Bancos, Irina

Abstract Context Diagnosing adrenal insufficiency (AI) often requires complex testing, which can be time-consuming and expensive. Dehydroepiandrosterone sulfate (DHEAS) is a promising marker of hypothalamic-pituitary-adrenal axis function; however, its diagnostic performance has not yet been evaluated in a large-scale study. Objective Evaluate the performance of DHEAS and baseline cortisol in assessing AI. Design Single-center retrospective cohort study. Setting Referral center. Patients Adults who underwent cosyntropin stimulation testing (CST) between 2005 and 2023 and had DHEAS measured within 3 months prior to CST. Main Outcome Measures Area under receiver operating characteristic curve (AUROC) for DHEAS and baseline cortisol. Prevalence of AI based on various DHEAS and baseline cortisol concentrations. Results Among 1135 patients, 195 (17.2%) had AI. Both baseline cortisol and DHEAS independently had good diagnostic performance with AUROC 0.81 [95% confidence interval (CI) 0.77-0.84 and 0.81 (95% CI 0.78-0.85)], respectively. Time of CST performance had no significant effect on diagnostic accuracy of baseline cortisol while recent glucocorticoid use decreased diagnostic performance of DHEAS (AUROC 0.72 vs 0.83). Only 1.2% of patients with baseline cortisol ≥10 mcg/dL had AI based on CST. Among patients with baseline cortisol between 5 and 9.9 mcg/dL, only 1.3% had AI if DHEAS was ≥60 mcg/dL. Conversely, the majority (72.2%) of patients with both baseline cortisol <5 mcg/dL and DHEAS <25 mcg/dL were found to have AI. Conclusion DHEAS has good diagnostic performance in assessing AI. Measuring both baseline cortisol and DHEAS concentrations may eliminate the need for further dynamic testing in many patients.

Abstract Objective To study pregnancy outcomes and complications in women with congenital adrenal hyperplasia (CAH). Methods A retrospective multicenter study was conducted at tertiary reference centers in 5 countries (Austria, Germany, Italy, Sweden, USA), including 72 adult women with CAH (nonclassic [NC] n = 34, simple virilizing [SV] n = 21, salt wasting [SW] n = 17). Results A total of 133 pregnancies, 112 live births, and 25 abortions were documented. Prolonged latency to pregnancy was observed (median 11 months in SW, 24 months in SV, 8 months in NC), with a notable use of fertility-enhancing medication (25.6%) and assisted reproductive techniques (30.8%). Over half of the women in each group took more than 12 months to conceive. The average number of live births (1.4-1.6 children per woman) was similar across CAH phenotypes and comparable to the general population. Spontaneous abortion rates (18.0%) were also similar across phenotypes. Primary cesarean section rates (60.9%) were higher than in the general population, though 23.8% of women with SV and 29.4% of women with SW gave birth naturally, despite most having undergone genital surgery. Children categorized as small for gestational age were 20.5%. Pregnancy, delivery, and postpartum complications were rare for mothers and neonates. Conclusion The study indicates a prolonged latency to pregnancy and high use of fertility treatments in CAH patients, regardless of phenotype. Abortion rates were not increased, and overall pregnancy and perinatal outcomes were favorable.

