Hybrid Closed-Loop Therapy in Adults With Type 1 Diabetes and Above-Target HbA1c: A Real-world Observational Study
Authors: Crabtree Thomas S.J. , Griffin Tomás P. , Yap Yew W. , Narendran Parth , Gallen Geraldine , Furlong Niall , Cranston Iain , Chakera Ali , Philbey Chris , Karamat Muhammad Ali , Saraf Sanjay , Kamaruddin Shafie , Gurnell Eleanor , Chapman Alyson , Hussain Sufyan , Elliott Jackie , Leelarathna Lalantha , Ryder Robert E.J. , Hammond Peter , Lumb Alistair , Choudhary Pratik , Wilmot Emma G. ,   The ABCD Closed-Loop Audit Contributors, Evans Mark , Gurnell Eleanor , Hartnell Sara , Davenport Katy , O’Reilly Iona , Brown Helen , Kamaruddin Shafie , Pickering Sharon , Abouglia Kamal , Wadham Claire , Rayman Gerry , Hussain Sufyan , Brackenridge Anna , Pender Siobhan , Atkinson Rosarie , Bahadur Melanie , Eid Hatem , Carling Janet , Oldfield Linzi , Philbey Christopher , Hammond Peter , Haywood Sean , Gallen Geraldine , Rodgers Helen , Lovie Kaylee , Whight Emma , Nobel-Bell Georgia , Harris Sophie , Cartwright Anne , Garnett Ian , Harvey Jennifer , McCulloch Frances , Yap Yew Wen , Weston Philip , Chapman Alyson , Findlow Lynne , Leelarathna Lalantha , Ohol Sheetal , Thabit Hood , Urwin Andrea , Cowlam Darron , Thomas Sonia , Hyland Emma , Yearsley Zoey , Schofield Johnathan , Soar Clare , Fenn Laura , Mendis Budd , Htike Zin Zin , Cheyne Elizabeth , Emsley Julie , Jones Elisabeth , Parfitt Vernon , Sawyer Lynn , Colosimo Santo , Apsara Shani , Mathara Diddhenipothage Dilrukshi , Lumb Alistar , Hards Katie , Edohen Florence , Beaden Sue , Cranston Iain , Taylor Julie , Skinner Lisa , Bawlchhim Zosanglura , Tuthill Bev , Cull Melissa Louise , Ryder Robert E.J. , Mitchell Sarah , Rimell Jill , Foley Clare , Gianfrancesco Carla , Elliott Jackie , Butter Sally , Carrieri Giorgio , Douek Isy , King Rhodri , Lambert Paul , Lionetti Paula , Cardwell Janet , Furlong Niall , Keigan Suzanne , Milne Rachael , Wilkinson Philomena , Ashton-Cleary Siobhan , White Sarah , Anthony Karen , Ribul Mazzola Stefania , Sweeney Stephanie , Narendran Parth , Karamat Ali , Saraf Sanjay , Hudson Barbara , Li Manyee , Skelding Rebecca , Williams Lisa , Bartha Karen , Jesson Anna-Marie , Grandy Lynn , Brewer Deborah , Edwards Joanne , Sears Nicola , Shergil Manjit , Baldwin Andy , Crabtree Thomas , Van Heeswijk Isabelle , Langeland Linn , Taylor Nicola , Wilmot Emma , Owen Sarah , Taylor Rachel , Robinson Emma , Bakhit Mohammed , Redfern Amy , Kedge Cathy , Kotonya Christine , Hayat Haleema , Gerrard Katy , Pearson Nicci , Redfern Zara , Curtis Louise , Galea Alison , Weiss Melanie , Stacey Nikki , Partridge Helen , Choudhary Pratik , Griffin Tomás , Ackroyd Dawn , Turrell Liz , Chakera Ali J. , Lambert Vicki , Suarez Alison , Kirby Jesina , Lloyd Nicola , Karathenasi Eleni , McKinnon Samantha , Levitt Mindy , Govindan Raj , Haskoll Becky , Saunders Simon , Kehinde Razak , Lee James , Galliford Thomas , Bickerton Alex , Hammond Ruth , Walker Ruth 
Published: August 2023

OBJECTIVE
We explored longitudinal changes associated with switching to hybrid closed-loop (HCL) insulin delivery systems in adults with type 1 diabetes and elevated HbA1c levels despite the use of intermittently scanned continuous glucose monitoring (isCGM) and insulin pump therapy.

RESEARCH DESIGN AND METHODS
We undertook a pragmatic, preplanned observational study of participants included in the National Health Service England closed-loop pilot. Adults using isCGM and insulin pump across 31 diabetes centers in England with an HbA1c ≥8.5% who were willing to commence HCL therapy were included. Outcomes included change in HbA1c, sensor glucometrics, diabetes distress score, Gold score (hypoglycemia awareness), acute event rates, and user opinion of HCL.

RESULTS
In total, 570 HCL users were included (median age 40 [IQR 29–50] years, 67% female, and 85% White). Mean baseline HbA1c was 9.4 ± 0.9% (78.9 ± 9.1 mmol/mol) with a median follow-up of 5.1 (IQR 3.9–6.6) months. Of 520 users continuing HCL at follow-up, mean adjusted HbA1c reduced by 1.7% (95% CI 1.5, 1.8; P &lt; 0.0001) (18.1 mmol/mol [95% CI 16.6, 19.6]; P &lt; 0.0001). Time in range (70–180 mg/dL) increased from 34.2 to 61.9% (P &lt; 0.001). Individuals with HbA1c of ≤58 mmol/mol rose from 0 to 39.4% (P &lt; 0.0001), and those achieving ≥70% glucose time in range and &lt;4% time below range increased from 0.8 to 28.2% (P &lt; 0.0001). Almost all participants rated HCL therapy as having a positive impact on quality of life (94.7% [540 of 570]).

CONCLUSIONS
Use of HCL is associated with improvements in HbA1c, time in range, hypoglycemia, and diabetes-related distress and quality of life in people with type 1 diabetes in the real world.