vital signs
© Jessica Rinaldi / Reuters
Researchers have found that about 70 percent of healthy people who worry about developing illnesses may be increasing their risk of heart disease. Another study shows the placebo effect in drug studies can be so powerful as to affect the outcomes.

"We hypothesized that people with health anxiety would have reduced risk [of heart attack] because they would take better care of themselves," said lead author Dr. Line Iden Berge from the division of psychiatry at Sandviken University hospital in Bergen, Norway.

Instead, in the study of more than 7,000 people, conducted over 12 years, researchers found that those who were hypochondriacs or suffered from "health anxiety" at the start of the study were about 70 percent more likely to develop heart disease than those less anxious.

"The results suggest it's better, instead of worrying about what's going on with your body and running to the doctor of any physical health problem, to seek a proper diagnosis and help for the anxiety disorder," Berge said.

The study defined health anxiety as "characterized by persistent preoccupation of having or acquiring a serious illness, misattribution of bodily symptoms and urge to seek medical advice in the absence of physical pathology."

Study participants, who were all born between 1953 and 1957, filled in questionnaires about their health, lifestyle and educational attainment and had a physical check-up between 1997 and 1999.

Levels of health anxiety were assessed using a validated scale and the top 10 percent of the sample - 710 - were considered to have health anxiety. The heart health of all participants was tracked through to 2009.

During the monitoring period, 234, or 3.3 percent of the entire sample had a heart attack or angina attack. Among those displaying levels of high health anxiety, results were twice as high with 6 percent succumbing to heart disease.

Researchers knew a risk of heart disease is largely influenced by lifestyle in terms of diet, reduction in tobacco consumption and increased level of physical activity. Other studies had shown that anxiety can be a factor for increased risk, independent of others risks, but little was known about the correlation between those suffering from anxiety or hypochondria and the development of heart disease.

The study was published this month in the journal BMJ Open.

In a related story, as part of an investigation into how impressionable and powerful the human mind is, Erik Vance found that many drug studies fail clinical trials because "interpretations of the placebo effect was too high."

Since the 1960s, the US government requires all clinical trials to have a placebo, or inert, trial to determine whether a potential drug is effective or not.

"[This] so-called placebo control has become increasingly difficult to manage. For certain ailments, so many respond so strongly to placebo that it's impossible to tell if the drug being tested is working or not. And this can be disastrous for people desperate for new therapies," Vance wrote in the Washington Post.

For an example, Vance found that Clinicaltrials.gov registered 4,152 clinical trials in 2011 to investigate new pain treatments. Over the next few years, the Food and DrugAdministration only approved five new treatments.

A solution is being suggested that could be to remove participants from the trial who are more susceptible to placebo. Researchers have found a gene called COMT regulates levels of neurotransmitter dopamine, the reward and pleasure center of the brain.

The study found about one-quarter of the human population has the gene that can neutralize dopamine and responds poorly to a placebo, while half the population has a mixed response, and one-quarter respond well to placebos.

The discovery has led to the formation of a company, Biometheus, that could in time help screen out patients likely to respond to the placebo.

There are some dissenters, though. One of the concerns is that by specify eliminating drug trial subjects with COMT genes could mean the drug won't be approved for the population at large. Other concerns are the placebo effect is a "complex phenomena," and not the result of "simple traits."

Recently a research group at the Brigham and Women's Hospital in Boston identified more than 30 genes related to the placebo effect.