Background: Glycated haemoglobin (HbA1c) measurement is used for diagnosis, management and remission of type 2 diabetes (T2DM), with measurements comparable worldwide and the World Health Organization listing medical conditions that affect its accuracy. Admission glucose is in the ‘diabetes’ range in 5% of emergency hospital admissions without prior diagnosis, with literature searches indicating inconsistent practice on using HbA1c to confirm diagnosis. As oral glucose tolerance tests (OGTT) were not possible during the COVID-19 pandemic, guidance was issued by the Royal College of Obstetrics and Gynaecology on using HbA1c for gestational diabetes mellitus. Aims: This study explores use of HbA1c at Queen Elizabeth Hospital Birmingham, a large university hospital serving a multi- ethnic adult population. Methods: Information is presented on comparability, clinical audits, research studies and current practice, and is illustrated by case reports. Results: Data from the National Glycohemoglobin Standardization Program show comparability of laboratoryHbA1c and point-of-care testing methods from 1993 to 2023. Although HbA1c was used to diagnose gestational diabetes during the COVID-19 pandemic, hospitals have reverted to OGTT post pandemic. In contrast, HbA1c is now being used to assess T2DM remission. Case reports illustrate these scenarios and highlight the complexity of decision-making when the accuracy of the HbA1c reading is affected by multiple co- morbidities. Conclusions: This wider use of HbA1c includes remission of T2DM but the diagnosis of gestational diabetes has reverted to OGTT post pandemic. A pictorial representation of HbA1c range is presented to aid understanding of this test. It is suitable for diagnosis of diabetes in most people except those with some variant haemoglobins or abnormal red blood cell turnover.

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Medical conditions can affect haematological factors altering relationship between HbA1c and glucose. Patients were recruited at hospital over 3 visits (*1/**2&3 only) comprising 20 with diabetes and in Fig 1 with liver disease (LD) & hepatitis C (HC) on ribavirin*, on dapsone*, with macrocytosis, and in Fig 2 LD & HC off ribavirin**, LD with nonalcoholic steatohepatitis and cirrhosis, rheumatoid arthritis, renal disease on erythropoietin (EPO) , renal disease off EPO and with microcytosis. Glucose and full blood count were measured with HbA1c on Tosoh G8 analysers, ref range 20-42mmol/mol. In Fig 1 HbA1c was more depressed relative to glucose than Fig 2, both p<0.001, with a combination of lower red blood cell (rbc) count & higher mean cell volume. The macrocytic nature of rbc implies faster turnover and less contact of haemoglobin with circulating glucose. Disclosure A. Karwath: None. J.A. Williams: None. R.A. Round: None. G. Gkoutos: None. G. Roberts: None. J. Webber: None. Funding Medical Research Council (MR/S003991/1) , MRC HDR UK (HDRUK/CFC/01) , NIHR Birmingham ECMC, NIHR Birmingham SRMRC, Nanocommons H2020-EU (731032) , MAESTRIA (Grant agreement ID 965286)

The UK Biobank recruited 502,481 people aged 40 to 70 years who were invited to participate by post so not necessarily representative of the general population. The 405,363 participants with random glucose, HbA1c and the necessary demographic/clinical data were aged 56.5 (8.09) years, mean SD, with 54% female, and ethnicity 95.0% White W, 1.9 South Asian SA, 1.3% Black B, 0.9% Other O, 0.6% Mixed Background MB, and 0.3% Chinese C. Glucose was measured by hexokinase and HbA1c by BioRad VARIANT II TURBO analysers, reference range 20-42 mmol/mol in a dedicated central laboratory. Cohen's D statistic was used to compare glucose/HbA1c by ethnicity versus the largest group W. Mean glucose ranged from 5.04 to 5.41 mmol/L with HbA1c40.7 mmol/mol for SAversus36.0 for W (D=0.78 medium effect M) , B 39.3 (D=0.51 M) , O 38.4 (D=0.37 small S) , C 37.1 (D=0.17 very small V) & MB 36.6 (D=0.09 V) , all p values <0.001. There were large differences by ethnicity in linear regression slopes for the glucose/HbA1c relationship when compared to W with correlation coefficient comparison Z-statistics for SA 16.74, B 8.69, O 10.94, C 8.96, all p<0.001, except for MB 2.56, p=0.01. Such ethnic differences in HbA1c have been reported previously and questions raised as whether different cut-offs should be used for diagnosis of diabetes. However, more information on the prevalence of microvascular complications and differences in haematological profiles is required for such modifications. Disclosure J. A. Williams: None. S. E. Manley: n / a. A. Karwath: None. R. A. Round: None. I. M. Stratton: None. S. Ghosh: Other Relationship; Boehringer Ingelheim International GmbH, Eli Lilly and Company, Novo Nordisk. S. Mostafa: None. G. Roberts: None. J. Webber: None. G. Gkoutos: None. Funding Medical Research Council (MR/S003991/1) , MRC HDR UK (HDRUK/CFC/01) , NIHR Birmingham ECMC, NIHR Birmingham SRMRC, Nanocommons H2020-EU (731032) , MAESTRIA (965286)

