A gene linked to job-related exhaustion in shift workers may increase the risk of Alzheimer’s, according to a Finnish study published in the journal Sleep.

Researchers led by Tiina Paunio, M.D., Ph.D., found that a variation in the melatonin receptor 1A (MTNR1A) gene is linked to the risk of Alzheimer’s disease in the elderly. It also reduces tolerance to shift work among the working age population.

While it’s one of many factors, the news means a genetic predisposition combined with a lifestyle that disrupts the circadian rhythm can increase the dementia risk.