The role of Rapid Intraoperative Parathyroid Hormone (ioPTH) assay in determining outcome of parathyroidectomy in primary hyperparathyroidism: A systematic review and meta-analysis.

BACKGROUND: Primary hyperparathyroidism (PHPT) is a common endocrine disorder. In the last few decades, the introduction of Rapid Intraoperative Parathyroid Hormone (ioPTH) monitoring has allowed to ensurance of the excision of all hyperfunctioning parathyroid tissues, reducing the risks of persistent and recurrent PHPT. However, the use of ioPTH is still debated among endocrine surgeons. MATERIAL AND METHODS: The objective of this systematic review and meta-analysis was to assess if ioPTH monitoring is able to reduce the incidence of persistent or recurrent PHPT. A systematic literature search was performed using PubMed, Scopus, ISI-Web of Science and Cochrane Library Database. Prospective and retrospective studies addressing the efficacy of ioPTH monitoring were included in the systematic review and meta-analysis. The random-effects model was assumed to account for different sources of variation among studies. The overall effect size was computed through the inverse variance method. Heterogeneity across studies, possible outlier studies, and publication bias were evaluated. RESULTS: A total of 28 studies with 13,323 patients were included in the quantitative analysis. The incidence of operative failure was 3.2% in the case group and 5.8% in the control group. After excluding three outlier studies, the quantitative analysis revealed that ioPTH reduced significantly the incidence of postoperative persistent or recurrent PHPT. (Risk Difference = -0.02; CI = -0.03, -0.01; p < 0.001). There was no evidence of heterogeneity among the studies (Q = 19.92, p = 0.70; I2 = 0%). The analysis of several continuous moderators revealed that the effectiveness of ioPTH was larger in studies with lower preoperative serum calcium values and higher incidences of multiple gland disease. CONCLUSION: ioPTH monitoring is effective in reducing the incidence of persistent and recurrent PHPT. Its routine use should be suggested in the next guidelines regarding management of PHPT.

Role of vitamin D supplements in prevention of hungry bone syndrome after successful parathyroidectomy for primary hyperparathyroidism: A prospective study.

BACKGROUND: We postulated that the preoperative correction of vitamin D levels can significantly reduce the incidence of hunger bone syndrome among patients undergoing parathyroidectomy for primary hyperparathyroidism. METHODS: We performed a prospective, randomized, open-label study on 102 patients with primary hyperparathyroidism and coexisting vitamin D deficiency who were scheduled to undergo parathyroidectomy. Patients were divided into the following two groups: group I which included 52 patients who did not receive preoperative vitamin D supplementation; and group II which included 50 patients who received cholecalciferol 1000-2000 IU daily or 50000 IU weekly until they achieve vitamin D levels >20 ng/mL (group IIa = 25 patients) or vitamin D levels >30 ng/mL (group IIb = 25 patients). RESULTS: The incidence of hunger bone syndrome in group IIb was lower than group I and group IIa (8% versus 16% versus 23%, respectively); however, this difference did not reach the level of statistical significance (p = 0.22). Patients with hunger bone syndrome were significantly younger and had higher serum phosphorus, alkaline phosphatase, magnesium, and bone mineral density at baseline than patients without hunger bone syndrome. On the other hand, patients with hunger bone syndrome had significantly lower 25-hydroxyvitamin D at baseline than patients without hunger bone syndrome (p = 0.001). The ROC curve showed that the baseline level of serum 25-hydroxyvitamin D was not an independent discriminator of hunger bone syndrome (area under curve = 0.21 (95% CI: 0.06-0.34); p = 0.011). CONCLUSIONS: Preoperative course of vitamin D supplements has no preventive role on the postoperative incidence of hunger bone syndrome among patients with primary hyperparathyroidism and coexisting vitamin D deficiency undergoing parathyroidectomy.

Pursuing the second ipsilateral gland during minimally invasive video-assisted parathyroidectomy.

BACKGROUND: In patients with primary hyperparathyroidism (PHPT) and preoperative imaging suggesting a solitary parathyroid adenoma (SPA), focused parathyroidectomy is most often curative. Even so, large studies show up to 3% of patients experience persistent or recurrent PHPT. Unilateral neck exploration (UNE) aiming to identify the SPA and the other ipsilateral parathyroid may reduce this failure rate. We hypothesized that: (i) minimally invasive video-assisted (MIVA) approach would facilitate UNE and (ii) this would be a clinically relevant strategy. METHODS: Prospective case series of a consecutive cohort of PHPT patients (with preoperative diagnosis of SPA), who underwent MIVA-UNE. A 15 mm collar incision and endoscopic magnification were utilized to both excise the SPA and seek the ipsilateral parathyroid gland. RESULTS: From 2009 to 2014, 132 patients were offered MIVA-UNE (age: 63.0 (interquartile range: 11.2); females: 94 (71.2%); symptomatic: 89 (67.4%); mean serum corrected calcium: 2.7 (standard deviation: 0.9) mmol/L; mean serum parathyroid hormone: 16.8 (standard deviation: 11.8) pmol/L). Conversion from MIVA-UNE to open UNE was required in 14 (10.6%) patients (excluded from subsequent analysis). MIVA-UNE was concluded in 118 patients. The second ipsilateral parathyroid was identified in 62 (52.5%) patients and in 13 (11.0%) it appeared enlarged and was excised. Histopathology confirmed five (4.2%) of these glands to be hyperplastic. CONCLUSION: MIVA-UNE allows identification of the second ipsilateral parathyroid in about half the patients. This approach helped to diagnose and treat unexpected multigland disease in almost 5% of patients.

Physical Activity and the Risk of Primary Hyperparathyroidism.

