Abstract
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 2,392 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.
Keywords: Primary hyperparathyroidism, race, disparity
Introduction
Primary hyperparathyroidism (PHPT) is a common endocrine disorder. In a racially mixed population, the incidence was found to be 66 per 100,000 person-years among women, with highest prevalence among African-Americans [1]. PHPT can cause end-organ dysfunction including bone mineral density loss, nephrolithiasis, and renal insufficiency, as well as gastrointestinal and neurocognitive symptoms [2]. Parathyroidectomy is the only cure for PHPT, and is indicated for symptoms and for evidence of end-organ dysfunction. Even among initially asymptomatic patients, more than a third develop symptoms over time [3, 4]. Surgery can improve patient quality of life and is the most cost-effective management strategy for primary hyperparathyroidism [5, 6].
Racial disparities in medicine are increasingly recognized, with a growing body of research investigating the relationship between race, disease severity, and outcomes. African-American patients have worse outcomes than white patients in colon cancer, lung cancer, and cardiovascular disease [7-9]. Racial disparities in patient presentation, management and outcomes have also been reported across surgical specialties [10-13]. Multiple factors, including delays in diagnosis, differences in management, and disparities in access to care may contribute to poorer outcomes in African-American patients compared to White patients.[14]
Race has been identified as an important factor influencing surgical outcomes in thyroidectomy and parathyroidectomy. African-American patients undergoing thyroidectomy and parathyroidectomy have been shown to have increased mean length of stay, in-hospital mortality and a trend towards higher complication rates [15, 16]. Although surgical outcomes have been well-studied, racial disparities in initial presentation and disease-severity has not been extensively evaluated in primary hyperparathyroidism. Therefore, the goal of the present study is to evaluate the association between race, disease severity, and completeness of clinical evaluation in PHPT patients presenting for parathyroidectomy.
Materials and Methods
Study Population:
We performed a retrospective cohort study of patients undergoing initial parathyroidectomy for PHPT at our institution from 1997-2015 (n=2,987). Patients were classified as White, African-American, Asian, or Other based on self-identified race, by United States Census categories.[17] No patients self-identifying as Native Hawaiian/Pacific Islander or Native American/Alaskan Native met initial inclusion criteria. Patients self-identifying as Other or mixed race were excluded due to population heterogeneity. Patients self-identifying as Asian were excluded due to low group number. In addition to race, patients could self-identify by ethnicity as Hispanic-Latino or Non-Hispanic Non-Latino. Patients were not excluded based on ethnicity. Patients who identified as White or African-American were included in final analysis (n=2,392). Patients who self-identified as White race and Hispanic-Latino ethnicity were included in the White group, and those who self-identified as African-American race and Hispanic-Latino ethnicity were included in the African-American group. This study was approved by the Institutional Review Board of the University of Pennsylvania (protocol #831194).
Variables:
Patient data was collected prospectively from the electronic medical record and stored in quality assurance databases. Demographic and clinical variables included age, gender, self-reported race, biochemical and imaging data, and surgical pathology. Glomerular filtration rate (GFR) was calculated using the Modification of Diet in Renal Disease (MDRD) Study equation. A modified Elixhauser Comorbidity Index was calculated for all patients using ICD-9/10 codes for 31 defined comorbidities [18]. To estimate median income as a marker of socioeconomic status, patient zip code data was matched to median household income data compiled from geographic level Census Bureau data (2006-2010) accessed via the Population Studies Center Institute for Social Research at the University of Michigan [19].
Definitions & Outcomes:
The primary study outcome was severity of disease at presentation. Disease severity was defined as a combination of biochemical results and presence of symptoms. A complete preoperative biochemical evaluation included serum calcium, 24-hour urine calcium, serum PTH, creatinine, and GFR. Signs and symptoms of PHPT included nephrolithiasis and/or nephrocalcinosis, osteoporosis, and other systemic symptoms including fatigue, memory loss, mood changes, depression, and joint pain.
The secondary outcome was completeness of diagnostic evaluation prior to surgical referral. Complete preoperative evaluation included preoperative biochemical evaluation (as above) and dual-energy X-ray absorptiometry (DXA) scan in accordance with published guidelines [20]. Bone mineral density (BMD) loss was classified as lowest T-score on DXA more than one standard deviation below NHANES controls, consistent with standard clinical definitions. Dual preoperative imaging was defined as combined technetium-99 sestamibi scan and cervical ultrasound, which has demonstrated increased accuracy and sensitivity and is consistent with our institutional practice.
