A year ago, I was burned out from a VPE level job for two years before and after moving down to a Engineering Lead (developer) job, responsibility greatly reduced, so were the stress level. I am able to take care more on myself and my family. So for the pay-cut and title downgrade, it's a good tradeoff so far.
Having said that, by no means responsibility is the only factor, I also feel that the work culture is also geographical. For instances, from my anecdotal experiences, same type of company in U.S. and Japan are working longer hours than the ones in Canada or France. A startup job in S.F. may seem a bit more stressful than a similar job in the Midwest/South. Your milage may vary.
PS: 8-hours of sleep is a great way to help me wean off the heavy coffee-drinking lifestyle. I remember reading an article recommended by my Jawbone UP wristband app about the quality of sleeping - REM sleeping is the key for brain consolidate memories. [1] [2]. As as aside, I love Jawbone's health awareness content. Too bad, they are going under :(
[1] http://www.huffingtonpost.com/dr-michael-j-breus/whats-in-a-...