near normal (>20 ng/ml) 25‐OH vitamin D serum levels (P < 0.05). Cholecalciferol supplementation, in the presence of a normal or near normal baseline vitamin D concentration, (improvement of chi‐square P < 0.05, odds ratio 2.22) and possessing a genotype other than 1 (improvement of chi‐square P < 0.05, odds ratio 3.383) were the only variables independently associated to SVR. In conclusion, vitamin D deficiency predicts an unfavourable response to antiviral treatment of RHC. Vitamin D supplementation improves the probability of achieving a SVR following antiviral treatment.     

Oversized Cups as a Major Risk Factor of Postoperative Pain After Total Hip Arthroplasty

After total hip arthroplasty (THA) some patients have persistent postoperative pain (POP). Some of these POP are anterior and are caused by an anterior iliopsoas impingement (AIPI). We have hypothesized that oversized implanted cups could be responsible for POP and especially AIPI. We screened 237 patients who had a primary THA and compared the size difference (ΔS) between the native femoral head and the implanted cup, in patients with and without POP. Median ΔS was 2 mm [− 6; 11 mm] and patients with POP had a significantly increased ΔS (P < 0.0001). The threshold above which pain was significantly more frequent was ΔS ≥ 6 mm. Odds ratio was 14.4 for POP and 26 for AIPI pain when ΔS ≥ 6 mm.     

Vitamin D status and its relationship with bone mineral density in healthy Asian Indians

Synthesis of vitamin D takes place in the skin under the effect of sunlight. The Indian subcontinent is situated between 8.4° N and 37.6° N latitudes and has adequate sunshine throughout the year. Thus, it has been presumed that Indians are vitamin D sufficient. We measured serum 25-hydroxy vitamin D [25(OH)D] (n=92) and 1,25-dihydroxy vitamin D [1, 25(OH)₂D] (n=65) levels in healthy hospital staff, using ¹²⁵I radioimmunoassay. Serum intact parathyroid hormone (PTH) concentration was estimated by immunoradiometric assay. Bone mineral density was estimated using a dual energy X-ray absorptiometer (Hologic^R QDR 4500A). Using a serum 25(OH)D level of 15 ng/ml as a cutoff, 66.3% (61/92) of the subjects were found to be vitamin D deficient. Of these, 20.6% (19/92) subjects had severe vitamin D deficiency (<5 ng/ml), 27.2% (25/92) had moderate vitamin D deficiency (5–9.9 ng/ml), while 18.5% (17/92) had mild vitamin D deficiency (10–14.9 ng/ml). When a serum 25(OH)D level of 20 ng/ml was used as a cutoff, 78.3% subjects were diagnosed to be vitamin D deficient/insufficient. The serum 1,25(OH)₂D level was within the normal range (40.6±20.1 pg/ml; mean ± SD). Mean (±SD) serum intact PTH, estimated in a limited number of subjects (n=15), was 72.3 (±21.0) pg/ml (range 36–100 pg/ml). There was a significant correlation between daily sun exposure and 25(OH)D levels (r=0.731, P<0.001). The serum 25(OH)D level correlated with BMD at the femoral neck and Ward's triangle (r=0.50, P=0.020 and r=0.46, P=0.037, respectively). Our findings show that vitamin D deficiency is common in urban north Indian hospital staff. The possible reasons include inadequate sunlight exposure and skin pigmentation in Indians. The serum 1,25(OH)₂D level is not a good indicator of vitamin D deficiency. A low serum 25(OH)D level is possibly one of the reasons for lower bone mineral density among Indians.     

Correction of preoperative vitamin D deficiency after Roux-en-Y gastric bypass surgery

