I started suffering some dementia. Was put on Alzheimer Medicane that helped little. Note: late 30s.

Turned out it was a clotting problem. Genetic Factor 5 Leiden. I was having minor strokes a couple times a week. Each time would take about a month to recover mentally. But having them faster then that. Completely cleared up as soon as I went on blood thinners.

Later I learned whole extended family had been through this.

Dementia can have many causes, sometimes it’s something we know about, but hard to diagnosis.