People who look younger than their actual age have a longer life expectancy than those who look their age, according to Danish scientists.

To reach this conclusion, Kaare Christensen of the University of Southern Denmark and colleagues asked nurses, teachers-in-training and peers to guess the age of 1,826 pairs of twins from their photos.

The twins were at least 70 years old when they were photographed.
 
For all 3 assessor groups, perceived age of the twins was associated with their survival, even after adjustment for chronological age, gender, pre-existing medical conditions, cognitive abilities and socioeconomic status.

Furthermore, the bigger the difference in perceived age within the pair, the more likely it became that the older looking twin died first.

The authors even provided a possible physiological explanation for their finding: key pieces of cellular DNA known as telomeres, which predict the ability of cells to replicate, were also linked to perceived age, the group found.

Shorter telomeres are associated with more rapid ageing, and the scientists found that people who looked younger had longer telomeres.

Christensen suggested to the BBC that people who have had a tougher life are more likely to die early – and that their life is reflected in their face.

“It’s probably a combination of genes plus environment over a lifetime that are important,” said UK professor Tim Spector, who has been doing similar research on twins. “We are also finding this in our study.”

The write-up is in the British Medical Journal.

A meta-analysis performed by Italian scientists has shown that reducing salt intake by half in Westernized countries can reduce strokes by 23%, which amounts to about 1.25 million deaths, and reduce cardiovascular disease by 17% which amounts to nearly 3 million additional deaths per year.

Americans consume about 10 grams (or 2 teaspoons) of salt per day.

The  World Health Organization recommends that dietary salt intake should be half that. The US Department of Agriculture recommends just under 6 grams per day.

To reach their astounding conclusions, Pasquale Strazzullo and colleagues at the University of Naples pooled data from 13 prospective studies published between 1966 and 2008. The analysis covered 177,000 subjects who sustained more than 11,000 strokes or cardiovascular events.

The extra power of the meta-analysis proved decisive in reaching the positive conclusions, since only 9 showed a direct positive link between sodium intake and the adverse events (of which only 4 reached statistical significance). Three  actually showed a non-significant inverse relationship.

Studies featuring longer periods of follow-up appeared to strengthen the relationship between salt intake and stroke, although this was not the case for cardiovascular events.

The findings were not impacted by age, sex, and hypertension status.

In an accompanying editorial, Lawrence Appel of Johns Hopkins hailed the study as a “useful and welcome addition” to the confusing literature on the subject.

“At a minimum, Strazzullo and colleagues’ analyses should dispel any residual belief that salt reduction might be harmful (a canard resulting from misinterpretation of studies, often with flawed analyses),” Appel wrote.

Appel probably had in mind long-standing efforts by the food industry to oppose tougher public health policies on dietary salt intake, which have been largely successful because the above-mentioned studies had muddied the waters so completely.

The write-up is in the British Medical Journal.

Contrary to FDA warnings on the matter, a UK  study has found “no clear evidence” to support the claim that the cigarette cessation drug Chantix increases the risk of suicidal thoughts and suicide.

To reach these conclusions, David Gunnell and colleagues at the University of Bristol reviewed the records of 80,660 men and women aged 18-95 years that had received a smoking cessation product (Chantix, Zyban or nicotine replacement therapy) between September 2006 and May 2008.

The scientists found 166 episodes of nonfatal self-harm and 2 suicides — both occurring in patients receiving nicotine replacement therapy. An additional 37 subjects reported having suicidal thoughts.

Chantix and Zyban did increase the risk of such phenomena by 12% and 17% compared with nicotine replacement products in the study, but this difference did not achieve statistical significance. The authors were left to conclude there was no clear evidence that Chantix was associated with an increased risk.

The limited study power “means we cannot rule out either a halving or a twofold increase in risk,” according to the authors.

Chantix also did not appear to increase the risk of depression or suicidal thoughts, confirming a report last March.

The FDA issued black box warnings for both Chantix and Zyban last July, and regulatory agencies around the world followed suit after adverse event reports raised the possibility of such a relationship.

The authors noted that smokers have a nearly threefold increased risk of suicide, probably because people with psychiatric illnesses are far more likely to be smokers.

It’s possible, they said, that smoking “has a beneficial effect on psychiatric symptoms, such as anxiety, that may be lost with smoking cessation.”

The write-up is in the British Medical Journal.

Adolescents who act out in class are more likely to experience mental illness, alcohol abuse and both social and financial difficulties later in life, according to a study in the British Medical Journal. 

To reach this conclusion, Ian Colman and a team at the University of Alberta queried data involving all 3652 people born in the UK during a one-week period in 1946 using the Medical Research Council National Survey of Health and Development

In this cohort, teachers had documented “externalizing behavior” such as poor attention in class, disobedience, lying, truancy, tardiness, or poor response to discipline when they were 13 and 15 years old.

