Hyperparathyroidism and new onset diabetes after renal transplantation.

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

Persistent hyperparathyroidism in renal transplant patients

Abstract Disorders in mineral metabolism and secondary hyperparathyroidism (sHPT) are well known complications in patients with chronic kidney disease (CKD). Hyperparathyroidism (HPT) persists in a majority of patients after kidney transplantation (KTx). Parathyroidec-tomy (PTX) is indicated in patients who are resistant to medical therapy both before and after KTx. Overall aims of this thesis were to investigate, I, incidence of PTX in patients with therapy resistant sHPT on renal replacement therapy; II, to study the effects of persistent HPT on bone mineral density (BMD) in long-term kidney transplant patients, and III, whether DXA can predict fractures in this patient group. A further aim was, IV, to investigate the role of HPT as a risk factor for new onset diabetes after KTx (NODAT). Results: PTX rate was 8.8 per 1000 person years. This rate varied markedly over time. PTH had a negative impact on cortical bone. Osteoporosis, osteopenia and BMD < 0.9 g/cm2 in the hip region were all independent risk factors for fracture. An elevated PTH level was strongly associated with new onset diabetes after KTx. Conclusion: We believe that the observed variation in PTX rate is due to the results of previous research showing the detrimental effects of mineral disorders and severe sHPT in CKD patients; and to the introduction of novel medications such as cinacalcet. We found that PTH had a negative impact on BMD in KTx patients and that DXA is a useful tool to predict fracture in these patients. In addition, we showed that PTH was strongly associated with NODAT

Can DXA Predict Fractures in Renal Transplant Patients?

Renal transplant patients have a high prevalence of osteopenia, osteoporosis and fractures. The aim of the study was to investigate whether dual-energy x-ray absorptiometry (DXA) is of value to predict fractures. In 1995-2007, 238 renal transplant patients underwent 670 DXA investigations. Osteopenia (46.0%), osteoporosis (13.9%) and absolute bone mineral density (BMD) (median 0.9, range 0.4-2.0 g/cm(2)) in the hip region were used to evaluate fracture risk. Data on fractures were collected at the occasion of each DXA, and a questionnaire was filled in by 191 patients at regular outpatient visits. Reported fractures were verified by consultation of medical records. In all, 46 patients had 53 fractures. Cumulative hazard of fracture was significantly different among normal BMD, osteopenia and osteoporosis in the hip (p < 0.0001). A Cox proportional hazard analysis also including age, gender and diabetic nephropathy showed significantly increased fracture risk for osteoporosis (3.5 times, CI 1.8-6.4, p = 0.0001) as well as for osteopenia (2.7 times, 1.6-4.6, p = 0.0003). A significantly increased risk was also found with absolute BMD estimates below the median. Osteopenia and an absolute bone density below 0.9 g/cm(2) in the hip region confer an increased risk of fracture

Cardiovascular and Cerebrovascular Events After Parathyroidectomy in Patients on Renal Replacement Therapy

Background: A majority of patients with end-stage renal disease suffer from secondary hyperparathyroidism, which is associated with osteoporosis and cardiovascular disease. Parathyroidectomy (PTX) is often necessary despite medical treatment. However, the effect of PTX on cardio- and cerebrovascular events (CVE) remains unclear. Data on the effect of PTX from population-based studies are scarce. Some studies have shown decreased incidence of CVE after PTX. The aim of this study was to evaluate the effect of PTX on risk of CVE in patients on renal replacement therapy. Methods: We performed a nested case–control study within the Swedish Renal Registry (SRR) by matching PTX patients on dialysis or with functioning renal allograft with up to five non-PTX controls for age, sex and underlying renal disease. To calculate time to CVE, i.e., myocardial infarct, stroke and transient ischemic attack, control patients were assigned the calendar date (d) of the PTX of the case patient. Crude and adjusted proportional hazards regressions with random effect (frailty) were used to calculate hazard ratios for CVE. Results: The study cohort included 20,056 patients in the SRR between 1991 and 2009. Among these, 579 patients had undergone PTX, 423 during dialysis and 156 during time with functioning renal allograft. These patients were matched with 1234 dialysis and 736 transplanted non-PTX patients. The adjusted hazard ratio (HR) with 95% confidence interval (CI) of CVE after PTX was 1.24 (1.03–1.49) for dialysis patients compared with non-PTX patients. Corresponding results for patients with renal allograft at d were HR (95% CI) 0.53 (0.34–0.84). Conclusions: PTX patients on dialysis at d had a higher risk of CVE than patients without PTX. Patients with renal allograft at d on the other had a lower risk after PTX than patients without PTX

The effect of parathyroidectomy on patient survival in secondary hyperparathyroidism.