The prevalence of diabetes in Birmingham is 11% but it is 22% in hospital inpatients. Queen Elizabeth Hospital in Birmingham (QEHB) serves a multi-ethnic population with 6% Afro-Caribbean, 19% South Asian and 70% White European. A clinical audit of 18,965 emergency admissions to QEHB showed that 5% were undiagnosed but had admission glucose in the ‘diabetes’ range and 16% were in the ‘at risk’ range. The proportion of Afro-Caribbeans (7%) and South Asians (8%) in the ‘diabetes’ range was higher than White Europeans (5%). Given the magnitude of the problem, this paper explores the issues concerning the use of reflex HbA1c testing in the UK for diagnosis of diabetes in hospital admissions. HbA1c testing is suitable for most patients but conditions affecting red blood cell turnover invalidate the results in a small number of people. However, there are pertinent questions relating to the introduction of such testing in the NHS on a routine basis. Literature searches on a topical question ‘Is hyperglycaemia identified during emergency admission/attendance acted upon?’, were performed from 2016 to 2021 and 2016 to 2022. They identified 21 different, relevant, research papers - 5 from Australia, 9 from Europe including 4 from the UK, 5 from America and 1 each from Canada and Africa. These papers revealed an absence of established procedures for the management and follow-up of routinely detected hyperglycaemia using HbA1c when no previous diabetes diagnosis was recorded. Further work is required to determine the role of reflex HbA1c testing for diagnosis of diabetes in admissions with hyperglycaemia, and the cost-effectiveness and role of point-of-care HbA1c testing.

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Abstract Aims To establish the prevalence of admission plasma glucose in 'diabetes' and 'at risk' ranges in emergency hospital admissions with no prior diagnosis of diabetes; characteristics of people with hyperglycaemia; and factors influencing glucose measurement. Methods Electronic patient records for 113 097 hospital admissions over 1 year from 2014 to 2015 included 43 201 emergencies with glucose available for 31 927 (74%) admissions, comprising 22 045 people. Data are presented for 18 965 people with no prior diagnosis of diabetes and glucose available on first attendance. Results Three quarters (14 214) were White Europeans aged 62 (43‐78) years, median (IQ range); 12% (2241) South Asians 46 (32‐64) years; 9% (1726) Unknown/Other ethnicities 43 (29‐61) years; and 4% (784) Afro‐Caribbeans 49 (33‐63) years, P < .001. Overall, 5% (1003) had glucose in the 'diabetes' range (≥11.1 mmol/L) higher at 8% (175) for South Asians; 16% (3042) were ‘at risk’ (7.8‐11.0 mmol/L), that is 17% (2379) White Europeans, 15% (338) South Asians, 14% (236) Unknown/Others and 11% (89) Afro‐Caribbeans, P < .001. The prevalence for South Asians aged <30 years was 2.1% and 5.2%, respectively, 2.6% and 8.6% for Afro‐Caribbeans <30 years, and 2.0% and 8.4% for White Europeans <40 years. Glucose increased with age and was more often in the 'diabetes' range for South Asians than White Europeans with South Asian men particularly affected. One third of all emergency admissions were for <24 hours with 58% of these having glucose measured compared to 82% with duration >24 hours. Conclusions Hyperglycaemia was evident in 21% of adults admitted as an emergency; various aspects related to follow‐up and initial testing, age and ethnicity need to be considered by professional bodies addressing undiagnosed diabetes in hospital admissions.