9.5% of the participants were classified with severe behavioral problems, and another 28.8% with mild problems.

Study investigators reassessed participants at ages 36, 43 and 53 for mental health, social, and economic outcomes.

It turned out that those with severe behavioral problems during adolescence were 30% more likely to experience symptoms of anxiety and depression, and twice as likely to experience financial difficulties later in life.

Those with at least mild conduct problems were 40% more likely to abuse alcohol and 2.3 times more likely to be involved with a pregnancy during adolescence.

When it came to dropping out of school, those with mild teen behavioral disturbances were more than twice as likely, and those with severe conduct problems were 4 times more likely.

Divorce was 50% and 70% more likely for those with mild and severe conduct problems in adolescence, and self-reported unhappy family life was 30% and 60% more common in those with mild and severe problems respectively. 

The findings held true in men and women and were not affected by educational level.

In the latest and by far the biggest buzz-producer on the subject, Christakis and Fowler concluded that happiness is contagious.  If your friends become happy, sooner or later you will too. 

Yea right.

Tell that to the 6 Yankee fans living in Boston in October, 2004 when their team experienced the greatest collapse in American sports history, at the hands of the dreaded Sawx no less.

Those few-and-far-between Yankee fans were immersed by a wave of collective happiness involving essentially everybody within a 200 mile radius. The celebration continued well after the Townies rolled to their first World Series victory in 86 years.

How happy were people in Boston? 60 year-old men wept openly and wished only that their fathers were still alive to share the joy. 40 year-olds wept too. They hoped their little ones would remember where they were when it happened.

Friends, family members, work associates, even the baristas and gas pumpers of those 6 Yankee fans got happy, but the emotion sure didn’t spread to those poor Yankee fans.

The Red Sox triumph was an epiphenomenon, a big, contextual event that out-explains the explanation given by Christakis and Fowler.

Subtle epiphenomena from upticks in the economy to a cool new teacher at middle school, to the release of a Harry Potter movie provide a more plausible explanation for Christakis and Fowler’s observations, even though the particular epiphenomena at work are unknown and unknowable.

Look, when the Sox won game 4 to cut the series deficit to 1-3, a handful of Sox fans became happy. At least we weren’t swept, those few fans reasoned.

A day later the Sox won game 5 and more people became happy.

When the Sox won their third in a row to tie the series, pandemonium reigned and that was dwarfed by the transcendent moment at the end of game 7.

The epiphenomenon of the Sox’ comeback explains how, over time more Bostonians got happy. Christakis and Fowler want you to believe instead that happiness is contagious. That’s buzz-worthy and actually plausible at first blush, but it is simply wrong and 6 Yankee fans living in Beantown will attest to that.

Happiness is contagious, or at least that’s how 2 scientists explain what they observed when they analyzed self-reported data on emotional well-being from the Framingham Heart Study.

In addition to their emotions, study participants had also identified family members, friends and employers participating the Study. The resulting 50,000 social ties enabled the scientists to map out a happiness grid.

They used it to track happiness as it ebbed and flowed among residents of the Massachusetts city.

They concluded in the British Medical Journal that happy people caused family members and friends but not coworkers to become happy and the impact extended out, albeit with decaying strength, to 3 degrees of separation (the friends of one’s friends’ friends). 

Surprisingly, happy people were 3 times more likely to cause close friends to become happy than their spouses.

“You would think that your emotional state would depend on your own choices and actions and experience,” Nicholas Christakis told the Washington Post.

But the study’s co-author claims his findings show that “it also depends on the choices and actions and experiences of other people, including people to whom you are not directly connected.”

“It’s a pathfinding article,” decorated psychologist Martin Seligman gushed to the Post.  The professor at the University of Pennsylvania added, “It’s totally original, and the findings are striking.”

“This now makes me feel so much more responsible that I know that when I come home in a bad mood I’m not only affecting my wife and son but my son’s best friend or my wife’s brother,” study co-author James Fowler told the New York Times.

Maybe, maybe not. A post appearing later today offers another way to interpret the data.

About half the US physicians polled in a recent survey regularly prescribe placebos and most believe the practice is ethical, according to a report in the British Medical Journal.

The placebo effect refers to perceived clinical improvement caused by an inert substance such as a sugar pill or salt water, or one that has no impact on the condition for which it is prescribed. Since the 1960s, many clinicians and ethicists have frowned on placebo therapy because it involves deception and thus disregards principles of informed consent and patient autonomy.  Others disagree, noting that placebos can be the most effective treatment for certain conditions, and they can be administered without deception.

In the BMJ study, scientists surveyed 600 internists and 600 rheumatologists they had randomly selected from the American Medical Association master files. 46-58% (depending upon how the question was worded) reported using placebos regularly. The most common placebos were over-the-counter analgesics (41%) and vitamins (38%). Thirteen percent used antibiotics and sedatives as placebos.

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