Background: Oncocytic adrenal neoplasms, defined by ≥90 % of oncocytic cells, are rare. The significance of oncocytic changes within an adrenal neoplasm remains unclear. Methods: A retrospective study of adults who underwent adrenalectomy at a large center identified pure oncocytic neoplasms on final pathology (1997-2022). Neoplasms were categorized based on Lin-Weiss-Bisceglia system as malignant, benign, or of uncertain malignant potential. Analysis was performed using Fisher exact, Kruskal-Wallis tests, and Kaplan-Meier analysis. Results: Among a total of 33 patients, 24% had benign, 36% malignant, and 39% neoplasm of uncertain malignant potential. None of the benign neoplasms recurred, while 50% of the malignant neoplasms recurred (median of 40 months). Two of 13 neoplasms initially thought to be of uncertain malignant potential recurred as distant metastatic adrenocortical carcinoma at 11 and 25 months, over a median follow-up duration of 31 months. Ki67% was available for 20 patients: median (IQR) Ki67% was 5 (1, 5) for benign, 10 (6, 15) for malignant, and 6.5 (5, 10) for neoplasms of uncertain behavior, P = 0.05. Recurred neoplasms had higher Ki67% at initial resection compared to cases that did not recur. Conclusion: While oncocytic adrenal neoplasms are rare, a significant proportion are malignant or have malignant potential. Judicious follow-up is required for oncocytic adrenal neoplasms of uncertain malignant potential, as they can recur as metastatic adrenocortical carcinoma. Ki67% should always be obtained in cases of malignancy or uncertain malignant potential as it can predict recurrence. Larger studies are needed to evaluate the appropriate follow-up protocols for these neoplasms.

BACKGROUND: Distinguishing between unilateral and bilateral primary aldosteronism, a major cause of secondary hypertension, is crucial due to different treatment approaches. While adrenal venous sampling is the gold standard, its invasiveness, limited availability, and often difficult interpretation pose challenges. This study explores the utility of circulating microRNAs (miRNAs) and machine learning in distinguishing between unilateral and bilateral forms of primary aldosteronism. METHODS: MiRNA profiling was conducted on plasma samples from 18 patients with primary aldosteronism taken during adrenal venous sampling on an Illumina MiSeq platform. Bioinformatics and machine learning identified 9 miRNAs for validation by reverse transcription real-time quantitative polymerase chain reaction. Validation was performed on a cohort consisting of 108 patients with known subdifferentiation. A 30-patient subset of the validation cohort involved both adrenal venous sampling and peripheral, the rest only peripheral samples. A neural network model was used for feature selection and comparison between adrenal venous sampling and peripheral samples, while a deep-learning model was used for classification. RESULTS: Our model identified 10 miRNA combinations achieving >85% accuracy in distinguishing unilateral primary aldosteronism and bilateral adrenal hyperplasia on a 30-sample subset, while also confirming the suitability of peripheral samples for analysis. The best model, involving 6 miRNAs, achieved an area under curve of 87.1%. Deep learning resulted in 100% accuracy on the subset and 90.9% sensitivity and 81.8% specificity on all 108 samples, with an area under curve of 86.7%. CONCLUSIONS: Machine learning analysis of circulating miRNAs offers a minimally invasive alternative for primary aldosteronism lateralization. Early identification of bilateral adrenal hyperplasia could expedite treatment initiation without the need for further localization, benefiting both patients and health care providers.