Secondary hyperparathyroidism is a common condition in patients with end-stage renal disease and is associated with osteoporosis and cardiovascular disease. Despite improved medical treatment, parathyroidectomy (PTX) is still necessary for many patients on renal replacement therapy. The aim of this study was to evaluate the effect of PTX on patient survival

Total versus subtotal parathyroidectomy for secondary hyperparathyroidism

Background: It remains unclear whether total or subtotal parathyroidectomy for secondary hyperparathyroidism yields the best outcomes. We investigated mortality, cardiovascular events, hip fracture, and recurrent parathyroidectomy after total versus subtotal parathyroidectomy in patients on renal replacement therapy. Methods: Using the Swedish Renal Registry, the surgical registry for thyroid and parathyroid surgery, and the National Inpatient Registry, we identified patients who underwent parathyroidectomy between 1991 and 2013. We calculated the risk of outcome after total versus subtotal parathyroidectomy using COX's regression, adjusting for age, sex, cause of renal disease, time with a functioning graft before and after parathyroidectomy, Charlson comorbidity index, year of surgery, prevalent cardiovascular disease, time on dialysis, renal transplantation at parathyroidectomy, and treatment with calcimimetics before parathyroidectomy. Results: There were 824 patients who underwent parathyroidectomy, 388 total and 436 subtotal. There was no difference in mortality or risk of incident hip fracture between groups. Comparing the subtotal with the total parathyroidectomy, the adjusted hazard ratio (95% confidence interval) for cardiovascular events was 0.43 (0.25–0.72) and for recurrent parathyroidectomy 3.33 (1.33–8.32). Conclusion: There was a higher risk of cardiovascular events in patients after total parathyroidectomy compared with subtotal parathyroidectomy, but a lower risk of recurrent parathyroidectomy

The Effect of Parathyroidectomy on Risk of Hip Fracture in Secondary Hyperparathyroidism

Background: Secondary hyperparathyroidism increases the risk for fractures. Despite improvement in medical therapy, surgical parathyroidectomy (PTX) often becomes necessary, but its effect on risk of fractures is not clear. Our aim was to study the effect of parathyroidectomy on the risk of hip fractures in patients on dialysis or with a functioning renal graft at time of parathyroidectomy.Design: In a cohort of 20,056 patients on dialysis or with functioning renal allograft, we identified 590 patients who underwent parathyroidectomy between 1991 and 2009. Of these, 579 were matched with 1970 non-PTX patients on age, sex, cause of renal disease and functioning renal allograft or not at the time of PTX or at the corresponding time for non-PTX patients (t). We calculated the risk for hip fracture after PTX using crude and adjusted Cox proportional hazards regressions, adjusting for time in renal replacement therapy before t, time with functioning renal allograft before and after t, comorbidity at t and a hip fracture before t. Results: The adjusted hazard ratio (95% confidence interval) for hip fracture was 0.40 (0.18–0.88) for PTX patients, compared to non-PTX patients. When analyses were performed separately for sex, only women had a lower risk of hip fracture after PTX compared to non-PTX patients. The risk of hip fracture after PTX was similar in patients with or without functioning renal allograft at time for PTX. Conclusion: Parathyroidectomy is associated with a lower risk of hip fracture in female patients with secondary hyperparathyroidism

Temporal trends and risk factors for parathyroidectomy in the Swedish dialysis and transplant population - a nationwide, population-based study 1991 - 2009.

Many patients on renal replacement therapy (RRT) require parathyroidectomy (PTX). Trends and current rates of PTX on a national level are not known. Furthermore, it is not completely clear which factors influence rates of PTX. Thus, our aim was to investigate the incidence, regional distribution and factors associated with PTX as well as possible temporal changes, in the Swedish RRT population