Renal dysfunction in primary hyperparathyroidism; effect of Parathyroidectomy: A retrospective Cohort Study

Risk of neuropsychiatric disorders in primary hyperparathyroidism: Parathyroidectomy versus nonoperative management

BACKGROUND

Neuropsychiatric disorders frequently manifest in primary hyperparathyroidism (PHPT), yet evidence of parathyroidectomy's benefit remains mixed. We sought to compare the incidence of neuropsychiatric disorders among patients treated with parathyroidectomy versus nonoperative management.

METHODS

We retrospectively reviewed our institutional administrative database for patients with PHPT. Patients with secondary hyperparathyroidism were excluded. The date of biochemical diagnosis of PHPT was designated as day 0 and new-onset neuropsychiatric disorders were defined as conditions diagnosed after this date. The risk of new-onset neuropsychiatric disorders in propensity score-matched surgical and nonsurgical patients was compared using the Cox regression over a median follow-up of 4.2 years.

RESULTS

Our cohort included 3728 patients, predominantly female (78%) and white (63.9%), with a mean (± Standard deviation) age of 62 ± 14 years. Of these, 1704 (45.7%) underwent parathyroidectomy. After propensity score matching and adjusting for clinical characteristics, patients who had parathyroidectomy showed a reduced hazard ratio (HR) for new-onset cognitive impairment (HR: 0.65, 95% CI: 0.47-0.91), somnolence (HR: 0.45, 95% CI: 0.23-0.9) and schizophrenia (HR: 0.08, 95% CI: 0.01-0.6), but not for anxiety (HR: 1.07, 95% CI: 0.83-1.37), depression (HR: 1.02, 95% CI: 0.77-1.36) or suicidal ideation (HR: 0.31, 95% CI: 0.04-2.71). Additionally, surgical patients were less likely to require inpatient care (0.3% vs. 1.8%, p < 0.001) for neuropsychiatric disorders.

CONCLUSIONS

Parathyroidectomy is associated with lower risks of new-onset cognitive impairment, schizophrenia, or somnolence, indicating potential benefit of operative management in improving neuropsychiatric symptoms in patients with PHPT.

Renal complications in chronic hypoparathyroidism - a systematic cross-sectional assessment

Context

Although renal long-term complications are acknowledged in chronic hypoparathyroidism (HPT), standardized investigations are scarce.

Objective

To systematically investigate renal complications and their predictors in hypoparathyroid patients compared to matched individuals.

Design

Prospective observational study in 161 patients with chronic HPT.

Methods

Patients received renal ultrasound, clinical and laboratory assessments. An individual 1:3 matching with participants from the German population-based Study of Health in Pomerania was performed.

Results

Of 161 patients (92% postoperative HPT), prevalence of eGFR <60ml/min/1.73m2 was 21%, hypercalciuria 41%. Compared to healthy individuals, HPT patients had a significantly lower eGFR (74.2 vs. 95.7 ml/min/1.73m², p<0.01). Renal ultrasound revealed calcifications in 10% (nephrocalcinosis in 7% and calculi in 3%). Patients with renal calcifications had higher levels of 24-hour urine calcium excretion (8.34 vs. 5.08 mmol/d, p=0.02), spot urine calcium excretion (4.57 vs. 2.01 mmol/L, p=0.01) and urine calcium-to-creatinine ratio (0.25 vs. 0.16, p<0.01) than patients without calcifications. Albumin-corrected calcium, phosphate, calcium-phosphate product, 25-hydroxyvitamin D in serum, eGFR, daily calcium intake or disease duration were not significantly different between these two groups. Including patients receiving rhPTH therapy, a lower serum phosphate concentration (odds ratio 1.364 [95% confidence interval (CI) 1.049-1.776], p<0.05) and a longer disease duration of HPT (odds ratio 1.063 [95% CI 1.021-1.106], p<0.01) were significant predictors for renal calcifications. Excluding patients receiving rhPTH therapy, a higher 24-hour urine calcium excretion (odds ratio 1.215 [95% CI 1.058-1.396], p<0.01) was a significant predictor for renal calcifications but not serum magnesium or disease duration.

