First evidential study of the impact of weight-loss surgery on long-term microvascular complications associated with long-term type-2 diabetes.
The case for more aggressive treatment of pre-diabetes has received a significant boost following results of a major new study, carried out by AstraZeneca scientists in collaboration with Swedish clinicians leading the Swedish Obese Subject (SOS) study. The results show, for the first time, that early intervention in prediabetic obese patients can prevent serious long-term microvascular complications affecting the eyes, nerves and kidneys.
The research, published this week in the leading diabetes journal, Lancet Diabetes and Endocrinology, calls into question current recommendations on when treatment should start for patients with raised blood glucose levels.
“Our study is a small brick in building the case for redefining the cut-off for when to start treating patients. But it is an important paper as, right now, it is the only study in which this analysis has been done,” says Professor Björn Carlsson, from Innovative Medicines and Early Development Biotech Unit at AstraZeneca.
The SOS study in over 4,000 obese patients investigated the impact of weight loss surgery on the microvascular complications typically seen in patients with long-term type-2 diabetes. This is a condition whose prevalence has doubled during the last 30 years, due in part to rising levels of obesity.1
The SOS results revealed that surgical intervention reduced microvascular complications by nearly 50% compared to standard non-surgical care, during average follow-up of 19 years. The treatment benefit was greatest for patients with pre-diabetes (as shown by blood glucose levels at study entry), compared with those with established diabetes, screen-detected diabetes, and normal glucose status. The effect was independent of whether patients with pre-diabetes went on to develop diabetes during follow up.
Professor Carlsson points out that some experts, including the American Diabetes Association, already advocate treatment for some patients with pre-diabetes.
“Pre-diabetes is a condition that should be treated more aggressively rather than waiting until glucose levels reach the diabetic range, particularly among pre-diabetic patients already showing signs of microvascular disease,” he says.
The study authors explain that pre-diabetes and diabetes represent different stages of the same progressive disease. They are only distinguished by diagnostic criteria that may be considered an arbitrary cut-off, but currently determine the level of care and medical intervention that patients receive. The glycaemic cut-off is based on the risk for microvascular complications assessed in cross-sectional, non-interventional studies.
In contrast, the SOS study is a longitudinal, interventional study whose findings may help to redefine when to intervene with medical treatment for patients with pre-diabetes.
Through its cardiovascular and metabolic disease research programme, AstraZeneca aims to accelerate achievement of treatment goals and reduction of complications for patients at all stages of diabetes progression. AstraZeneca Gothenburg, one of the company’s three global, strategic R&D centres, carries out collaborative research with clinicians and scientists across many leading hospitals and research institutions in Sweden, the Nordic region and beyond.
1. Global Report on Diabetes. World Health Organization, Geneva, 2016.