Depression

Key Facts

  • Depression is common in PD.
  • Motor symptoms, sleep disturbance, weight loss and cognitive dysfunction may mimic depressive symptoms.
  • Several pharmacological agents are appropriate for the treatment of depression in PD.
  • Patients under management for depression secondary to PD should be monitored monthly after initiating therapy, and then frequently until stable.

Clinical Best Practices

  • All PD patients should be evaluated at least once a year for depression.
  • Patients with a history of depression should be evaluated more frequently.

It is estimated that up to 50% of patients with PD may experience some form of depression during the course of their illness. The majority of these individuals experience minor depression. However, major depression can occur roughly in 5% to 10% of cases. Onset of depression or depressive symptoms may pre-date the diagnosis of PD. Early-stage patients may struggle with diagnosis, and this may contribute to symptoms of depression.

Common Causes

  • Changes in dopamine, serotonin, and norepinephrine in the brain
  • Psychological reaction of a patient to the diagnosis of PD
  • Isolation induced by symptoms of the disease

Diagnosis

  • Medical history and clinical examination
  • Endorsed feelings of guilt and hopelessness more common in PD depression

Barriers to Diagnosis

  • Parkinson’s “masked face” may be mistaken as just a motor feature, but this could be a depression feature.
  • Motor symptoms, sleep disturbance, weight loss, and cognitive dysfunction may mimic depressive symptoms.
  • Parkinson’s patients may experience limited self-awareness of their own or others’ emotions.
  • There exists a stigma of the diagnosis and treatment of depression.

Treatment Options

Several pharmacological agents are appropriate for treatment of depression in PD patients including:

  • Selective serotonin reuptake inhibitors (ie, sertaline, fluoxetine)
  • Selective norepinephirine reuptake inhibitors (ie, venlafaxine)
  • Tricyclic antidepressants (ie, nortriptyline, trazodone)

Important Caveats to Therapy

  • To reduce confusion in interpretation of masked face and slowness, optimize motor symptoms management first.
  • You may also administer the Beck Depression Inventory that is validated in PD.
References: 

Aarsland D, Marsh L, Schrag A. Neuropsychiatric symptoms in Parkinson’s disease. Mov Disord. 2009;24(15):2175-2186.