Other outcomes included operative success and operative cure. Operative success was defined as a decrease of >50% in final intraoperative parathyroid hormone levels (IOPTH) [21]. Cure was defined as eucalcemia ≥6 months after parathyroidectomy [20]. Gland Size was defined by measurement of the dominant abnormal gland and was recorded as both mass (milligrams) and size by greatest dimension (cm).
Intraoperative Parathyroid Hormone Monitoring (IOPTH):
Intraoperative serum parathyroid hormone (PTH) levels were obtained by venipuncture prior to incision and 15 minutes after excision of abnormal parathyroid gland(s). Testing was performed in the clinical laboratories of the University of Pennsylvania on an Immulite® 2000 Immunoassay System (Siemens Healthcare, Erlangen, Germany) with chemiluminescent immunoassay detection of intact PTH.
Statistics:
Descriptive statistics were performed; subjects with missing data were excluded from frequency counts, and denominators were reported to provide numbers of patients with available data. Group comparisons utilized the chi-squared test or the Fisher’s exact test for parametric comparisons, or the Wilcoxon rank-sum test, for non-parametric comparisons. Continuous variables were reported as mean ± standard deviation (SD) or median with interquartile interval (IQI) for normally distributed and non-normally distributed variables, as appropriate. Assuming alpha of 0.05, beta 0.80, and standard deviation of 0.7 mg/dl, the study cohort was powered to detect a 0.12 mg/dl difference in preoperative serum calcium levels. Assuming alpha of 0.05, beta 0.80, and standard deviation of 0.6 mg/dl, the study cohort was powered to detect a 0.14 mg/dl difference in calcium levels ≥6 months after surgery. Univariate linear regression was performed to determine associations between independent covariates and parathyroid gland size and weight. Covariates meeting nominal significance (p≤0.20) on univariate regression were included in a backward stepwise multivariate linear regression model. Statistical analysis was performed using STATA 15.1 (Stata Corporation, College Station, TX). P-values are two-tailed unless otherwise indicated. A p- value ≤0.05 was considered significant.
Results
Clinical characteristics
Of the 2,392 patients included in the study, 296 (12.4%) self-identified as African-American (Table 1). The median age was 59 years (IQI 52, 68) and the majority were female (77.7%, 1859/2392). A majority of patients (69.7%, 1648/2366) had systemic symptoms (fatigue, memory loss, mood changes, depression, or joint pain) at the time of presentation. A majority (73.1%, 1272/1741) also had BMD loss. A significant minority of patients (20.3%, 481/2364) had a history of nephrolithiasis.
Table 1.
Characteristics of patients (n = 2,392) with primary hyperparathyroidism undergoing parathyroidectomy
| Characteristic | N or median |
|---|---|
| Age in years (median, IQI) | 59 (52, 68) |
| Female (n, %) | 1,859 (77.7%) |
| African American (n, %) | 296 (12.4%) |
| Clinical presentation (n, %) | |
| Nephrolithiasis | 481 (20.4%) |
| Bone mineral density loss | 1,272 (73.1%) |
| Systemic symptoms | 1,648 (69.7%) |
| Preoperative Biochemical Evaluation | |
| Calcium, mg/dl (median, IQI) | 10.8 (10.4, 11.2) |
| 24-hour urine calcium, mg (median, IQI) | 289 (189, 408) |
| PTH, pg/ml (median, IQI) | 99 (74, 136) |
| Creatinine, mg/dl (median, IQI) | 0.8 (0.7, 1.0) |
| GFR, ml/min/1.73 m2 (median, IQI) | 76 (64, 90) |
SD – Standard deviation; IQI – Interquartile interval; PTH – Parathyroid hormone; GFR – Glomerular filtration rate
On preoperative biochemical testing, median serum calcium was 10.8 mg/dl (IQI 10.4, 11.2), 24-hour urinary calcium was 289 mg (IQI 189, 408) and serum PTH was 99 pg/ml (IQI 74, 136). Median creatinine was 0.8 mg/dl (IQI 0.7, 1.0) and median GFR was 76 ml/min/1.73 m2 (IQI 64, 90).
