Why Races Respond Differently To Heart Failure Treatment
Different races are responding to heart failure treatment drugs and this fact was remaining unexplained, but a new research now shows that the key is gene variant.
Heart failure sufferers have weakened hearts unable to pump blood properly. Later, heart grows bigger to be able to supply with blood. With the heart weakening more and more, lungs gather fluids, and patients become very difficult to breathe. Even a very small amount exercising and even walking becomes very difficult for patients.
Heart failure patients usually take about five and even more drugs to treat the condition. In addition to a bunch of drugs, patients also take beta blockers. The mission of beta blockers is to weaken heart's response to epinephrine and norepinephrine hormones. This gives some rest to heart and extends patient's live.
There was a surprising difference among the ways patients responded to beta blocking drugs. Researchers from Washington University and University of Maryland examined 375 black patients with heart failure and found that 40% of them have altered gene controlling nerve signal responses. These people are making their own, natural versions of beta blockers. They do not respond to the drugs and don't benefit of them at all. Researchers found that about 2% of white people also have the altered gene. This is a significant difference among races showing the need of examining genetic background of each patient before prescribing heart failure treatment.
The research also explains why some people are unable to exercise heavily. Those with altered gene variant are having their hearts beating faster and more intensively during exercising. This happens among the rest of people with the normal version of the gene. However, people with altered gene have beta blocker activated during exercising and this limits the frequency of heart beats and makes heavy exercising very tiring for heart.
The finding shows that those with the altered version of the gene may give up taking beta blocking drugs, because they have a natural version of it. However, these patients will still have to take some other drugs. Scientists see a perspective of developing new ways of heart failure treatment for those altered gene and to use the natural beta blockers as a base for developing improved drugs.
Researchers also mention that those with altered gene version still suffer from heart failure despite of beta blockers, because they get activated only after the condition is established. Besides, beta blockers only slow down the progression of the disease, but it doesn't cure the disease. Therefore, these patients may stop taking beta blocking drugs and avoid adverse side effects of the drug, but they will still need to take other medications.