Racial Disparities in Primary Hyperparathyroidism.

BACKGROUND: Racial disparities in surgery are increasingly recognized. We evaluated the impact of race on presentation, preoperative evaluation, and surgical outcomes for patients undergoing parathyroidectomy for primary hyperparathyroidism (PHPT). METHODS: We performed a retrospective cohort study of patients undergoing parathyroidectomy for PHPT at a single center (1997-2015). Patients were classified by self-identified race, as African-American or White. The primary outcome was disease severity at referral. The secondary outcome was completeness of preoperative evaluation. Operative success and surgical cure were evaluated. RESULTS: A total of 2392 patients were included. The majority of patients (87.6%) were White. African-American patients had higher rates of comorbid disease as well as higher preoperative calcium (10.9 vs.10.8 mg/dl, p < 0.001) and PTH levels (122 vs. 97 pg/ml, p < 0.001). White patients were more likely to have history of bone loss documented by DXA and nephrolithiasis. African-American patients had lower rates of complete preoperative evaluation including DXA scan. Operatively, African-American patients had larger glands by size (1.7 vs. 1.5 cm, p < 0.001) and mass (573 vs. 364 mg, p < 0.001). We observed similar operative success (98.9 vs. 98.0%, p = 0.355) and cure rates (98.3 vs. 97.0%, p = 0.756). CONCLUSIONS: At the time of surgical referral, African-American patients with PHPT have more biochemically severe disease and higher rates of incomplete evaluation. Operative success and cure rates are comparable.

IMPACT OF ETHNIC BACKGROUND ON CLINICAL CHARACTERISTICS AND CARDIOVASCULAR RISK FACTORS AMONG PATIENTS WITH PRIMARY HYPERPARATHYROIDISM.

OBJECTIVE: To compare initial laboratory values and cardiovascular risk factors (CRF) among patients with primary hyperparathyroidism (PHPT) of different ethnic backgrounds. METHODS: In this retrospective study, we reviewed 500 charts of PHPT patients who presented at Robert Wood Johnson University Hospital from January 2000 to December 2013. Among these patients were 46 African Americans (AA), 31 Asians (A), 19 Hispanics (H), and 404 Caucasians (C). The following characteristics were compared between the groups: age; body mass index (BMI); levels of serum calcium, intact parathyroid hormone (iPTH), 25-OH vitamin D, and 24-hour urine calcium; and parathyroid adenoma weight. Presence of CRF including BMI, diabetes mellitus, hypertension, and hyperlipidemia were also recorded for comparison. Associations of adenoma weight and several other parameters were also assessed. RESULTS: Among different ethnic groups, AA patients with PHPT had higher iPTH levels compared to the A and C groups (P<.05), while 25-OHD levels were lower in the AA compared to the A and C groups (P<.05). Adenoma weight was significantly greater in AA than in C and A PHPT patients (P<.01). Adenoma weight was positively correlated with iPTH levels (r = 0.493, P <.001) and serum calcium levels (r = 0.255, P<.01). The group BMIs were C: 29.5 ± 6.9, AA: 33.8 ± 10, A: 24.7 ± 3.3, and H: 30.2 ± 6.6. AA patients had a lower rate of renal stones (9%) compared to other groups (21-29%, P<.05). CONCLUSION: The results of our study indicate that AA patients with PHPT presented with a more severe PHPT profile but had lower 24-hour urine calcium and fewer renal stones. AA patients with PHPT also had higher prevalence of CRF when compared to A and C.

High serum parathyroid hormone and calcium are risk factors for hypertension in Japanese patients.

Excess parathyroid hormone (PTH), known as primary hyperparathyroidism (pHPT), results in hypercalcemia and bone loss. Recent studies have shown that PTH is associated with the occurrence of hypertension in Western countries; however, controversy remains regarding high serum levels of PTH and calcium as risk factors for hypertension in Japanese patients. We retrospectively enrolled 114 consecutive Japanese patients who visited our hospital for examination and treatment of hypercalcemia and/or hypertension with serum calcium levels ≥ 9.8 mg/dL. To estimate the prevalence of hypertension, the patients were categorized according to calcium levels into hypercalcemic (10.2-13.4 mg/dL) and normocalcemic (9.8-10.1 mg/dL) groups, which were further categorized into high PTH (50-440 pg/mL) and low PTH (8-49 pg/mL) groups. The prevalence of hypertension was higher in patients with hypercalcemia than in patients with normocalcemia in both the high and low PTH groups. The prevalence of hypertension was higher in patients with high serum PTH levels than in patients with low serum PTH levels in both the hypercalcemic and normocalcemic groups. Logistic multiple regression analysis determined that serum calcium (P < 0.05) and PTH (P < 0.01) levels were positive contributors to hypertension. In conclusion, high serum levels of PTH and calcium are risk factors for hypertension in Japanese patients.

