UKH

Has anybody out there had or heard of long term effects of altitude sickness (4 years)

It typically doesn't last too long (depends on how long you were exposed to high altitudes for?). If its been 4 years, I'd suggest its something else that manifests as similar symptoms which you might want to get checked out.

After a month at altitude in the Alps this summer I never seemed to recover. I went to see the doctor after two months and was diagnosed with Lymes disease which I must of picked up from a tick bite in the Cairngorms before I left. Get yourself checked out is my advice.