United States

Background 
Type 1 diabetes (T1D) is an autoimmune condition that affects 1 in 400 U.S. kids and teens, causing their bodies to no longer produce insulin and requiring lifelong insulin replacement therapy with injections or pumps to manage their blood sugar. Omnipod5 launched in 2022 as the first tubeless automated insulin delivery system. This pump integrates with the Dexcom G7 continuous glucose monitor and can be managed via a smartphone to adjust insulin delivery and manage glucose levels automatically. While Omnipod 5 has significantly improved glucose control, there are only modest A1c improvements for many patients. Our goal was to understand the drivers of glucose control based on measurable clinical, behavioral, or technological data. We investigated the relationship between insulin settings, patient behavior, and pump performance to identify the factors that influence time in range (TIR) (70-180 mg/dL). 
Methods 
All patients with T1D using the Omnipod 5 system at the Baylor College of Medicine pediatric endocrinology clinic in San Antonio were considered for this IRB-approved quality-improvement study. Approximately 400 patients were evaluated, and 59 were selected for inclusion in the 
study (22 males, 37 females, ages 4 to 19.4 years, mean 11.2 years). No specific exclusion criteria were applied. Data were obtained from the Glooko data management system. A multiple linear regression model was run with carb entries per day (1 to 6.8, mean 3) and percent time in automated mode (10% to 100%, mean 83%) against percent time in range (16% to 92%, mean 52%). 
Results 
For each additional carb entry per day, the TIR increases by 4.06% (p = 0.00094). For each additional 1% of time spent in automated mode, the TIR increases by 0.37% (p = 6.29e-06). Similarly, a 10% increase in time spent in automated mode is roughly equivalent to the impact of an additional carb entry (3.7% vs 4.06%). Both predictors are statistically significant and are positively associated with the TIR. The R-squared value was 0.5244. 
Conclusion 
Patients using Omnipod 5 may increase TIR and ultimately lower their blood glucose readings by increasing the amount of time in automated mode and increasing the number of carb entries per day, which justifies future interventional studies.

2025 AMA Research Challenge – Member Premier Access

Improving Outcomes in Pediatric Type 1 Diabetes with Omnipod 5

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Abstract Title: Safety and Efficacy of CB1 Receptor Antagonists for Weight Reduction: A Meta-Analysis

Background: Obesity is a major public health issue that is linked to a variety of comorbidities and increasing healthcare costs. Several pharmacological agents, including cannabinoid type 1 (CB1) receptor antagonists, have been studied for weight management. CB1 receptor antagonists target the endocannabinoid system, which regulate appetite and metabolism, offering potential benefits for weight reduction. However, concerns about psychiatric side effects have limited their clinical use. This meta-analysis aims to evaluate the efficacy and safety of CB1 receptor antagonists in overweight and obese adults to inform the development of safer and more effective therapies.

Methods: We searched PubMed, Embase, CENTRAL, ClinicalTrials.gov, and other sources for randomized controlled trials comparing CB1 receptor antagonists with placebo. Eligible trials enrolled adults with a BMI of 25 kg/m² or higher and reported changes in weight, BMI, waist circumference, fasting glucose, LDL cholesterol, or adverse events. Data were analyzed using RevMan version 5.4, and risk of bias was assessed using the Cochrane RoB 2 tool.

Results: Sixteen randomized controlled trials involving 13,882 participants were included. CB1 receptor antagonists had significantly reduced body weight compared to placebo (MD = −3.05 kg; 95% CI = −3.34 to −2.76; p<0.00001; I² = 17%), and subgroup analysis showed similar effects in short- and long-term follow-up. Waist circumference also had a significant reduction (MD = −2.79 cm; 95% CI = −3.15 to −2.43; p<0.00001; I² = 0%). There was a small but statistically significant decrease in fasting plasma glucose (MD = −0.14 mmol/L; 95% CI = −0.26 to −0.01; p=0.03; I² = 60%), while LDL cholesterol had no change (MD = 0.01 mmol/L; 95% CI = −0.04 to 0.06; p=0.79; I² = 0%). The intervention group experienced a small increase in total adverse events (RR = 1.04; 95% CI = 1.03 to 1.06; p<0.00001; I² = 0%) and a marked increase in psychiatric-related discontinuation (RR = 2.26; 95% CI = 1.69 to 3.03; p<0.00001; I² = 0%). Risk of bias assessment indicated that although some studies were at low risk across all domains, a subset had high risk due to missing outcome data and concerns related to the selection of reported results.

