There was some recovery after people stopped working antisocial shifts, but it took five years to return to normal.<\/p>\n
Experts say the findings could be important in dementia, as many patients have disrupted sleep.<\/p>\n
The body’s internal clock is designed for us to be active in the day and asleep at night.<\/p>\n
The damaging effects on the body of working against the body clock, from breast cancer to obesity, are well known.<\/p>\n
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<\/div>\nNow a team at the University of Swansea and the University of Toulouse has shown an impact on the mind as well.<\/p>\n
Three thousand people in France performed tests of memory, speed of thought and wider cognitive ability.<\/p>\n
The brain naturally declines as we age, but the researchers said working antisocial shifts accelerated the process.<\/p>\n
Those with more than 10 years of shift work under their belts had the same results as someone six and a half years older.<\/p>\n
The good news is that when people in the study quit shift work, their brains did recover. Even if it took five years.<\/p>\n
‘Substantial decline’<\/span><\/p>\n Dr Philip Tucker, part of the research team in Swansea, told the BBC: “It was quite a substantial decline in brain function, it is likely that when people trying to undertake complex cognitive tasks then they might make more mistakes and slip-ups, maybe one in 100 makes a mistake with a very large consequence, but it’s hard to say how big a difference it would make in day-to-day life.”<\/p>\n He said he would not do night shifts “if I could possibly help it” but they were a “necessary evil” that society could not do without.<\/p>\n “There are ways to mitigate the effects in the way you design work schedules and regular medical check-ups… should include cognitive performance tests to look for danger signs,” he added.<\/p>\n Dr Michael Hastings, from the UK Medical Research Council’s Laboratory of Molecular Biology, told the BBC: “The reversibility is a really exciting finding because no-one else has shown it and no matter how compromised a person may be there’s always hope of recovery.”<\/p>\n He said the findings may have important consequences in dementia, which is known to damage sleeping patterns in a similar way to shift work.<\/p>\n “If you can keep the sleep-wake cycle as solid as possible you’re unlikely to reverse neurodegeneration, but you can ameliorate one of the consequences.<\/p>\n “In nursing homes one thing you can do to help is to set a very clear daily routine to encourage a sensible 24-hour pattern of activity; it needs bright lights in the day, resting at night and appropriate medication such as melatonin before bed.”<\/p>\n Prof Derk-Jan Dijk, from the Surrey Sleep Centre, cautioned that retired shift workers still had lower sleep quality than people who had never done nights.<\/p>\n “So some of these effects may not be so readily or rapidly reversed.”<\/p>\n He added: “We now accept that shift work may not be good for your physical health, but this shows your brain function is affected, and I think that finding will surprise many people.”<\/p>\n![\"Eating](\"http:\/\/news.bbcimg.co.uk\/media\/images\/76462000\/jpg\/_76462959_480311049.jpg\")
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