Here's a twist to the typical story about sleep apnea you don't see every day. A prominent sleep researcher in Israel discovered that elderly people with mild to moderate obstructive sleep apnea where less likely to die than their counterparts who didn't have sleep apnea. Their explanation is that years of hypoxia promoted increased collateral blood supply, meaning that the heart developed blood vessels that bypassed blockages. This explanation was supported by a recent German study which found similar results.
On first thought, it makes sense. When younger, since you don't have time to develop collateral blood vessels, you're more likely to die if you suffer a heart attack. The incidence of sleep apnea may increase as you get older, but the rate of death could go down as one gets older.
I wonder if chronic hypoxia in the brain causes similar protective effects. Since we know that hypoxia causes plaques that are similar to what we see in Alzheimer's, the answer is probably no. If you live long enough to beat obstructive sleep apnea, then is it more more likely you'll develop dementia?
What do you think about this study?