Depression: Factors Influencing Treatment Response

Factors Influencing Treatment Response

There are a number of factors which influence ultimate treatment response in MDD including patient characteristics, diagnostic issues, comorbidity, treatment-related complications including side effects and demographic factors. Reevaluation of diagnosis, comorbidity and the physician–patient relationship itself is often critical.

Suicide Risk

Patients with MDD are often at increased risk for suicide. Sui-cidal risk assessment is especially indicated as patients begin to recover from depression with increased energy and simultane-ous continued despair. Persistent suicidal ideation coupled with increased energy can often lead to impulsive suicidal acts. The careful attention to the physician–patient relationship can medi-ate suicidal urges through availability and accessibility. Outpa-tients and inpatients with MDD and melancholic features will often require antidepressant therapy addressing multiple neuro-transmitter systems, or ECT as well.

Psychotic Features

MDD with psychotic features requires careful assessment to rule out comorbid psychiatric conditions. The combined treat-ment with antipsychotic as well as antidepressant medication is indicated. In addition, electroconvulsive therapy is an effective intervention in psychotic depression and may be considered as a first line alternative.

Catatonic Features

MDD with catatonic features can be associated with significant morbidity due to the individual’s refusal to eat or drink. Active treatment with a benzodiazepine such as lorazepam 1 to 3 mg daily may offer short-term treatment response. Subsequent treat-ment with lithium alone or in association with antidepressants may be indicated given the possible link between catatonic fea-tures and bipolar vulnerability. If psychosis is associated with catatonia, then atypical antipsychotic medication or a course of electroconvulsive therapy may be indicated as well.

Atypical Features

Atypical features are associated with significant comorbid anxi-ety disorders, reverse neurovegetative symptoms such as hyper-somnia, increased appetite and weight gain, as well as fatigue and leaden paralysis. SSRIs are likely to be effective in individu-als with MDD with atypical features as well as MAOIs. Con-versely, tricyclic antidepressants, in particular, are unlikely to be effective in such individuals.

Severity

Individuals with mild to moderate depression may be effectively treated with psychotherapy, pharmacotherapy, or the combination. Individuals with severe MDD often require somatic intervention with antidepressant medication or electroconvulsive therapy.

Recurrence

Because MDD is a recurrent disorder, current treatment guide-lines (Hirschfeld, 1994) suggest maintenance antidepressant treatment at full therapeutic doses if there is a history of more than two prior episodes of MDD.

History of Hypomania or Mania

Any of the antidepressant treatments including medication, elec-troconvulsive therapy, light therapy, or newer somatic interven-tions may induce hypomania or mania in individuals who are vulnerable to bipolar disorder. Individuals who may have a fam-ily history of bipolar disorder should be carefully evaluated for treatment with lithium carbonate or other anticonvulsant mood stabilizers before antidepressant treatment because they are at particular risk for antidepressant-induced mania. Attention to this history of prior hypomania or mania as well as family history may promote treatment response if such individuals have mood stabilizing treatment offered initially.