Why older adults have fragmented sleep patterns?

A new research has explained older adults have trouble sleeping because of a group of neurons are found to function as a 'sleep switch' in the brain.

Researchers at Beth Israel Deaconess Medical Center (BIDMC) and the University of Toronto/Sunnybrook Health Sciences Center showed that these inhibitory neurons are considerably diminished among the elderly and individuals with Alzheimer's disease, and that this, in turn, is accompanied by sleep disruption.

Clifford B. Saper, MD, PhD, Chairman of Neurology at BIDMC, said that sleep loss and sleep fragmentation was associated with a number of health issues, including cognitive dysfunction, increased blood pressure and vascular disease, and a tendency to develop type 2 diabetes and it now appeared that loss of these neurons may be contributing to these various disorders as people age.

Saper said that they found that in the older patients who did not have Alzheimer's disease, the number of ventrolateral preoptic neurons correlated inversely with the amount of sleep fragmentation and the fewer the neurons, the more fragmented the sleep became.

The study is published in the journal Brain.