Calciumhomeostasis and Vitamin D in Obesity and Preeclampsia

Normal physiological functioning is highly dependent of calcium and the concentration range is very narrow. Normal calcium levels are so crucial to survival that the body will de-mineralize bone if the levels are insufficient. A prerequisite for normal calcium uptake is a normal Vitamin D level. Insufficient levels of Vitamin D are associated to several diseases. The aims of this thesis were to study the relationship between pregnancies and hyperparathyroidism (pHPT) (I), between pHPT and pregnancy with preeclampsia (II) and also to determine if disturbances in calcium homeostasis with vitamin D deficiency are apparent in preeclamptic women (III).  The aim was also to study calciumhomeostasis in obese patients before and after bariatric surgery (IV and V) with emphasis on vitamin D status, parathyroid secretion and bone mineral density (BMD). A correlation was found between a history of pHPT and pregnancy with preeclampsia, with an odds ratio of 6,89 ( 95% CI 2.30, 20.58).  Parathyroid hormone was significantly raised in preeclamptic pregnancies but vitamin D deficiency was present both in preeclamptic and healthy pregnancies. A certain polymorphism of the Vitamin D receptor (baT haplotype), overrepresented in pHPT, was not over expressed in preeclampsia. Hypovitaminosis D was present in more than 70% of bariatric patients preoperatively, which did not change after surgery, despite great weight loss and start of Vitamin D supplementation. BMD was significantly lower in bariatric patients with a negative correlation to the time elapsed since surgery. A small increase in BMD could be noted 10-13 years after bariatric surgery, possibly due to gradual weight gain. CiCa-clamping in obese patients demonstrated a disturbed calcium homeostasis with a left-shifted calcium-PTH relationship and a lower set-point of calcium. This disturbance persisted one year postoperatively. In conclusion, derangements in calcium homeostasis with decreased levels of Vitamin D are present in preeclampsia and obesity. A history of pHPT should be viewed as a risk factor for preeclampsia. Life long follow-up is necessary after bariatric surgery, and an individually adjusted high dose Vitamin D substitute is probably needed to avoid a development of osteoporosis

Cholecalciferol Injections Are Effective in Hypovitaminosis D After Duodenal Switch : a Randomized Controlled Study

Background: By treating obesity, one of the major epidemics of this past century, through bariatric surgery, we may cause complications due to malnourishment in a growing population. At present, vitamin D deficiency is of interest, especially in patients with inferior absorption of fat-soluble nutrients after biliopancreatic diversion with duodenal switch (BPD/DS). Methods: Twenty BPD/DS patients, approximately 4 years postoperatively, were randomized to either intramuscular supplementation of vitamin D with a single dose of 600,000 IU cholecalciferol, or a control group. Patients were instructed to limit their supplementation to 1400 IU of vitamin D and to avoid the influence of UV-B radiation; the study was conducted when sunlight is limited (December to May). Results: Despite oral supplementation, a pronounced deficiency in vitamin D was seen (injection 19.3; control 23.2 nmol/l) in both groups. The cholecalciferol injection resulted in elevated 25[OH]D levels at 1 month (65.4 nmol/l), which was maintained at 6 months (67.4 nmol/l). This resulted in normalization of intact parathyroid hormone (PTH) levels. No changes in vitamin D or PTH occurred in the control group. Conclusions: In BPD/DS patients, having hypovitaminosis D despite full oral supplementation, a single injection of 600,000 IU of cholecalciferol was effective in elevating vitamin D levels and normalizing levels of intact PTH. The treatment is simple and highly effective and thus recommended, especially in cases of reduced UV-B radiation

Association of postoperative infection and oncological outcome after breast cancer surgery

Background: Surgical-site infection (SSI) is a well known complication after breast cancer surgery and has been reported to be associated with cancer recurrence. The aim of this study was to investigate the association between SSI and breast cancer recurrence, adjusting for several known confounders. The secondary aim was to assess a possible association between any postoperative infection and breast cancer recurrence. Method: This retrospective cohort study included all patients who underwent breast cancer surgery from January 2009 to December 2010 in the Uppsala region of Sweden. Data collected included patient, treatment and tumour characteristics, infection rates and outcome. Association between postoperative infection and oncological outcome was examined using Kaplan-Meier curves and Cox regression analysis. Results: Some 492 patients (439 with invasive breast cancer) with a median follow-up of 8.4 years were included. Mean(s.d.) age was 62(13) years. Sixty-two (14.1 per cent) of those with invasive breast cancer had an SSI and 43 (9.8 per cent) had another postoperative infection. Some 26 patients had local recurrence; 55 had systemic recurrence. Systemic recurrence was significantly increased after SSI with simple analysis (log rank test, P = 0.035) but this was not observed on adjusted analysis. However, tumour size and lymph node status remained significant predictors for breast cancer recurrence on multiple regression. Other postoperative infections were not associated with recurrence. Conclusion: Neither SSI nor other postoperative infections were associated with worse oncological outcome in this study. Rather, other factors that relate to both SSI and recurrence may be responsible for the association seen in previous studies

