How does dimmesdales health declined

Dimmesdale's health has steadily declines sine Pearl's birth and the beginning of his silence. Today, we'd probably call it depression, but over time these things take a huge toll on the body, and Dimmesdale repeatedly punished himself emotionall and physically for a long time.

In Chapter 3, we have this direct quote;

"there was an air about this young minister, - an apprehensive, a startled, a half-frightened look, - as of a being who felt himself quite astray and at a loss in the pathway of human existence, and could only be at ease in some seclusion of his own."

In Chapter 12, we almost see him confess, but it never truly happens...

"all the dread of public exposure, that had so long been the anguish of his life, had returned upon him; and he was already trembling."

Further on, he still wants to confess but is it a true confession........ I don't know.......

"-behold me here, the one sinner of the world! At last! At last! I stand upon the spot where, seven years since, I should have stood; here with this woman."

I believe that Dimmesdale's death is the direct result of years of guilt, and that his health deteriorated because of the actions he took to hide his guilty secret.