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Riveros, Carlos

https://orcid.org/0000-0001-8030-6605

Mayo Clinic

Houston Methodist

Citations 5

Surgeon-patient Sex Concordance and Long-term Clinical Outcomes and Costs Following Common Surgeries
Thomas, Hannah S. , Satkunasivam, Raj , Coburn, Natalie, Wright, Frances C. , Salles, Arghavan, Riveros, Carlos , Titus, Renil S. , Velasquez, Eusebio Luna, Armstrong, Kathleen, Detsky, Allan S. , Wallis, Christopher J.D., Lin, Lauren, O’Connell, Clare , Coburn, Natalie, Salles, Arghavan , Heybati, Kiyan , Luckenbaugh, Amy N. , Mundra, Vatsala , Velásquez, Eusebio Jesús Luna , Armstrong, Kathleen , Jerath, Angela , Wallis, Christopher J.D.

Annals of Surgery | March 10, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1097/sla.0000000000007047 Get It

Objective: To evaluate the associations between surgeon-patient sex concordance, long-term clinical outcomes and healthcare costs. Background Data: Emerging data suggest surgeon-patient sex concordance may improve short-term outcomes, especially for female patients, yet its long-term effects remain unknown. Methods: We conducted a population-based retrospective cohort study of adults undergoing common surgeries in Ontario, Canada (2007-2019). Patients were followed for 90 and 365 days. Surgeon-patient sex concordance was categorized into four dyads. Multivariate generalized estimating equations clustered by procedure type evaluated composite and individual (complications, readmission, mortality) clinical outcomes and healthcare costs. Results: A total of 1,165,711 patients were included. Female patients treated by male surgeons, compared with female surgeons, were more likely to experience an adverse composite event (90 d: aOR 1.12, 95% CI 1.08–1.17, P <0.001; 365 d: aOR 1.09, 95% CI 1.05–1.14, P <0.001), with no association among male patients (90 d: aOR 1.00, 95% CI 0.94–1.05, P =0.89; 365 d: 0.99, 95% CI 0.92–1.07, P =0.87). Long-term total healthcare costs were greater for patients treated by male surgeons - an effect seen in both male patients (90 d: aRR 1.08, 95% CI 1.03-1.14, P =0.002 and 365 d: aRR 1.08, 95% CI 1.02-1.14, P =0.007) and female patients (90 d: aRR 1.10, 95% CI 1.05-1.14, P <0.001, 365 d: aRR 1.09, 95% CI 1.05-1.14, P <0.001). Conclusions: Surgeon-patient sex concordance was associated with improved long-term outcomes for female, but not male, patients, and female surgeons’ patients had lower healthcare costs. Given these benefits, further investigation into the mechanisms driving these outcomes is warranted.
Surgeon Sex and Postoperative Resource Utilization: A Population-Based Cohort Study
Satkunasivam, Raj , Aminoltejari, Khatereh, Thomas, Hannah S. , Salles, Arghavan , Coburn, Natalie, Wright, Frances C. , McCartney, Colin J. L. , Armstrong, Kathleen , Bass, Barbara L. , Detsky, Allan S. , Riveros, Carlos , Heybati, Kiyan , Coburn, Natalie, Conn, Lesley Gotlib , Luckenbaugh, Amy N. , Ranganathan, Sanjana , Riveros, Carlos , Sutherland, Jason Murray , Jerath, Angela , Wallis, Christopher J D

