Earlier Diagnosis, Earlier Support: What the HbA1c Criteria Change Means for Primary Care

From 1 July 2026, Aotearoa New Zealand will lower the HbA1c threshold for diagnosing diabetes from 50 mmol/mol to 48 mmol/mol, aligning national criteria with international standards.

Ahead of the national implementation date, Comprehensive Care PHO, in collaboration with Health New Zealand | Te Whatu Ora, convened a webinar for primary care clinicians to support early understanding, practical planning and consistent implementation across general practice.

Delivered in collaboration with Health New Zealand | Te Whatu Ora, the session was presented by Dr Ryan Paul, endocrinologist at Health New Zealand | Te Whatu Ora Waikato, Associate Professor at the University of Waikato and Co-Chair of Mahitahi Matehuka, the Diabetes National Clinical Network.

For primary care, the message was clear: the diagnostic threshold is changing, but the clinical intent remains focused on earlier recognition, earlier support and better long-term outcomes for patients and whānau.

What is changing

From 1 July 2026, the HbA1c diagnostic bands will be:

Normoglycaemia: 41 mmol/mol or lower

Prediabetes: 42 to 47 mmol/mol

Diabetes: 48 mmol/mol or higher

The glucose diagnostic criteria are not changing.

A confirmatory test is no longer required when HbA1c is 53 mmol/mol or higher. For HbA1c results between 48 and 52 mmol/mol, a confirmatory test should be completed as soon as practical. Depending on the clinical context, this may be a repeat HbA1c, fasting glucose, or random glucose if the person is symptomatic.

The change brings Aotearoa into alignment with World Health Organization and other international diagnostic standards.

Why earlier diagnosis matters

Diabetes remains one of New Zealand’s most significant long-term health conditions and a leading cause of death and health loss. It is also a major driver of preventable vision loss, dialysis, lower-limb amputation, infection, fractures and reduced mobility.

The burden is not shared equally. Pacific peoples experience diabetes at four times the rate of European people, while Māori are dying from diabetes at 2.5 times the rate of non-Māori. Māori, Pacific, Indian and low-income populations are disproportionately affected and stand to benefit most from earlier, correct diagnosis and timely intervention.

Lowering the diagnostic threshold is designed to support earlier action, particularly for people who develop diabetes earlier in life. Earlier diagnosis creates an opportunity to alter the course of type 2 diabetes, support remission, reduce complications and improve equity.

Supporting practices to prepare

The change is significant, but it is intended to be manageable for primary care.

A key focus of the webinar was translating the national criteria change into practical steps for general practice. By bringing clinical leadership and implementation guidance directly to practices ahead of the go-live date, Comprehensive Care aimed to help teams prepare early, reduce uncertainty and support a consistent approach across the network.

The initial focus is on about 12,500 New Zealanders with new-onset diabetes aged under 60. Nationally, this equates to about nine people per practice with diabetes who are not currently receiving treatment.

Practices that are clinically and operationally ready can apply the new criteria now, including to historical HbA1c results of 48 to 49 mmol/mol in the past six to 12 months.

From 1 July, standardised national laboratory reporting will go live across the motu, aligned with NZSSD guidance. Awanui Labs implemented the change on 20 May 2026 and began flagging HbA1c results of 42 mmol/mol or higher with interpretive comments.

For practices, the key task is to consider how patients not yet receiving treatment can be identified and supported. A mix of active recall, annual reviews and patient-initiated contact may be appropriate, depending on clinical priority and practice capacity.

Management remains unchanged

Recommended management does not change.

For people newly diagnosed with type 2 diabetes, first-line care remains healthy lifestyle support and medication where appropriate. Cardiovascular risk management remains essential, including blood pressure, lipids, smoking cessation and wider risk factor management.

The webinar also reinforced the need to reduce clinical inertia. Earlier diagnosis should prompt earlier support, not simply a change in coding.

Clinicians should continue to consider whether the presentation is consistent with type 2 diabetes or whether another type of diabetes may be present. Red flags include younger age, normal weight or underweight presentation, rapid deterioration in glycaemia, marked symptoms, or clinical concern for type 1 diabetes or pancreatogenic diabetes. In these cases, further investigation and discussion with specialist services may be appropriate.

Retinal photoscreening: what to note

Retinal photoscreening was one of the key practical considerations discussed during the webinar.

Photoscreening can be deferred for up to three years in selected new-onset cases, such as type 2 diabetes where HbA1c was below 48 mmol/mol in the past 12 months, unless there are specific clinical concerns.

Referral should be made at diagnosis where there is uncertainty about the timing of onset, where there are specific clinical concerns, or where the person is diagnosed with HbA1c of 50 mmol/mol or higher.

Practices are encouraged to include relevant HbA1c and onset information in retinal photoscreening referrals so providers can triage appropriately. Where local retinal screening systems cannot hold a patient for deferred screening, practices may need to manage the recall within their practice management system.

A wider direction of travel

The HbA1c criteria change sits within a broader national focus on diabetes, cardiovascular, kidney and metabolic health.

The presentation highlighted the importance of moving care upstream, strengthening earlier intervention and supporting primary care to focus capacity where it can have the greatest impact.

Earlier lifestyle and metformin care is expected to be cost-saving downstream, while earlier detection and intervention can help delay and slow cardiovascular, kidney and eye disease.

For Comprehensive Care, the change also reflects the importance of proactive clinical communication. National changes are most effective when they are understood early, interpreted clearly and supported with practical guidance that reflects the realities of general practice.

Comprehensive Care’s role

Comprehensive Care is committed to supporting practices with timely, clinically relevant education that helps translate national changes into practical primary care action.

By convening this webinar ahead of implementation, we created an opportunity for clinicians to hear directly from national diabetes leadership, clarify practical questions and consider how the new criteria can be applied safely and consistently in their own practice settings.

As practices begin applying the new HbA1c criteria, we will continue to share relevant updates, resources and guidance with the network. The aim is to support consistent implementation, strengthen clinical confidence and help primary care teams focus their capacity where it will make the greatest difference.

Earlier diagnosis is not just a change in numbers. It is an opportunity to act sooner, support whānau earlier and reduce the long-term burden of diabetes across our communities.