Possible link between sleep problems and Alzheimer's uncovered

Researchers have warned that those suffering from breathing difficulties during the night may be experiencing early signs of Alzeimer's disease. Although it is unknown what exactly the link between sleep-disordered breathing (SDB) and Alzeihmer's is, evidence suggests that some people who suffer from this particular disorder may already have developed pre-symptomatic dementia. The most common of these SDB's is obstructive sleep apnea, affecting around four per cent of middle-aged men and two per cent of middle-aged window. This particular disorder results in heavy snoring, and sleep being repeatedly interrupted. Research leader Ricardo Osorio of the New York University of Medicine, said: "We know that about ten to 20 per cent of middle-aged adults in the United States have SDB and that the number jumps dramatically in those over the age of 65. We don't know why it becomes so prevalent but one factor may be that some of these patients are in the earliest pre-clinical stages of AD (Alzheimer's disease)." 68 men and women with no previous evidence of dementia took part in the study, with around half found to have mild SDB and quarter had a moderate-to-severe form of the disorder. The volunteers also had brain scans and spinal fluid tests in an attempt to identify any biochemical signs of Alzheimer's. These biomarkers were only found among lean patients with SDB, although Dr Osorio is not clear which condition came first, the SDB or Alzheimer's. "It's really a chicken and egg story," he said. "Our study did not determine the direction of causality, and, in fact, didn't uncover a significant association between the two, until we broke out the data on lean and obese patients."