Conclusion: CB1 receptor antagonists demonstrate moderate effectiveness for weight reduction and improvements in waist circumference and glycemic control. However, their clinical utility is limited by dose-dependent psychiatric side effects. Future therapies targeting peripheral CB1 receptors may offer safer alternatives.

Safety and Efficacy of CB1 Receptor Antagonists for Weight Reduction: A Meta-Analysis

Background
Ewing’s Family of Tumors (EFT) involving the pancreas is exceedingly rare, accounting for only 0.3% of primary pancreatic neoplasms. Due to its nonspecific presentation and limited data, diagnosis and management remain challenging. This systematic review and survival analysis evaluates clinicopathological features, treatment approaches, survival outcomes, and prognostic factors in pancreatic EFT.

Methods
Following PRISMA guidelines, a systematic review (PROSPERO ID CRD42024585711) was conducted across Cochrane Library, Embase, PubMed, and Medline up to August 31, 2024. Case reports, series, and relevant abstracts were included if they provided individual patient data. Data on demographics, clinical features, tumor characteristics, treatment modalities, and survival outcomes were extracted and analyzed using descriptive statistics and Cox proportional-hazards models.

Results
Of 816 screened references, 67 studies (88 patients) were included. The median age was 23 years (IQR: 17-31, range: 2–78), with a slight male predominance (55.1%). The most common symptom was abdominal pain (68.8%). The pancreatic head was the most frequent tumor location (57.0%), with a median tumor size of 8.0 cm (range: 2.1-33.0). 11.4% were secondary tumors, and 22.6% were metastatic at diagnosis. 76.3% were treated with chemotherapy; 52.9% adjuvant and 25.5% neoadjuvant. Regimens used included VDC (Vincristine, doxorubicin, and cyclophosphamide) in 80.6%, IE (Ifosfamide and Etoposide) in 58.1%, and other agents in 19.4%. For local control, surgery (67.9%), radiation (5.1%), or a combination (14.1%) was used. On follow-up, 75.0% remained in remission, 17.6% metastasized, 8.8% recurred locally, and 5.9% progressed despite treatment. Survival outcomes were unavailable for 19 cases; mortality was 42.3% for the remaining, and 43.5% showed no evidence of disease. Patients were followed for a maximum of 120 months (median, 13.75 months). Univariate analysis of overall survival (OS) revealed a hazard ratio (HR) of 0.23 (p=0.02) for primary tumors, 0.36 (p=0.03) for surgically resected tumors without radiation, and 34.29 (p=0.04) for R1 resections. HR for disease-free survival (DFS) was 3.86 (p=0.03) for metastases, 3.38 (p=0.05) for necrotic tumors, and 5.76 (p=0.008) for operatively sampled positive lymph nodes. Age, tumor size, local invasion, and variations in chemotherapy did not produce statistically significant HR for OS or DFS.

Conclusion
Pancreatic ESFT is rare, mostly affecting patients under 30 with a slight male preponderance. The most common symptom is abdominal pain. Complete surgical resection is critical for survival, while necrosis, metastatic disease, and lymph node involvement confer poorer outcomes. Further research is needed to optimize therapeutic strategies.

Survival and Prognosis in Pancreatic Ewing’s Family of Tumors: A Systematic Review

Background: Current NCCN guidelines recommend right hemicolectomy (RHC) for appendiceal neuroendocrine tumors (aNETs) > 2.0 cm and observation for < 1.0 cm, but the management of tumors 1.0 – 2.0 cm remains controversial. Our goal was to compare long-term survival and recurrence for patients undergoing RHC versus appendectomy (APY) for 1.0 – 2.0 cm aNETs.