Introduction: As HbA1c is now widely used for the diagnosis of diabetes with WHO cut-off ≥ 48 mmol/mol/6.5%, it is debatable whether the value should vary by ethnicity. Aim: This study compares plasma glucose and HbA1c in white European WE, South Asian SA, unknown/other U and Afro-Caribbean AC people admitted as an emergency. Methods: Electronic patient records were interrogated over 1 year (2014/5) for a clinical audit, CARMS-12031R. Glucose was measured on wards with meters/gas machines or the laboratory along with HbA1c on Tosoh G8 HPLC analysers if haemoglobin normal. Results: There were 30,664 people of whom 22,045 (72%) had glucose recorded and 2,083 (7%) HbA1c. 1,904 (6%) had both glycaemic markers and were aged 64 (50-78) years, median (IQ range); 839 (44%) female; 560 (29%) prior diabetes diagnosis; 1,405 (74%) WE, 296 (16%) SA, 112 (6%) U and 91 (5%) AC. Glucose was 7.4 (5.8-10.6), 8.6 (6.2-12.3), 8.1 (5.9-10.7), 7.0 (5.9-11.6) mmol/L and HbA1c 42 (37-55), 50 (41-70), 42 (38-60), 46 (39-70) mmol/mol/6.0 (5.5-7.2), 6.7 (5.9-8.6), 6.0 (5.6-7.6), 6.4 (5.7-8.6)%, respectively. HbA1c was higher relative to glucose in SA and AC compared to WE and U, p<0.001. Conclusions: Haematological differences related to red blood cell turnover may account for the variance; this should be recognised by those involved in producing protocols/guidelines for diagnosis. More research is required on using HbA1c to confirm undiagnosed diabetes in admissions. Disclosure S.E. Manley: None. R. Susarla: None. R.A. Round: None. P. Nightingale: None. J.A. Williams: None. I.M. Stratton: Consultant; Self; Novo Nordisk A/S. Research Support; Self; Bayer AG, Boehringer Ingelheim International GmbH. J. Webber: None. G. Gkoutos: None. W. Hanif: Advisory Panel; Self; Boehringer Ingelheim International GmbH. Consultant; Self; Novo Nordisk A/S. Research Support; Self; AstraZeneca, Janssen Diagnostics, Sanofi. Speaker's Bureau; Self; AstraZeneca, Novartis AG, Novo Nordisk A/S. G. Roberts: None. S. Ghosh: Advisory Panel; Self; Abbott. Other Relationship; Self; Mylan.

Objective: Glucose is measured on hospital admission as an emergency as elevated glucose is associated with an eight-fold risk of dying in hospital. This study reports on admission plasma glucose by ethnicity in people without prior diabetes. Research Design and Methods: A clinical audit CARMS-12031 of electronic patient records for 113,097 admissions to hospital over 1 year from April 2014 to March 2015 identified 43,201 emergency admissions with glucose unavailable for 11,274 (26%). Of 5,867 admissions with prior diabetes coding, 5,523 (94%) had glucose recorded. First attendances were analyzed for emergency admissions with no record of diabetes. Results: Of these 18,965 people admitted, 75% were White Europeans WE who were older than South Asians SA 12%, unknown/other ethnic groups U 9%, and Afro-Caribbeans AC 4%. 1,003 people admitted as an emergency had glucose in ‘diabetes range’ (≥11.1mmol/L) and 3,042 in ‘at risk’ range (7.8 to 11.0mmol/L). More SA 8% had glucose in diabetes range than WE 5% and also than U 5%; there were significantly more WE 17% in ‘at risk’ range than U 14% or AC 11%. Higher glucose was observed in SA and U men than women, p = 0.005 and p = 0.018, respectively. Conclusions: Protocols should target people requiring additional HbA1c testingto diagnose undiagnosed diabetes on hospital admission especially younger SA and AC individuals, and outline appropriate clinical intervention. Disclosure S. Ghosh: Advisory Panel; Self; Abbott. Other Relationship; Self; Mylan. R. Susarla: None. R.A. Round: None. P. Nightingale: None. J.A. Williams: None. I.M. Stratton: Consultant; Self; Novo Nordisk A/S. Research Support; Self; Bayer AG, Boehringer Ingelheim International GmbH. G. Gkoutos: None. J. Webber: None. W. Hanif: Advisory Panel; Self; Boehringer Ingelheim International GmbH. Consultant; Self; Novo Nordisk A/S. Research Support; Self; AstraZeneca, Janssen Diagnostics, Sanofi. Speaker's Bureau; Self; AstraZeneca, Novartis AG, Novo Nordisk A/S. G. Roberts: None. S.E. Manley: None.

