Studies have found that both naturalistic and chronic stress are associated with delayed would healing. Examples include dentist students who took 40% longer to heal wounds placed on the roof of their mouths, on the hard palate before an examination compared to wounds placed at the end of their summer break .
In addition, study on healthy young men who perceived they were under stress took longer to heal wounds compared to those who did not report symptoms of psychological distress.
Similarly individuals with leg ulcers who exhibited high levels of anxiety and depression were more likely to heal slower than those reporting lower levels of anxiety .
Surprisingly, even common stress situations such as discussion about martial problems can delay wound healing . Aggression and hostile behaviour further delays healing process. This was discovered within martial relationship in which blisters took longer to heal in confrontational relationship compared to supportive interactions.
Studies addressing relationships between anger expression and wound healing found that anger control was a significant predictor of the healing progress. Those who have little or no control over anger are 4 times more likely to take longer to heal than those who have learned to control their anger.
The implications being that stress induction can delay wounds healing, giving rise to great chances of infection, greater stress on the immune system which would further decrease the healing times.
Ref: Keicolt-Glaser et al, Hostile martial interactions, proinflammatory cytokine production and wound healing. Arch. Gen.Psychiatry 2005