Conclusions

Prevalence of impaired renal function among patients with chronic HPT is increased and independent from visible renal calcifications. Depending on exclusion of patients with rhPTH therapy, regression analysis revealed disease duration and serum phosphate or disease duration and 24-hour urinary calcium excretion as predictors for renal calcifications.

Clin Trials Identifier

NCT05585593.

Effects of parathyroidectomy on kidney function in patients with primary hyperparathyroidism: Results of a prospective study

BACKGROUND

Altered glomerular filtration rate is a controversial indication for parathyroidectomy in patients with primary hyperparathyroidism. The objective of this study was to evaluate the estimated glomerular filtration rate change 12 months after parathyroidectomy for primary hyperparathyroidism according to preoperative kidney function.

METHOD

Patients who underwent parathyroidectomy for primary hyperparathyroidism between 2016 and 2021 (n = 381) were enrolled in a monocentric prospective cohort. Patients without 1-year follow-up or with missing data were excluded (n = 135, 35%). Patients were dichotomized according to their baseline estimated glomerular filtration rate: <60 mL/min (group 1) and ≥60 mL/min (group 2). Parameters were measured before and then at 6 and 12 months after parathyroidectomy.

RESULTS

Out of 246 included patients, 27 (11%) were assigned to group 1 and 219 (89%) to group 2. The mean baseline estimated glomerular filtration rate was 46.8 ± 11.5 and 87.3 ± 14.7 mL/min in groups 1 and 2, respectively. Group 1 patients were older (P = .0006) and had a higher median serum parathyroid hormone level (P = .021). At 6 months postoperative, 224 patients (91%) were normocalcemic. The estimated glomerular filtration rate raw change after parathyroidectomy was significantly higher in group 1 than in group 2 (4.2 ± 7.8 vs -2.2 ± 9.1 mL/min, P = .0004). In group 1, 13/27 patients (48%) improved their chronic kidney disease stage after parathyroidectomy, including 6/13 (46%) with postoperative estimated glomerular filtration rate ≥60 mL/min, whereas 2/27 (7%) worsened. The baseline estimated glomerular filtration rate <60 mL/min and elevated serum calcium level were associated with postoperative estimated glomerular filtration rate improvement in multivariable analysis (P = .0023 and .039, respectively).

CONCLUSION

Parathyroidectomy for primary hyperparathyroidism is more likely to improve kidney function in patients with preoperative estimated glomerular filtration rate <60 mL/min. These results strengthen the current guidelines for surgery.

Classical and Nonclassical Manifestations of Primary Hyperparathyroidism

This narrative review summarizes data on classical and nonclassical manifestations of primary hyperparathyroidism (PHPT). It is based on a rigorous literature search, inclusive of a Medline search for systematic reviews from 1940 to December 2020, coupled with a targeted search for original publications, covering four databases, from January 2013-December 2020, and relevant articles from authors' libraries. We present the most recent information, identify knowledge gaps, and suggest a research agenda. The shift in the presentation of PHPT from a predominantly symptomatic to an asymptomatic disease, with its varied manifestations, has presented several challenges. Subclinical nephrolithiasis and vertebral fractures are common in patients with asymptomatic disease. The natural history of asymptomatic PHPT with no end organ damage at diagnosis is unclear. Some observational and cross-sectional studies continue to show associations between PHPT and cardiovascular and neuropsychological abnormalities, among the different disease phenotypes. Their causal relationship is uncertain. Limited new data are available on the natural history of skeletal, renal, cardiovascular, neuropsychological, and neuromuscular manifestations and quality of life. Normocalcemic PHPT (NPHPT) is often diagnosed without the fulfillment of rigorous criteria. Randomized clinical trials have not demonstrated a consistent long-term benefit of parathyroidectomy (PTX) versus observation on nonclassical manifestations. We propose further refining the definition of asymptomatic disease, into two phenotypes: one without and one with evidence of target organ involvement, upon the standard evaluation detailed in our recommendations. Each of these phenotypes can present with or without non-classical manifestations. We propose multiple albumin-adjusted serum calcium determinations (albumin-adjusted and ionized) and exclusion of all secondary causes of high parathyroid hormone (PTH) when establishing the diagnosis of NPHPT. Refining the definition of asymptomatic disease into the phenotypes proposed will afford insights into their natural history and response to interventions. This would also pave the way for the development of evidence-based guidance and recommendations. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

