Geriatric Depression

Geriatric depression (late-life depression) is one of the major geriatric giants.

Prevalence

The community prevalence rates of late-life depression is 11.2% for combined symptoms of major and minor depression.[1]

Generally, the diagnosis of late life depression can be made using DSM 5 criteria. Older adults are less likely to directly endorse being “depressed” or “guilty/hopeless,” but will endorse anhedonia.

Awareness of other medical causes must be thoroughly considered due to higher rates of medical comorbidities. For example, the criterion for “markedly diminished interest or pleasure” may overlap with or be confused with the apathy due to dementia or an underlying neurological disease. Psychomotor slowing, sleep changes, fatigue, low energy, weight loss and/or poor appetite can also be caused by an underlying medical illness, major neurocognitive disorder, substances (alcohol or opioids). Feelings of worthlessness and suicidal ideation can also be due to end-of-life issues.[2]

A complete assessment for late-life depression requires:

  • Reviewing the diagnostic criteria for late-life depression
  • Performing a physical examination and ordering laboratory investigations to identify any medical problems that could contribute to or mimic depressive symptoms (e.g., hypothyroidism, anemia)
  • Reviewing current medications, allergies, and substance use
  • Reviewing current stresses and life situation
  • Assessing level of functioning/disability
  • Considering support system, family situation, and personal strengths

Older adults have one of the highest suicide rates in North America, largely due to the risk in older white males (higher intent and likelihood to complete suicide).[3]

  • B12

Depression, dementia, and mental impairment are often associated with vitamin B12 (cobalamin) deficiency and folate deficiency, especially in the elderly. Although laboratory norms and ranges may show that a serum vitamin B12 level between 200 pg/mL and 900 pg/mL is considered normal, a minimum level of 300 to 350 pg/mL is desirable in the elderly.[4]

Cognitive behavioral therapy (CBT), problem-solving treatment (PST), and interpersonal therapy (IPT) has strong evidence in late-life depression.[5]

Monitor for Hyponatremia!

Monitor for electrolytes (in particular sodium) within one month of starting an SSRI. This is especially important in individuals taking other medications, such as diuretics, which can cause hyponatremia.

Buproprion, mirtazapine, moclobemide, and venlafaxine are all relatively safe in the elderly. They have lower anticholinergic effects compared to older generation antidepressants. This makes them well tolerated by patients with cardiovascular disease. However in clinical studies, tricyclic antidepressants and MAOis have been shown to be more efficacious in the treatment of geriatric depression.[6]

If tricyclic antidepressants (TCAs) need to be used, nortriptyline and desipramine have the lowest anticholinergic burden, and are the most tolerated of the TCAs.[7]

Lithium augmentation for treatment-refractory depression has some evidence.[8]

  • Older adults who receive ECT have a lower mortality rate compared to other depression treatments (i.e. - antidepressants)[9][10]
  • Right unilateral, ultrabrief pulse ECT (average of 7 treatments of ECT), when combined with venlafaxine, can be a rapidly acting and effective treatment in depressed geriatric patients. There very good safety and tolerability when this combination therapy is used.[11]