Sleep and Aging

It seems as though just as we outgrow the notorious teenage problem of being unable to fall asleep at a healthy hour, life and all of its relentless responsibilities catches up with us and piles on top of us, offering us absolutely no relief from the sleep deprivation that seems to have followed us from puberty on up. As our bodies age and our muscles, bones, skin and internal organs begin to deteriorate in middle age, our sleep cycles do as well. Though we can blame much of it on nature, the truth is that much of our middle-aged sleep deprivation arises from our own dreams and desires. We prioritize the business of our lives so that sleep is shattered by our schedules rather than by hormones or a shifting biological sleep clock.  The requirements of our work lives, the need to care for our families and all of the other million things that drive us all to run ourselves ragged also end up infringing upon our sleep time, in large part because we still have not correctly prioritized our bodies’ need for rest.  Most middle-aged adults get seven hours of sleep per night, a number that is probably less than they need. Unfortunately, sleep data is extremely low for this particular age group, in large part because they are unable or unwilling to sacrifice enough time to participate in the sleep studies that would provide the information. We do know that our need for sleep slowly declines with age, so the fact that seven hours is less sleep than we needed as teenagers is not as alarming as it could be, but in all likelihood it is still not the amount of sleep that is needed for us to be truly happy and well rested and able to function at the peak of our ability. Middle age is the time when many sleep disorders first start to make themselves known, though they are often masked as a result of trying to maintain both a social schedule and a work schedule along with caring for small children. Many of them are caused by physical changes. Weight gain, menopause, the need to urinate in the middle of the night, all play a role in increasing numbers of adults reporting insomnia. Beyond our middle-aged years, the sleep of the elderly is severely impacted by physical problems such as apnea in surprisingly large numbers. Just under fifty percent of participants in a study who were aged between 65 and 88 showed signs of sleep apnea or experienced high numbers of episodes of microarousals. These brief awakenings (lasting approximately three seconds) may be short but are extremely disruptive, and can have a profound impact on the level of daytime sleepiness. Even though they are so short-lived that the sleepers who experience them still get almost the same total amount of sleep time over the course of the night, it diminishes overall alertness.  These awakenings may occur up to 1,000 times in a night. Still, though the elder adults did report feeling sleepy during the day, their scores on a Multiple Sleep Latency Test (MSLT) were substantially better than they would have been had the same number of microarousals happened to a younger person. This is a clear indication that the older we get, the less sleep we need, or the less that sleep debt impacts us. There have been a number of sleep studies done that have pointed to this same result. Examination of lab results and of brain waves occurring in older adults have shown that the older we get, the less growth hormone we release during the beginning of our stage four sleep. The sleep stage itself diminishes, as does stage 3.  Those stages, previously integral to our body’s ability to make us taller and stronger, evolves into a time for us to restore damaged cells, but as we age less and less of this type of repair goes on. It is difficult to tell whether that is because our bodies have stop producing growth hormone, or whether we stop producing the hormone because as we age our bodies stop sending out orders to repair themselves entirely. Another change that occurs as we enter our senior years is similar to, yet diametrically opposed, to what happens to us during our teen years. Just as teenagers become more and more alert during the midnight hours and are unable to fall asleep until 1:00 a.m., older adults find themselves awakening much earlier in the morning, frequently before the sun rises. However, unlike during our teen years we are also more likely to go to sleep earlier, so our sleep debt does not build in the same way. Still, studies have shown that the amount of sleep that we need does diminish. This does not, however, minimize the impact of sleep disorders such as sleep apnea or restless leg syndrome. Sleep deprivation in the elderly can contribute to confusion, and sleep apnea puts a tremendous strain on the heart, lungs and the entire body that can have deadly results. One thing that many older people complain about is that their sleep is much lighter, and therefore they are prone to being easily awakened by noises or bright light. This may be a result of the fact that sleep debt seems to have a decreasing impact on us as we age, and therefore the sleep that we get is not as deep.  Many retired people complain about the fact that their ability to sleep has diminished just when they have the time to sleep for as long as they want to.  Many researchers have compared the decline in sleep patterns to the same type of regression that the rest of the body goes through, until finally when we are extremely elderly we end up sleeping 16 to 20 hours per day, in much the same way that we did when we were infants.