Analysis by race
Patients were classified as White (87.6%, 2096/2392) or African-American (12.4%, 296/2392) based on self-identified race (Table 2). There was no significant difference in median age between the two groups (59 vs. 59, p=0.632). The majority of patients in both groups were female gender, however a larger percentage of the African-American patients were female (84.5% (250/296) vs. 76.8% (1609/2096), p=0.003). African-American patients had significantly higher numbers of comorbid medical conditions at presentation, as quantified by median Elixhauser score (1.0 vs. 0.0, p<0.001). There was no difference between groups in terms of family history of PHPT or personal diagnosis of multiple endocrine neoplasia. African-American patients had a significantly lower matched median income ($44,276 vs. $80,178, p<0.001). The most common insurance type was a commercial payer, followed by Medicare. African-American patients had a higher proportion of commercial insurance (80.7% (239/296) vs. 75.4% (1581/2096)) and of Other insurance (predominantly Medicaid, 1.4% (4/296) versus 0.7% (14/2096)) p=0.025 when compared to White patients.
Table 2.
Preoperative characteristics, by race
| African American (n = 296) |
White (n = 2096) |
p-value | |
|---|---|---|---|
| Characteristic | |||
| Age (median, IQI) | 59 (51, 68) | 59 (52, 68) | 0.636 |
| Female gender (n, %) | 250 (84.5) | 1609 (76.8) | 0.003 |
| Elixhauser score (median, IQI) | 1 (0, 2) | 0 (0, 1) | <0.001 |
| Family history of PHPT (n, %) | 4 (1.4) | 36 (1.9) | 0.811 |
| Multiple endocrine neoplasia (n, %) | 3 (1.0) | 27 (1.3) | 1.000 |
| Primary payer (n, %) | 0.025 | ||
| Medicare | 53 (17.9) | 501 (23.9) | |
| Commercial | 239 (80.7) | 1581 (75.4) | |
| Other | 4 (1.4) | 14 (0.7) | |
| Median Income, USD (median, IQI) | 44276 (31088, 67049) | 80178 (61503, 95181) | <0.001 |
| Signs & Symptoms: | |||
| Nephrolithiasis (n, %) | 41 (14.0) | 440 (21.2) | 0.004 |
| Bone mineral density loss (n, %) | 109 (59.9) | 1163 (74.6) | <0.001 |
| Systemic symptoms (n, %) | 212 (72.4) | 1436 (69.3) | 0.283 |
| Preoperative Labs: | |||
| Calcium, mg/dl (median, IQI) | 10.9 (10.5, 11.4) | 10.8 (10.4, 11.2) | <0.001 |
| 24-hour urine calcium, mg (median, IQI) | 260 (170, 361) | 293 (191, 414) | 0.022 |
| Intact PTH, pg/ml (median, IQI) | 122 (85, 176) | 97 (73, 130) | <0.001 |
| Creatinine, mg/dl (median, IQI) | 0.9 (0.7, 1.1) | 0.8 (0.7, 1.0) | <0.001 |
| GFR, ml/min/1.73 m2 (median, IQI) | 84 (65, 102) | 76 (64, 89) | <0.001 |
| Preoperative Evaluation: | |||
| 24-hour urinary calcium (n, %) | 143 (48.3) | 1047 (50.0) | 0.597 |
| DXA scan (n, %) | 182 (61.5) | 1559 (74.4) | <0.001 |
| Sestamibi only (n, %) | 52 (17.6) | 362 (17.3) | 0.900 |
| Ultrasound only (n, %) | 19 (6.4) | 51 (2.4) | <0.001 |
| Sestamibi & ultrasound (n, %) | 202 (68.2) | 1543 (73.6) | 0.051 |
SD – Standard deviation; USD – United States Dollar; IQI – Interquartile interval; PTH – Parathyroid hormone; GFR – Glomerular filtration rate; DXA – Dual-energy X-ray absorptiometry
Statistically significant results in bold
There were significant differences in the presenting signs and symptoms between groups. Nephrolithiasis was present in a minority of patients and was significantly less common among African-American compared to White patients (14.0% (41/292) vs. 21.2% (440/2072), p=0.004). Among patients who had a DXA scan, BMD loss was less common in African-American patients when compared with White patients (59.9% (109/182) vs. 74.6% (1163/1559), p<0.001). However, there was no statistically significant difference in prevalence of reported systemic symptoms between groups (72.4% (212/293) vs. 69.3% (1436/2073), p=0.283).
