We all know the pleasure of getting a great night of sleep and how refreshing that feels in the morning. As I have aged, getting good sleep has become more difficult. I have tried relaxation techniques, meditation and some pharmaceutical sleep aids to return to that full night's sleep. Recently, a large study in Great Britain has examined how humans sleep. The researchers classified sleep patterns into five different clusters and 16 different types of sleep. It is so much more complex than most of us ever imagined - no wonder I am having trouble sleeping.

Scientists analyzed sleep data from 100,000 people in the United Kingdom measuring movements from wristband devices to monitor their sleep. They collected information about individual sleep patterns, times, duration of wakefulness and arm movements that occurred during the sleep period. Those of you with a Fitbit or similar device know what we mean. Each participant was followed for multiple nights to produce the large dataset examined in the study. What emerged was a comprehensive look at the diversity of the patterns of what we call "sleep." One word, sleep, is hardly sufficient to describe our nightly ritual.

The scientists put the huge dataset into a computer and analyzed it using statistical methods to find patterns in it. Patterns emerged in the lengths of time people sleep for and how much time they spend awake during the night. The data turned up five broad categories of sleep patterns.

Those in the Category 1 cluster have long duration sleep but have night awakening insomnia. Cluster 2 is split into a and b subtypes for those with irregular sleep schedules and those with fragmented sleep. Cluster 3a people experience insomnia with normal duration sleep, while 4a people have short duration sleep with insomnia. Cluster 3b are those who sleep deeply but have trouble getting back to sleep when they awake during the night. Other Cluster 4 groups include morning people, long sleepers and night owls. This group also contains those identified as pre-insomnia, which means they had multiple sleep/awake cycles with an overall struggle to stay asleep. The people in cluster 5 are those fortunate enough to have uninterrupted sleep and no daytime sleep.

We have made great progress in understanding sleep in recent years. Disruption of the "normal" sleep pattern has been linked to the development of dementia and deficits in cognitive function. Some studies even suggest that the loss of a single night's sleep can have lasting effects. The more we understand about human sleep, the better positioned we are to devise effective treatments in the future.

This study broadens our concept of sleep and insomnia and could lead to new treatments to help with this frustrating condition. Future research will focus on examining personal attributes like occupation, lifestyle, medical history and medications among other variables on sleep. The ultimate goal will be to reach an overall assessment of a person's sleep style and its impact on their health. It is more complicated than counting sheep.

Hopefully, these encouraging results in mice will translate into successful treatments of people with similar cancers.