What is health? The importance of patient-centred outcomes

The World Health Organization (2005) defines the concept of health, stated in the preamble to its constitution, according to the following ideas and principles:

• Health is a state of complete physical, mental and social wellbeing, and not merely the absence of disease or infirmity.
• The enjoyment of the highest attainable standard of health is one of the fundamental rights of every human being, without distinction of race, religion, political belief, economic or social condition.

I am confident that the vast majority of healthcare professionals and the general public agree with these principles. This Digest provides summaries of a few important research outputs that consolidate the validity of our national and international guidelines for patients with diabetes (especially type 2 diabetes) by providing good evidence of patient-centred outcomes.

Physical function is often not measured in a clinical setting as an outcome for our patients. It is, therefore, reassuring to learn that the GLP-1 receptor agonist group of drugs result in a significant improvement in both the Short-Form 36 and Impact of Weight on Quality of Life-Lite scores (click here for the Digest). The data for other groups of drugs such as SGLT2 inhibitors and DPP-4 inhibitors was far less compelling, however.

Our patients with diabetes would also wish to have fewer diabetes complications. Dementia is often not regarded as a complication of diabetes, but this is belied by the study reported by Cho and colleagues, who retrospectively analysed data on 20 487 people with diabetes in South Korea over a 16-year period (click here for the Digest). An 11 mmol/mol increase in mean HbA_1c increased the risk of dementia by 43%. Furthermore, there was an almost 300% increased risk with poor glycaemic control (≥86 mmol/mol) in comparison to good glycaemic control (53 mmol/mol). From a patient education perspective, another way to interpret the data would be that every 11 mmol/mol (1.0%) increase in HbA_1c meant that dementia occurred just over a year earlier (381 days). A firm reminder that we should remain committed to long-term good glycaemia.

When it comes to cardiovascular outcomes, we can be assured from the network meta-analysis conducted by Shi et al (click here for the Digest). This monumental undertaking identified 816 randomised controlled trials with 471 038 participants. In terms of hard clinical outcomes, all-cause mortality was reduced by SGLT2 inhibitor and GLP-1 receptor agonist therapy. These agents also reduced cardiovascular mortality, non-fatal myocardial infarction, hospitalisation for heart failure and end-stage kidney disease. Finerenone also reduced the risk of end-stage kidney disease. Further real-world evidence for the role of SGLT2 inhibitors in renal protection is also demonstrated in the study by Forbes et al (click here for the Digest).

Body weight reduction is an important outcome in many patients, and Shi et al’s meta-analysis showed that the greatest reductions were observed with tirzepatide, followed by semaglutide and then other GLP-1 receptor agonist therapies. SGLT2 inhibitors and metformin were also weight-reducing, albeit less potent in this regard.

Clearly, then, the drugs work. However, we finish on a lifestyle factor. A prospective cohort study from the US shows that sugar-sweetened beverage consumption is associated with increased mortality in patients with type 2 diabetes (click here for the Digest). Over 285 967 person-years of follow-up, sugar-sweetened beverages were associated with a 20% increased risk of mortality 25%, whilst coffee consumption was associated with an 26% reduction.

So, settle down with a cup of coffee (unsweetened!), and enjoy the summaries!