A JAMA article covered the concept of resident "burnout," defined as "a pathological syndrome in which emotional depletion and maladaptive detachment develop in response to prolonged occupational stress." Thomas NK.  Resident burnout. JAMA.  2004 Dec 15; 292 (23):2880-9.  Review. PMID: 15598920 [PubMed – indexed for MEDLINE]

Burnout is measured in three dimensions:  emotional exhaustion, depersonalization, and low sense of personal accomplishment.   

This syndrome appears to affect women and men equally. Potential sources of burnout include time demands, lack of control over time management and work planning, interpersonal relationship conflicts, inherent difficult job situations, inadequate feedback and problematic dependency on superiors. 

In a program that successfully reduced work hours to meet with ACGME requirements, levels of emotional exhaustion, depersonalization and feelings of personal accomplishment did not significantly change. These results indicate that burnout is not merely a result of long work hours and more research needs to be done to reduce resident burnout.