Sleep
Sleep disturbances are seen as a possible risk factor for inflammation in Alzheimer's disease. Sleep problems have been seen as a consequence of Alzheimer's disease but studies suggest that they may instead be a causal factor. Sleep disturbances are thought to be linked to persistent inflammation.[70]

Metal toxicity, smoking, neuroinflammation and air pollution
The cellular homeostasis of biometals such as ionic copper, iron, and zinc is disrupted in Alzheimer's disease, though it remains unclear whether this is produced by or causes the changes in proteins.[9][71] Smoking is a significant Alzheimer's disease risk factor.[1] Systemic markers of the innate immune system are risk factors for late-onset Alzheimer's disease.[72] Exposure to air pollution may be a contributing factor to the development of Alzheimer's disease.[9]