Socioeconomic disparity in the association between fine particulate matter exposure and papillary thyroid cancer.

BACKGROUND: Limited data exists suggesting that cumulative exposure to air pollution in the form of fine particulate matter (aerodynamic diameter ≤ 2.5 µm [PM2.5]) may be associated with papillary thyroid carcinoma (PTC), although this relationship has not been widely established. This study aims to evaluate the association between PM2.5 and PTC and determine the subgroups of patients who are at the highest risk of PTC diagnosis. METHODS: Under IRB approval, we conducted a case-control study of adult patients (age ≥ 18) newly diagnosed with PTC between 1/2013-12/2016 across a single health care system were identified using electronic medical records. These patients were compared to a control group of patients without any evidence of thyroid disease. Cumulative PM2.5 exposure was calculated for each patient using a deep learning neural networks model, which incorporated meteorological and satellite-based measurements at the patients' residential zip code. Adjusted multivariate logistic regression was used to quantify the association between cumulative PM2.5 exposure and PTC diagnosis. We tested whether this association differed by gender, race, BMI, smoking history, current alcohol use, and median household income. RESULTS: A cohort of 1990 patients with PTC and a control group of 6919 patients without thyroid disease were identified. Compared to the control group, patients with PTC were more likely to be older (51.2 vs. 48.8 years), female (75.5% vs 46.8%), White (75.2% vs. 61.6%), and never smokers (71.1% vs. 58.4%) (p < 0.001). After adjusting for age, sex, race, BMI, current alcohol use, median household income, current smoking status, hypertension, diabetes, COPD, and asthma, 3-year cumulative PM2.5 exposure was associated with a 1.41-fold increased odds of PTC diagnosis (95%CI: 1.23-1.62). This association varied by median household income (p-interaction =0.03). Compared to those with a median annual household income <$50,000, patients with a median annual household income between $50,000 and < $100,000 had a 43% increased risk of PTC diagnosis (aOR = 1.43, 95%CI: 1.19-1.72), and patients with median household income ≥$100,000 had a 77% increased risk of PTC diagnosis (aOR = 1.77, 95%CI: 1.37-2.29). CONCLUSIONS: Cumulative exposure to PM2.5 over 3 years was significantly associated with the diagnosis of PTC. This association was most pronounced in those with a high median household income, suggesting a difference in access to care among socioeconomic groups.

Association between Pre-Kidney Transplant Elevated Parathyroid Hormone and Post-Transplant Graft Loss.

BACKGROUND: Prior to kidney transplantation (KT) most patients have an elevated parathyroid hormone (PTH). However, the impact of PTH on post-KT mortality and graft loss is unclear. We quantified the association between PTH levels measured at transplant and adverse post-KT outcomes. STUDY DESIGN: A prospective longitudinal cohort of 1,136 KT recipients from a single tertiary care center between 12/2008 and 2/2020. Pre-KT PTH levels were abstracted retrospectively. Adjusted multivariable Cox proportional hazards models were used to estimate the association between pre-KT PTH levels and mortality and death-censored graft loss (DCGL). RESULTS: Of 1,136 recipients, pre-KT PTH levels were ≤300pg/mL in 62.3% and >600pg/mL in 12.5%. Compared to those with a pre-KT PTH≤300pg/mL, patients with a pre-KT PTH>600pg/mL were more likely to be Black (51.4% vs. 34.6%) and have a longer dialysis vintage (4.8y vs. 1.7y) (p<0.001). Those with a pre-KT PTH>600pg/mL had a higher 10-year cumulative incidence of DCGL than those with PTH≤300pg/mL (31.7% vs. 15.4%, p<0.001). After adjusting for confounders, pre-KT PTH>600pg/mL was associated with a 1.76-fold increased risk of DCGL (95% CI: 1.16-2.65). The magnitude of this association differed by race (pinteraction=0.011) and by treatment (pinteraction=0.018). Among non-Black patients, a PTH>600pg/mL was associated with a 3.21-fold increased risk of DCGL compared to those with PTH≤300pg/mL (95%CI: 1.77-5.81). Among untreated patients, those with PTH>600pg/mL had a 2.54-fold increase in DCGL (95%CI: 1.44-4.47). There was no association between pre-KT PTH and mortality risk. CONCLUSIONS: PTH >600pg/mL prior to KT increased the risk of DCGL by 76%, demonstrating the importance of treating PTH prior to KT to prevent graft loss in a contemporary era with the introduction and widespread availability of medical therapy.

Prevalence and risk factors for dysphagia in older adults after thyroid and parathyroid surgery.

