T2DM brief epidemiology
Almost 4.6m people in the UK and 30m Americans are living with diabetes: 90% of whom have T2DM. It is estimated that 12.3m people in the UK and some 70m in the US are considered pre-diabetic, which is when you have high blood glucose levels, but not high enough to be diagnosed with diabetes. The first WHO Global report on diabetes published in 2016 suggests that 422m adults (1 in 11) worldwide are living with the condition, which has quadrupled over the past three decades. The International Diabetes Federation (IDF) estimates that this figure will rise to 642m by 2040. A further challenge is the undiagnosed. A December 2017 paper in Nature Reviews: Endocrinology suggests 46% of all cases of diabetes globally are undiagnosed and therefore at enhanced risk of complications. Until complications develop, most T2DM patients are managed within primary care, which constitutes a significant part of general practice activity. International data suggest that medical costs for people with diabetes are two to threefold greater than the average for people without diabetes.
T2DM treated but not cured
The most common therapy for T2DM patients who are overweight is metformin, which is usually prescribed when diet and exercise alone have not been enough to control your blood glucose levels. Metformin reduces the amount of sugar your liver releases into your blood and also makes your body respond better to insulin. Insulin is a hormone produced by your pancreas that allows your body to use sugar from carbohydrates in food that you eat for energy or to store glucose for future use. The hormone helps to keep your blood sugar levels from getting too high (hyperglycaemia) or too low (hypoglycaemia). Metformin does not cure T2DM and does not get rid of your glucose, but simply transfers your excess sugar from your blood to your liver. When your liver rejects your excess sugar, the medicine passes the glucose onto other organs: kidneys, nerves, eyes and heart. Much of your excess sugar gets turned into fat and hence you become overweight or obese. T2DM has long been understood to progress despite glucose-lowering therapy, with 50% of patients requiring insulin therapy within 10 years. This seemingly inexorable deterioration in control has been interpreted to mean that T2DM is treatable but not curable. Research briefly described in this Commentary suggests that T2DM can be beaten into ‘remission’, but it requires losing a lot of weight and keeping it off.
Over the past decade a series of studies, led by Roy Taylor, Professor of Medicine and Metabolism at the University of Newcastle, England and colleagues from Glasgow University have explored the notion that losing weight could be the solution for controlling T2DM and lowering the risk of debilitating and costly complications.
Findings of a study in the December 2017 edition of the Lancet, suggested that nearly 50% of people living with T2DM who had participated in a low-calorie liquid diet of about 800 calories a day for three to five months had lost weight and had reverted to a non-T2DM state. The study was comprised of 298 adults between 20 and 65 who had been diagnosed with T2DM within the past six years drawn from 49 primary care practices in Scotland and Tyneside in England. Half of the practices put their patients on the low-calorie diet, while the rest were in a control group and received the standard of care of anti-diabetic medicines to manage their blood glucose levels. About 46% of 149 individuals with T2DM who followed a weight loss regimen achieved ‘remission’, which the study defined as a HbA1c of less than 6.5% after one year. Only 4% of the control group managed to achieve ‘remission’. ‘Remission’ rather than ‘cure’ was used to describe the reversal of T2DM because if patients put weight back on, they may become diabetic again. Results improved according to the amount of weight lost: 86% of those who lost more than 33 pounds attained remission, while 57% of those who lost 22 to 33 pounds reached that goal.
Another paper by Taylor and his colleagues published in the October 2018 edition of Cell Metabolism, examined reasons why substantial weight loss - (15kg) in some patients - produces T2DM remission in which all signs and symptoms of the condition disappear, while in other patients it does not. Using detailed metabolic tests and specially developed MRI scans, Taylor observed that fat levels in the blood, pancreas and liver were abnormally high in people with T2DM. But after following an intensive weight loss regimen, all participants in the study were able to lower their fat levels. As fat decreased inside the liver and the pancreas, some participants also experienced improved functioning of their pancreatic beta cells, which store and release insulin, controls the level of sugar in their blood and facilitates glucose to pass into their cells as a source of energy. The likelihood of regaining normal glucose control depends on the ability of the beta cells to recover. But, losing less than 1gm of fat from your pancreas through diet can re-start your normal production of insulin and thereby reverse T2DM.
