Daily Times

ISLAMABAD: Higher childhood intelligence is linked to a lower chance of dying before the age of 80.

The researchers, from the University of Edinburgh in Scotland, UK, report their findings in a paper published in the BMJ.

The report describes how higher scores on childhood IQ tests were linked to a lower lifetime risk of dying from known major causes, including heart disease, stroke, smoking-related cancer, digestive disease, external causes of death, respiratory diseases, and dementia.

For these diseases, the reductions in risk were largely similar for men and women. But the researchers also found that, in men only, a higher childhood IQ was linked to a lower risk of suicide.

The researchers say that the findings suggest that lifestyle – and smoking in particular – is an important factor in the link between childhood IQ and risk of death.

Previous studies have already suggested that people who score higher on intelligence tests tend to live longer, on average, than people with lower scores. However, most of these do not span the life course, or they only focus on particular groups.

As well as finding a link between higher childhood IQ and lower risk of dying before the age of 80, the researchers found that the amount of reduced risk varies by cause of death.

For instance, their analysis reveals that a higher score on childhood IQ tests is linked to a 24 percent lower risk of dying from stroke, a 25 percent lower risk of dying from coronary heart disease, and a 28 percent lower risk of dying from respiratory disease.

The team also found links between higher childhood IQ and lower risk of death from injury, dementia, digestive diseases, and smoking-related cancers such as lung and stomach cancer.

However, they found no evidence of a link between childhood IQ and death from cancers that are not related to smoking.

When they adjusted the results to take into account smoking and socioeconomic status, the researchers found that some of the links remained strong, suggesting that these factors do not fully explain the differences.

They suggest that future studies should now investigate the “cumulative load of such risk factors over the life course.”

Swedish researchers specialising in public health and population studies note that the Scottish study is “uniquely comprehensive” because it examines major causes of death and follows the participants to an age by which nearly half of them have died.

They draw attention to a section of the study report that looks at how increments in childhood intelligence relate to specific causes of death. They liken it to a drug trial that looks at the effect of different doses.

“The most obvious dose-response relations are those for cardiovascular disease, coronary heart disease, stroke, smoking-related cancer, and respiratory disease,” they note.

Although “injuries could also be added to this list”, they remark that, nevertheless, the study “tells us that lifestyle, and especially tobacco smoking, must be an important component in the effect of intelligence on differences in mortality.” They conclude: “It remains to be seen if this is the full story or if IQ signals something deeper, and possibly genetic, in its relation to longevity.”

Disturbed sleep: Insomnia, nightmares, and erratic sleep times could be indicators of worsening suicidal thoughts among young adults, a new study suggests.

Researchers found that young adults who experienced sleep disturbances were more likely to have suicidal thoughts over the subsequent three weeks, compared with young adults who slept well.

Lead author Rebecca Bernert, PhD, assistant professor of psychiatry and behavioral sciences at Stanford University in California, and colleagues recently reported their findings in the Journal of Clinical Psychiatry.

For one week, participants were required to wear an accelerometer on their wrist each night. This enabled the researchers to monitor their wrist movements, which previous research has shown is a reliable indicator of sleep-wake patterns.

The participants also completed questionnaires detailing the severity of insomnia, nightmares, depression, alcohol intake, and suicidal thoughts. Questionnaires were completed at study baseline, as well as 1 and 3 weeks after sleep monitoring.

Compared with participants who fell asleep and awoke at similar times each day, those who had greater variability in their sleep and wake times – particularly the former – were more likely to have suicidal thoughts 1 and 3 weeks later.

“Insomnia and nightmares beget more variability in when we are able to then fall asleep on subsequent nights, which speaks to the way in which insomnia develops,” notes Dr Bernert.

“Sleep is a barometer of our well-being, and directly impacts how we feel the next day,” she adds. “We believe poor sleep may fail to provide an emotional respite during times of distress, impacting how we regulate our mood, and thereby lowering the threshold for suicidal behaviors.”

Dr Bernert and team believe that insomnia, variability in sleep-wake times, and other sleep disturbances may be a predictor of suicidal thoughts among young adults – a population most commonly affected by suicide. As Dr Bernert says, sleep disturbances “may represent an important treatment target in suicide prevention”.

The team is already in the process of conducting two clinical trials, in which non-drug treatments for insomnia are being tested for their efficacy in preventing suicidal behaviors. “Compared to other risk factors for suicide, disturbed sleep is modifiable and highly treatable using brief, fast-acting interventions,” says Dr Bernert.

Rebecca Bernert, PhD said: “Because sleep is something we universally experience, and we may be more willing to openly talk about it relative to our mental health, we believe its study may represent an important opportunity for suicide prevention.”

Published in Daily Times, July 2^nd, 2017.