BACKGROUND: We aimed to determine the prevalence and risk factors for dysphagia in adults 65 years and older before and after thyroidectomy or parathyroidectomy. METHODS: We performed a longitudinal prospective cohort study of older adults undergoing initial thyroidectomy or parathyroidectomy. We administered the Dysphagia Handicap Index questionnaire preoperatively and 1, 3, and 6 months postoperatively. We compared preoperative and postoperative total and domain-specific scores using paired t tests and identified risk factors for worse postoperative scores using multivariable logistic regression. RESULTS: Of the 175 patients evaluated, the mean age was 71.1 years (range = 65-94), 73.7% were female, 40.6% underwent thyroidectomy, 57% underwent bilateral procedures, and 21.1% had malignant diagnoses. Preoperative swallowing dysfunction was reported by 77.7%, with the prevalence 22.4% greater in frail than robust patients (P = .013). Compared to preoperative scores, 43.4% and 49.1% had worse scores at 3 and 6 months postoperatively. Mean functional domain scores increased by 62.3% at 3 months postoperatively (P = .007). Preoperative swallowing dysfunction was associated with a 3.07-fold increased likelihood of worse functional scores at 3 months. Whereas frailty was associated with preoperative dysphagia, there was no association between worse postoperative score and age, sex, race, frailty, body mass index, smoking status, gastroesophageal reflux disease, comorbidity index, malignancy, surgical extent, or type of surgery. CONCLUSION: Adults 65 years and older commonly report swallowing impairment preoperatively, which is associated with a 3.07-fold increased likelihood of worsened dysphagia after thyroid and parathyroid surgery that may persist up to 6 months postoperatively.

Secondary Hyperparathyroidism and Cognitive Decline.

Purpose of Review: Secondary hyperparathyroidism (SHPT) likely contributes to the high prevalence of cognitive decline found among individuals with end-stage kidney disease (ESKD). Our objective is to critically evaluate the recent literature regarding the association between SHPT and cognitive decline and identify potential mechanisms. Recent Findings: Nine studies assessing the relationship between SHPT and cognition have been published in the last two decades, each showing that elevated parathyroid hormone (PTH) levels were associated with cognitive decline. One also found structural changes within the brain related to SHPT. Additionally, two found that SHPT treatment decreases the risk of cognitive decline in ESKD patients. Summary: SHPT is associated with cognitive impairment. However, the severity of SHPT associated with these changes and the specific cognitive domains affected remain unclear. Future studies are needed to focus on specific cognitive domains, the trajectory of cognitive decline, and optimal treatment strategies including the impact of kidney transplant and tertiary hyperparathyroidism.

Black patients are more likely to undergo parathyroidectomy for secondary hyperparathyroidism.

BACKGROUND: Prior studies have demonstrated racial disparities in the severity of secondary hyperparathyroidism among dialysis patients. Our primary objective was to study the racial and socioeconomic differences in the timing and likelihood of parathyroidectomy in patients with secondary hyperparathyroidism. METHODS: We used the United States Renal Data System to identify 634,428 adult (age ≥18) patients who were on maintenance dialysis between 2006 and 2016 with Medicare as their primary payor. Adjusted multivariable Cox regression was performed to quantify the differences in parathyroidectomy by race. RESULTS: Of this cohort, 27.3% (173,267) were of Black race. Compared to 15.4% of White patients, 23.1% of Black patients lived in a neighborhood that was below a predefined poverty level (P < .001). The cumulative incidence of parathyroidectomy at 10 years after dialysis initiation was 8.8% among Black patients compared to 4.3% among White patients (P < .001). On univariable analysis, Black patients were more likely to undergo parathyroidectomy (adjusted hazard ratio = 1.83; 95% confidence interval, 1.74-1.93). This association persisted after adjusting for age, sex, cause of end-stage renal disease, body mass index, comorbidities, dialysis modality, and poverty level (adjusted hazard ratio = 1.35; 95% confidence interval, 1.27-1.43). Therefore, patient characteristics and socioeconomic status explained 26% of the association between race and likelihood of parathyroidectomy. CONCLUSION: Black patients with secondary hyperparathyroidism due to end-stage renal disease are more likely to undergo parathyroidectomy with shorter intervals between dialysis initiation and parathyroidectomy. This association is only partially explained by patient characteristics and socioeconomic factors.

Hyperparathyroidism at 1 year after kidney transplantation is associated with graft loss.