Methods: Patients with pathologically confirmed 1.0 – 2.0 cm aNETs treated at three Mayo Clinic sites from 1972-2024 were included. Primary outcomes were tumor recurrence and all-cause mortality post-resection. Associations with lymph node (LN) metastasis were calculated for patients with LN involvement.

Results: Sixty-five patients with 1.0 – 2.0 cm aNETs were identified, of whom 30 (46.2%) underwent APY alone, 34 (52.3%) underwent RHC, and one (1.5%) underwent ileocecectomy. The cohort was predominantly female (71%) and white (94%), with a median age at diagnosis of 39 years. Among patients with lymph nodes examined, the rate of nodal positivity for 1.0 – 2.0 cm tumors was 15.2%. Tumor size >1.5 cm vs ≤1.5 cm, T3/T4 stage, nor lymphovascular invasion were associated with node positivity. There was no significant difference in all-cause mortality between patients undergoing APY versus RHC. Node positivity was not associated with worse long-term survival. No recurrences were identified during a median follow up of 6.25 years (IQR 2.44 – 12.63).

Conclusion: In patients with 1.0 – 2.0 cm aNETs, RHC after APY did not confer a survival advantage. No recurrence was seen in patients undergoing APY only, and node positivity was not associated with worse survival. APY alone may be sufficient surgical treatment in this patient population.

Right Hemicolectomy vs. Appendectomy for 1.0 – 2.0 cm Appendiceal Neuroendocrine Tumors: A Mult-Center Cohort Experience

Background: Mechanical complications after total shoulder arthroplasty (TSA) are a major cause of morbidity. Computed-tomography (CT) Hounsfield units (HUs) estimate bone-mineral density (BMD), but their predictive value for TSA mechanical complications is unknown. This study assessed whether glenoid HUs (gHUs) can be used to predict mechanical complication risk.
Methods: In this retrospective cohort study at a single tertiary academic center (January 2011–April 2024), preoperative CT scans from 250 TSAs in 233 patients were independently reviewed by a senior orthopaedic resident, a fellowship-trained shoulder and elbow surgeon, and a musculoskeletal radiologist to measure gHUs. Mechanical complications included periprosthetic or intraoperative fractures and aseptic implant loosening or dissociation were identified and stratified by gHU. Infection and dislocation were excluded. Inter-rater reliability was assessed with the intraclass correlation coefficient (ICC). Receiver operating characteristic (ROC) analysis identified optimal gHU thresholds. Risk-group comparisons used chi-square tests and multivariable logistic regression adjusting for age, sex, body mass index (BMI), and arthroplasty type.
Results: Among 250 TSAs in 233 patients, ICC for gHU measurement was 0.90 (95% CI 0.87–0.92). ROC analysis yielded a cut-off of 177 HU (AUC 0.59; sensitivity 39%; specificity 81%). Mechanical complications occurred in 29% of cases with gHU < 177 versus 13% with gHU ≥ 177 (p = 0.008; adjusted p = 0.02). Patients with gHU < 110 had the highest risk (57% vs 14%; p < 0.001; adjusted p = 0.002).
Conclusions: Preoperative gHU measurements can help to predict increased risk of mechanical complications after TSA. A gHU threshold of 177 HU identifies patients at elevated risk, while gHU < 110 marks the highest-risk group. CT-derived HU may be helpful in guiding preoperative risk stratification, surgical decision making, and surgical planning.


Low Glenoid Hounsfield Units Predicts High Risk of Mechanical Complications After Total Shoulder Arthroplasty

Background 
Osteoarthritis is one of the most prevalent musculoskeletal pathologies worldwide, commonly leading to joint degeneration and downstream functional limitations–it is typically reliant on X-ray based imaging for conclusive diagnosis. The advent of AI-based diagnostic imaging for orthopedics and radiology has imparted an interest in the usage of large language models (LLMs) for clinical usage. This study aims to describe the ability of ChatGPT-4o in correctly distinguishing the presence or lack of osteoarthritis on X-ray through binary classification through a publicly available de-identified dataset. 

