Sleep disorders and dementia

Abstract Sleep disorders and dementia have a bidirectional relationship, albeit not fully understood yet. Thus, diagnosing and treating sleep disorders might help to protect patients’ brains from cognitive decline evolving into dementia. In this chapter, we pinpoint the connection between sleep disorders and cognitive impairment advancing to Alzheimer’s disease, including sex- and gender-related aspects. We highlight sleep disorders and their implications for Alzheimer’s disease. Moreover, we focus on insomnia, obstructive sleep apnea syndrome (OSAS), and rapid eye movement (REM) sleep behavior disorder (RBD) as relevant and modifiable risk factors of dementia. Current evidence on sex- and gender-related differences in patients experiencing sleep disorders and suffering from mild cognitive impairment (MCI) or Alzheimer’s disease is sparse. Therefore, we provide current knowledge and future perspectives to enhance awareness of relevant differences between male and female patients experiencing sleep disorders to accelerate early diagnosis, treatment, and prevention of sleep-related cognitive impairment evolving into Alzheimer’s disease.