BACKGROUND: Hyperparathyroidism persists in many patients after kidney transplantation. The purpose of this study was to evaluate the association between post-transplant hyperparathyroidism and kidney transplantation outcomes. METHODS: We identified 824 participants from a prospective longitudinal cohort of adult patients who underwent kidney transplantation at a single institution between December 2008 and February 2020. Parathyroid hormone levels before and after kidney transplantation were abstracted from medical records. Post-transplant hyperparathyroidism was defined as parathyroid hormone level ≥70 pg/mL 1 year after kidney transplantation. Cox proportional hazards models were used to estimate the adjusted hazard ratios of mortality and death-censored graft loss by post-transplant hyperparathyroidism. Models were adjusted for age, sex, race/ethnicity, college education, parathyroid hormone level before kidney transplantation, cause of kidney failure, and years on dialysis before kidney transplantation. A Wald test for interactions was used to evaluate the risk of death-censored graft loss by age, sex, and race. RESULTS: Of 824 recipients, 60.9% had post-transplant hyperparathyroidism. Compared with non-hyperparathyroidism patients, those with post-transplant hyperparathyroidism were more likely to be Black (47.2% vs 32.6%), undergo dialysis before kidney transplantation (86.9% vs 76.6%), and have a parathyroid hormone level ≥300 pg/mL before kidney transplantation (26.8% vs 9.5%) (all P < .001). Patients with post-transplant hyperparathyroidism had a 1.6-fold higher risk of death-censored graft loss (adjusted hazard ratio = 1.60, 95% confidence interval: 1.02-2.49) compared with those without post-transplant hyperparathyroidism. This risk more than doubled in those with parathyroid hormone ≥300 pg/mL 1 year after kidney transplantation (adjusted hazard ratio = 4.19, 95% confidence interval: 1.95-9.03). The risk of death-censored graft loss did not differ by age, sex, or race (all Pinteraction > .05). There was no association between post-transplant hyperparathyroidism and mortality. CONCLUSION: The risk of graft loss was significantly higher among patients with post-transplant hyperparathyroidism when compared with patients without post-transplant hyperparathyroidism.

Impact of the 2015 American thyroid association guidelines on treatment in older adults with low-risk, differentiated thyroid cancer.

BACKGROUND: The impact of the 2015 ATA guidelines on treatment for differentiated thyroid cancer (DTC) in older adults is unclear. METHODS: 60,567 adults (age≥18) with low-risk DTC diagnosed between 2010 and 2018 were identified using SEER-21. Annual rates of total thyroidectomy (TT), hemithyroidectomy (HT), and active surveillance (AS) were analyzed using interrupted time series stratified by age: younger adults (18-64), older adults (65-79), and the super-elderly (≥80). RESULTS: After 2015, annual rates of TT decreased by 2.6% and 1.9% in younger and older adults (p < 0.001), but increased by 4.6% in the super-elderly (p = 0.0126). Annual rates of HT increased by 2.6% and 1.7% in younger and older adults (p < 0.001), but decreased by 3.8% in the super-elderly (p = 0.0029). Older adults and the super-elderly were more likely than younger adults to undergo HT (aOR = 1.1, 95% CI: 1.03-1.2, p = 0.002 and aOR = 1.5, 95% CI: 1.3-1.7, p < 0.001) and AS (aOR = 1.5, 95% CI: 1.4-1.7, p < 0.001 and aOR = 6.5, 95% CI: 5.4-7.7, p < 0.001) when compared to TT following 2015. CONCLUSIONS: Treatment of DTC continues to vary significantly among age groups.

Comparing surgical thoroughness and recurrence in thyroid cancer patients across race/ethnicity.

BACKGROUND: For patients with differentiated thyroid cancer who will receive postoperative radioactive iodine, thyroid remnant uptake can be calculated and may point to the thoroughness of the surgical resection. In the United States, outcome disparities exist among ethnic/racial minorities with differentiated thyroid cancer. Data about surgical thoroughness and recurrence rates across races/ethnicities do not exist. This study compared the amount of thyroid remnant uptake and cancer recurrence rates across race/ethnicity. METHODS: This was a retrospective analysis of adult patients with differentiated thyroid cancer who had postoperative radioactive iodine in 2017 and 2018 and were followed to 2020. We collected thyroid bed remnant uptake from postoperative radioactive iodine scans and analyzed it as a ratio of percent of uptake to dose of radioactive iodine received to control for varying radioactive iodine doses. Thyroid remnant, uptake to dose of radioactive iodine received, and recurrence were evaluated across race/ethnicity. RESULTS: Of 218 patients: 61% were White, 21% Black, 11% Asian, and 7% Hispanic; 72% were female. Seventy-one percent of patients had their surgery done by a high-volume surgeon, although volume data were not available for all. In White, Black, Asian, and Hispanic patients, median uptake was 0.68%, 0.44%, 1.5%, and 0.8%, respectively (P = .13). We did not observe differences in median uptake to dose of radioactive iodine received across groups (P = .41). Recurrence rate was 17.0% among White patients, 16.7% among Black patients, 17.6% among Asian patients, and 16.7% among Hispanic patients (P = 1.00). CONCLUSION: We did not observe differences across race/ethnicity in surgical thoroughness or rate of recurrence. These findings suggest that disparities may be mitigated when ethnic/racial minorities have similar access to quality surgical care.