Abstract Disclosure: J. Saini: None. B. Bahrani Fard: None. M. Suresh: None. R. Sandooja: None. Y. Hleibiehova: None. E. Atkinson: None. S. Achenbach: None. I. Bancos: None. Background: Patients with endogenous hypercortisolism experience glucocorticoid withdrawal syndrome (GWS) following curative surgery. The symptoms of GWS include fatigue, weakness, muscle aches, joint pain, mood changes, and sleep disturbance. Limited interventions have been explored to alleviate the symptoms of GWS and improve patients’ quality of life. The use of meditation as an intervention has been reported to enhance postsurgical recovery in patients with other conditions and offers a promising intervention for GWS. Objective: To determine the impact of a portable, wearable, electroencephalographic device (MUSE headband device) used for guided meditation practices on the quality of life of patients in the first 12 weeks post-surgery for endogenous hypercortisolism. Methods: We conducted a single-center prospective longitudinal study of adults with endogenous hypercortisolism undergoing curative surgery between 2018 and 2024. The patients were enrolled before the surgical intervention and were followed for 2 years. Only patients who completed at least 4 weeks of follow-up were included. The study comprised of 2 groups; (1) The interventional group included consecutive patients who were offered a MUSE headband with instructions to meditate for at least 10 minutes per day for 3 months (MUSE cohort) and (2) the comparison group included age-, sex-, clinical score, hypercortisolism type, and BMI-matched 3:1 patients (Referent cohort). Quality of life and symptoms of GWS were assessed with AddiQoL and Short Form-36 (SF-36) surveys. Results: At least 4 weeks post-surgical follow-up was completed by 27 patients in the MUSE cohort and 81 referent subjects. Age (median 51 vs 47 years), women (82% vs 84%), BMI (median 31 vs 32 kg/m2), the subtype of hypercortisolism (pituitary 48% vs 52%), clinical (median 16 vs 15) and biochemical (median 6 vs 7) severity scores were similar between the two groups (P>0.05 for all). At baseline, AddiQoL score was similar in groups (median of 66 vs 70, P=0.083), though symptoms of fatigue (92.6% vs 69.1%, P=0.015) and lightheadedness (37% vs 17.3%, P=0.033) were more frequent in MUSE cohort. After 12 weeks, 20 patients using MUSE demonstrated improvement compared to 67 no muse patients in the SF-36 physical component (mean delta 3.9 (SD 11.77) vs -2.19 (SD 9.67), P=0.010). The physical functioning SF-36 subcomponent (4.94 (8.77) vs 0.92 (9.24), P=0.048) and body pain SF-36 subcomponent (2.69 (11.89) vs -3.69 (8.32), P=0.008) domains improved in the MUSE intervention group, when compared to referent cohort. No significant improvement in SF-36 mental component scores was seen in both groups. Conclusions: The use of wearable electroencephalographic device for meditation was associated with improvement in the quality of life of patients recovering from hypercortisolism, particularly in the domains of body pain and physical functioning. Presentation: 6/3/2024

Abstract Disclosure: J. Saini: None. R. Nathani: None. J. Larson: None. V. Fell: None. I. Bancos: None. Background: Surgical menopause due to bilateral salpingo-oophorectomy (BSO) at a younger age is associated with an increased risk of cardiovascular disease, cognitive decline, and increased mortality. Aging is associated with abnormalities in steroid metabolome, most notably an increased glucocorticoid to androgen ratio (“adrenal aging”). We hypothesized that in postmenopausal women of the same age, the duration of menopause is associated with adrenal aging. Objective: To determine the differences in the adrenal steroid metabolome of women with a history of BSO as compared to age-matched women following natural menopause. Methods: We conducted a single-center cross-sectional study in postmenopausal women with or without a history of BSO, between December 2020 to December 2022 Each participant collected 24-hour