African-American patients had a significantly higher median preoperative calcium (10.9 vs. 10.8 mg/dl, p<0.001) as well as 26% higher median PTH levels (122 vs. 97 pg/ml, p<0.001) compared to White patients. African-American patients had lower preoperative 24-hour urinary calcium levels compared to White patients (260 vs. 293 mg, p=0.022). There was no significant difference in rates of completed 24-hour urine calcium studies (48.3% (143/296) vs. 50.0% (1047/2096), p=0.597). African-American patients had higher preoperative GFR (84 vs. 76 ml/min/1.73 m2, p<0.001).
African-American patients had lower rates of complete preoperative evaluation. African-American patients were less likely to have had a completed DXA scan (61.5% (182/296) vs. 74.4% (1559/2096), p<0.001). African-American patients were less likely to have undergone both Sestamibi and neck ultrasound; this difference approached statistical significance (68.2% (202/296) vs. 73.6% (1543/2096), p=0.051). African-Americans were more likely to have an ultrasound as their only preoperative imaging (6.4% (19/296) vs. 2.4% (51/2096), p<0.001).
Operative Findings & Clinical Outcomes
Operative data was compared between White and African-American patients, according to self-identified race (Table 3). There was no difference in rates of minimally invasive operative approach in African-American patients compared to White patients (37.2% (110/296) vs. 33.1% (694/2096), p=0.169). There was no difference in final diagnosis between African-American and White patients (p=0.887); the most common diagnosis in both groups was a single adenoma. On final pathology, African-American patients were found to have significantly larger dominant abnormal glands: parathyroid gland size was 13% larger (1.7 vs. 1.5 cm, p<0.001) and gland mass was 57% greater (573 vs. 364 mg, p<0.001) when compared to White patients.
Table 3.
Operative findings, by race
| African American (n = 296) |
White (n = 2096) |
p-value | |
|---|---|---|---|
| Operative approach (n, %) | 0.169 | ||
| Minimally invasive | 110 (37.2%) | 694 (33.1%) | |
| Bilateral neck exploration | 186 (62.8%) | 1401 (66.9%) | |
| Gland Characteristics (median, IQI) | |||
| Size, cm | 1.7 (1.3, 2.2) | 1.5 (1.1, 1.9) | <0.001 |
| Mass, mg | 573 (300, 1228) | 364 (180, 793) | <0.001 |
| Final diagnosis (n, %) | 0.887 | ||
| Single adenoma | 240 (81.1%) | 1693 (80.8%) | |
| Double adenoma | 29 (9.8%) | 195 (9.3%) | |
| Hyperplasia | 27 (9.1%) | 208 (9.9%) | |
| Ectopic gland (n, %) | 30 (10.1%) | 210 (10.0%) | 0.950 |
IQI – Interquartile interval
Statistically significant results are given in bold
Clinical outcomes were also compared between groups (Table 4). There was no difference in operative success between groups (98.9% (275/278) vs. 98.0% (1912/1952), p=0.355). There was no significant difference in overall duration of follow-up between groups (8 vs. 6 months, p=0.065). For the 626 subjects with complete biochemical testing performed ≥6 months after surgery, the median follow-up time was 34 months. Duration of long-term follow-up did not differ between groups (32 vs. 34 months, p=0.927). Despite a significantly higher median serum PTH at long-term follow-up in African-American patients (58 vs. 44 pg/ml, p<0.001), both groups had PTH levels in the normal range. At long-term follow-up, there was no significant difference in median serum calcium levels between groups (9.4 vs. 9.5 mg/dl, p=0.577), and both groups were in the normal range; group size may have been underpowered to detect a 0.1 mg/dl difference in calcium levels. Long-term cure rates were similar (98.3% (113/115) vs. 97.0% (582/600), p=0.756) in African-American and White patients, respectively.
Table 4.