Steroid-induced hyperglycaemia (SIH) is a common adverse effect in patients both with and without diabetes. This project aimed to improve the screening and diagnosis of SIH by improving the knowledge of healthcare professionals who contribute to the management of SIH in hospitalised patients. Monitoring and diagnosis of SIH were measured in areas of high steroid use in our hospital from May 2016 to January 2017. Several interventions were implemented to improve knowledge and screening for SIH including a staff education programme for nurses, healthcare assistants and doctors. The Trust guidelines for SIH management were updated based on feedback from staff. The changes to the guideline included shortening the document from 14 to 4 pages, incorporating a flowchart summarising the management of SIH and publishing the guideline on the Trust intranet. A questionnaire based on the recommendations of the Joint British Diabetes Societies for SIH was used to assess the change in knowledge pre-intervention and post-intervention. Results showed an increase in junior doctors’ knowledge of this topic. Although there was an initial improvement in screening for SIH, this returned to near baseline by the end of the study. This study highlights that screening for SIH can be improved by increasing the knowledge of healthcare staff. However, there is a need for ongoing interventions to sustain this change.

To assess the current knowledge and practice for monitoring and diagnosis of steroid-induced hyperglycaemia (SIH) in hospitalised patients. This study was undertaken on six wards with high frequency of steroid use – oncology, respiratory and neurology – at a large tertiary care centre in the

Objective: WHO, IDF and ADA recommend HbA(1c) >= 6.5% (48 mmol/mol) for diagnosis of diabetes with pre-diabetes 6.0% (42 mmol/mol) [WHO] or 5.7% (39 mmol/mol) [ADA] to 6.4% (47 mmol/mol). We have compared HbA(1c) from several methods for research relating glycaemic markers.Research design and methods: HbA(1c) was measured in EDTA blood from 128 patients with diabetes on IE HPLC analysers (Bio-Rad Variant II NU, Menarini HA8160 and Tosoh G8), point of care systems, POCT, (A1cNow+ disposable cartridges and DCA 2000 (R)+ analyser), affinity chromatography (Primus Ultra2) and the IFCC secondary reference method (Menarini HA8160 calibrated using IFCC SRM protocol).Results: Median (IQ range) on IFCC SRM was 7.5% (6.8-8.4) (58(51-68) mmol/mol) HbA(1c) with minimum 5.3%(34 mmol/mol)/maximum 11.9%(107 mmol/mol). There were positive offsets between IFCC SRM and Bio-Rad Variant II NU, mean difference (1SD), +0.33%(0.17) (+3.6(1.9) mmol/mol), r(2) = 0.984, p < 0.001 and Tosoh G8, +0.22%(0.20) (2.4(2.2) mmol/mol), r(2) = 0.976, p < 0.001 with a very small negative difference -0.04%(0.11) (-0.4(1.2) mmol/mol), r(2) = 0.992, p < 0.001 for Menarini HA8160. POCT methods were less precise with negative offsets for DCA 2000 (R)+ analyser -0.13%(0.28) (-1.4(3.1) mmol/mol), r(2) = 0.955, p < 0.001 and A1cNow+ cartridges -0.70%(0.67) (-7.7(7.3) mmol/mol), r(2) = 0.699, p < 0.001 (n = 113). Positive biases for Tosoh and Bio-Rad (compared with IFCC SRM) have been eliminated by subsequent revision of calibration.Conclusions: Small differences observed between IFCC-calibrated and NGSP certified methods across a wide HbA(1c) range were confirmed by quality control and external quality assurance. As these offsets affect estimates of diabetes prevalence, the analyser (and calibrator) employed should be considered when evaluating diagnostic data. (C) 2014 Elsevier Ireland Ltd. All rights reserved.