urine, which was analyzed for steroid profiling by liquid chromatography-tandem mass spectrometry (25 steroids). Exclusion criteria were inability to collect a 24h urine sample, exogenous glucocorticoid use, advanced malignancy, and chronic opioid use. Primary endpoints were glucocorticoid/androgen ratio, 11β-hydroxysteroid dehydrogenase type 2 activity (cortisol/cortisone, Tetrahydrocortisol (THF) + 5 α-tetrahydrocortisol (5 α-THF)/ Tetrahydrocortisone, THE) and 5 α-reductase type activity (Tetrahydrocortisol (THF)/5 α-tetrahydrocortisol (5 α-THF) and Etiocholanolone/Androsterone, Et/An). Results: A total of 245 women were enrolled: 124 women (median age of 66 years, IQR 63-72) with a history of BSO and 121 women (median age of 68 years, IQR 64-71) who underwent natural menopause (P=0.214). Median age at menopause was 44 years (IQR 41-46) in the BSO group, and 50 years (IQR 48-53) in the natural menopause group. History of hormone replacement therapy with estrogen was reported in 161 (66%) women, more frequently (92% vs 39%, P<0.001) and for a longer duration (median 12 years (IQR 6-16) vs 6 years (IQR 3-9), P<0.001) in in the BSO group, as compared to the natural menopause group. Although both groups had similar levels of urinary androgens (median 1387 vs 1686 mcg/24h, P=0.063) and total glucocorticoids (median 10877 vs 10277 mcg/24h, P=0.354), women with a history of BSO demonstrated a higher glucocorticoid/androgen ratio (median 7.9 (IQR 5.0-11.1) vs 6.7 (4.3-9.9), P=0.014), and a lower Et/An ratio (median 1.4 vs 1.6, P=0.045), but not THF/5aTHF ratio (median 1.7 vs 1.8, P=0.380) in comparison to women with natural menopause. No differences were found in other ratios. Conclusion: Women with a history of BSO demonstrated a higher glucocorticoid/androgen ratio in comparison to women undergoing natural menopause, suggestive of BSO-induced accelerated “adrenal aging”. Future studies need to examine associations between the abnormal steroid metabolome and increased cardiovascular morbidity, frailty, and mortality reported following BSO. Presentation: 6/3/2024

Abstract Disclosure: R.J. Auchus: Consulting Fee; Self; Neurocrine Biosciences, Inc., Crinetics Pharmaceuticals, OMass Therapeutics, H Lundbeck A/S, Adrenas Therapeutics. Research Investigator; Self; Neurocrine Biosciences, Inc., Diurnal, Crinetics Pharmaceuticals, Spruce Biosciences. O. Hamidi: Advisory Board Member; Self; Corcept Therapeutics, Recordati Rare Diseases, Amryt Pharma, Neurocrine Biosciences, Inc., Xeris, Lantheus. R. Pivonello: Advisory Board Member; Self; Corcept Therapeutics, Recordati AG, Crinetics Pharmaceuticals, H. Lundbeck A/S. Research Investigator; Self; Corcept Therapeutics, Recordati AG, Strongbridge Biopharma, Neurocrine Biosciences, Inc. I. Bancos: Consulting Fee; Self; Corcept Therapeutics, Recordati Rare Diseases, HRA Pharmaceuticals, Neurocrine Biosciences, Inc., Diurnal, Spruce Biosciences, Sparrow Pharmaceuticals, Adrenas Therapeutics. Research Investigator; Self; Recordati Rare Diseases. G. Russo: Advisory Board Member; Self; Novartis Pharmaceuticals, Sandoz, Diurnal. Speaker; Self; Novartis Pharmaceuticals, Sandoz, Diurnal. S.F. Witchel: Research Investigator; Self; Neurocrine Biosciences, Inc. A.M. Isidori: Research Investigator; Self; Pfizer, Inc., Merck Serono, HRA Pharmaceuticals, Recordati AG, Corcept. P. Rodien: Consulting Fee; Self; Pfizer, Inc., Novo Nordisk, Lilly USA, LLC, Ipsen, HRA Pharmaceuticals, IBSA Pharma, Recordati Rare Diseases. U. Srirangalingam: Advisory Board Member; Self; Diurnal. Speaker; Self; Diurnal. F.W. Kiefer: Advisory Board Member; Self; AstraZeneca, Boehringer Ingelheim, Eli Lilly & Company, Novartis Pharmaceuticals, Novo Nordisk, Pfizer, Inc., Sanofi. Speaker; Self; AstraZeneca, Boehringer Ingelheim, Eli Lilly & Company, Novartis Pharmaceuticals, Novo Nordisk, Pfizer, Inc., Sanofi. H. Falhammar: Consulting