The effect of parathyroidectomy compared to non-surgical surveillance on kidney function in primary hyperparathyroidism: a nationwide historic cohort study

BACKGROUND

Patients with primary hyperparathyroidism (pHPT) and impaired kidney function (estimated glomerular filtration rate (eGFR) < 60 mL/min) are offered parathyroidectomy (PTX) to protect them from further complications. Surprisingly, two recent uncontrolled cohort studies have suggested a further decrease in kidney function following PTX. We aimed to examine the effects of PTX compared to non-surgical surveillance on kidney function in pHPT patients.

METHODS

Historic cohort study. From the Danish National Patient Registry (NPR) and major medical biochemistry laboratories in Denmark, we identified 3585 patients with biochemically confirmed pHPT among whom n = 1977 (55%) were treated with PTX (PTX-group) whereas n = 1608 (45%) were followed without surgery (non-PTX group). Baseline was defined as time of diagnosis and kidney function was re-assessed 9-15 months after PTX (PTX group) or 9-15 months after diagnosis (non-PTX group).

RESULTS

At follow-up, eGFR had decreased significantly in the PTX- compared to the non-PTX-group (median - 4% vs. - 1%, p < 0.01). Stratification by baseline eGFR showed that the decrease was significant for those with a baseline eGFR value of 80-89 and > 90 mL/min, but not for those with lower eGFR values. Findings did not differ between patients with mild compared to moderate/severe hypercalcemia. However, after mutual adjustments, we identified baseline levels of calcium, PTH, and eGFR as well as age and treatment (PTX vs. no-PTX) as independent predictors for changes in kidney function.

CONCLUSION

Compared to non-surgical surveillance, PTX is associated with a small but significant decrease in kidney function in pHPT patients with an initial normal kidney function.

Baseline renal dysfunction determines mortality following parathyroidectomy in primary hyperparathyroidism: analysis of Indian PHPT registry

INTRODUCTION

Primary hyperparathyroidism (PHPT) in India is mostly symptomatic with renal and skeletal complications. Evidence on mortality outcomes following parathyroidectomy from India, where the disease is predominantly symptomatic is limited.

MATERIAL AND METHODS

This was a prospective study to evaluate mortality outcomes in the Indian PHPT registry over the past 25 years (n = 464). Pre- and postoperative parameters and mortality data were obtained from medical records and/or by verbal autopsy, a method validated by WHO for data collection in settings where several deaths are noninstitutional. Patients were divided into survivor (SG) and nonsurvivor groups (NSG) to ascertain differences in presentation and the effect of parathyroidectomy.

RESULTS

The overall mortality was 8.8% at a median follow-up of 8 years (IQR 1-13) after parathyroidectomy. Chronic kidney disease was the most common background cause of death (43.5%), followed by pancreatitis (28.2%). NSG had significantly more frequent renal dysfunction (91.9% vs 73.9%), anaemia (50 vs 16.6%) and pancreatitis (24.3 vs 6.4%). PTH (61.9 vs 38.3 pmol/l) and baseline creatinine (97.2 vs 70.7 µmol/l) were significantly higher and eGFR lower (66.7 vs 90.7 ml/min/1.73m²) in the NSG than SG. By Cox proportional modelling, renal dysfunction [HR 2.88 (1.42-5.84)], anaemia [HR 2.45 (1.11-5.42)] and pancreatitis [HR 2.65 (1.24-5.66)] on univariate and renal dysfunction [HR 3.33 (1.13-9.77)] on multivariate analysis were significant for mortality. Survival curves demonstrated a significantly higher mortality with lower eGFR values.

