Common virus that could raise the risk of diabetes
ACOMMOn type of herpes virus could increase your risk of developing type 2 diabetes, new research suggests. More than 4.9 million people in the uK have type 2, which occurs when the body is unable to regulate blood sugar levels. A further 13.6 million people are at risk of developing it because it is closely linked to obesity.
now researchers at Ludwig Maximilian university and Helmholtz Munich in Germany have found that the herpes virus can contribute to the development of the condition.
Their study followed previous research that suggested viruses (including rubella and hepatitis C) are associated with type 1 diabetes (an autoimmune disease not linked to obesity).
For the latest study, the researchers recruited more than 1,200 adults with normal blood sugar levels. The participants were tested for the eight known herpes viruses, including herpes simplex viruses 1 and 2 (HSV1 and HSV2, which cause cold sores and genital herpes, respectively), varicella-zoster virus (chickenpox and shingles), the epsteinBarr virus and cytomegalovirus (which is widespread and usually symptom-less but can cause flulike symptoms).
Cytomegalovirus (CMV) was very common, with 46 per cent of participants testing positive for antibodies, an indicator of past infection, while 11 per cent were positive for HSV2. Most also had antibodies to more than one type of herpes virus.
After seven years, 364 of the study participants developed prediabetes: those who tested positive for HSV2 at the start were 59 per cent more likely to develop prediabetes or diabetes than those without signs of a previous herpes infection.
Those infected with CMV were 33 per cent more likely to develop prediabetes or diabetes, reports the journal Diabetologia. The researchers did not find a link between type 2 and herpes viruses that cause chickenpox, cold sores or shingles.
Dr Tim Woelfle, a reader in neurology and lead author of the study, told Good Health: ‘I believe this is the first time research has focused on how herpes virus may trigger (pre)diabetes leading to type 2.
‘Our research is novel because we checked to see in advance whether our subjects had antibodies to different kinds of herpes viruses.
‘Many people do not know that they have been infected by one or more [types of] herpes virus, but it is extremely common. And while our study suggested that prediabetes incidence was primarily explained by age, BMI, cholesterol and fasting glucose, both HSV2 and
CMV added to the risk.’
Previous research has suggested that certain viruses may reduce the number of insulin-producing cells in the pancreas, or that viruses may switch off proteins that control how cells metabolise sugar into energy, which may explain how infection could be linked to type 2.
The researchers said it remains to be seen whether preventing herpes virus infections could reduce diabetes risk.
‘These results highlight the link between viruses and (pre)diabetes, and the need for more research evaluating public health viral prevention strategies, possibly including the development of effective vaccines against herpes viruses,’ said Dr Woelfle.
Commenting on the study, Dr Faye riley, research communications manager at Diabetes uK, said: ‘This study raises intriguing questions about how viral infection could play a role in risk of type 2 diabetes.
‘But despite these findings, the overall research picture is mixed, and it’s far too early to say if or how important herpes viruses could be.
‘For now, the best way to reduce your risk is by eating a healthy, balanced diet and getting regular physical activity.’
The possibility that certain viruses might also contribute to type 2 diabetes is ‘interesting’, adds Dr Adnan Sharif, a consultant nephrologist at Queen elizabeth Hospital in Birmingham.
‘With regards to the line between type 2 diabetes and the herpes virus, the new research is certainly a step forward in our understanding,’ he says.