Diagnosis of dAD
One major challenge for clinicians is the limited capacity of AD patients to accurately convey their mood state. Both impaired language and executive functioning may contribute to a patient’s inability to fully integrate and convey the subjective experience of depression despite profound sadness. In that regard, much of the diagnosis relies on the caregivers' observations, since they have frequent contact with the patient.
Experience teaches that it is best to interview informants separately to allow for the greatest opportunity to be candid. A careful history must accurately assess the time course and pattern of any symptoms, and the use of rating scales can aid the clinician in assessing symptom severity. The Cornell Scale for Depression in Dementia (CSDD) is particularly useful because it integrates the patient and caregiver interviews to reach a composite rating.14Careful at tention in this often medically complex population to comorbid physical factors that may mimic or complicate the diagnosis of dAD is of equal importance (Table 1). Delirium should be considered when the changes are acute. Issues such as medication toxicity (especially from anticholinergic agents), infections, metabolic abnormalities, pain, con stipation, and other primary medical problems are common.
Medical conditions and medications mimicking dAD
Congestive heart failure
Chronic obstructive pulmonary disease
Lithium(Drug information on lithium) toxicity
Digoxin(Drug information on digoxin) toxicity
Phenytoin(Drug information on phenytoin) toxicity
Carbamazepine(Drug information on carbamazepine)
Chlorpromazine(Drug information on chlorpromazine)
Thioridazine(Drug information on thioridazine)
|dAD, depression of Alzheimer disease.|
Treatment of dAD
Once an accurate diagnosis is made, treatment requires a pragmatic ap proach. In all cases, specific nonbiologic interventions should be made first. Nonpharmacologic treatment approaches offer an advantage over medication therapies because of their safety and are often a first-line treatment in more mildly depressed patients or in cases in which the caregiver is depressed.15 In more severe cases, or in situations in which patients fail to respond to these efforts, biologic treatments take precedence. Unfortunately, many good treatment plans fail or yield only partial benefit. These cases require a persistent effort that continually con siders alternative approaches.
Several fundamental principles guide effective caregiver interventions; these are briefly outlined in Table 2. An es sential first step in interventions is to focus on education about dementia and depression. In many circumstances, this includes helping caregivers make needed changes in the patient's environment (providing adequate structure, increasing physical comfort, and reducing overstimulation) or their own ap proach (having reasonable expectations, remaining calm and reassuring, not rushing the patient). The importance of developing a predictable daily rou tine that incorporates pleasur able activities for the patient should be paramount. In addition, caregivers vary in their aptitude to problem-solve when difficult situations arise. Working with them systematically as problems pre sent can help them cultivate this skill. It is essential to convey a sense of hope, allow an opportunity to "vent,&334; and praise their successes. It is also important to help caregivers recognize when the level of care a patient requires ex ceeds their abilities and may necessitate a change in living arrangements. Another key support is the clinician's 24-hour availability in case of crisis.
Additional resources, such as a local Alzheimer Association support group (go to www.alz.org for listings) and reading material, including The 36-Hour Day16 can provide added support.
There are few studies of behavioral interventions in AD. One controlled study examined 2 interventions—one targeted to the patient, which focused on the provision of pleasant activities, and one that was caregiver-oriented and taught problem-solving skills.17 Both were more effective than usual care or a “wait list” control group in reducing depression in AD patients. In another controlled trial, an exercise training program combined with caregiver training also demonstrated an improvement in depression ratings.18 Often, interventions such as these are best implemented in the context of adult day treatment or in a senior citizens’ center. Helping caregivers acquire information about local programs through a local chapter of the Alzheimer Association or the local department of aging can go a long way in establishing the most appropriate setting for clinical benefit.