I entered the shadow of the watchtower at 35. As to being more adversely affected, I don't think so. The difference, IMHO, is that when one enters as an adult, they give up and walk away from their life and friends. I did! The result is, now that we have left that shadow, we're finding our true friends and family hadn't abandoned us. They were just waiting for us to return (come to our senses). On the other hand, those that I know who have grown up with only the watchtower as their guide in life, have to make choices about their life that they may not be equipped to make to the benefit of their growth. Youth, as I remember it, was the time to test the waters, to see which direction to go, to grow up and be allowed to make mistakes. Those who grew up as a witness now are leaving their cloistured lifestyle, the time for experimentation may have passed.
I'm finding it much easier walking away compared to the many on this board...but my (our) family was on the outside waiting...maybe that's the difference.
BadJerry