I have a family member that I'm worried about, that has taken Zolpidem for several years straight (apart from minor breaks in between prescription refills because of overconsumption during the previous refill...).
Zolpidem increases risk of depression, falls and bone fracture, poor driving, suppressed respiration, and has been associated with an increased risk of death [2].
I would recommend you to seek a second opinion from another medical professional about whether this family member should perhaps slowly taper off of the Zolpidem.
[1] https://www.nice.org.uk/guidance/ta77/chapter/1-Guidance
[2] https://escholarship.org/content/qt08d9f3d5/qt08d9f3d5.pdf?t...
However, Z-drugs(and benzos as a sleep aid) generally should not be used daily for longer than a few weeks until a better solution is found. Unfortunately, doctors often do this anyway, following the path of least resistance, I suppose.
I wouldn't worry about any kind of brain damage, but I would recommend reviewing their options, maybe seeing another doctor. Lots of people can manage just fine with something like extended release melatonin, or indeed nothing.
Zolpidem is best used for a couple to regularize sleep patterns and help establish proper sleep hygiene. Trazodone at lower doses is better for long term use, especially in older patients.