Fee; Self; Diurnal, Roche Diagnostics, Neurocrine Biosciences, Inc., H Lundbeck A/S, Adrenas Therapeutics. D.P. Merke: Research Investigator; Self; Diurnal, Adrenas Therapeutics, Neurocrine Biosciences, Inc. N. Reisch: Consulting Fee; Self; Diurnal, Crinetics Pharmaceuticals, Neurocrine Biosciences, Inc., Spruce Biosciences, H Lundbeck A/S. J. Sturgeon: Employee; Self; Neurocrine Biosciences, Inc. E. Roberts: Employee; Self; Neurocrine Biosciences, Inc. V.H. Lin: Employee; Self; Neurocrine Biosciences, Inc. J.L. Chan: Employee; Self; Neurocrine Biosciences, Inc. R. Farber: Employee; Self; Neurocrine Biosciences, Inc.. Introduction: Classic congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21OHD), a genetic disorder characterized by cortisol deficiency and excess adrenal androgens, typically requires management with supraphysiological glucocorticoid (GC) doses. Crinecerfont is a novel oral CRF1 antagonist that reduced elevated adrenocorticotropic hormone and adrenal androgens in patients with 21OHD in 14-day open-label Phase 2 studies. This Phase 3 study (CAHtalyst: NCT04490915) evaluated whether crinecerfont can reduce daily GC dose while maintaining androgen control in adults with 21OHD. Methods: Adults (≥18 years) with 21OHD, stable GC regimens at doses >13 mg/m2/d in hydrocortisone equivalents (HCe), and normal or elevated androstenedione (A4) were randomized (2:1) to crinecerfont 100 mg BID or placebo for 24 weeks. GC dosing was maintained stable for 4 weeks, followed by a planned GC down-titration over 8 weeks to achieve a GC dose of 8-10 mg/m2/d. GC doses were adjusted as needed during the last 12 weeks to maintain A4 control (≤120% of baseline or ≤upper limit of normal [ULN]) by week 24. Results: In the 182 randomized participants (51% male, mean age 31 years), demographics and baseline characteristics were similar between treatment arms (122 crinecerfont, 60 placebo). Mean GC dose at baseline was 17.6 mg/m2/d HCe (32 mg/d), with 58% on HC alone, 29% taking predniso[lo]ne, and 13% taking dexamethasone; mean pre-GC A4 (620 ng/dL) was elevated >2-3-fold the ULN. Over 95% of participants completed the double-blind treatment period. At week 24, the crinecerfont arm had a significantly greater percent reduction in GC dose while maintaining A4 control vs placebo (-27% vs -10%; least squares mean difference [LSMD]: -17%; p<0.0001) (primary endpoint). At week 4 (end of GC-stable period), a greater reduction in A4 prior to the morning GC dose was observed with crinecerfont vs placebo (LSMD: -345 ng/dL; p<0.0001) (key secondary endpoint). At week 24, a higher percentage of participants reached a protocol-defined physiological GC dose (≤11 mg/m2/d) while maintaining A4 control with crinecerfont (63% vs 18% for placebo; p<0.0001) (key secondary endpoint). The most common treatment-emergent adverse events (AEs) in the crinecerfont arm were fatigue (25% vs 15% for placebo), headache (16% vs 15%), and COVID-19 (14% vs 9%). There were few serious AEs (3% overall), with none assessed as related to the study drug. Conclusions: Crinecerfont, an oral CRF1 antagonist, represents a novel treatment option to improve androgen control for patients with 21OHD. In the largest interventional Phase 3 study conducted to date in adults with 21OHD, crinecerfont led to a significant reduction in A4 while GC dose was stable, enabling a significant percent reduction in GC dose while maintaining A4 control at 24 weeks. Crinecerfont was overall well tolerated. Presentation: 6/1/2024