CONCLUSIONS

Nonsurvivors in PHPT had greater prevalence and more severe baseline renal dysfunction than survivors. Survival after parathyroidectomy was significantly associated with estimated glomerular filtration rate at baseline.

Parathyroidectomy slows renal function decline in patients with primary hyperparathyroidism

PURPOSE

Primary hyperparathyroidism has deleterious effects on health and causes nephrolithiasis and osteoporosis. However, it remains unclear whether parathyroidectomy benefits kidney function among patients with primary hyperparathyroidism.

METHODS

In this retrospective study, patients with primary hyperparathyroidism receiving parathyroidectomy in a tertiary medical center between 2003 and 2017 were followed up until December 31 2017, death, or requiring renal replacement therapy. Impact of parathyroidectomy on kidney function was examined using longitudinal estimated glomerular filtration rate (eGFR) change scales: single, average, absolute difference, percent change, annual decline rate, and slope. We applied linear mixed-effect model to determine the effect of parathyroidectomy on kidney function.

RESULTS

During study period, 167 patients with primary hyperparathyroidism were identified from 498 parathyroidectomized patients, and finally, 27 patients fulfilled our stringent criteria. Median follow-up duration was 1.50 years (interquartile range 1.05-1.81) before surgery and 2.47 years (1.37-6.43) after surgery. Although parathyroidectomy did not affect amount of proteinuria and distribution of eGFR, parathyroidectomy significantly slowed decline rate of eGFR compared with that before surgery (- 1.67 versus - 2.73 mL/min/1.73 m²/year, p < 0.001). More importantly, parathyroidectomy made more beneficial effects on kidney function in patients with age < 65 years and those without chronic kidney disease or hypertension.

CONCLUSIONS

Our study showed that parathyroidectomy slows renal function decline irrespective of age or comorbidities, which offers novel insight into the revision of guidelines for surgical indications in primary hyperparathyroidism. Given small sample size, further large-scale controlled studies are warranted to confirm our findings.

A detailed appraisal of renal manifestations in primary hyperparathyroidism from Indian PHPT registry: Before and after curative parathyroidectomy

BACKGROUND

Primary hyperparathyroidism (PHPT) is a systemic disorder characterized by hypercalcaemia and inappropriately elevated parathyroid hormone (PTH). Renal manifestations are one of the main presenting features both in symptomatic and asymptomatic PHPT patients.

OBJECTIVES

We aimed to compare demographic, clinical and biochemical parameters of PHPT patients with and without renal manifestations and also analysed the influence of curative parathyroidectomy on renal functions.

METHODS

We retrospectively analysed the data of PHPT patients from the last 25 years (1995- March 2019) and compared the demographic and clinical presentation and biochemical measurements between patients with and without renal manifestations and evaluated the changes in renal functions after 1 year of curative parathyroidectomy.

RESULTS

Of the total 544 PHPT patients, 299 (55%) including 91 out of 141 (65%) males had renal manifestations. Among renal manifestations, nephrolithiasis and nephrocalcinosis were found in 41.7% and 27.6% PHPT patients, respectively. PHPT patients with renal manifestations had significantly higher creatinine (109.7 vs 79.6 µmol/L; P < .0001) and lower eGFR level (78.8 vs 93.9 mL/min/1.73 m² ; P < .0001) compared to patients without renal manifestations. Parathyroidectomy resolved the clinical symptoms with biochemical cure in the patients from both the groups. Patients with renal manifestations showed improvement in creatinine and eGFR levels after 1 year of curative parathyroidectomy; however, patients without renal manifestations showed no change in creatinine and eGFR levels.

