Why drugs don’t work

STATINS are taken by millions of Britons, yet nearly half of patients are resistant to their cholesterol-lowering effects.  Now scientists think they have pinpointed the cause - a protein called resistin.

A team from McMaster University in Canada said their research suggests high levels of resistin in the blood could stop statins from working effectively.

The protein is secreted by fat tissue and causes high levels of ‘bad’ cholesterol also known as low-density lipoprotein or LDL. This accumulates in the arteries and increases the risk of heart disease.

The researchers found that resistin also degrades LDL receptors in the liver. As a result, the liver is less able to clear ‘bad’ cholesterol from the body.

It not only causes high levels of LDL, but also counteracts the beneficial effects of statins - the main drug used to tackle the problem. Dr Shirya Rashid, senior author of the study said: ‘The bigger implication of our results is that high blood resistin levels may be the cause of the inability of statins to lower patients’ LDL cholesterol,’ said Dr Rashid. She noted that a staggering 40 per cent of people taking statins are resistant to their impact on lowering blood LDL. However, she believes their discovery could lead to revolutionary new therapeutic drugs, especially those that target and inhibit resistin and thereby increase the effectiveness of statins.

Heart and Stroke Foundation spokesperson Dr Beth Abramson said: ‘The possibilities for improved therapy for the causes of cardiovascular disease are very important.’  Dr Abramson noted that the research reconfirms the importance of maintaining a healthy weight and cholesterol level, two critical factors in the prevention of heart disease.

High blood cholesterol is a major risk factor for heart disease and stroke. It can lead to a build-up of plaque in the artery walls and narrowing of the arteries, causing a condition called atherosclerosis which can make it more difficult for blood to flow through the heart and body.

Being overweight also increases the likelihood of high blood pressure and diabetes, compounding the risks of heart disease and stroke. Dr Abramson added: ‘Fortunately, we know a great deal about heart disease prevention and how to reverse some of the risks.’

She urged people to maintain their heart health through regular visits to their doctor, monitoring their weight and waist size, eating a variety of nutritious, low-fat foods and being physically active, adding: ‘It’s equally important to take your medications as directed by your physician to help further reduce risks.’

The findings were presented at the Canadian Cardiovascular Congress