Weight loss surgery may optimise treatment of type 2 diabetes in obese

First randomised controlled trial comparing weight loss surgery with conventional diabetes care to conventional diabetes care alone shows five times higher diabetes remission rates.1

Weight loss surgery for obese people recently diagnosed with type 2 diabetes should be considered as an early treatment option to optimise improvement in their diabetes, general health outcomes and quality of life.

This is according to a new Australian study from the Centre for Obesity Research and Education (CORE), Monash University, published today in the Journal of the American Medical Association (JAMA), focusing on the treatment of diabetes through laparoscopic adjustable gastric banding (LAGB) surgery in addition to conventional diabetes therapy (such as diet and lifestyle changes) compared to conventional diabetes therapy alone.

Head of Clinical Research, CORE, and principal study investigator, Associate Professor John Dixon, said this is the first published controlled trial to provide concrete evidence that intensive and sustained weight loss as achieved through LAGB may be a more effective first step in managing diabetes in obese patients than simple lifestyle changes.

“Obesity and type 2 diabetes are strongly linked, with almost half of those with type 2 diabetes also being obese.

“Weight control is probably the most important aspect of type 2 diabetes management and one of our key findings is that the greater the weight loss, the greater the remission rate of diabetes,” Associate Professor Dixon said.

The study conducted on 60 obese patients (BMI >30 and <40) with newly diagnosed type 2 diabetes (within two years of trial recruitment), shows that after two years, obese patients with type 2 diabetes treated with LAGB surgery had a five times higher remission rate of their diabetes, a four times higher reduction of their blood sugar levels as well as a higher reduction of associated disorders including elevated blood pressure and cholesterol.

Diabetes remission was achieved by 73 per cent of LAGB surgery participants compared to 13 per cent of conventional diabetes care alone participants.

LAGB surgery also resulted in greater average body weight loss of 20.0 per cent compared to an average body weight loss of 1.4 per cent with the conventional diabetes care alone.

Blood glucose levels improved to within normal limits in 80 per cent of LAGB surgery participants compared to 20 per cent of people treated with conventional diabetes care.

The average BMI of LAGB participants also dropped from 36.9 to 29.5, whereas that of the conventional diabetes care participants dropped from 37.1 to 36.6.

Head of the Centre for Bariatric Surgery, Melbourne, and co-author of the study, Professor Paul O’Brien, said bariatric surgery guidelines typically include only people with a BMI greater than 35 who have type 2 diabetes as an associated health risk.

“Observational studies have shown that early and intensive treatment of type 2 diabetes improves health outcomes.

“Currently available lifestyle and weight loss medications provide only small to modest levels of weight loss and this is compounded by the fact that patients with diabetes find it more difficult to lose weight than those without diabetes,” Professor O’Brien said.

“In this study we found the effects of surgically induced weight loss were just as beneficial for participants with a BMI of 30–35 as they were for those with a BMI of 35–40.

“Even people who are in the lower obesity ranges can benefit from earlier intensive treatment and guidelines may need to change to reflect LAGB as a serious option if not routine,” said Professor O’Brien.

Further to the diabetes remission and improvement of associated health conditions, the study showed a greater reduction in the use of diabetes and non-diabetes medications including blood pressure-lowering and lipid-lowering medications in the LAGB surgery participants compared to the conventional diabetes care participants.

Among the LAGB surgery treatment group was 51 year old Domenic, who has now sustained diabetes reversal for 15 months following study completion and no longer uses his diabetes or blood pressure medications.

“Controlling my diabetes was challenging and when first diagnosed my focus was on watching my diet and medication and the impact of weight loss was never really stressed to me,” Domenic said.

“Once I was randomised into the surgical treatment group, as my weight dropped so did my blood glucose levels. I now maintain a healthy 71 kg and I’m still in remission.”

Source

1. Dixon JB, O’Brien PE, Playfair J, Chapman L, Schacter LM, Skinner S, Proietto J, Bailey M, Anderson M. Adjustable gastric banding and conventional therapy for type 2 diabetes – a randomised trial. JAMA 2008; 299 (3): 316-23.