Use and disparities in parathyroidectomy for symptomatic primary hyperparathyroidism in the Medicare population.

BACKGROUND: Few studies assess use of parathyroidectomy among older adults with symptomatic primary hyperparathyroidism. Our objective was to determine national usage and disparities in parathyroidectomy for symptomatic primary hyperparathyroidism among insured older adults. METHODS: We identified older adult patients with symptomatic primary hyperparathyroidism using Medicare claims (2006-2017). Primary study variables were race/ethnicity, rurality, and zip-code socioeconomic status. We calculated cumulative incidence of parathyroidectomy and used multivariable Cox proportional hazards regression models to assess the adjusted association of our study variables with parathyroidectomy. RESULTS: We included 94,803 patients. The median age at primary hyperparathyroidism diagnosis was 76 years (interquartile range 71-82). The majority of patients were female (72%), non-Hispanic White (82%), from metropolitan areas (82%), and had a Charlson Comorbidity score ≥3 (62%). Nine percent of patients (n = 8,251) underwent parathyroidectomy during follow-up. After adjustment, non-Hispanic Black patients, compared to non-Hispanic White (hazard ratio 0.80; 95% confidence interval 0.74, 0.87), and living in a low socioeconomic status neighborhood (low socioeconomic status vs highest socioeconomic status hazard ratio 0.89; 95% confidence interval 0.83, 0.95) were both associated with lower incidences of parathyroidectomy. Patients from non-metropolitan areas were more likely to undergo parathyroidectomy. CONCLUSION: Parathyroidectomy is underused for symptomatic primary hyperparathyroidism in older adults. Quality improvement efforts, rooted in equitable care, should be undertaken to increase access to parathyroidectomy for this disease.

Ethnic and economic disparities effect on management of hyperparathyroidism.

BACKGROUND: Successful parathyroidectomy requires advanced surgeon experience. We aim to examine population characteristics at risk of being managed by low-volume surgeons. METHODS: A cross-sectional study was performed utilizing the Nationwide Inpatient Sample database, 2004 to 2009. The study population included adult inpatients who underwent parathyroidectomy for primary hyperparathyroidism. RESULTS: A total of 3,503 discharge records were included. Men, Hispanics, and those with Medicaid/Medicare health coverage were more likely to be managed by low-volume surgeons (P < .05 each). Low-volume surgeons were more likely to operate in rural (odds ratio [OR], 3.99; 95% confidence interval [CI], 1.95 to 8.16; P < .001) or nonteaching hospitals (OR, 2.15; 95% CI, 1.42 to 3.27; P < .001). Southern region of the United States had a high prevalence of low-volume surgeons compared with other regions (Southern: 51.3%, Northeast: 24.3%, Midwest: 25.6%, and West: 27.6%, P < .001). Operations by the low-volume surgeons associated with a higher risk of postoperative complications (OR, 1.81; 95% CI, 1.11 to 2.97) and a hospital stay more than 2 days (OR, 7.12; 95% CI, 3.75 to 13.45; P < .001). CONCLUSIONS: Certain populations are at risk of management by low-volume surgeons based on their demographic and economic characteristics.

A pilot study to examine the management of asymptomatic hyperparathyroidism in Japanese patients in accordance with the guidelines for asymptomatic PHPT proposed at the Third International Workshop in 2008.

Objective The treatment for asymptomatic primary hyperparathyroidism (PHPT) remains controversial. In 2008, the Third International Workshop on the Management of Asymptomatic PHPT proposed a set of guidelines for the management of asymptomatic PHPT. We therefore evaluated the application of the Workshop recommendations in Japanese patients with asymptomatic PHPT. Methods We analyzed each parameter of the guidelines in 87 Japanese patients with asymptomatic PHPT who underwent methoxy-isobutyl-isonitrile (MIBI) scintigraphy. Results Fewer than 10% of the patients were less than 50 years of age. The bone mineral density T-score was below -2.5 SD in 20 women (46.5% of all women analyzed) and in none of the men. The eGFR was <60 mL/min/1.73 m(2) in 17 patients. A majority of patients (43) satisfied only one parameter, while 25 patients satisfied none of the parameters. Furthermore, the MIBI-positive and surgically treated patients tended to satisfy a larger number of the parameters. The Workshop criteria and levels of PTH, daily Ca excretion, serum ALP and 1,25(OH)2 Vitamin D were further analyzed in relation to the findings of MIBI scans, and almost all of the parameters were found to be significantly correlated with the results of the MIBI studies. Conclusion Our results suggest the need to reassess the Workshop guidelines for the treatment of hyperparathyroidism in Japanese patients. It is desirable that MIBI scintigraphy be performed whenever possible, as this modality is anticipated to play an important role in determining whether or not surgery is appropriate.

