By John Naish
PUBLISHED: 14:32 EST, 16 April 2012 | UPDATED: 14:32 EST, 16 April 2012
The well-known phrase, ‘no pain, no gain’ is more true than we ever thought.
Every year we spend millions of pounds trying to save ourselves from feeling pain, be it a throbbing headache or the excruciating agony of acute illnesses such as heart attacks and angina.
But scientists are realising how the dreaded sensation actually plays a crucial role in keeping us alive, by setting off hidden healing processes when we suffer heart attacks, and preventing chronic diseases such as arthritis breaking out.
Their discoveries fly in the face of current medical wisdom, which over the past four decades has become convinced that pain always delays healing in patients, and therefore should be stopped with drugs whenever possible.
But in the 19th century, many doctors believed something completely different — that pain was crucial to the healing process. Now those Victorian medics may at last be proved right, in areas such as angina and heart attacks, and even diabetes and arthritis.
This month, British scientists have discovered that the intense pain suffered during a heart attack may actually be helping to save people’s lives. Blocking it with powerful drugs may worsen the victim’s chances of survival, according to the investigators at Bristol University.
They have found that during a heart attack, pain signals from cardiac nerves help to attract stem cells from bone marrow to repair damage, and restore blood flow after a clot has starved the heart of oxygen-carrying blood. The investigations were first done on mice, and then with human patients.
Professor Paolo Madeddu, who led the study, says heart attack patients are nowadays routinely given pain-killing morphine, but the drug may actually cut their chances of survival. This is because it seems to stop the body’s stem-cell repair system working by inhibiting the pain response that should spark it off.
‘The actual sensation of pain may be very important here,’ he says, ‘because it seems to cause the brain to start physiological processes that are involved in the repair mechanism.’
Dr Helene Wilson, research adviser at the British Heart Foundation, which funded the study, adds: ‘Pain is a very complicated process. It is not just the body’s way of warning you something is wrong. When we feel pain, it can also be a sign the body is doing what it can to fix the problem.’
The idea that pain may bring benefits is certainly not new. As the historian Martin Pernick points out in his book, A Calculus Of Suffering, many surgeons in the 19th century believed pain was a medicine in its own right.
No pain, no gain: A study showed that people who have no angina pain before a heart attack are almost twice as likely to die from the attack as those who had suffered angina (posed by model)
They believed it somehow warded off infections and death after surgery, so they refused to give patients anaesthesia. Instead, they left them screaming in agony as the surgeon’s blade cut into them.
This may sound barbaric, but recent research supports their case. A study by the Good Samaritan Hospital Heart Institute in Los Angeles showed that people who have no angina pain before a heart attack are almost twice as likely to die from the attack as those who had suffered angina.
The report, in the journal Circulation, suggested that each painful episode of angina may actually toughen the cardiac muscle, so it will survive a heart attack with less damage.
There may be other ways in which severe pain may keep us healthy. Researchers at the University of California at San Francisco have found that the agony of inflamed joints may be the body’s way of telling its most aggressive defenders: ‘Hold on, that’s enough — you’re hurting me’.
Swelling, mild fever and soreness are all signs our body has set off an inflammatory reaction in response to an infection or damage. If unchecked, these defences can cause serious harm to healthy tissue, which is what happens in chronic inflammatory diseases like arthritis. But how the defences know when to stop had long been a mystery.
‘People will always think of pain in a very negative way but understanding its purpose could make it easier to bear’
However, research by Dr Holly Strausbaugh published in the highly respected journal Nature Medicine has demonstrated that pain plays an important role in regulating the body’s inflammatory cycle.
Her studies have shown that when a joint is infected, the body sends armies of invader-fighting cells called neutrophils. These, says Dr Strausbaugh, ‘pack a real wallop’ in causing infection-fighting inflammation.
But when the nerves around the affected joint fire off pain signals, these electrical alarms prevent any more neutrophils from entering the inflamed area. In effect, the pain pulses tell the neutrophils to go away and thus prevent the over-reaction.
Dr Strausbaugh believes people whose joint injuries are insufficiently painful in the first place are at greater risk of developing chronic problems such as arthritis.
Rather than being banished, the neutrophils wreak havoc on the joints — and when serious chronic pain does set in, it is too late. The damage has been done.
The answer may involve laying off painkillers that could dampen the body’s ‘stop now’ signal to its infection-fighting forces.
People will always think of pain ‘in a very negative way’, says Dr Strausbaugh, but understanding its purpose could make it easier to bear.