Methods 
Using images of 500 knees with osteoarthritis and 500 normal knees–made available through a publicly available, de-identified, expert-labeled dataset from Kaggle–images were recursively looped into the ChatGPT-4o API through a standardized prompt to assess its ability in performing binary classification through the statistical metrics of accuracy, sensitivity, specificity, precision, F1-score, recall, and Chi-squared test. Confidence intervals were calculated to establish posterity for future research. 

Results 
ChatGPT-4o demonstrated mixed performance in the binary classification of knee osteoarthritis. 
It demonstrated a low-to-moderate F1-score (0.670, 95% CI 0.699-0.655), precision (0.517, 
95% CI 0.548-0.501), and accuracy (0.532, 95% CI 0.563-0.516). Low specificity (0.114, 95% CI 0.134-0.104) was also noted. High recall (0.950, 95% CI 0.964-0.943) indicated strong performance in positively identifying osteoarthritis images, with an accompanying Chi-squared test (P<0.001) indicating a lack of randomness in performance, clarifying a strong relationship between ChatGPT-4o’s predictions and the ground truth labels. 

Conclusion 
Our mixed results preclude our conclusion that ChatGPT-4o presents with shortcomings in clinical robustness for osteoarthritis diagnosis, and that physicians should, therefore, exercise caution when considering its usage in clinical environments. Further inquiry is required to better understand the capabilities of AI-driven diagnostics for osteoarthritis imaging, requiring the development of large, high-quality, validated datasets. 


Diagnostic Performance of ChatGPT-4o in Identifying Knee Osteoarthritis from X-ray Imaging

Background
Emergency endotracheal intubation is a critical intervention frequently complicated by hypotension, which can result in poor clinical outcomes. Leveraging machine learning models to predict hypotension based on pre-intubation clinical factors may enhance risk stratification and guide more effective patient management in these critical scenarios.

Methods
A retrospective analysis was conducted on 600 patients aged 18 years or older who required emergency intubation between January 2024 and October 2024. Patient charts were reviewed to collect demographic information, anthropometric data, and hemodynamic parameters recorded within 4 hours prior to intubation. Additional clinical variables and laboratory values were recorded within 48 hours prior to intubation. Patients who were on vasopressor support within 24 hours prior to intubation were recorded. Post-intubation hypotension was defined as the occurrence of any of the following within 30 minutes after intubation: (1) MAP <65 mmHg; (2) a systolic blood pressure <80 mmHg and/or a ≥40% decrease from baseline systolic blood pressure; or (3) initiation or escalation of vasopressors. The predictive performances of these pre-intubation clinical variables were assessed using machine learning algorithms including logistic regression and gradient-boosted decision tree (XGBoost). 

Results
The rate of hypotension following emergency endotracheal intubation was found to be 46% (n=276). Three predictive models were developed: Model 1 incorporated the shock index and related variables, Model 2 included the APACHE II score and associated parameters, and Model 3 integrated the SOFA score with relevant clinical variables. In Model 1, stepwise logistic regression (p<0.05) yielded an AUC of 0.76, with high sensitivity (86%) and key predictors including vasopressor use prior to intubation, modified shock index, and platelet count. Model 2 demonstrated the highest discriminative performance, achieving an AUC of 0.80, with significant contributions from pre-intubation systolic blood pressure, vasopressor use, and platelet count. Model 3 reached an AUC of 0.74, where SOFA score, systolic blood pressure, and age were significantly associated with hypotension. Across all models, XGBoost had AUCs ranging from 0.70 to 0.75.

Conclusion
This study highlights the potential of machine learning models using pre-intubation clinical variables to predict hypotension following emergency endotracheal intubation. Early identification of high-risk patients could allow clinicians to take preventive measures, such as administering low-dose vasopressors, to mitigate the risk of hypotension and its complications. Although the findings are encouraging, additional prospective research involving larger and more diverse cohorts is essential to improve the models’ generalizability and support their integration into routine critical care practice.


