General medical illness can contribute to affective disorders in elderly patients. Treating the medical illness is an integral part in treating depression in these patients.
Several factors associated with cancer contribute to an increase in both biological and psychological risk, including suicidal ideation and completed suicide.
Vitamin deficiency may increase the risk of depression; moreover, this deficiency has been linked to poor antidepressant responses. Nevertheless, vitamin deficiencies are often underappreciated, and there are no clear clinical guidelines regarding screening for vitamin deficiencies in MDD.