The long-awaited NICE guideline ‘Type 2 diabetes in adults: management’ (new guideline [NG] 28) was finally published on 2nd December 2015, almost eleven months after the first draft was released. The first draft caused uproar in the diabetes community and led to the highly unusual step of NICE issuing a second draft for consultation in June 2015. The whole process has led to a guideline which is much more in-keeping with international practice, as outlined in the position statement from the American Diabetes Association and European Association for the Study of Diabetes, updated in January 2015.
NG28 replaces the previous NICE clinical guideline (CG) 66, published in 2008 and the subsequent glycaemic update (CG87) which was published one year later. The technology assessments relating to liraglutide (TA203) and exenatide prolonged-release are also superseded by this document. This means that TAs for the three SGLT2 inhibitors remain extant.
The guideline contains recommendations for managing type 2 diabetes in adults, and focuses on patient education, dietary advice, managing cardiovascular risk, managing blood glucose levels, and identifying and managing long-term complications.
The advice on patient education is standard, with quality-assured structured education programmes mandated and regular audit of outcomes. I guess the only issue here (and, of course, it is a huge one) is whether local health economies have the funding to support this activity. Dietary advice and blood pressure management are similarly uncontentious with the vast majority of it being a re-stating of the recommendations in CG66 (from 2008). Lipid management is not dealt with and is left to CG181 published in July 2014; as an aside, I do regard this as contentious, given the focus on non-HDL cholesterol and targets based on pre-statin lipid levels. Both of these recommendations make routine audit of lipid management much more difficult.
Antiplatelet advice has changed to ‘Do not offer antiplatelet therapy (aspirin or clopidogrel) for adults with type 2 diabetes without cardiovascular disease’. Practitioners will need to decide how to manage those patients who are currently receiving aspirin, based on NICE’s previous advice (which recommended it for all T2DM patients over the age of 50 years, unless blood pressure was sub-optimally controlled). I would be inclined to leave things unchanged, given that the ASCEND Trial investigating the use of aspirin in ‘low risk’ patients with T2DM is due to complete in 2017.
Self-monitoring of blood glucose (SMBG) is generally discouraged in NG28 but by the time the various caveats (including DVLA requirements) are taken into account, there will be few patients for whom SMBG is completely excluded.
By far the most controversial areas of the drafts of this guideline involved blood glucose management and some of these remain (although they are greatly tempered). Targets for HbA1c are problematic. Despite widespread evidence of poor achievement of HbA1c targets in the UK (attributed to ‘clinical inertia’), NG28 recommends that levels for treatment escalation (58mmol/mol) are higher than the target for treatment (53mmol/mol). This ‘treat-to-failure’ approach is unlikely to promote better overall control.
The controversies over drug therapy for blood glucose control have largely receded following the down-playing of repaglinide and the formal inclusion of SGLT2 inhibitors into the treatment algorithm (which is likely to be the most widely read page of the entire document). DPP-4 inhibitors are now placed at the top of the lists of first and second-line intensification steps (and for monotherapy in metformin-intolerant patients) and modified-release metformin is included as an option.
The place of GLP-1 receptor agonists has diminished somewhat in NG28 in that they are now only an option when triple oral therapy including metformin has failed and they are not included in the metformin-intolerant algorithm at all. As before, there is a BMI threshold for GLP-1RA initiation (introduced on the basis of cost, rather than clinical evidence) and stopping rules apply which are made up of both HbA1c (11mmol/mol) and weight (3%) reductions. At least the combination of GLP-1RA and insulin is recognised (in a specialist environment) and the 1.2mg limit on liraglutide seems to have disappeared.
The advice on insulin is necessarily vague such as ‘offer NPH insulin injected once or twice daily according to need’ and wouldn’t encourage inexperienced professionals to embark on this therapy (probably a good thing). The premix advice doesn’t seem to have any evidence base behind it (e.g. a higher HbA1c of 75 mmol/mol promoting its use) and it is unclear why NG28 would imagine that any patient would prefer not to inject immediately before a meal when the option is doing so 30 minutes before.
Overall NG28 is to be welcomed and the challenge will be to get clinicians and patients to follow it in a way that prevailing high levels of HbA1c in the UK indicate was not the case for CG87 (which essentially advised the same targets). Another positive is the commitment of NICE to allow for more frequent review and update of the guideline since the pace of change in diabetes therapies is so rapid.
Professor Steve Bain