Smarter Intubations: ML-Based Prediction of Hypotension Following Emergency Intubation

Introduction: Baclofen is a GABA-B receptor agonist used in the setting of spinal cord injuries to alleviate muscle spasticity by inhibiting excitatory neurotransmission in the spinal cord. Baclofen also possesses the potential to suppress parasympathetic activation of the detrusor muscle, which may impair bladder contraction and promote urinary retention. Urinary retention may lead to prolonged urinary stasis contributing to an increased risk of developing a urinary tract infection (UTI).

Case Description: An 85+ year old female with a past medical history of heart failure, anemia, metastatic spinal cancer, and T12 compression fracture presented to post-acute rehabilitation. The patient reported back discomfort and muscle spasms, and was started on a course of Baclofen 5 mg BID. The following day, she reported symptoms that raised concern for a urinary tract infection and was further evaluated and treated in the hospital.

Conclusion: Through this case report, we emphasize maintaining increased awareness of the potential adverse effects of baclofen on urinary function in order to prompt earlier recognition and management in affected patients. Extensive research is needed to further explore baclofen’s effects on the function of the urinary system.

Baclofen-Associated Urinary Retention and Urinary Tract Infections: A Case Report

Abstract Title
Saving Limbs, Saving Lives: How understanding inpatient diabetes education can change the post-discharge journey

Background
Diabetes is a metabolic condition that affects approximately 11.3% of the United States population (CDC), and approximately 13.2% of the population in Texas specifically (Behavioral Risk Factor Surveillance System (BRFSS)). Worse still, only 50.5% of US adults with diabetes achieve an HbA1c level of less than 7%, indicating poor glycemic control. In summary, the US has a large population that is affected by diabetes, and a significant proportion of that population has uncontrolled disease. One of the major consequences for uncontrolled diabetes is the need for hospitalization and severe complications including lower extremity amputation (LEA), with approximately 82,000 diabetes-related LEA discharges annually. Inpatient diabetes educators play a crucial role in providing patients with self-management education aimed at reducing complications and preventing rehospitalization. Despite its importance, little research exists on the education provided, patient enrollment criteria, and barriers faced by inpatient diabetes educators. Understanding how diabetes education is currently structured in inpatient settings, the challenges educators encounter, and how/if these programs follow up post-discharge is critical to improving educational interventions. With rising diabetes prevalence and frequent hospital readmissions, identifying gaps in inpatient diabetes education is key to improving patient outcomes, decreasing complication burden, and reducing healthcare costs. This research will provide insight to guide future improvements in diabetes education and care transitions. 

Methods
A mixed-methods cross-sectional study will be conducted across four hospital-based diabetes education programs. Diabetes educators completed structured surveys and follow-up interviews assessing criteria for patient inclusion, patient volume, educational content, delivery methods, resource sourcing, validation practices, follow-up protocols, and perceived barriers to education. Survey data will be analyzed using descriptive statistics, and interview transcripts were analyzed thematically.

Results
Our preliminary findings suggest the presence of systemic barriers that hinder access to both inpatient and outpatient diabetes care. Severely ill patients, particularly those hospitalized for diabetes-related complications, often do not receive adequate education or support. Additionally, there appears to be a significant gap in awareness among both patients and providers regarding the availability of free outpatient resources that could substantially benefit this high-risk population.

Conclusion
Findings from this study could inform the development of more consistent, patient-centered, and scalable diabetes education resources. Furthermore, it could more efficiently spread knowledge of existing and underutilized outpatient resources available to vulnerable populations. These insights may guide institutional policy, funding decisions, and future research aimed at improving chronic disease education across diverse healthcare settings.