“The good news for people with T2DM is that our work shows that you are likely to be able to reverse T2DM by moving that all important tiny amount of fat out of your pancreas. At present, this can only be done through substantial weight loss,” says Taylor.
While a significant proportion of participants in Taylor’s study responded to the weight loss program and achieved T2DM remission, others did not. To better understand this, researchers focused on 29 participants who achieved remission after dieting and 16 who dieted but continued to have T2DM. Taylor and his colleagues observed that people who were unable to restart normal insulin production had lived with T2DM for a longer time than those that could. Individuals who had lived with T2DM for an average of 3.8 years could not correct their condition through weight loss, while those who had the condition for an average of 2.7 years were able to regain normal blood sugar control.
“Many [patients] have described to me how embarking on the low-calorie diet has been the only option to prevent what they thought - or had been told - was an inevitable decline into further medication and further ill health because of their diabetes. By studying the underlying mechanisms, we have been able to demonstrate the simplicity of T2DM and show that it is a potentially reversible condition. but commencing successful major weight loss should be started as early as possible,” says Taylor.
Click on Newcastle University to find out more information about reversing T2DM by weight loss.
Bridging the gap between science and policy
Taylor and his colleagues describe their research findings as “very exciting” because “they could revolutionise the way T2DM is treated”, but caution that a series of management issues will need to be overcome before their therapy becomes common practice. This includes, (i) familiarizing primary care doctors and T2DM patients with the treatment regimen, (ii) establishing a generally accepted standard for what actually constitutes “remission”. Taylor and colleagues recommend “remission” to be when a patient has not taken diabetes medicines for at least two months and then has two consecutive HbA1c levels, taken two months apart, which are less than 6.5%. Researchers also recommend that data on T2DM reversal rates should be routinely collected, stored, analysed and reported.
Notwithstanding, the ‘elephant in the room’ is the vast extent of diabesity, the eye-watering rate at which it is growing and the general ineffectiveness of policy makers and prevent programs to dent the burden. Research findings presented at the 2018 European Congress on Obesity in Vienna emphasize the magnitude of the problem. If current trends continue, almost a quarter (22%) of the world’s population will be obese by 2045 (up from 14% in 2017), and 12% will have T2DM (up from 9% in 2017). Findings also suggest that in order to prevent the prevalence of T2DM from going above 10% by 2045, global obesity levels must be reduced by 25%. The problem is no less grave at the national level. For example, in the UK, if current trends continue obesity will rise from 32% today to 48% in 2045, while diabetes levels will rise from 10.2% to 12.6%, a 28% rise. This is unsustainable. Here’s the challenge for policy makers.
To stabilise UK diabetes rates over the next 25 years at 10%, which is high and extremely costly, obesity prevalence must fall from 32% to 24%. Similarly, in the US, if current trends continue over the next 25 years, then to keep diabetes rates stable over the same period, obesity in the US would have to be reduced by 10%: from 38% today to 28%.
Taylor and his colleagues have delivered a simple and cheap solution to one of the biggest burdens of the 21st century. But unless there is effective strategy to implement this solution the four decades of research undertaken by Taylor and his colleagues will be wasted. Previous Commentaries have described the vast and crippling burden of diabesity and the failure of well-funded programs to make any significant dent in this vast and escalating burden, which is out of control. We have suggested, this is partly because, at the operational level, programs have tended to be predicated upon inappropriate, old fashioned, 20th century organizational methods and technology and focused on “activities” rather than “outcomes”. At a policy level, government agencies have systematically failed to slow the rise of processed food becoming the “new tobacco”. Most UK endeavours to reduce the burden of diabesity are like putting up an umbrella to fend off a tsunami. This must change if we are to harness and effectively deploy the research findings of Professor Taylor et al.