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Age must be 17 or over

Diagnostic codes for diabetes mellitus

C10.. Diabetes mellitus
C109J Insulin treated Type 2 diabetes mellitus
C109K Hyperosmolar non-ketotic state in type 2 diabetes mellitus
C10C. Diabetes mellitus autosomal dominant
C10D. Diabetes mellitus autosomal dominant type 2
C10E% Type 1 diabetes mellitus
C10F% Type 2 diabetes mellitus (excluding C10F8. Reaven's syndrome)
C10G% Secondary pancreatic diabetes mellitus
C10H% Diabetes mellitus induced by non-steroid drugs
C10M% Lipoatrophic diabetes mellitus
C10N% Secondary diabetes mellitus
PKyP. Diab insipidus,diab mell,optic atrophy and deafness

C10P. Diabetes mellitus in remission (v28)
C10P0 Type I diabetes mellitus in remission (v28)
C10P1 Type II diabetes mellitus in remission (v28)

Without a code for diabetes resolved

21263 Diabetes resolved
212H. Diabetes resolved


DM 017.1 Rationale

The contractor establishes and maintains a register of all patients aged 17 or over with diabetes mellitus which specifies the type of diabetes where a diagnosis has been confirmed

A greater understanding and knowledge of the complexities of diabetes has led to increasing difficulty in accurately diagnosing or classifying the type of diabetes. In March 2011, a report by the Royal College of General Practitioners (RCGP) and NHS Diabetes was published which examined the issue of coding, classification and diagnosis of diabetes in primary care in England. The summary findings of the report included an algorithm to provide guidance to healthcare professionals on making a new diagnosis of diabetes (see www.diabetes.nhs.uk). Following publication of this report, the QOF diabetes register indicator has been expanded to include all types of diabetes within the proposed algorithm. Gestational diabetes will continue to be excluded from this indicator set.

If it is too early in the clinical course to diagnose the specific type of diabetes, or if the specific diagnosis is uncertain, practices are asked to code diabetes using the parent term "Diabetes Mellitus". Practices are expected to update these patient's records when their specific type of diabetes is confirmed. This should generally be within 6-12 months of the initial diagnosis of Diabetes Mellitus.

This indicator does not specify how the diagnosis of diabetes should be made, and a record of the diagnosis will, for the purposes of the QOF, be regarded as sufficient evidence of diabetes. However, there are a substantial number of patients with diabetes who remain undiagnosed and also a number of patients receiving treatment with an incorrect diagnosis of diabetes. Practices are therefore encouraged to adopt a systematic approach to the diagnosis of diabetes.

The World Health Organisation (WHO) 2006 states that fasting plasma glucose >=7.0mmol/l (126mg/dl) or 2-h plasma glucose >= 11.1mmol/l (200mg/dl) should be used as criteria for diagnosing diabetes.

In 2011 an addendum to the 2006 WHO diagnostic criteria was published to allow the use of HbA1c in diagnosing diabetes mellitus27. The addendum does not invalidate the 2006 recommendations on the use of plasma glucose measurements to diagnose diabetes. The WHO recommend that HbA1c can be used as a diagnostic test for diabetes, provided that stringent quality assurance tests are in place and assays are standardised to criteria aligned to theinternational reference values, and there are no conditions present that preclude its accurate measurement. An HbA1c of 48 mmol/mol (6.5%) is recommended as the cut-off point for diagnosing diabetes. A value less than 48 mmol/mol (6.5%) does not exclude diabetes diagnosed using glucose tests. The WHO expert group concluded that there is currently insufficient evidence to make any formal recommendation on the interpretation of HbA1c levels below 48 mmol/mol(6.5%).

The use of HbA1c for diagnosing diabetes can avoid the problem of day-to-day variability of glucose values, and importantly it avoids the need for the patient to make preceding dietary preparations (such as fasting or consuming a glucose drink).

The WHO also recommends that the diagnosis of diabetes in an asymptomatic patient should not be made on the basis of a single abnormal plasma glucose or HbA1c value. At least one additional HbA1c or plasma glucose test result with a value in the diabetic range is required, either fasting, from a random (casual) sample, or from an OGTT.

From April 2014 the business rules for this indicator were updated to include a new Read code for "Diabetes in Remission". Successful management of diabetes with lifestyle, medication, pancreatic or islet cell transplant and/or bariatric surgery may result in glucose levels falling below those diagnostic of diabetes. However these people may still experience the macrovascular and microvascular complications of diabetes and therefore need continued monitoring.Experts from the diabetes classification working group have endorsed the use of this code for people where treatment has normalised hyperglycaemia but still require continued monitoring.

Practices may wish to review their patient records and re-code patients previously coded as " Diabetes Resolved" as "Diabetes in Remission" if they still require monitoring for the reasons outlined above. The use of "diabestes resolved" continues to be appropriate for example in cases of misdiagnosis.

The Royal College of General Practitioners and NHS diabetes (2011) Coding, Classification and Diagnosis of Diabetes. Available from

World Health Organisation (2006) Definition and diagnosis of diabetes mellitus and intermediate hyperglycaemia. Available from

World Health Organisation (2011) Use of glycated haemoglobin (HbA1c) in the diagnosis of diabetes mellitus. Abbreviated report of a WHO consultation. Available from

DM 017.2 Reporting and verification

See indicator wording for requirement criteria.

Verification – The NHS England may require randomly selecting a number of patient records of patients coded with the parent term ‘diabetes mellitus’ and requesting information about how long the specific diagnosis has been unknown.

The NHS England may require contractors to demonstrate that they have processes in place to ensure that patient records are updated once a specific diagnosis has been made. Good practice is that this occurs within six to 12 months of the initial diagnosis.


Prepared By Jean Keenan