CONCLUSION

Young age and male gender are predictors of renal manifestations in PHPT. Curative parathyroidectomy improves renal functions in PHPT patients with renal manifestations compared to PHPT patients without renal manifestation.

The effect of chronic kidney disease on intraoperative parathyroid hormone: A linear mixed model analysis

BACKGROUND

Reduced creatinine clearance is an indication for surgery in asymptomatic primary hyperparathyroidism, and a significant proportion of patients undergoing parathyroidectomy have chronic kidney disease. The purpose of this study was to evaluate the kinetics of intraoperative parathyroid hormone decline during parathyroidectomy in patients who have chronic kidney disease compared with those with who have normal renal function.

METHODS

This is a single-center, retrospective study of patients with primary hyperparathyroidism undergoing parathyroidectomy (n = 646). Patients were grouped based on estimated glomerular filtration rate greater than (normal renal function) or less than (chronic kidney disease) 60 mL/min/1.73m². All patients had intraoperative parathyroid hormone monitoring and ≥6-month postoperative serum studies to confirm surgical cure. Intraoperative parathyroid hormone kinetic curves were analyzed using a linear mixed model.

RESULTS

Despite similar pre-excision values, patients with chronic kidney disease had significantly higher intraoperative parathyroid hormone values at 5 minutes (76 vs 58 pg/mL, P = .02) and 10 minutes (54 vs 37 pg/mL, P = .004) postexcision. No significant difference was observed in whether patients met Miami criterion by 5 minutes (chronic kidney disease 71%, normal renal function 78%, P = .255) or by 10 minutes (chronic kidney disease 95%, normal renal function 96%, P = .751) postexcision. Using a linear mixed model, glomerular filtration rate did not have a significant effect on the change in intraoperative parathyroid hormone over time.

CONCLUSION

Patients with chronic kidney disease had significantly higher postexcision intraoperative parathyroid hormone levels. However, renal function did not affect the change in intraoperative parathyroid hormone over time, nor did renal function ultimately affect the likelihood of meeting the Miami criterion. Intraoperative parathyroid hormone monitoring remains useful in this population, although additional time points may be needed to observe normalization of values.

Bone Turnover Markers in Response to Ultrasound-Guided Microwave Ablation for Primary Hyperparathyroidism

OBJECTIVE

To assess the efficacy and safety of ultrasound-guided microwave ablation (MWA) in the treatment of primary hyperparathyroidism (PHPT), and to investigate whether MWA can improve the bone turnover and renal function.

METHODS

A total of 20 consecutive PHPT patients with 21 parathyroid lesions treated with MWA in our center from May 2019 to March 2021 were recruited in this study. Serum parathyroid hormone (PTH), calcium and phosphorus levels before MWA and at 20 minutes, 4 hours, 1 day, 3 months, 6 months and 12 months after MWA were measured. Bone turnover biomarkers, renal function and lesion volume with volume reduction rate (VRR) before MWA and at the last follow-up were compared. Any complication related with MWA was evaluated. The technical and clinical success rates of MWA in the treatment of PHPT were calculated. Clinical success was defined as normal serum PTH and calcium without PHPT-associated manifestations at more than 6 months after ablation. Technical success was defined as complete ablation indicated by immediate postoperative contrast-enhanced ultrasound.

RESULTS

The serum PTH, calcium and phosphorus levels at their respective follow-up time points dropped significantly after MWA (P <0.05). The volume of parathyroid lesions at the final examination was significantly reduced, compared with pre-ablation volume (P <0.001), with a median VRR reaching 89%. The technical and clinical success rates were 100% and 63.6%, respectively. Substantial changes of bone turnover biomarkers were observed before and after MWA (P <0.05), but the differences in renal function were not statistically significant. No major complications were reported in all cases. Pre-MWA serum PTH, lesion volume, maximum diameter of lesion and ablation time were significantly different between patients with successful and failed MWA.

