Getting better, getting well: understanding and managing partial and non-response to pharmacological treatment of non-psychotic major depression in old age.

In general, the pharmacological treatment of non-psychotic major depressive disorder in old age is only partially successful, with only approximately 50% of older depressed adults improving with initial antidepressant monotherapy. Many factors may predict a more difficult-to-treat depression, including coexisting anxiety, low self-esteem, poor sleep and a high coexisting medical burden. Being aware of these and other predictors of a difficult-to-treat depression gives the clinician more reasonable expectations about a patient's likely treatment course. If an initial antidepressant trial fails, the clinician has two pharmacological options: switch or augment/combine antidepressant therapies. About 50% of patients who do not improve after initial antidepressant therapy will respond to either strategy. Switching has several advantages including fewer adverse effects, improved treatment adherence and reduced expense. However, as a general guideline, if patients are partial responders at 6 weeks, they will likely be full responders by 12 weeks. Thus, changing medication is not indicated in this context. However, if patients are partial responders at 12 weeks, switching to a new agent is advised. If the clinician treats vigorously and if the patient and clinician persevere, up to 90% of older depressed patients will respond to pharmacological treatment. Furthermore, electroconvulsive therapy is a safe and effective non-pharmacological strategy for non-psychotic major depression that fails to respond to pharmacotherapy. Getting well and staying well is the goal; thus, clinicians should treat to remission, not merely to response. Subsequently, maintenance treatment with the same regimen that has been successful in relieving the depression strongly improves the patient's chances of remaining depression free.