Back to Authors

Singh, Siddharth

Mayo Clinic

Mayo Clinic in Arizona

Citations 4

Trends in utilization of advanced therapies in patients with inflammatory bowel diseases in the USA, 2021-2025
Singh, Siddharth, Desai, Aakash , Goodwin, Shane W. , Kochhar, Gursimran , Jairath, V , Desai, Aakash

Journal of Crohn’s and Colitis | October 22, 2025 | Volume: 19 | Issue: 10 | Pages: No page available

10.1093/ecco-jcc/jjaf186 Get It

Abstract Background and Aims Seven new advanced therapies, belonging to three new classes, have been approved for the treatment of inflammatory bowel diseases (IBD) since 2021. We examined trends in utilization of advanced therapies in the USA since 2021. Methods Using de-identified electronic health record data from 71 US health systems, we examined quarterly trends in utilization of different advanced therapies in patients with ulcerative colitis and Crohn’s disease between 2021 and 2025, using interrupted time-series analysis utilizing Prais–Winsten regression. Results In 11 093 patients with ulcerative colitis treated with advanced therapies, we observed an increase in use of upadacitinib (12.1% in Q2/2025; P < .001, compared with first quarter of prescription), interleukin-23p19 (IL23p19) antagonists (5.5%; P = .03), and ustekinumab (9.5%; P = .04), decline in use of tumor necrosis factor (TNF) antagonists (34.5%; P = .003), and stable use of vedolizumab (33.6%; P = .17) and sphingosine-1 phosphate receptor modulators (1.6%; P = .28). In 15 951 patients with Crohn’s disease treated with advanced therapies, we observed an increase in use of IL23p19 antagonists (15.0% in Q1/2025; P = .003) and upadacitinib (5.9%; P < .001) and decline in use of TNF antagonists (50.2%; P = .001) and ustekinumab (13.5%; P < .001). Conclusions Contemporary trends in advanced therapy utilization in patients with IBD suggest an increased utilization of upadacitinib and anti-interleukins, accompanied by a decline in use of TNF antagonists in the USA.
The Impact of Setons on Perianal Fistula Outcomes in Patients With Crohn's Disease Treated With Anti‐TNF Therapy: A Multicentre Study
Munir, Javeria, Parlow, Simon , Sambhi, Gagan Deep Singh, Reid, Jacqueline, Yanofsky, Russell , Alenezi, Talal , Meserve, Joseph , Yeh, Kuan‐Hung, Becker, Brenda, Lahijanian, Zubin, Eddin, Anas Hussam, Mallick, Ranjeeta , Rosenfeld, Greg , Bessissow, Ali, Bruining, David H. , Macdonald, Blair , Singh, Siddharth, Parlow, Simon , Jairath, V , McCurdy, Jeffrey D , Yeh, Kuan‐Hung, Ramsay, Tim , Bessissow, Talat , Jairath, Vipul , Macdonald, Blair

Alimentary Pharmacology & Therapeutics | March 18, 2025 | Volume: 61 | Issue: 10 | Pages: 1671-1679