CONCLUSIONS

PHPT can be effectively and safely treated by ultrasound-guided MWA, as proven by drop in serum PTH and reduction in the volume of parathyroid adenomas. Besides, MWA can impede bone remodeling to suppress hyperparathyroidism in the condition of PHPT.

Effects of preoperative calcium levels and parathyroidectomy on renal function in primary hyperparathyroidism: a retrospective study

AIM

TTo assess the effects of preoperative calcium levels and parathyroidectomy on estimated glomerular filtration rate (eGFR) in patients of primary hyperparathyroidism (PHPT) with mild renal dysfunction or normal renal function.

METHODS

This retrospective study enrolled 71 patients who underwent parathyroidectomy for PHPT in the General Surgery Department at Ondokuz Mayis University Hospital from 2010 to 2018. All patients were histopathologically diagnosed with parathyroid adenoma. Total serum calcium, serum creatinine, serum intact parathyroid hormone (PTH), and serum 25-hydroxyvitamin D3 (25(OH)D3) were measured before and 3-6 months after surgery. Patients were assigned to the low eGFR group (60-90 mL/min/1.73 m2) or normal eGFR group (≥90 mL/min/1.73 m2) and to the low calcium group (≤11.2 mg/dL) or high calcium group (>11.2 mg/dL).

RESULTS

In the low eGFR and high calcium group, there were significantly more patients with hypertension and older age. In the normal eGFR and high calcium group, eGFR was significantly reduced after surgery. Independent predictors of eGFR change after surgery were age, pre- parathyroidectomy calcium, and pre-parathyroidectomy eGFR.

CONCLUSIONS

After surgery, patients with low eGFR had preserved renal function, whereas those with normal eGFR had decreased renal function. Mild renal dysfunction in PHPT was associated with older age, hypertension, and high calcium levels.

Who Benefits from Treatment of Primary Hyperparathyroidism?

Parathyroidectomy (PTx) is the only definitive treatment for primary hyperparathyroidism (PHPT), but is commonly underutilized. Most patients are medically observed, whereas approximately 30% of patients are treated operatively. PTx is a low-risk surgical procedure and the most cost-effective treatment option. An international consensus statement was published in 1990 to guide clinicians in the management of patients with PHPT, particularly those with asymptomatic disease. Most patients with PHPT and low perioperative risk benefit from surgical treatment, regardless of whether they meet consensus criteria, due to fracture risk reduction, health-related quality-of-life improvements, and prevention or mitigation of disease progression.

End-organ effects of primary hyperparathyroidism: A population-based study

BACKGROUND

Patients with primary hyperparathyroidism are at risk for skeletal and renal end-organ damage.

METHODS

We studied patients with biochemically confirmed primary hyperparathyroidism from 1995-2014 and quantified the frequency of osteoporosis, nephrolithiasis, hypercalciuria, and decrease in renal function.

RESULTS

The cohort comprised 9,485 patients. In total, 3,303 (35%) had preexisting end-organ effects (osteoporosis, 24%; nephrolithiasis, 10%; hypercalciuria, 5%). Of 6,182 remaining patients, 1,769 (29%) exhibited progression to 1 or more end-organ effects over a median 3.7 years. Among patients with classic primary hyperparathyroidism (calcium and parathyroid hormone increased), progression was unrelated to the degree of hypercalcemia (calcium >11.5 mg/dL, hazard ratio 1.03, 95% confidence interval 0.85-1.25; 11.1-11.5 mg/dL, HR 1.07, 95% confidence interval 0.93-1.23; 10.5-11.0 mg/dL = reference). Patients with nonclassic primary hyperparathyroidism (calcium increased, parathyroid hormone 40-65 pg/mL) had a lesser risk of progression (calcium >11.5 mg/dL, hazard ratio 0.68, 95% confidence interval 0.50-0.94; 11.1-11.5 mg/dL, hazard ratio 0.68, 95% confidence interval 0.56-0.82; 10.5-11.0 mg/dL, hazard ratio 0.66, 95% confidence interval 0.59-0.74). End-organ damage developed before or within 5 years of diagnosis for 62% of patients.