BackgroundTo evaluate the adequacy of supplementation to correct preoperative vitamin D deficiency in adult patients during the year after Roux-en-Y gastric bypass (RYGB) surgery.MethodsThe medical records were reviewed and the preoperative and 12-month postoperative serum 25-hydroxyvitamin D [25(OH)D] levels were compared in patients who underwent RYGB from 2002 to 2004. The serum 25(OH)D levels were defined as being optimal (≥80 nmol/L), suboptimal (50–79 nmol/L), or deficient (<50 nmol/L). Patients with deficient 25(OH)D levels were prescribed 50,000 IU ergocalciferol weekly. The remaining patients averaged 710 IU supplemental vitamin D intake daily.ResultsThe mean patient age was 43.8 ± 10.7 years, and the mean preoperative body mass index was 51.8 ± 9.8 kg/m². Of the 95 patients with baseline and 12-month 25(OH)D levels, 89% were women. The mean preoperative 25(OH)D level was 49.7 ± 26.5 nmol/L; 34% had suboptimal 25(OH)D levels and 54% had deficient levels before surgery. Twelve months after surgery, those receiving 50,000 IU weekly (n = 40) had a mean 25(OH)D level of 69.2 ± 22.2 nmol/L; 63% had suboptimal and 8% deficient levels. Those taking 710 IU daily (n = 55) had a mean 25(OH)D level of 85.5 ± 33.0 nmol/L; 44% had suboptimal and 6% deficient levels.ConclusionVitamin D deficiency is prevalent in RYGB patients before surgery. The vitamin D status improved markedly after RYGB surgery with either 710 IU vitamin D daily or 50,000 IU weekly. Current supplementation practices do not appear to optimize the serum 25(OH)D levels and need to be more closely examined.     

Correction of preoperative vitamin D deficiency after Roux-en-Y gastric bypass surgery

BACKGROUND: To evaluate the adequacy of supplementation to correct preoperative vitamin D deficiency in adult patients during the year after Roux-en-Y gastric bypass (RYGB) surgery. METHODS: The medical records were reviewed and the preoperative and 12-month postoperative serum 25-hydroxyvitamin D [25(OH)D] levels were compared in patients who underwent RYGB from 2002 to 2004. The serum 25(OH)D levels were defined as being optimal (> or = 80 nmol/L), suboptimal (50-79 nmol/L), or deficient (<50 nmol/L). Patients with deficient 25(OH)D levels were prescribed 50,000 IU ergocalciferol weekly. The remaining patients averaged 710 IU supplemental vitamin D intake daily. RESULTS: The mean patient age was 43.8 +/- 10.7 years, and the mean preoperative body mass index was 51.8 +/- 9.8 kg/m2. Of the 95 patients with baseline and 12-month 25(OH)D levels, 89% were women. The mean preoperative 25(OH)D level was 49.7 +/- 26.5 nmol/L; 34% had suboptimal 25(OH)D levels and 54% had deficient levels before surgery. Twelve months after surgery, those receiving 50,000 IU weekly (n = 40) had a mean 25(OH)D level of 69.2 +/- 22.2 nmol/L; 63% had suboptimal and 8% deficient levels. Those taking 710 IU daily (n = 55) had a mean 25(OH)D level of 85.5 +/- 33.0 nmol/L; 44% had suboptimal and 6% deficient levels. CONCLUSION: Vitamin D deficiency is prevalent in RYGB patients before surgery. The vitamin D status improved markedly after RYGB surgery with either 710 IU vitamin D daily or 50,000 IU weekly. Current supplementation practices do not appear to optimize the serum 25(OH)D levels and need to be more closely examined.     

25‐OH‐Vitamin D Deficiency and Cellular Alloimmunity as Measured by Panel of Reactive T Cell Testing in Dialysis Patients

Primed antidonor alloreactive T cells are detrimental to transplant outcome, but factors that impact the strength of this immune response prior to transplantation are unknown. We tested peripheral blood mononuclear cells from dialysis patients, against panels of allogeneic, primary B‐cell lines in a newly standardized IFNγ ELISPOT panel of reactive T cell (PRT) assay. Results were correlated with known alloantibody‐sensitizing events and other clinical parameters. As 25‐OH‐vitamin D deficiency is associated with enhanced cellular immunity, is common in dialysis patients and is correctable, we assessed the relationship between serum 25‐OH‐vitamin D and the PRT. Using independent test and validation cohorts we found that low serum levels of 25‐OH‐vitamin D (<26 ng/mL) correlated with high‐PRT values (in the upper 50th percentile, OR 0.02, p = 0.01) independent of age, sex, race, previous transplant, transfusion, pregnancy, time on dialysis, panel of reactive antibody, iPTH, and treatment with 1,25‐OH‐vitamin D. The data provide a potential mechanism for the possible relationship between vitamin D deficiency and poor posttransplant outcome, and support studies to test the impact of 25‐OH‐vitamin D repletion on alloimmunity and allograft injury in kidney transplant candidates.     