Clinical outcomes, by race
| African American (n = 296) |
White (n = 2096) |
p-value | |
|---|---|---|---|
| Operative cure by IOPTH, (n, %) | 275 (98.9%) | 1912 (98.0%) | 0.355 |
| Follow up | |||
| All, months (median, IQI) | 8 (2, 44) | 6 (2, 44) | 0.065 |
| If ≥ 6mo, months (median, IQI) | 32 (11,63) | 34 (10, 68) | 0.927 |
| PTH at ≥ 6 months, pg/ml (median, IQI) | 58 (37, 89) | 44 (32, 66) | <0.001 |
| Calcium at ≥ 6 months, mg/dl (median, IQI) | 9.4 (9.1, 9.8) | 9.5 (9.2, 9.8) | 0.577 |
| Cure by eucalcemia, (n, %) | 113 (98.3%) | 582 (97.0%) | 0.756 |
IQI – Interquartile interval
Statistically significant results are given in bold
Predictors of Parathyroid Gland Size
Given the finding that parathyroid gland size and weight differed significantly between groups, we sought to evaluate whether clinically known preoperative factors could predict gland size. Univariate linear regression modeling was performed to determine the association between clinical covariates and parathyroid gland size and weight on surgical pathology (Table 5). On univariate analysis, African-American race, female gender, higher preoperative serum calcium level, higher preoperative PTH level, higher preoperative urine calcium level, and lower patient income were associated with larger parathyroid glands by weight and size. In the final multivariate model for gland weight, African-American race remained significantly associated with higher gland weight after controlling for preoperative serum calcium and PTH levels (p=0.030). In the multivariate model for gland size, after controlling for higher preoperative serum calcium and PTH level, African-American race (p<0.001) and lower median income (p=0.032) both remained significantly associated with larger parathyroid gland size (Table 6).
Table 5.
Linear regression for covariates associated with weight of dominant abnormal gland
| Univariate | Multivariate | |||||
|---|---|---|---|---|---|---|
| Characteristics | Coefficient | p-value | 95% CI | Coefficient | p-value | 95% CI |
| Age | −0.4 | 0.857 | (−5.0, 4.2) | - | - | - |
| Female gender | −140 | 0.053 | (−281, 2) | - | - | - |
| African American Race | 314 | 0.001 | (136, 493) | 195 | 0.030 | (19, 372) |
| Medicare | 45 | 0.524 | (−94, 185) | - | - | - |
| Elixhauser score | −8 | 0.719 | (−49, 34) | |||
| Preoperative calcium (mg/dl) | 504 | 0.000 | (426, 582) | 425 | 0.000 | (340, 510) |
| Preoperative PTH (pg/ml) | 2.2 | 0.000 | (1.8, 2.6) | 2.0 | 0.000 | (1.6, 2.4) |
| Preoperative 24-hour urine calcium (mg) | 0.8 | 0.000 | (0.3, 1.2) | - | - | - |
| Median income (1,000 USD) | −3.9 | 0.001 | (−6.2, −1.5) | - | - | - |
| Below median | 141 | 0.020 | (22, 259) | - | - | - |
Table 6.
Linear regression for covariates associated with size of dominant abnormal gland
| Univariate | Multivariate | |||||
|---|---|---|---|---|---|---|
| Characteristics | Coefficient | p-value | 95% CI | Coefficient | p-value | 95% CI |
| Age | 0.0002 | 0.875 | (−0.002, 0.003) | - | - | - |
| Female gender | −0.08 | 0.043 | (−0.155, −0.002) | - | - | - |
| African American Race | 0.3 | 0.000 | (0.2, 0.4) | 0.19 | 0.000 | (0.09, 0.29) |
| Medicare | −0.005 | 0.894 | (−0.08, 0.07) | - | - | - |
| Elixhauser score | 0.01 | 0.189 | (−0.007, 0.037) | |||
| Preoperative calcium (mg/dl) | 0.3 | 0.000 | (0.2, 0.3) | 0.23 | 0.000 | (0.19, 0.28) |
| Preoperative PTH (pg/ml) | 0.001 | 0.000 | (0.0008, 0.0012) | 0.0009 | 0.000 | (0.0007, 0.0011) |
| Preoperative 24-hour urine calcium (mg) | 0.0005 | 0.000 | (0.0003, 0.0008) | - | - | - |
| Median income (1,000 USD) | −0.003 | 0.000 | (−0.004, −0.002) | −0.0014 | 0.032 | (−0.0027, −0.0001) |
| Below median | 0.1 | 0.000 | (0.06, 0.19) | - | - | - |
Discussion
The current study examined the association between race and clinical presentation in patients presenting for parathyroidectomy for primary hyperparathyroidism. Our data suggest that at the time of surgical referral, African-American patients have more biochemically severe disease and higher rates of incomplete evaluation compared to White patients. There were no differences in rates of single adenoma, double adenoma, or multigland parathyroid hyperplasia between groups. On surgical pathology, African-American patients had glands that were more than 10% larger by size and almost 60% larger by weight compared to White patients, suggestive of more advanced disease. Even after controlling for parathyroid hormone and calcium levels which are well-established predictors of parathyroid gland size, African-American race was associated with larger parathyroid adenomas [22-24]. African-American patients were less likely to have known BMD loss, but they were significantly less likely to have received a DXA scan preoperatively. Despite the differences in presentation and operative findings, operative success and cure rates were the same regardless of race.