CONCLUSION

End-organ manifestations of primary hyperparathyroidism develop before biochemical diagnosis or within 5 years in most patients. End-organ damage occurred more frequently in patients with classic primary hyperparathyroidism versus nonclassic primary hyperparathyroidism, regardless of severity of hypercalcemia.

High prevalence of chronic kidney disease in patients with multiple endocrine neoplasia type 1 and improved kidney function after parathyroidectomy

BACKGROUND

Because chronic kidney disease is an important comorbidity associated with primary hyperparathyroidism, we sought to evaluate the prevalence of chronic kidney disease and effects of parathyroidectomy on kidney function in patients with multiple endocrine neoplasia type 1-associated primary hyperparathyroidism.

METHODS

We performed a retrospective analysis of 112 patients with multiple endocrine neoplasia type 1-associated primary hyperparathyroidism who had at least 1 operation for primary hyperparathyroidism at 2 tertiary referral centers. The preoperative and postoperative estimated glomerular filtration rates were compared. The prevalence of chronic kidney disease stage 3 or worse (estimated glomerular filtration rates less than 60 mL/min/1.73m²) in this cohort was compared to the rates in the US population reported by the Centers for Disease Control and Prevention.

RESULTS

The median age at the time of parathyroidectomy was 36.5 years (range: 12-76 years). A total of 99 patients had biochemical remission. The rate of chronic kidney disease stage 3 or worse in patients with multiple endocrine neoplasia type 1-associated primary hyperparathyroidism was greater than that observed in the US population for ages 20-39 and 40-59 (5% [n = 2/44] vs 0.39% [n = 18/4565], P = .015 and 10% [n = 4/40] vs 2.31% (n = 89/3848), P = .015, respectively). We observed improved estimated glomerular filtration rates in those with chronic kidney disease stage 3 or worse postoperatively (48 vs 57 mL/min/1.73m², P = .047). A successful parathyroidectomy normalized all 24-hour urine calcium excretion.

CONCLUSION

An indication for early parathyroidectomy should include estimated glomerular filtration rates less than 60mL/min/1.73m² in patients with multiple endocrine neoplasia type 1-associated primary hyperparathyroidism.

Lower serum calcium levels are a risk factor for a decrease in eGFR in a general non-chronic kidney disease population

Association between serum calcium (Ca) levels and kidney dysfunction progression in a non-chronic kidney disease (CKD) population has not been well elucidated, especially in consideration for classical metabolic risk conditions such as hypertension, dyslipidemia, and diabetes, and those related to Ca metabolism. Among participants of the population-based Iwaki study of Japanese people, those with an estimated glomerular filtration rate (eGFR) ≧60 ml/min/1.73 m² and age ≧40 years, and who attended the study consecutively in 2014 and 2015 were enrolled (gender (M/F): 218/380; age: 58.9 ± 10.2). Regression analysis showed a significant correlation between serum Ca levels and a change in eGFR in the 1-year period (∆eGFR) after adjustment with multiple factors including those related to Ca metabolism (β = 0.184, p < 0.001). When subjects were stratified into tertiles based on their serum Ca levels (higher >9.6 mg/dL, middle 9.4–9.6 mg/dL, lower <9.4 mg/dL), lower serum Ca levels were a significant risk for a rapid decliner of eGFR designated as the lower one third of ∆eGFR (<−4.40 ml/min/1.73 m²) (odds ratio 2.41, 95% confidence interval 1.47–3.94). Lower serum Ca levels are a significant risk for rapid decrease in eGFR, independent of previously reported metabolic risk factors in this general population with non-CKD, or eGFR ≧60 ml/min/1.73 m².