Vitamin D deficiency in adult fracture patients: prevalence and risk factors

Purpose

Although vitamin D levels are not routinely monitored in outpatient fracture patients, identification of fracture patients with a deficient vitamin D status may be clinically relevant because of the potential role of vitamin D in fracture healing. This study aimed to determine the prevalence of and risk factors for vitamin D deficiency in non-operatively treated adult fracture patients.

Patients and methods

Vitamin D levels were determined in a cross-sectional study of adult patients, who were treated non-operatively for a fracture of the upper or lower extremity in the outpatient clinic of a level 1 trauma center, during one calendar year. Potential risk factors for (severe) vitamin D deficiency were analyzed using multivariable logistic regression analysis.

Results

A total of 208 men and 319 women with a mean age of 49.7 years (SD 19.9) were included. In this population, 71 % had a serum calcidiol <75 nmol/L, 40 % were vitamin D deficient (serum calcidiol <50 nmol/L) and 11 % were severely vitamin D deficient (serum calcidiol <25 nmol/L). Smoking and season (winter and spring) were independent risk factors for vitamin D deficiency. An increasing age, a non-Caucasian skin type, winter and smoking were identified as independent risk factors for severe vitamin D deficiency. The use of vitamin D, alcohol consumption and higher average daily sun exposure were independent protective factors against (severe) vitamin D deficiency.

Conclusion

Given the potential role of vitamin D in fracture healing, clinicians treating adult fracture patients should be aware of the frequent presence of vitamin D deficiency during the winter, especially in smoking and non-Caucasian patients. Research on the effect of vitamin D deficiency or supplementation on fracture healing is needed, before suggesting routine monitoring or supplementation.

     

Prevalence of vitamin D insufficiency in postmenopausal south Indian women

Aim: To evaluate the dietary calcium and vitamin D status in south Indian postmenopausal women. Methods: Postmenopausal women (n=164) were evaluated for their daily dietary calcium intake, phytate to calcium ratio, and bone mineral parameters. Their serum leutinizing hormone (LH), follicle-stimulating hormone (FSH), 25-hydroxyvitamin D (25[OH]D), and parathyroid hormone levels (PTH) were measured. Results: Their age and BMI were 59.5 ± 8 years and 27 ± 5 kg/m², respectively. Their daily dietary intake of calcium was 323 ± 66 mg/day; phytate to calcium ratio, 0.56±0.1; LH, 26 ± 13.5 µIU/l; and FSH, 62.6 ± 30 µIU/l. Their dietary intake of calcium was low compared with the recommended daily/dietary allowance (RDA) of the Indian Council of Medical Research (ICMR) for the Indian population. Of the 164 patients studied, based on population-based reference values, 126 (77%) had normal 25(OH)D levels (9–37.6 ng/ml), and 38 (23%) had 25(OH)D deficiency. Using functional health-based reference values, 30 (18%) patients had normal 25(OH)D levels (>20 ng/ml), 85 (52%) had 25(OH)D insufficiency (10–20 ng/ml), and 49(30%) had 25(OH)D deficiency (<10 ng/ml). PTH and serum alkaline phosphatase (SAP) was significantly high in patients with 25(OH)D deficiency (p<0.05) compared with those with normal 25(OH)D levels. There was a negative correlation between 25(OH)D and PTH (r=–0.2; p<0.007) and SAP (r=–0.2; p<0.001). Dietary calcium correlated positively with dietary phosphates (r=0.8; p<0.001) and phytate to calcium ratio (r=0.75; p<0.001). Conclusions: Population-based reference values underdiagnosed vitamin D insufficiency and overdiagnosed normal vitamin D status. The diet was insufficient in calcium and high in phytate. About 82% of the study group had varying degrees of low 25-hydroxyvitamin D levels. The quality of diet has to be improved with enrichment/supplementation of calcium and vitamin D to suppress secondary hyperparathyroidism-induced bone loss and risk of fractures.     

