Recognizing and Treating Geriatric Mood Disorders
Recognizing and Treating Geriatric Mood Disorders
Although aging may be accompanied by stresses, losses, and illnesses we should not accept debilitating mood symptoms as a routine concomitant of aging. Mood disorders and clinically significant mood symptoms disrupt older adults’ later years.
Many depressive states go unrecognized as such in older patients. Late-life mood symptoms can be subtle, atypical, or less numerous than required for a DSM diagnosis of major depressive disorder (MDD). An older adult may display less overt sadness, cloaking depression in a disguise of irritability or withdrawal. Some older adults manifest depression as a preoccupation with bodily dysfunction or disintegration.1 Concerns about loss of cognitive function may lead a well-intentioned clinician to focus on ruling out dementia rather than addressing depression.
Delusions, which are much more frequent among older patients with depression, can interfere with a clinician’s recognition of a primary mood disorder. Among the especially confusing diagnostic puzzles faced by clinicians, the distinctions between depression and personality disorder or substance use disorders requires careful and methodical evaluation of the history, symptoms, and mental status findings. The interaction of mood disorders with medical illnesses, too, can befuddle a clinician who attributes the mood symptoms to physical illness or a psychological reaction to physical disease. Often, there is a reciprocal relationship between medical and mood conditions that is most effectively addressed through simultaneous treatment of both conditions. One particular medical condition, vascular disease, can be associated with a depressive syndrome, vascular depression, which conjoins mood symptoms with executive dysfunction.2
Bipolar disorders, which typically begin in young adults, can present in older adults either de novo or as a recurrence of a disorder present earlier in life. Mania in late life is often characterized by increased irritability and dysphoria rather than euphoria and excitement. Secondary mania, the designation for symptoms caused by a medical illness such as cerebrovascular accident or infection, is far more common among older than younger patients. Treatment of bipolar disorder among older adults is similar to treatment of younger adults, although it requires attentive dosing, awareness of potential drug interactions, and alertness to adverse effects.
It is important to avoid overreliance on the DSM criteria for depression, since these criteria can lack adequate specificity and sensitivity in older patients. The diagnostic assessment of late-life mood disorders requires alertness to the medical burden associated with aging and the accumulation of chronic medical diseases.3 Physical examination and laboratory testing, often performed by a collaborating primary care clinician, are necessary for adequate assessment.
Suicide, often with firearms, is of particular concern when treating older, depressed patients. White men who are 85 and older commit suicide at a rate 5 times that of the general population. In many cases, the presence of depression might have been detected during a primary care visit and before a completed suicide.
The complex and mutually reinforcing relationship between depression and cognitive impairment is of great concern when treating older adults. Depression and dementia exacerbate each other symptomatically, and perhaps each promotes worsening of the other through inflammatory or other mechanisms.
In the past, the cognitive symptoms of depression were termed “pseudodementia,” in the belief that treatment of depression would cure the associated cognitive dysfunction. Longitudinal follow-up, however, has revealed that the “dementia syndrome of depression” may be a prodrome or even a risk factor for a later primary dementia.
Patients with Alzheimer disease or other dementias may express depression behaviorally, as aggression or vocalization or as resistance to care. Treatment with antidepressants is recommended when the symptoms resemble MDD, but studies questioning the superiority of antidepressants over placebo in these patients suggest that clinicians should be prepared to curtail an ineffective antidepressant trial.
For older patients with mild to moderate depression and sufficient cognitive capacity to benefit from an interactive approach, treatment of late-life depression frequently begins with psychotherapy or a combination of psychotherapy with an antidepressant. Evidence-based psychotherapies for older adults include cognitive-behavioral therapy, problem solving therapy, and interpersonal therapy.
All of the antidepressants approved by the FDA for treatment of depression have been used successfully in older patients, but clinicians often pass by the TCAs and MAOIs because the newer agents’ adverse effects are more benign.4 An SSRI such as sertraline is often chosen as the initial agent.5 Citalopram or escitalopram are also well-tested in the elderly, but controversial reports of enhanced risk for arrhythmia with these agents, when used at higher dosages, has resulted in more cautious use.
Serotonergic antidepressants are not without adverse effects in the elderly, and clinicians must remain alert to hyponatremia and bleeding, among other potential complications. Bupropion, in appropriate patients, treats apathy and depression with minimal weight gain, sedation, or sexual dysfunction. Patients at risk for seizure are not given bupropion, and those with psychosis or severe anxiety often do better with a different medication.
Mirtazapine is useful among depressed patients who can benefit from its anxiolytic, appetite-enhancing, and sedating effects. Neutropenia is a possible but infrequent complication, but sedation or appetite increase can interfere with compliance. A large number of patients fail to achieve remission with monotherapy, but many initial nonresponders benefit from use of the same augmentors helpful with younger patients.