Serum Anticholinergic Activity: A Possible Peripheral Marker of the Anticholinergic Burden in the Central Nervous System in Alzheimer’s Disease

Figure 3

The plasma steroid level is high early in the morning and rapidly declines later. We hypothesized that this rapid decline might cause disinhibition of the immune system. Thus, the immune system may be activated in the afternoon, in the evening, and at night. If the levels of steroids in blood rise, then the decline of the steroid level also becomes larger, which causes a more active inflammatory state and increased anticholinergic activity (AA, red arrow). AA: anticholinergic activity.