Vitamin D Deficiency in the Morbidly Obese

Although vitamin D deficiency has been well-documented following gastric bypass surgery, there are few studies of vitamin D status in the non-operative morbidly obese patient. We examined 25-hydroxyvitamin D (25-OHD) levels in 60 morbidly obese pre-operative females; 62% of them had 25-OHD levels below normal range (16-74 ng/ml) which were not associated with reductions in serum calcium or phosphorus, liver or kidney dysfunction, and were not significantly correlated to patients' age. However, 25-OHD levels were significantly (p < 0.0001) and negatively correlated to body mass (r = -0.49). These data suggest that low vitamin D may be associated with obesity per se. Hypovitaminosis D, when it is found in post-bariatric surgery patients, may not be caused by the surgery since it may have been present to some degree pre-operatively.     

Effect of Gastric Bypass on Vitamin D and Secondary Hyperparathyroidism

Obesity as well as bariatric surgery may increase the risk for vitamin D deficiency. We retrospectively compared vitamin D levels in obese patients (n = 123) prior to bariatric surgery and 1 year postoperatively. We also evaluated parathyroid hormone levels (PTH) 1 year after surgery. A higher percentage of patients had baseline vitamin D deficiency (86%), defined as 25-hydroxy vitamin D <32 ng/mL, compared with the 1-year (post-surgical) levels, (70%; p < 0.001). Body mass index (BMI) inversely correlated with vitamin D deficiency at baseline (r = −0.3, p = 0.06) and at the postoperative follow-up (r = −0.2, p = 0.013). One third of the postoperative population had secondary hyperparathyroidism, defined by a serum PTH level >62 pg/mL; however, postoperative PTH and vitamin D levels were unrelated (r = −0.001, p = 0.994). Pre- and postoperative vitamin D levels were inversely correlated with BMI. Secondary hyperparathyroidism was observed in 33% of patients postoperatively; however, this did not correlate with vitamin D.     

The long-term effects of gastric bypass on vitamin D metabolism

OBJECTIVE: Alterations of the endocrine system in patients following Roux-en-Y gastric bypass (GBP) are poorly described and have prompted us to perform a longitudinal study of the effects of GBP on serum calcium, 25-hydroxy-vitamin-D (vitamin D), and parathyroid hormone (PTH). METHODS: Prospectively collected data were compiled to determine how GBP affects serum calcium, vitamin D, and PTH. Student t test, Fisher exact test, or linear regression was used to determine significance. RESULTS: Calcium, vitamin D, and PTH levels were drawn on 243 patients following GBP. Forty-one patients had long-limb bypass (LL-GBP), Roux >100 cm, and 202 had short-limb bypass (SL-GBP), Roux < or =100 cm. The mean (+/-SD) postoperative follow-up time was significantly longer in the LL-GBP group (5.7 +/- 2.5 years) than the SL-GBP group (3.1 +/- 3.6 years, P < 0.0001). When corrected for albumin levels, mean calcium was 9.3 mg/dL (range, 8.5-10.8 mg/dL), and no difference existed between LL-GBP and SL-GBP patients. For patients with low vitamin D levels (<8.9 ng/mL), 88.9% had elevated PTH (>65 pg/mL) and 58.0% of patients with normal vitamin D levels (> or =8.9 ng/mL) had elevated PTH (P < 0.0001). In individuals with vitamin D levels <30 ng/mL, 55.1% (n = 103) had elevated PTH, and of those with vitamin D levels > or =30 ng/mL 28.5% (n = 16) had elevated PTH (P = 0.0007). Mean vitamin D levels were lower in patients who had undergone LL-GBP as opposed to those with SL-GBP, 16.8 +/- 10.8 ng/mL versus 22.7 +/- 11.1 ng/mL (P = 0.0022), and PTH was significantly higher in patients who had a LL-GBP (113.5 +/- 88.0 pg/mL versus 74.5 +/- 52.7 pg/mL, P = 0.0002). There was a linear decrease in vitamin D (P = 0.005) coupled with a linear increase in PTH (P < 0.0001) the longer patients were followed after GBP. Alkaline phosphatase levels were elevated in 40.3% of patients and correlated with PTH levels. CONCLUSION: Vitamin D deficiency and elevated PTH are common following GBP and progress over time. There is a significant incidence of secondary hyperparathyroidism in short-limb GBP patients, even those with vitamin D levels > or =30 ng/mL, suggesting selective Ca malabsorption. Thus, calcium malabsorption is inherent to gastric bypass. Careful calcium and vitamin D supplementation and long-term screening are necessary to prevent deficiencies and the sequelae of secondary hyperparathyroidism.