Saving Limbs, Saving Lives: How understanding inpatient diabetes education can change the post-discharge journey

Objectives: Barriers such as length of training, demanding hours, and workplace culture contribute to childbearing delay and higher rates of infertility among female physicians. This study reviews current literature to assess medical students' attitudes, awareness, and knowledge of physician infertility, as well as to guide the development of evidence-based guidelines for integrating infertility education into medical school curricula to support informed family planning decisions. 
Methods: The literature search was conducted through PubMed and followed PRISMA guidelines. 
Results: Across the literature, themes of limited understanding of fertility amongst medical students, the pressures to delay childbearing, the attitudes of medical students regarding fertility preservation, and a general lack of exposure to fertility preservation options were prevalent. Many studies highlighted gaps in knowledge, anxiety around future fertility, and minimal inclusion of fertility topics in medical school curricula. 
Conclusions: There was a consistent call across the literature for the integration of structured fertility education during medical training. This review emphasizes the importance of equipping students with education on reproductive health, infertility, and fertility preservation options to support personal and professional decision-making. Future efforts should focus on creating inclusive, evidence-based interventions in medical curricula early in training.

Obstacles, Oocytes, and Fertility: A Systematic Review of Medical Student Awareness


Abstract Title: 
Causative Effects of a High Fat Diet on Choroidal Neovascularization: A Gut-Retina Axis Study
Background:
Neovascular age-related macular degeneration (nAMD) is the number one leading cause of irreversible blindness worldwide driven by its hallmark feature: choroidal neovascularization (CNV). Epidemiologic and preclinical studies suggest that high-fat Western-style diets (HFDs) exacerbate AMD progression, potentially through disruption of the gut microbiome. However, prior studies used extreme dietary models or lacked microbiota-controlled systems, limiting translational relevance and mechanistic clarity. We aimed to determine whether real-world Western-style HFDs promote CNV through gut microbiota–dependent mechanisms using a gnotobiotic mouse model.

Methods:
C57BL/6 mice (specific-pathogen-free [SPF] and germ-free [GF]) were fed either a normal diet (ND) or Western-style HFD for 8–20 weeks. A subset of SPF mice received broad-spectrum antibiotics to deplete gut microbiota. CNV was induced via sterile, laser photocoagulation. Fecal microbiota transplantation (FMT) was performed by oral gavage of GF-ND mice with stool from SPF-ND or SPF-HFD donors. Gut microbiota composition was analyzed using 16S rRNA and shotgun metagenomic sequencing. Retinal pigment epithelium (RPE)/choroid transcriptomes were profiled by RNA sequencing, and fecal metabolomics identified microbial-derived metabolites. The effects of butyrate and ursodeoxycholic acid (UDCA) on angiogenesis were tested using an ex vivo choroidal sprouting assay, and immune cell infiltration in the retina was assessed via flatmounts with immunostaining for Iba+ microglia/macrophages.

Results:
HFD-fed SPF mice developed distinct gut dysbiosis, including depletion of Bacteroidetes and enrichment of Clostridiales. These shifts correlated with transcriptional upregulation of angiogenesis and tissue remodeling genes (e.g., VEGF, Egfl7, Adam15, Sox17) in the RPE/choroid. HFD significantly increased CNV lesion size in SPF mice compared to ND (23,549 ± 2,476 µm² vs. 15,272 ± 1,413 µm²; p = 0.005). In contrast, CNV lesions and microglial infiltration were smaller in GF and microbiota-depleted SPF mice, and significantly larger in GF mice receiving FMT from HFD-fed donors. RNA-seq revealed that both HFD and gut microbiota presence altered angiogenesis-related and chromatin remodeling pathways. FMT from HFD mice reduced fecal levels of butyrate and UDCA—two metabolites known to suppress angiogenesis while ex vivo, both compounds inhibited choroidal sprouting in a dose-dependent manner (p < 0.01).

Conclusion:
Our findings establish the first causal link between Western-style high-fat diets and choroidal neovascularization, demonstrating that gut microbiota–dependent dysbiosis drives CNV by altering retinal gene expression and depleting protective microbial metabolites. This work uncovers a novel diet–microbiome–retina axis in AMD pathogenesis and, more importantly, highlights therapeutic opportunities through dietary modification, microbiome-targeted interventions, and restoration of beneficial microbial metabolites such as butyrate and UDCA.


Next from 2025 AMA Research Challenge – Member Premier Access

Safety and Efficacy of CB1 Receptor Antagonists for Weight Reduction: A Meta-Analysis