Annals of Surgery Open | May 2, 2025 | Volume: 6 | Issue: 2 | Pages: e569

10.1097/as9.0000000000000569 Get It

Objectives: To determine associations between physician sex and use of postoperative healthcare resources among patients undergoing common surgeries in Ontario, Canada. Background: Prior studies have shown that patients of female physicians experience better outcomes and have lower healthcare costs compared with patients of male physicians. Understanding differences in resource utilization may offer insights into the care pathways and practice patterns contributing to these differences. Methods: We conducted a population-based, retrospective cohort study of adults (≥18 years of age) undergoing 1 of 25 common surgeries, between January 1, 2007, and December 31, 2019, in Ontario, Canada. The primary outcome was the utilization of one of the following: intensive care unit admission, other medical interventions (eg, tracheostomy, new dialysis starts, and home oxygen), and discharge care needs (eg inpatient rehab, long-term care, and home care use) within 30 days. The data were summarized using descriptive statistics and adjusted using multivariable generalized estimating equations. Results: This population-based study included 1,100,193 patients (61.8% female). Patients treated by male surgeons had higher use of postoperative resources versus those with female surgeons within 30 days (adjusted rate 33.1; 95% confidence interval [CI]: 28.0–39.2 versus 31.2; 95% CI: 25.8–37.7), 90 days, and 1 year. Consistent with these findings, following adjustment for patient, surgeon, procedural, and hospital characteristics, patients treated by male surgeons were significantly more likely to utilize postoperative resources within 30 days (adjusted odds ratio: 1.14; 95% CI: 1.03–1.27; P = 0.010) and at other time points. This difference was primarily driven by the higher use of home care among patients with a male versus female surgeon at all time points (30 days: adjusted odds ratio, 1.13; 95% CI: 1.05–1.21; P = 0.002). Conclusions: Patients with male surgeons had higher postoperative resource utilization when compared with those treated by female surgeons, which was almost entirely driven by the higher use of home care. Further mixed-methods investigation is needed to better understand other potentially relevant factors including surgical outcomes, individual patient preferences, and surgical team decision-making.
Association Between Surgeon Sex and Days Alive at Home Following Surgery: A Population-Based Cohort Study
Heybati, Kiyan , Satkunasivam, Raj , Aminoltejari, Khatereh, Thomas, Hannah S. , Salles, Arghavan , Coburn, Natalie, Wright, Frances C. , Conn, Lesley Gotlib , Riveros, Carlos , McCartney, Colin J. L. , Armstrong, Kathleen , Bass, Barbara L. , Detsky, Allan S. , Coburn, Natalie, Luckenbaugh, Amy N. , Ranganathan, Sanjana , Jerath, Angela , Wallis, Christopher J D

Annals of Surgery Open | July 19, 2024 | Volume: 5 | Issue: 3 | Pages: e477

10.1097/as9.0000000000000477 Get It

Objective: The objective of this study was to measure potential associations between surgeon sex and number of days alive and at home (DAH). Background: Patients treated by female surgeons appear to have lower rates of mortality, complications, readmissions, and healthcare costs when compared with male surgeons. DAH is a validated measure, shown to better capture the patient experience of postoperative recovery. Methods: We conducted a retrospective study of adults (≥18 years of age) undergoing common surgeries between January 01, 2007 and December 31, 2019 in Ontario, Canada. The outcome measures were the number of DAH within 30-, 90-, and 365-days. The data was summarized using descriptive statistics and adjusted using multivariable generalized estimating equations. Results: During the study period, 1,165,711 individuals were included, of which 61.9% (N = 721,575) were female. Those managed by a female surgeon experienced a higher mean number of DAH when compared with male surgeons at 365 days (351.7 vs. 342.1 days; P < 0.001) and at each earlier time point. This remained consistent following adjustment for covariates, with patients of female surgeons experiencing a higher number of DAH at all time points, including at 365 days (343.2 [339.5–347.1] vs. 339.4 [335.9–343.0] days). Multivariable regression modeling revealed that patients of male surgeons had a significantly lower number of DAH versus female surgeons. Conclusions: Patients of female surgeons experienced a higher number of DAH when compared with those treated by male surgeons at all time points. More time spent at home after surgery may in turn lower costs of care, resource utilization, and potentially improve quality of life. Further studies are needed to examine these findings across other care contexts.
Surgeon Sex and Health Care Costs for Patients Undergoing Common Surgical Procedures
Aminoltejari, Khatereh, Kaneshwaran, Kirusanthy , Salles, Arghavan , Buntin, Melinda Beeuwkes, Coburn, Natalie G. , Wright, Frances C. , Conn, Lesley Gotlib , Heybati, Kiyan , Luckenbaugh, Amy N. , Riveros, Carlos , McCartney, Colin J. L. , Bass, Barbara L. , Detsky, Allan S. , Satkunasivam, Raj , Wallis, Christopher J D , Jerath, Angela , Ranganathan, Sanjana , Armstrong, Kathleen

