The old ticker
As we age, our heart muscle wears out — thus causing heart problems. There is a link between insomnia and chronic heart failure. Chest pain can make it difficult to relax, fall asleep, and stay asleep. And to make it worse, lying down can cause shortness of breath — which then exacerbates the problem. As a result, chronic heart failure can lead to fatigue and interrupted sleep.
Changes in circadian rhythm
As we age, our ability to achieve deep sleep is limited. This is one reason why older people spend less time in bed. The circadian function decays with aging. Think of it as a dynamic clock — an ever-changing rhythm in our behavior, physiology, and metabolism. Patterns in this rhythm change as we age making it harder to sleep.