Abstract Disclosure: O. Hamidi: Advisory Board Member; Self; Corcept, Neurocrine Biosciences, Amryt Pharma, Recordati Rare Diseases, Lantheus, Xeris. B.H. Salama: None. P. Dogra: None. A.P. Dackiw: None. F. Nwariaku: None. A. Islam: None. A. Mehta: None. S.C. Oltmann: None. S. Mirfakhraee: None. T. McKenzie: None. T.R. Foster: None. M. Lyden: None. B.M. Dy: None. I. Bancos: None. Introduction: Patients with mild autonomous cortisol secretion (MACS) are at risk for adrenal insufficiency (AI) after unilateral adrenalectomy. We aimed to determine the prevalence, predictors, and duration of AI after unilateral adrenalectomy for MACS, and to compare baseline and peak cortisol post cosyntropin stimulation test (CST) in diagnosing AI. Methods: We conducted a dual-center retrospective cohort study of patients with MACS who underwent unilateral adrenalectomy and were evaluated with postoperative cosyntropin stimulation test (CST). AI was diagnosed when postoperative morning cortisol was <10μg/dL and/or CST peak cortisol was <18μg/dL. Baseline and CST peak cortisol levels were considered concordant when both met corresponding cut-offs. Biochemical (BSS) and clinical (CSS) severity scores for hypercortisolism were calculated. Results: In 100 adults with MACS (77% women, median age 56 years, interquartile range [IQR] 48-63), median adenoma size was 2.8 cm (IQR, 2.2-3.7), and 25 (25%) had bilateral nodules. Median BSS was 3 (IQR, 2-5) and median CSS was 4 (IQR, 2-8). After adrenalectomy, AI was diagnosed in 56 (56%) patients. AI was associated with higher BSS, larger tumor size, but not age, sex, BMI, tumor laterality. Baseline and CST peak cortisol levels were concordant in 76% of cases. In 14% of cases morning cortisol was <10μg/dL but CST peak cortisol was ≥18μg/dL, and in 10% of cases morning cortisol was ≥10μg/dL, but CST peak cortisol was <18μg/dL. On a multivariable analysis that included age, sex, BMI, BSS, laterality, and tumor size, only higher BSS (odd ratio [OR] = 1.6 per 1 point) was associated with postoperative baseline cortisol <10μg/dL (P<0.05 for all). Independent predictors of CST peak cortisol <18μg/dL were BSS (OR 1.5 per 1 point) and unilateral adenoma (OR 3.7). During a median postoperative follow up of 13 months, 33 (59%) patients recovered from AI. Median time to recovery was 6.0 months, with AI recovery in 28% of patients by 2 months, 42% by 3 months, 53% by 6 months, and 64% by 12 months. Conclusions: Prevalence of postoperative AI in MACS was 56%. Only 76% of patients had concordant baseline and CST peak cortisol, with peak CST cortisol being more commonly abnormal in patients treated for unilateral MACS. Patients with larger adenomas and higher BSS were at higher risk for AI. Patients with MACS should be counseled about the risk and duration of AI after adrenalectomy. Presentation: 6/3/2024

Abstract Disclosure: C.A. Villavicencio Torres: None. I. Bancos: None. Background: Adrenocortical carcinoma (ACC) is a rare malignancy with an estimated annual incidence of 0.7-2 cases per million per year. Scarce data are available on rare histological variants of ACC. Objective: To describe the clinical presentation and outcomes of patients diagnosed with oncocytic, sarcomatoid and myxoid ACC variants. Methods: Retrospective single center cohort study, 1992-2021 of patients with rare histological ACC variant. Results: A total of 20 patients were diagnosed with oncocytic (17, 85%), sarcomatoid (2, 10%), or myxoid (1, 5%) ACC. Median age of diagnosis was 47 years (range 17-80), and 14 (70%) were women. All patients had unilateral ACC (12, 60% left) with a median tumor size of 11 cm (range 4-29). Adrenal hormone excess was documented in 10 (50%) patients, mostly with either glucocorticoid or androgen excess. ENSAT stage I, II, III, and IV was documented in 2 (10%), 10 (50%), 6 (30%), and 2 (10%) patients, respectively. All patients were treated with adrenalectomy (laparoscopic in 5 and open in 15). In addition, patients were treated with mitotane (10, 50%), radiation (7, 35%), and chemotherapy (5,25%). Mitotane was administered for a median of 12 months (range 4-31) and was discontinued mainly due to side effects in 9 (90%) patients. Patients were followed for a median follow up of 6.5 years (range 0.4-12). In addition to 2 patients who presented with ENSAT stage IV metastatic disease, metastatic disease developed in additional 6 (30%) patients who initially presented with localized ACC (3 stage 2, 3 stage 3, 5 oncocytic, 1 sarcomatoid). Metastatic sites included lung (n=2), omentum (n=1), duodenum (n=1), liver (n=4), and bones (n=1). At the end of follow up, 11 (55%) patients remained disease free (53% oncocytic, 50% sarcomatoid, 100% myxoid), 5 (25%) patients were alive with metastatic ACC (23% oncocytic, 50% sarcomatoid), and 4 patients died of ACC (median time to death 21 months (range 10-50) post-adrenalectomy). Conclusions: Patients with oncocytic, sarcomatoid, and myxoid ACC may have a better prognosis than in reported literature. Larger multicenter studies are needed to identify patient and tumor-specific factors that guide management to assure improved outcomes in these very rare patients. Presentation: 6/2/2024

Abstract Disclosure: A.J. Han: None. S.J. Achenbach: None. B.J. Atkinson: None. I. Bancos: None. Background: Diagnosis of adrenal insufficiency (AI) is often delayed due to its vague and non-specific symptomatology. As classic symptoms of AI such as fatigue and nausea are prevalent in the general population, identifying clinical features that are more specific to AI may help clinicians determine which patients require additional testing. Methods: A single-center retrospective study was performed of patients who underwent outpatient Cosyntropin stimulation testing (CST) between 2005-2018. Patients with oral glucocorticoid or estrogen use within 2 months of CST, and patients without available Current Visit Information (CVI) form at the time of CST were excluded. Presence of symptoms was obtained from CVI, and laboratory findings were electronically extracted. Adrenal insufficiency was defined as post-CST peak cortisol <18 mcg/dL. Morbidity was assessed using the Elixhauser index. Variables for multivariable analysis were defined a priori and included fatigue, dizziness, muscle pain, joint pain, weight loss >10 pounds, abdominal pain, nausea/vomiting, and hyponatremia. Results: Among 5347 patients who underwent CST, 376 (7.0%) of patients were found to have AI. There were no sex differences between patients with and without AI, however patients with AI were slightly older (median age 48.9 vs 47.1 years, p=0.026), and had a higher median BMI (26.5 vs 25.6 kg/m2, p=0.002). Prevalence of comorbidities was similar between the two groups, with a median Elixhauser index of 1 (IQR 1-3), however, patients with AI were more likely to report difficulties with activities of daily living (69% vs 57%, p<0.001). Hyponatremia was diagnosed in 4% of patients with AI and 3% of those without AI, p=0.208. Although patients in our cohort reported a high prevalence of fatigue (79%), dizziness (50%), joint pain (50%), muscle pain (48%), nausea (40%), abdominal pain (39%), and weight loss in the past 6 months (29%), there were no statistically significant differences in reported symptoms between patients with and without AI with the exception of joint pain (59% vs 49%, p<0.001) and muscle pain (54% vs 47%, p=0.009). Based on multivariable analysis, only joint pain (OR 1.51, 95% CI 1.14-1.99) and weight loss >10 pounds in the past 6 months (OR 1.31, 95% CI 1.02-1.68) were associated with higher odds of AI diagnosis. Interestingly, patients who reported fatigue had lower odds of AI diagnosis on CST (OR 0.66, 95% CI 0.49-0.88). Conclusions: Commonly associated symptoms of AI such as fatigue, dizziness, nausea, and abdominal pain were poor predictors of AI diagnosis based on CST. Consequently, the presence of these symptoms alone may not warrant additional testing. Notably, clinical features such as myalgia, arthralgia, and weight loss >10 pounds in the past 6 months were found to be more predictive of AI. Presentation: 6/1/2024