Fluorescent tubes and halides tend to have shifts in color spectrum with age, also shifts in luminosity.
LEDs driven at 100%, tend to develop those traits after 7 or so years. If overdriven, much quicker of course. Overall, LEDs have a much sharper drop off in spectrum due to the way their designed. Not sure if you'll see much of a spectrum swing, but you will see an intensity/luminosity swing with age.
The DIY LED light I'm using now has about 4 years or so on it and it still works the same as it did when new. But, it is running at around 350 mAmps - low power. The LEDs are Ebay bargain LEDs from China.