Extend life of 5mw red laser

Im using a red diode with integral current controller for a continuous data acquisition application. Its a generic product by AixiZ 650nm 5mW 3.2VDC 8x13mm. I will have dozens of these at remote locations and so need the lasers to last a few years at least. What is a good way to extend the laser life ? Reduce power via reduced voltage ? Run at very low voltage, then pulse up to rated volts for millisecond to take data reading, then go back to idle; that is, use pulsing and duty cycle ? Is square wave o.k. for this, or ramp up/down slowly ? Use heat sink cooling fins on copper housing ? Your insight on this problem is greatly appreciated.