Incidence and prevalence of primary hyperparathyroidism in a racially mixed population.

CONTEXT: The epidemiology of primary hyperparathyroidism (PHPT) has generally been studied in Caucasian populations. OBJECTIVE: The aim was to examine the incidence and prevalence of PHPT within a racially mixed population. DESIGN: A descriptive epidemiologic study was performed. PATIENTS/SETTING: The study population included 3.5 million enrollees within Kaiser Permanente Southern California. METHODS: All patients with at least one elevated serum calcium level (>10.5 mg/dL, 2.6 mmol/L) between 1995 and 2010 were included. Cases of PHPT were identified by electronic query of laboratory values using biochemical criteria, after exclusion of secondary or renal and tertiary hyperparathyroidism cases. The incidence and prevalence rates of PHPT were calculated according to sex, race, age group by decade, and year. RESULTS: Initial case finding identified 15,234 patients with chronic hypercalcemia, 13,327 (87%) of which had PHPT as defined by elevated or inappropriately normal parathyroid hormone levels. The incidence of PHPT fluctuated from 34 to 120 per 100,000 person-years (mean 66) among women, and from 13 to 36 (mean 25) among men. With advancing age, incidence increased and sex differences became pronounced (incidence 12-24 per 100,000 for both sexes younger than 50 y; 80 and 36 per 100,000 for women and men aged 50-59 y, respectively; and 196 and 95 for women and men aged 70-79 y, respectively). The incidence of PHPT was highest among blacks (92 women; 46 men, P < .0001), followed by whites (81 women; 29 men), with rates for Asians (52 women, 28 men), Hispanics (49 women, 17 men), and other races (25 women, 6 men) being lower than that for whites (P < .0001). The prevalence of PHPT tripled during the study period, increasing from 76 to 233 per 100,000 women and from 30 to 85 per 100 000 men. Racial differences in prevalence mirrored those found in incidence. CONCLUSIONS: PHPT is the predominant cause of hypercalcemia and is increasingly prevalent. Substantial differences are found in the incidence and prevalence of PHPT between races.

Primary hyperparathyroidism and vitamin D in African Americans.

OBJECTIVES: Vitamin D deficiency is more common in African Americans than in the general population or other ethnicities. Vitamin D deficiency also occurs more frequently in patients with primary hyperparathyroidism (PHPT) than in the general population. Currently, the limited data on vitamin D deficiency in African Americans with primary hyperparathyroidism (PHPT) is inconsistent as to whether the vitamin D deficiency observed in PHPT is yet even more pronounced in Africans with PHPT relative to non-African Americans with PHPT. METHODS: On the basis of biochemical, radiological, and surgical (adenoma weight) parameters, African Americans have been reported to have a more severe form of PHPT than non-African Americans. However, comparative clinical manifestations of PHPT in African Americans have not been well described. RESULTS: Current guidelines recommend vitamin D repletion in mild, asymptomatic PHPT when levels of 25-hydroxyvitamin D are less than 20 ng/mL. Studies that reported vitamin D repletion with ergocalciferol or cholecalciferol in PHPT have not stratified data according to ethnicity. Discrepancies therefore exist between repleting vitamin D in African Americans who may potentially have a more severe PHPT profile, but simultaneously a more pronounced vitamin D deficiency. CONCLUSION: Effectively designed clinical trials are necessary to evaluate the indications, efficacy, and safety of vitamin D in African Americans with PHPT.

Low urine calcium excretion in African American patients with primary hyperparathyroidism.