CONTEXT: Primary hyperparathyroidism (P-HPTH) is relatively common and predominantly affects women. Prior studies have shown that physical activity (PA) can lower PTH levels. OBJECTIVE: Our objective was to evaluate the hypothesis that lower PA is a risk factor for developing P-HPTH. DESIGN, SETTING, AND PARTICIPANTS: This prospective cohort study included 69 621 female participants in the Nurses' Health Study I followed for 22 years. EXPOSURES: PA and other dietary and demographic exposures were quantified via detailed, and validated, biennial questionnaires. OUTCOMES: Incident P-HPTH was confirmed by medical record review after initial assessment by questionnaire. Adjusted Cox proportional hazards models were used to evaluate whether PA was an independent risk factor for developing P-HPTH. We also evaluated the risk of developing P-HPTH when combining low PA (<16 metabolic equivalent hours/week) with a previously identified independent risk factor for developing P-HPTH: low calcium intake (<800 mg/day). The relation between PA and PTH levels was evaluated in 625 participants. RESULTS: We confirmed 302 incident cases of P-HPTH during 1 474 993 person-years of follow-up. Participants in the highest quintile (Q) of PA had a 50% lower risk of developing P-HPTH: age-adjusted relative risks and 95% confidence intervals for incident P-HPTH by lowest to highest of PA were Q1 = 1.0 (reference); Q2 = 0.83 (0.60­1.15); Q3 = 0.84 (0.61­1.15); Q4 = 0.50 (0.34­0.74); Q5 = 0.50 (0.35­0.73); P for trend <.001. Extensive multivariable adjustments did not materially change these findings. The adjusted relative risk for developing P-HPTH among participants with the combination lower PA and lower calcium intake was 2.37-fold (1.60­3.51) higher than in participants with higher PA and higher calcium intake. PA was inversely correlated with serum PTH (ρ = −0.09, P = .03); the mean adjusted serum PTH in Q 2­5 of PA was lower than in Q 1 (36.3 vs 39.1 pg/mL, P = .02). CONCLUSION: Low physical activity may be a modifiable risk factor for developing P-HPTH in women.

Normocalcemic hyperparathyroidism: preoperatively a disease, postoperatively cured?

BACKGROUND: Up to 44% of primary hyperparathyroidism patients have elevated parathyroid hormone (ePTH) with normal calcium postparathyroidectomy (PTx). The question is whether the surgical approach affects the incidence of this phenomenon. METHODS: Patients with hyperparathyroidism and presumed single-gland disease on preoperative imaging who underwent PTx between 1994 and 2008 were identified and contacted for long-term follow-up. PTx was either a focused approach (minimally invasive approach [MIP]) or a bilateral neck exploration (BNE). RESULTS: In total, 171 patients had PTH measured postoperatively (95 MIP and 76 BNE); 30 of 171 (17%) had ePTH with normal calcium (MIP 21 [22%] and BNE 9 [12%], P = .08). This occurred within 2 years in 48% and 67% and after 2 years in 52% and 33%, MIP vs BNE, respectively. Four patients recurred, 2 MIP and 2 BNE. CONCLUSIONS: There is a trend toward a higher incidence of ePTH in patients having undergone an MIP. The etiology of ePTH is multifactorial but may represent an early recurrence.

Primary hyperparathyroidism - is vitamin D supplementation safe?

BACKGROUND: Vitamin D deficiency is commonly seen in patients with primary hyperparathyroidism. However, there is a widespread reluctance to provide vitamin D supplementation to this group of patients. OBJECTIVE: This article examines the relationship between vitamin D deficiency and primary hyperparathyroidism and the effects of vitamin D supplementation. CONCLUSION: Vitamin D deficiency exacerbates primary hyperparathyroidism and vice versa. With care, vitamin D supplementation can safely be given to selected patients with asymptomatic primary hyperparathyroidism and is suggested before deciding on medical or surgical management. Monitoring serum calcium concentration and urinary calcium excretion is recommended while achieving vitamin D repletion.

Variation in plasma calcium analysis in primary care in Sweden--a multilevel analysis.

BACKGROUND: Primary hyperparathyroidism (pHPT) is a common disease that often remains undetected and causes severe disturbance especially in postmenopausal women. Therefore, national recommendations promoting early pHPT detection by plasma calcium (P-Ca) have been issued in Sweden. In this study we aimed to investigate variation of P-Ca analysis between physicians and health care centres (HCCs) in primary care in county of Skaraborg, Sweden. METHODS: In this cross sectional study of patients' records during 2005 we analysed records from 154 629 patients attending 457 physicians at 24 HCCs. We used multilevel logistic regression analysis (MLRA) and adjusted for patient, physician and HCC characteristics. Differences were expressed as median odds ratio (MOR). RESULTS: There was a substantial variation in number of P-Ca analyses between both HCCs (MORHCC 1.65 [1.44-2.07]) and physicians (MORphysician 1.95 [1.85-2.08]). The odds for a P-Ca analysis were lower for male patients (OR 0.80 [0.77-0.83]) and increased with the number of diagnoses (OR 25.8 [23.5-28.5]). Sex of the physician had no influence on P-Ca test ordering (OR 0.93 [0.78-1.09]). Physicians under education ordered most P-Ca analyses (OR 1.69 [1.35-2.24]) and locum least (OR 0.73 [0.57-0.94]). More of the variance was attributed to the physician level than the HCC level. Different mix of patients did not explain this variance between physicians. Theoretically, if a patient were able to change both GP and HCC, the odds of a P-Ca analysis would in median increase by 2.45. Including characteristics of the patients, physicians and HCCs in the MLRA model did not explain the variance. CONCLUSIONS: The physician level was more important than the HCC level for the variation in P-Ca analysis, but further exploration of unidentified contextual factors is crucial for future monitoring of practice variation.