Low bone mineral density following gastric bypass is not explained by lifestyle and lack of exercise

Background Bariatric surgery, Roux-en-Y gastric bypass (RYGBP) in particular, is associated with weight loss as well as low bone mineral density. Bone mineral density relies upon multiple factors, some of which are lifestyle factors. The aim of this study was to compare lifestyle factors in order to eliminate them as culprits of the suspected difference in BMD in RYGBP operated and controls. Materials and methods Study participants included 71 RYGBP-operated women (42.3 years, BMI 33.1 kg/m2) and 94 controls (32.4 years, BMI 23.9 kg/m2). Each completed a DEXA scan, as well as survey of lifestyle factors (e.g. physical activity in daily life, corticosteroid use, and calcium intake). All study participants were premenopausal Caucasian women living in the same area. Blood samples were taken in RYGBP-patients. Results BMD was significantly lower in RYGBP, femoral neck 0.98 vs. 1.04 g/cm2 compared to controls, despite higher BMI (present and at 20 years of age) and similar physical activity and calcium intake. In a multivariate analysis, increased time since surgery and age were negatively associated with BMD of the femoral neck and total hip in RYGBP patients. Conclusion Despite similar lifestyle, RYGBP was followed by a lower BMD compared to controls. Thus, the reduced BMD in RYGBP cannot be explained, seemingly nor prevented, by lifestyle factors. As the reduction in BMD was associated with time since surgery, strict follow-up is a lifelong necessity after bariatric surgery, and especially important in younger bariatric patients

Prospective Evaluation of Complications and Associated Risk Factors in Breast Cancer Surgery

Background; Surgical site infection (SSI) is a well-known complication after breast cancer surgery. The primary aim was to assess risk factors for SSI. Risk factors for other wound complications were also studied. Materials and Methods: In this prospectively registered cohort study, patients who underwent breast-conserving surgery (BCS) or mastectomy between May 2017 and May 2019 were included. Data included patient and treatment characteristics, infection, and wound complication rates. Risk factors for SSI and wound complications were analyzed with simple and multiple logistic regression. Results: The study cohort consisted of 592 patients who underwent 707 procedures. There were 66 (9.3%) SSI and 95 (13.4%) wound complications. "BMI > 25, " "oncoplastic BCS, " "reoperation within 24 hour, " and "prolonged operative time " were risk factors for SSI with simple analysis. BMI 25-30 and > 30 remained as significant risk factors for SSI with adjusted analysis. Risk factors for "any wound complication " with adjusted analysis were "mastectomy with/without reconstruction " in addition to "BMI 25-30 " and "BMI > 30. " Conclusion: The only significant risk factor for SSI on multivariable analysis were BMI 25-30 and BMI > 30. Significant risk factors for "any wound complication " on multivariable analysis were "mastectomy with/without reconstruction " as well as "BMI 25-30 " and "BMI > 30.

Hypoparathyroidism after total thyroidectomy in patients with previous gastric bypass

Purpose Case reports suggest that patients with previous gastric bypass have an increased risk of severe hypocalcemia after total thyroidectomy, but there are no population-based studies. The prevalence of gastric bypass before thyroidectomy and the risk of hypocalcemia after thyroidectomy in patients with previous gastric bypass were investigated. Methods By cross-linking The Scandinavian Quality Registry for Thyroid, Parathyroid and Adrenal Surgery with the Scandinavian Obesity Surgery Registry patients operated with total thyroidectomy without concurrent or previous surgery for hyperparathyroidism were identified and grouped according to previous gastric bypass. The risk of treatment with intravenous calcium during hospital stay, and with oral calcium and vitamin D at 6 weeks and 6 months postoperatively was calculated by using multiple logistic regression in the overall cohort and in a 1:1 nested case-control analysis. Results We identified 6115 patients treated with total thyroidectomy. Out of these, 25 (0.4 %) had undergone previous gastric bypass surgery. In logistic regression, previous gastric bypass was not associated with treatment with i.v. calcium (OR 2.05, 95 % CI 0.48-8.74), or calcium and/or vitamin D at 6 weeks (1.14 (0.39-3.35), 1.31 (0.39-4.42)) or 6 months after total thyroidectomy (1.71 (0.40-7.32), 2.28 (0.53-9.75)). In the nested case-control analysis, rates of treatment for hypocalcemia were similar in patients with and without previous gastric bypass. Conclusion Previous gastric bypass surgery was infrequent in patients undergoing total thyroidectomy and was not associated with an increased risk of postoperative hypocalcemia