OBJECTIVE: To evaluate the prevalence of low urine calcium excretion in African American patients with primary hyperparathyroidism (PHPT), a common disorder associated with bone and renal complications, and to assess the distinction between PHPT and familial hypocalciuric hypercalcemia (FHH), a rare benign genetic disease. METHODS: We conducted a retrospective study on a cohort of 1,297 patients in whom a 24-hour urine study was performed for measurement of urine calcium and creatinine. PHPT was diagnosed if the serum calcium concentration was ≥10.5 mg/dL and intact parathyroid hormone (PTH) was ≥40 pg/mL. Patients receiving medications that affect urine calcium or with glomerular filtration rate ≤30 mL/min were excluded. RESULTS: Ninety-six patients satisfied the diagnostic criteria for PHPT. The African American (n = 70) and non-African American (n = 26) patients did not differ in their mean age, body mass index, glomerular filtration rate, serum PTH, 25-hydroxyvitamin D levels, and 24-hour urine creatinine values. Median values of urine calcium/creatinine (mg/g) were 122 for African American versus 214 for non-African American patients (P = .006). Thirty-one of 70 African American patients (44%) had a urine calcium/creatinine ratio ≤100 mg/g, whereas only 2 of 26 non-African American patients (8%) had this value (P = .001). CONCLUSION: The prevalence of low urine calcium excretion among African American patients with PHPT is unexpectedly high. A threshold of 100 mg/g urine calcium/creatinine identified 44% of such patients with PHPT as having FHH in this cohort. Therefore, other clinical criteria and laboratory variables should be used to distinguish PHPT from FHH in African American patients with PTH-dependent hypercalcemia.

African Americans present with more severe primary hyperparathyroidism than non-African Americans.

BACKGROUND: Similar to other disease states, we postulated that African American patients present with more severe signs of primary hyperparathyroidism than non-African Americans. To test this hypothesis, we compared relevant preoperative laboratory values, sestamibi scan results, and intraoperative findings between African American and non-African American patients with primary hyperparathyroidism who underwent parathyroidectomy between January 2002 and May 2007. METHODS: In all, 588 patients were included and 113 (19%) were African American. A linear model was used to examine the effect of race with respect to mean differences in serum calcium, 25-hydroxyvitamin D (25(OH)D), intact parathyroid hormone (iPTH), alkaline phosphatase (ALKP) levels, gland weight, presence of double adenomas and, sestamibi scan sensitivity. RESULTS: Adjusted for age and gender, African Americans exhibited significantly higher median calcium (11.36 [SD = 0.91] vs 11.06 [SD = 0.72] mg/dL, P < .001), iPTH (138.5 [SD = 166.03] vs 117 [73.22] pg/mL, P < .01), and ALKP (101 [SD = 57.86] vs 90.5 [SD = 29.78] U/L, P < .01) levels compared with non- African Americans. They exhibited significantly lower median serum 25(OH)D (14 [SD = 9.36] vs 23 [SD = 12.160] ng/mL, P < .001), greater gland weight (P < .001), a higher probability of double adenomas (odds ratio = 2.83, 95% confidence interval [CI], 1.36-5.88), and a higher probability of presenting with a positive sestamibi scan (odds ratio = 4.99, 95% CI = 2.44-10.19) compared with non-African Americans. CONCLUSION: African Americans present with more advanced signs of primary hyperparathyroidism than non-African Americans. These results may reflect less access to health care, surgical consultations, or other unidentified factors. These highly significant findings, however, warrant additional investigation.

Prevalence of type 2 diabetes mellitus in patients with primary hyperparathyroidism.

INTRODUCTION: To determine the prevalence of type 2 diabetes mellitus (DM) in patients with primary hyperparathyroidism. METHODS: Prevalence of type 2 DM in 609 patients with surgically verified primary hyperparathyroidism presenting between 1992 and 2003 in a tertiary care hospital setting was assessed retrospectively and compared with published data of type 2 DM prevalence in Michigan's general population. Diagnosis of type 2 DM was made on the basis of documentation in the medical record of fasting or random blood glucose level thresholds according to the 1997 American Diabetes Association criteria, history of diabetes mellitus, or therapy with antidiabetic medications. RESULTS: The crude prevalence rate of type 2 DM in patients with primary hyperparathyroidism was significantly higher than the prevalence in the Michigan general population (15.9% vs 7.8%, respectively; P<.001). However, this difference was not significant after age stratification except for the age group of 64 to 75 years. Because of the differential distribution of participants across age categories in the 2 groups, a standardized prevalence ratio (SPR) was estimated to account for the variance. After adjustment, there was no significant difference in the prevalence of DM between patients with primary hyperparathyroidism and the control population (SPR, 1.19 [95% confidence interval, 0.96-1.45]) except in men. CONCLUSION: The reported higher prevalence of type 2 DM in patients with primary hyperparathyroidism could not be confirmed in this large cohort of patients except for in older patients and in men. Because of the retrospective nature the study and the lack of appropriate controls, further studies are needed to confirm or refute these findings.