We hypothesize that the findings of more biochemically severe disease and higher rates of incomplete evaluation are linked and furthermore are related to delays in treatment in the African-American population. An extensive literature exists on delay in diagnosis, treatment and disease severity as it relates to race. This has been demonstrated both in malignant disease, where African-American women disproportionately experience delays in diagnosis and treatment of breast carcinoma and African-Americans are more likely to have more advanced stage colorectal cancer at diagnosis, and in benign disease, where our group has demonstrated that African-American patients experience longer times to surgical referral of benign thyroid disease [25-27]. Our group has also previously shown that African-American patients have more severe thyroid disease, with larger glands, and higher rates of compressive symptoms and dysphagia [28]. Significant treatment delays have been well-documented in PHPT where time to surgery is approximately four years, according to recent literature [29]. An extended delay in diagnosis or surgical referral could plausibly explain the observed higher biochemical severity of PHPT in African-Americans. It is challenging to determine the complex interplay between race and socioeconomic status in health outcomes. Lower socioeconomic status has been previously associated with lower likelihood of undergoing surgical treatment for PHPT [30]. In the current study, we found that race was independently predictive of larger parathyroid gland size, even after controlling for lower median income. Interestingly, in our study cohort, African-American patients had slightly higher rates of commercial insurance despite lower median income compared to White patients. These data must be interpreted with caution however, as our surgical cohort is inherently biased toward insured patients, given the elective nature of most parathyroidectomies performed for primary hyperparathyroidism.
As an alternative hypothesis, more severe disease might be due to underlying differences in physiology, and an incomplete evaluation might be the result of earlier surgical referral in the setting of biochemically more severe disease. However, the current study was not designed to assess time to diagnosis or reason for referral, and therefore cannot discriminate regarding diagnostic or referral delays. Further prospective research on time to diagnosis and referral is needed.
As a retrospective study, this analysis is inherently limited. However, all data was prospectively collected, mitigating potential recall bias. The study was limited to patients referred for surgery, and therefore does not capture events contributing to diagnosis and referral. In addition, while this study primarily analyzed differences by race, it is important to note the impact of other socioeconomic factors and social determinants of health on disease outcomes [15, 30-32]. To address this, we utilized income data as a surrogate for socioeconomic factors. However, data was incorporated at zip code level, and was therefore not patient-specific data. Additionally, long-term follow-up data was available for only approximately one-third of patients which may bias final cure rates, although we did not observe a difference in rates of long-term follow-up by race.
In conclusion, the current research found significant differences in severity of disease, completeness of preoperative evaluation, and size of parathyroid glands between African-American and White parathyroidectomy patients. Although it is disheartening that even in a racially heterogeneous tertiary care center, we find persistent disparities in the degree of biochemical disease severity and completeness of workup prior to surgical referral, it is encouraging that surgical success and cure rates did not differ between African-American and White patients. Our findings suggest that African-American patients may benefit from earlier surgical referral. Further research is needed to understand the etiology and clinical impact of racial disparities in patients with primary hyperparathyroidism and may identify potential targets for system-based interventions.
Acknowledgments
Grant Support: Support for HW from the National Center for Advancing Translational Sciences of the National Institutes of Health, Award Number KL2-TR001879.
Footnotes
Publisher's Disclaimer: This Author Accepted Manuscript is a PDF file of an unedited peer-reviewed manuscript that has been accepted for publication but has not been copyedited or corrected. The official version of record that is published in the journal is kept up to date and so may therefore differ from this version.
Disclosures: The authors (JF, KG, RRK, JPE, CW, DLF, and HW) have no disclosures.
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