Get yourself a good UPS.
If power disturbances come frequently, then YES!, your PSU and/or your system will have shorter life.
Common power disturbances at home :
- permanent over or under voltage
- unstable voltage (up and down)
- bad grounding
- power spikes, either sudden drop or sudden high jump in a very short time.
Any of those are bad!
If you have any of those frequently, you must get a good UPS!