10.1111/apt.70081 Get It

ABSTRACTBackground and AimsWe aimed to assess the impact of setons on perianal fistula outcomes in patients with perianal fistulising Crohn's disease (PFCD) treated with anti‐TNF therapy.MethodsWe included patients treated with their first anti‐TNF therapy for PFCD after undergoing a pelvic MRI between 2005 and 2022 from 6 North American centres. Our exposure was one or more setons at the time of anti‐TNF therapy. Our primary outcome was major adverse fistula outcome (MAFO), a composite of repeat local surgical intervention, hospitalisation, or faecal diversion for PFCD, and our secondary outcome was fistula remission defined clinically. We used 1:1 cardinality matching and propensity score weighting to control for fistula severity based on centrally read MRIs, luminal characteristics, and concomitant therapies.ResultsOur analysis included 221 patients: 81 with setons and 140 without setons. After cardinality matching, our cohorts were balanced (standardised difference < 0.1 for all covariates). Patients with setons had similar rates of MAFO (HR 1.23; 95% CI, 0.68–2.21) and fistula remission at 6 months (OR, 0.81; 95% CI, 0.41–1.59) and 12 months (OR, 0.63; 95% CI, 0.31–1.27) compared to patients without setons. Our results remained stable when analysed by propensity score weighting and in a sensitivity analysis of patients who underwent an exam under anaesthesia. In patients with abscesses, there were lower rates of MAFO (HR, 0.49; 95% CI, 0.19–1.25) but not statistically significant in patients with setons.ConclusionsIn this multicentre, setons were not associated with improved fistula outcomes. Future prospective controlled studies are warranted.
Abstract A44: Coffee consumption and colorectal cancer risk by molecularly defined subtypes in a prospective cohort study of older women
Singh, Siddharth, Tillmans, Lori S. , Wang, Alice , Weisenberger, Daniel J. , Laird, Peter W., Inoue‐Choi, Maki , Mariani, Andrea , Lynch, Charles F. , Anderson, Kristin E. , French, Amy J. , Smyrk, Thomas C. , Thibodeau, Stephen N. , Vierkant, Robert A. , Haile, Robert W. , Harnack, Lisa , Potter, John D. , Slager, Susan L. , Cerhan, James R. , Limburg, Paul J.

Cancer Prevention Research | May 9, 2019 | Volume: 6 | Issue: 11_Supplement | Pages: A44-A44

10.1158/1940-6215.prev-13-a44 Get It

Abstract Background: Different molecules within coffee may be pro-carcinogenic, while others may have anti-oxidant and anti-neoplastic effects. Hence, it can be hypothesized that coffee may have differing risk associations with specific colorectal cancer (CRC) subtypes. The aim of this study was to evaluate associations between coffee consumption and incident CRC overall, by anatomic subsite, and by molecularly defined tumor subtypes, in the population-based Iowa Women's Health Study (IWHS). Methods: IWHS participants, ages 55-69 years, provided dietary intake estimates using self-reported food frequency questionnaires at baseline (1986). From 35,216 women included the final analysis, 1298 developed CRC (673 with proximal CRC, 597 with distal CRC) through December 31, 2002 (end of the IWHS molecular epidemiology project study period). Archived, paraffin-embedded tissue specimens for 732 representative CRC cases were collected and analyzed to determine if coffee consumption (none or &lt;1 cup/month, &lt;1 cup/week, 1 cup/day, 2-3 cups/day and ≥4 cups/day) was associated with microsatellite instability (MSI-L/MSS or MSI-H), CpG island methylator phenotype (CIMP-negative or CIMP-positive), BRAF mutation status (BRAF-wildtype or BRAF-mutated), KRAS mutation status (KRAS-wildtype and KRAS-mutated), p53 protein expression level (p53 absent, low or high) and estrogen receptor β protein expression level (ERβ absent, low or high). Multivariable Cox regression models were fit to estimate relative risks (RR) and 95% confidence intervals (CI) with adjustment for age, smoking, alcohol use, diabetes, body mass index and waist-hip ratio, physical activity, estrogen use, dietary intake of fat, calcium, vitamin E, sucrose, red meat and methionine. P-values were not adjusted for multiple testing. Results: There was no significant difference in the risk of overall (RR, 1.05; 95% CI, 0.85-1.29; Ptrend=0.50), proximal (RR, 0.91; 95% CI, 0.68-1.21; Ptrend=0.57) or distal CRC (RR, 1.18; 95% CI, 0.86-1.64; Ptrend=0.19) in women who consumed ≥4 cups of coffee/day (caffeinated or decaffeinated), as compared to non-consumers. By CRC molecular subtypes for these same two exposure groups, women with ≥4 cups of coffee/day were more likely to develop ERβ-low CRC (RR, 2.98; 95% CI, 1.04-8.51; Ptrend=0.06), though no significant associations were observed for caffeinated or decaffeinated coffee specifically. In contrast, women who consumed ≥4 cups of decaffeinated coffee/day were less likely to develop MSI-L/MSS (RR, 0.57; 95% CI, 0.36-0.92; Ptrend=0.04) and BRAF-WT (RR, 0.69; 95% CI, 0.44-1.06; Ptrend=0.06) CRCs than non-consumers. Women who consumed ≥4 cups of caffeinated coffee/day were also less likely to develop p53-low CRCs (RR, 0.53; 95% CI, 0.24-1.15; Ptrend=0.02). Null associations were observed between decaffeinated coffee consumption and risk of CIMP-, KRAS- and p53- defined CRC subtypes, as well as between caffeinated coffee consumption and risk of MSI-, BRAF-, CIMP- or KRAS-defined CRC subtypes. Conclusion: In this prospective cohort study of older women, though coffee consumption was not associated with risk of overall or site-specific CRC, unique associations were observed with molecularly defined CRC subtypes, supporting a need for further investigation of the potential pro- and anti-carcinogenic effects of coffee constituents on biologic targets involved in colorectal carcinogenesis. Citation Format: Siddharth Singh, Robert Vierkant, Lori Tillmans, Alice Wang, Daniel Weisenberger, Peter Laird, Maki Inoue-Choi, Andrea Mariani, Charles Lynch, Kristin Anderson, Amy French, Robert Haile, Lisa Harnack, John Potter, Susan Slager, Thomas Smyrk, Stephen Thibodeau, James Cerhan, Paul Limburg. Coffee consumption and colorectal cancer risk by molecularly defined subtypes in a prospective cohort study of older women. [abstract]. In: Proceedings of the Twelfth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2013 Oct 27-30; National Harbor, MD. Philadelphia (PA): AACR; Can Prev Res 2013;6(11 Suppl): Abstract nr A44.
Systematic review with meta‐analysis: faecal diversion for management of perianal Crohn's disease
Singh, Siddharth, Ding, Nik S. , Mathis, Kellie L. , Dulai, Parambir S. , Farrell, Ann , Pembérton, John H., Hart, A , Sandborn, William J. , Loftus, Edward V. , Ding, N S , Loftus, Edward V