JAMA Surgery | November 29, 2023 | Volume: 159 | Issue: 2 | Pages: 151

10.1001/jamasurg.2023.6031 Get It

ImportancePrior research has shown differences in postoperative outcomes for patients treated by female and male surgeons. It is important to understand, from a health system and payer perspective, whether surgical health care costs differ according to the surgeon’s sex.ObjectiveTo examine the association between surgeon sex and health care costs among patients undergoing surgery.Design, Setting, and ParticipantsThis population-based, retrospective cohort study included adult patients undergoing 1 of 25 common elective or emergent surgical procedures between January 1, 2007, and December 31, 2019, in Ontario, Canada. Analysis was performed from October 2022 to March 2023.ExposureSurgeon sex.Main Outcome and MeasureThe primary outcome was total health care costs assessed 1 year following surgery. Secondarily, total health care costs at 30 and 90 days, as well as specific cost categories, were assessed. Generalized estimating equations were used with procedure-level clustering to compare costs between patients undergoing equivalent surgeries performed by female and male surgeons, with further adjustment for patient-, surgeon-, anesthesiologist-, hospital-, and procedure-level covariates.ResultsAmong 1 165 711 included patients, 151 054 were treated by a female surgeon and 1 014 657 were treated by a male surgeon. Analyzed at the procedure-specific level and accounting for patient-, surgeon-, anesthesiologist-, and hospital-level covariates, 1-year total health care costs were higher for patients treated by male surgeons ($24 882; 95% CI, $20 780-$29 794) than female surgeons ($18 517; 95% CI, $16 080-$21 324) (adjusted absolute difference, $6365; 95% CI, $3491-9238; adjusted relative risk, 1.10; 95% CI, 1.05-1.14). Similar patterns were observed at 30 days (adjusted absolute difference, $3115; 95% CI, $1682-$4548) and 90 days (adjusted absolute difference, $4228; 95% CI, $2255-$6202).Conclusions and RelevanceThis analysis found lower 30-day, 90-day, and 1-year health care costs for patients treated by female surgeons compared with those treated by male surgeons. These data further underscore the importance of creating inclusive policies and environments supportive of women surgeons to improve recruitment and retention of a more diverse and representative workforce.
The Bivalent Bromodomain Inhibitor MT-1 Inhibits Prostate Cancer Growth
Shukla, Sanjeev, Riveros, Carlos , Al-Toubat, Mohammed, Chardon‐Robles, Jonathan, Osumi, Teruko, Serrano, Samuel, Kase, Adam M. , Meurice, Nathalie , Gleba, Justyna, Copland, John A. , Chauhan, Jay, Balaji, K. C., Trynda, Justyna , Balaji, K.C. , Petit, Joachim L. , Gleba, Justyna , Osumi, Teruko, Serrano, Samuel, Fletcher, Steven

Cancers | July 31, 2023 | Volume: 15 | Issue: 15 | Pages: 3851

10.3390/cancers15153851 Get It

Bromodomains (BD) are epigenetic readers of histone acetylation involved in chromatin remodeling and transcriptional regulation of several genes including protooncogene cellular myelocytomatosis (c-Myc). c-Myc is difficult to target directly by agents due to its disordered alpha helical protein structure and predominant nuclear localization. The epigenetic targeting of c-Myc by BD inhibitors is an attractive therapeutic strategy for prostate cancer (PC) associated with increased c-Myc upregulation with advancing disease. MT-1 is a bivalent BD inhibitor that is 100-fold more potent than the first-in-class BD inhibitor JQ1. MT-1 decreased cell viability and causes cell cycle arrest in G0/G1 phase in castration-sensitive and resistant PC cell lines in a dose-dependent fashion. The inhibition of c-Myc function by MT-1 was molecularly corroborated by the de-repression of Protein Kinase D1 (PrKD) and increased phosphorylation of PrKD substrate proteins: threonine 120, serine 11, and serine 216 amino acid residues in β-Catenin, snail, and cell division cycle 25c (CDC25c) proteins, respectively. The treatment of 3D cell cultures derived from three unique clinically annotated heavily pretreated patient-derived PC xenografts (PDX) mice models with increasing doses of MT-1 demonstrated the lowest IC50 in tumors with c-Myc amplification and clinically resistant to Docetaxel, Cabazitaxel, Abiraterone, and Enzalutamide. An intraperitoneal injection of either MT-1 or in combination with 3jc48-3, an inhibitor of obligate heterodimerization with MYC-associated protein X (MAX), in mice implanted with orthotopic PC PDX, decreased tumor growth. This is the first pre-clinical study demonstrating potential utility of MT-1 in the treatment of PC with c-Myc dysregulation.