Treatment effect heterogeneity following type 2 diabetes treatment with GLP1-receptor agonists and SGLT2-inhibitors: a systematic review
Authors: Young Katherine G. , McInnes Eram Haider , Massey Robert J. , Kahkoska Anna R. , Pilla Scott J. , Raghavan Sridharan , Stanislawski Maggie A. , Tobias Deirdre K. , McGovern Andrew P. , Dawed Adem Y. , Jones Angus G. , Pearson Ewan R. , Dennis John M. ,   ADA/EASD PDMI, Tobias Deirdre K. , Merino Jordi , Ahmad Abrar , Aiken Catherine , Benham Jamie L. , Bodhini Dhanasekaran , Clark Amy L. , Colclough Kevin , Corcoy Rosa , Cromer Sara J. , Duan Daisy , Felton Jamie L. , Francis Ellen C. , Gillard Pieter , Gingras Véronique , Gaillard Romy , Haider Eram , Hughes Alice , Ikle Jennifer M. , Jacobsen Laura M. , Kettunen Jarno L. T. , Kreienkamp Raymond J. , Lim Lee-Ling , Männistö Jonna M. E. , Massey Robert , Mclennan Niamh-Maire , Miller Rachel G. , Morieri Mario Luca , Most Jasper , Naylor Rochelle N. , Ozkan Bige , Patel Kashyap Amratlal , Pilla Scott J. , Prystupa Katsiaryna , Raghaven Sridaran , Rooney Mary R. , Schön Martin , Semnani-Azad Zhila , Sevilla-Gonzalez Magdalena , Svalastoga Pernille , Takele Wubet Worku , Tam Claudia Ha-ting , Thuesen Anne Cathrine B. , Tosur Mustafa , Wallace Amelia S. , Wang Caroline C. , Wong Jessie J. , Yamamoto Jennifer M. , Young Katherine , Amouyal Chloé , Andersen Mette K. , Bonham Maxine P. , Chen Mingling , Cheng Feifei , Chikowore Tinashe , Chivers Sian C. , Clemmensen Christoffer , Dabelea Dana , Dawed Adem Y. , Deutsch Aaron J. , Dickens Laura T. , DiMeglio Linda A. , Dudenhöffer-Pfeifer Monika , Evans-Molina Carmella , Fernández-Balsells María Mercè , Fitipaldi Hugo , Fitzpatrick Stephanie L. , Gitelman Stephen E. , Goodarzi Mark O. , Grieger Jessica A. , Guasch-Ferré Marta , Habibi Nahal , Hansen Torben , Huang Chuiguo , Harris-Kawano Arianna , Ismail Heba M. , Hoag Benjamin , Johnson Randi K. , Jones Angus G. , Koivula Robert W. , Leong Aaron , Leung Gloria K. W. , Libman Ingrid M. , Liu Kai , Long S. Alice , Lowe William L. , Morton Robert W. , Motala Ayesha A. , Onengut-Gumuscu Suna , Pankow James S. , Pathirana Maleesa , Pazmino Sofia , Perez Dianna , Petrie John R. , Powe Camille E. , Quinteros Alejandra , Jain Rashmi , Ray Debashree , Ried-Larsen Mathias , Saeed Zeb , Santhakumar Vanessa , Kanbour Sarah , Sarkar Sudipa , Monaco Gabriela S. F. , Scholtens Denise M. , Selvin Elizabeth , Sheu Wayne Huey-Herng , Speake Cate , Stanislawski Maggie A. , Steenackers Nele , Steck Andrea K. , Stefan Norbert , Støy Julie , Taylor Rachael , Tye Sok Cin , Ukke Gebresilasea Gendisha , Urazbayeva Marzhan , Van der Schueren Bart , Vatier Camille , Wentworth John M. , Hannah Wesley , White Sara L. , Yu Gechang , Zhang Yingchai , Zhou Shao J. , Beltrand Jacques , Polak Michel , Aukrust Ingvild , de Franco Elisa , Flanagan Sarah E. , Maloney Kristin A. , McGovern Andrew , Molnes Janne , Nakabuye Mariam , Njølstad Pål Rasmus , Pomares-Millan Hugo , Provenzano Michele , Saint-Martin Cécile , Zhang Cuilin , Zhu Yeyi , Auh Sungyoung , de Souza Russell , Fawcett Andrea J. , Gruber Chandra , Mekonnen Eskedar Getie , Mixter Emily , Sherifali Diana , Eckel Robert H. , Nolan John J. , Philipson Louis H. , Brown Rebecca J. , Billings Liana K. , Boyle Kristen , Costacou Tina , Dennis John M. , Florez Jose C. , Gloyn Anna L. , Gomez Maria F. , Gottlieb Peter A. , Greeley Siri Atma W. , Griffin Kurt , Hattersley Andrew T. , Hirsch Irl B. , Hivert Marie-France , Hood Korey K. , Josefson Jami L. , Kwak Soo Heon , Laffel Lori M. , Lim Siew S. , Loos Ruth J. F. , Ma Ronald C. W. , Mathieu Chantal , Mathioudakis Nestoras , Meigs James B. , Misra Shivani , Mohan Viswanathan , Murphy Rinki , Oram Richard , Owen Katharine R. , Ozanne Susan E. , Pearson Ewan R. , Perng Wei , Pollin Toni I. , Pop-Busui Rodica , Pratley Richard E. , Redman Leanne M. , Redondo Maria J. , Reynolds Rebecca M. , Semple Robert K. , Sherr Jennifer L. , Sims Emily K. , Sweeting Arianne , Tuomi Tiinamaija , Udler Miriam S. , Vesco Kimberly K. , Vilsbøll Tina , Wagner Robert , Rich Stephen S. , Franks Paul W. 
Published: October 2023

Abstract
Background
A precision medicine approach in type 2 diabetes requires the identification of clinical and biological features that are reproducibly associated with differences in clinical outcomes with specific anti-hyperglycaemic therapies. Robust evidence of such treatment effect heterogeneity could support more individualized clinical decisions on optimal type 2 diabetes therapy.

Methods
We performed a pre-registered systematic review of meta-analysis studies, randomized control trials, and observational studies evaluating clinical and biological features associated with heterogenous treatment effects for SGLT2-inhibitor and GLP1-receptor agonist therapies, considering glycaemic, cardiovascular, and renal outcomes. After screening 5,686 studies, we included 101 studies of SGLT2-inhibitors and 75 studies of GLP1-receptor agonists in the final systematic review.

Results
Here we show that the majority of included papers have methodological limitations precluding robust assessment of treatment effect heterogeneity. For SGLT2-inhibitors, multiple observational studies suggest lower renal function as a predictor of lesser glycaemic response, while markers of reduced insulin secretion predict lesser glycaemic response with GLP1-receptor agonists. For both therapies, multiple post-hoc analyses of randomized control trials (including trial meta-analysis) identify minimal clinically relevant treatment effect heterogeneity for cardiovascular and renal outcomes.

Conclusions
Current evidence on treatment effect heterogeneity for SGLT2-inhibitor and GLP1-receptor agonist therapies is limited, likely reflecting the methodological limitations of published studies. Robust and appropriately powered studies are required to understand type 2 diabetes treatment effect heterogeneity and evaluate the potential for precision medicine to inform future clinical care.