Type C was initially identified in malignant melanoma patients, and was found to be related to a number of health outcomes: increased delay in seeking treatment for symptoms, faster disease progression, greater tumor depth, lesser lymphocyte (white blood cell) activity at the tumor site.

Anecdotally, I think that Type C coping can be involved in some pain syndromes. Type C copers tend not to realize that they're under stress, and so they stay in stressful situations. The body's need for relief can manifest as pain - for example, migraines, in one clinical case I saw. My client's migraines got much better once she started noticing symptoms of stress and the need to relax before she got to the crippling-pain-ER-visit stage.