There’s much to be said for being a friendly, sociable person but you might be surprised to know that a cheery disposition could help protect you from a heart attack.
That’s according to new research published in the European Journal of Cardiovascular Nursing. The study, from the University of Tennessee, found those with a “sarcastic, cynical, resentful, impatient or irritable” personality were more likely to die if they had a second heart attack.
The study found that ‘hostile’ personality traits were an independent predictor for heart attack mortality even after adjusting for other factors such as sex, age, education, marital status, diabetes, high blood pressure, and smoking.
In short, being grumpy doesn’t make you more likely to have further heart attacks after already having one, but it does make you more likely to die from them.
"Hostility has been linked with cardiovascular disease since the 1950s, but we still don't fully understand why,” said study author Dr. Tracey Vitori. “Our study shows that hostility is a common trait in heart attack survivors and is associated with poor outcomes. More research is needed on how this characteristic affects the body.”
But this isn’t the only way your personality might have an effect on your overall health. Here are a few others…
Extroverts have stronger immune systems
According to a 2015 study from the University of Nottingham, people who are outgoing tend to have higher levels of inflammation, an immune response which helps the body heal more quickly from injuries and fight off infection. Tests showed the genes responsible for inflammation worked 17 per cent more in people who were considered extroverts on a personality quiz than in those who were more introverted.
The downside of this, however, is that inflammation has been linked to various negative side-effects such as diabetes, atherosclerosis and cancer so it may not be an entirely good thing, especially later in life.
One theory as to why this effect is observed is not that the personality informs the immune response, but that the immune response informs the personality. Perhaps the underlying weakness of the immune system is what makes introverts more cautious and risk-averse.
Optimists have better health and a lower risk of death
For decades studies have been published showing that looking on the bright side is good for your health. In a 2014 study of middle-aged patients who’d undergone coronary artery bypass surgery, for example, optimists were half as likely to be readmitted to hospital and reported lower pain intensity from the surgery.
All the way back in 2000, a Finnish study found pessimists are more at risk of high blood pressure than those with a more positive outlook, even after accounting for other factors such as smoking, obesity, physical inactivity, and alcohol abuse.
In addition, a 2006 study found optimists were less likely to exhibit viral symptoms than pessimists when exposed to the same illness.
The list of good health outcomes from positivity goes on: those who laugh more boost energy consumption and heart-rate by 10-20 per cent, for example, while older adults who are more positive are more likely to stay healthy and live independently. There are numerous theories. The first being that healthier people are more likely to be positive than those who are more prone to illness. However, it might be that optimists are more likely to live a healthy lifestyle and form strong support networks, which has been linked to good health. It might also be that optimistic people produce less of the stress hormone cortisol, which reduced inflammation.
Cynics and introverts are more likely to suffer from dementia
That’s according to a 2014 study from Sweden which found those who are distrustful of others were three times more likely to suffer dementia than others who weren’t so cynical.
“It could be because people with a high degree of cynical mistrust of other people are less likely to take part in social events than people with more optimistic types of personality,” said the study’s lead author Anna-Maija Tolppanen. “We know that social isolation increases the risk of dementia.”
Being socially active, engaging with others, and even just having conversations have all been shown to have a protective effect against dementia, so it stands to reason those with a more misanthropic disposition would be more at risk.
Another study in 2012 found that depressive or hostile personality traits were linked to a decrease in intelligence in older age.