August 15, 2017

expert reaction to study looking at obesity, metabolic health and coronary heart disease

Publishing in European Heart Journal, researchers looked at the ‘metabolically healthy obesity’ hypothesis in a large European prospective study. They reported that irrespective of BMI, those classed as ‘metabolically unhealthy’ had a higher risk of coronary heart disease. They also reported that those who were overweight and obese had a higher risk of coronary heart disease, irrespective of their metabolic health.

Prof Nick Finer, Honorary Clinical Professor, National Centre for Cardiovascular Prevention and Outcomes, UCL, said:

“This is an important paper that directly refutes the concept that it is OK to be overweight or obese provided that you do not have any metabolic risk factors such as abnormal cholesterol, lipid, glucose or diabetes, or high blood pressure (the so-called metabolic syndrome).

“In more than half a million people over 8 European countries, the authors found the expected increase in risk of coronary heart disease (such as angina or heart attack) in relation to both unhealthy normal weight people as well as unhealthy overweight and obese people, but more importantly also in ‘healthy’ overweight or obese people without these metabolic risk factors.

“A strength of the study (apart from its size, rigour and 12-year follow-up) was that information on physical activity, smoking, diet and social status could be adjusted for.  The authors final conclusion, “Population-wide prevention and treatment of obesity is therefore warranted, regardless of metabolic health”, is fully justified and supports the ever-pressing need for governments, local authorities, public health bodies, and individuals to seriously address the issues leading to our current levels of overweight and obesity.”

Prof Metin Avkiran, Associate Medical Director, British Heart Foundation, said:

“Coronary heart disease – the cause of heart attacks and angina – is the UK’s single biggest killer. But there are steps you can take to lower your risk.

“This study provides robust evidence that there is no such thing as ‘healthy obesity’.  It shows that being obese increases a person’s risk of developing heart disease, even if they are otherwise healthy.

“BHF-funded researchers are now looking to understand exactly how obesity leads to heart attacks.

“The take-home message here is that maintaining a healthy body weight is a key step towards maintaining a healthy heart.”

Dr Amitava Banerjee, Senior Clinical Lecturer in Clinical Data Science and Honorary Consultant Cardiologist, UCL, said:

“This is an important, high-quality study which looked at the association between being overweight or obese and the future risk of coronary heart disease.  In addition, the study looked at whether being ‘metabolically healthy’ (in terms of cholesterol, blood glucose, blood pressure) reduced the risk of heart disease in these individuals.  It is high quality because it recruited across European countries, was prospective and had good data on risk factors and the outcome (heart disease).

“Compared with metabolically healthy, normal weight people, there was double the risk of heart disease in ‘metabolically unhealthy’ people, regardless of whether they were normal weight, overweight or obese.  There was increased risk of heart disease associated with increased body mass index (BMI) from normal weight to overweight to obese individuals.  There are two implications.  First, this is strongly against the possibility of being obese and metabolically healthy.  Second, heart disease risk increases with increasing weight but also increases as the risk factors for heart disease increase (e.g. blood pressure), even in normal weight individuals.  The findings show that we need to view health holistically, including trying to maintain a healthy weight as one (among several) of the risk factors for heart disease.”

* ‘Separate and combined associations of obesity and metabolic health with coronary heart disease: a pan-European case-cohort analysis’ by Camille Lassale et al. was published in the European Heart Journal on Tuesday 15 August 2017.

Declared interests

Prof Nick Finer: “Prof Finer declares that he is employed by Novo Nordisk, a manufacturer of diabetes and weight loss medications.”

Prof Metin Avkiran: the British Heart Foundation part-funded this research.

Dr Amitava Banerjee: “No conflicts of interest.”