Alimentary Pharmacology & Therapeutics | August 12, 2015 | Volume: 42 | Issue: 7 | Pages: 783-792

10.1111/apt.13356 Get It

SummaryBackgroundTemporary faecal diversion is sometimes used for management of refractory perianal Crohn's disease (CD) with variable success.AimsTo perform a systematic review with meta‐analysis to evaluate the effectiveness, long‐term outcomes and factors associated with success of temporary faecal diversion for perianal CD.MethodsThrough a systematic literature review through 15 July 2015, we identified 16 cohort studies (556 patients) reporting outcomes after temporary faecal diversion. We estimated pooled rates [with 95% confidence interval (CI)] of early clinical response, attempted and successful restoration of bowel continuity after temporary faecal diversion (without symptomatic relapse), and rates of re‐diversion (in patients with attempted restoration) and proctectomy (with or without colectomy and end‐ileostomy). We identified factors associated with successful restoration of bowel continuity.ResultsOn meta‐analysis, 63.8% (95% CI: 54.1–72.5) of patients had early clinical response after faecal diversion for refractory perianal CD. Restoration of bowel continuity was attempted in 34.5% (95% CI: 27.0–42.8) of patients, and was successful in only 16.6% (95% CI: 11.8–22.9). Of those in whom restoration was attempted, 26.5% (95% CI: 14.1–44.2) required re‐diversion because of severe relapse. Overall, 41.6% (95% CI: 32.6–51.2) of patients required proctectomy after failure of temporary faecal diversion. There was no difference in the successful restoration of bowel continuity after temporary faecal diversion in the pre‐biological or biological era (13.7% vs. 17.6%, P = 0.60), in part due to selection bias. Absence of rectal involvement was the most consistent factor associated with restoration of bowel continuity.ConclusionsTemporary faecal diversion may improve symptoms in approximately two‐thirds of patients with refractory perianal Crohn's disease, but bowel restoration is successful in only 17% of patients.