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Type 2 diabetes in adults

Last reviewed: 8 Apr 2025
Last updated: 20 Nov 2024

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • asymptomatic
  • polydipsia
  • polyuria
Full details

Other diagnostic factors

  • candidal infections
  • skin infections
  • urinary tract infections
  • fatigue
  • blurred vision
  • polyphagia
  • unintentional weight loss
  • paraesthesias
  • acanthosis nigricans
Full details

Risk factors

  • older age
  • overweight/obesity
  • gestational diabetes
  • non-diabetic hyperglycaemia
  • family history of type 2 diabetes
  • non-white ancestry
  • polycystic ovary syndrome
  • hypertension
  • dyslipidaemia
  • cardiovascular disease
  • stress
Full details

Diagnostic investigations

1st investigations to order

  • fasting plasma glucose
  • HbA1c
  • 2-hour post-load glucose after 75 g oral glucose
  • random plasma glucose
Full details

Investigations to consider

  • fasting lipid profile
  • urine ketones
  • albumin to creatinine ratio (ACR)
  • serum creatinine and estimated GFR
  • ECG
  • ankle-brachial pressure index (ABPI)
  • random C-peptide
  • autoantibody testing
  • liver function tests (LFTs)
Full details

Treatment algorithm

INITIAL

at initial diagnosis

ACUTE

HbA1C above goal: non-pregnant

HbA1C above agreed threshold on initial pharmacotherapy or cardiovascular risk changes: non-pregnant

pregnant

Contributors

Authors

Surya Rajeev, MBBS, MRCP, MD

Consultant Physician and Clinical Director

Department of Diabetes and Endocrinology

Liverpool University Hospital NHS Foundation Trust

UK

Disclosures

SR has received reimbursement from Novo Nordisk for conferences, and has presented paid lectures.

Acknowledgements

Dr Surya Rajeev would like to gratefully acknowledge Dr Partha Kar, Dr Amar Puttanna, Dr Patrick J. O'Connor and Dr JoAnn M. Sperl-Hillen, the previous contributors to this topic.

Disclosures

PK has sat on advisory boards and attended events reimbursed by Novo Nordisk, Eli Lilly, and Sanofi. AP has received honoraria from Napp, Novo Nordisk, Sanofi, Lilly-Boehringer Ingelheim, Daiichi-Sankyo, and AstraZeneca for presentation at meetings, conference registration, or participating in advisory boards. PJO receives research funding from the National Institutes of Health on multiple projects and is an author of a number of references cited in this topic. JMS-H is an author of a number of references cited in this topic and is an inventor on a US patent for Disease Treatment Simulation, a simulation-based technology developed without commercial support to educate health providers on chronic disease management in a virtual environment.

Peer reviewers

Vinod Patel, MD, FRCP, FHEA, MRCGP, DRCOG, MBChB, BSc (Hons), RCPathME

Professor, Diabetes and Clinical Skills

Warwick Medical School

University of Warwick

Hon Consultant in Endocrinology and Diabetes, Acute Medicine, Medical Obstetrics

Diabetes and Endocrinology Centre

George Eliot Hospital NHS Trust

Nuneaton

Clinical Director for Diabetes West Midlands Clinical Networks & Clinical Senate

NHS England and NHS Improvement - Midlands

UK

Disclosures

VP declares he has worked with most of the large pharmaceutical industry groups over the years with the majority of the work being in education of healthcare professionals in diabetes care. This includes Novo Nordisk, Eli Lily, MSD, BI, Sanofi, Napp, Internis, Takeda, and AZ. VP has been part of advisory board work on occasions. VP has received conference arrangements and lecture fees. VP is a trustee of the charity South Asian Health Foundation.

Gregory Lip, MD, FRCP, DFM, FACC, FESC, FEHRA

Price-Evans Professor of Cardiovascular Medicine

University of Liverpool

Senior Investigator

National Institute for Health Research

UK

Distinguished Professor

Faculty of Medicine

Aalborg University

Denmark

Adjunct Professor

Yonsei University

Seoul

South Korea

Disclosures

GL has acted as a consultant and speaker for BMS/Pfizer, Boehringer Ingelheim, and Daiichi-Sankyo.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

National Institute for Health and Care Excellence. Type 2 diabetes in adults: management. Jun 2022 [internet publication].Full text

Marx N, Federici M, Schütt K, et al. 2023 ESC Guidelines for the management of cardiovascular disease in patients with diabetes. Eur Heart J. 2023 Oct 14;44(39):4043-140.Full text  Abstract

National Institute for Health and Care Excellence. Diabetes in pregnancy: management from preconception to the postnatal period. Dec 2020 [internet publication].Full text

Davies MJ, Aroda VR, Collins BS, et al. Management of hyperglycemia in type 2 diabetes, 2022. A consensus report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD). Diabetes Care. 2022 Nov 1;45(11):2753-86.Full text  Abstract

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.
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  • Guidelines

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    • Management of hyperglycaemia in type 2 diabetes, 2022
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