These areas include the advancement of techniques such as the accumulation of amyloid-β and tau proteins, the monitoring of cerebral hypometabolism rates etc. The primary objective of this study is to explore the intricate interplay between Alzheimer's disease (AD)—other dementias (D) and various chronic illnesses in terms of time, intensity, and connectivity. Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.