Annals of Long Term Care

Author Affiliations: Dr. Attupurath is in private practice in New Haven, CT; Drs. Menon and Nair practice medicine in Kerala, India; and Drs. Muralee and Tampi are at Yale University School of Medicine, New Haven, CT.

Introduction

Major depressive disorder (MDD) is undiagnosed in approximately half of all elderly persons with this disorder.1 Contributing to this fact is that elderly patients are more likely than their younger counterparts to see their primary care physician rather than a psychiatrist.2 Major depressive disorder is not uncommon, occurring in approximately 2% of all community-dwelling elderly.3,4 In primary care clinics, the prevalence increases to approximately 6-9%,5 while among the patients admitted to acute care hospitals, the prevalence is approximately 10-12%. Among all nursing home residents, 12-14% meet the criteria for MDD.6 However, the rates of depressive symptoms in general are much higher, with studies showing prevalence rates between 30% and 45%.3,7

Beyond its prevalence, geriatric depression has severe ramifications, carrying with it an increased risk of both morbidity and mortality. Elderly patients with depression have a 1.5-3 times increased morbidity and a lifetime suicide risk of approximately 15%, with nearly 10% of these patients dying annually from suicide.3 Given this broad-reaching clinical significance, it is imperative for the primary care, long-term care, and psychiatric communities to appreciate the unique presentation, diagnosis, and treatment of MDD in geriatric patients as compared to the general population. In this article, we review late-life depression and highlight the issues that need to be considered in treating patients with this disorder.

Presentation and Diagnosis

The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM–IV-TR) defines MDD as a condition characterized by the presence of depressed mood or loss of interest or pleasure. Associated symptoms include changes in appetite or weight (5% of total body weight), sleep, energy, concentration, and psychomotor activity, as well as feelings of inappropriate guilt or worthlessness, and recurrent thoughts of death or suicide.

Although not part of any standardized classification system, late-life depression is generally described as depression arising in adults older than 65 years of age who have not had a previous history of mood disorder.6 Population studies reveal that the presentation profile of late-life depression is distinct from that of the younger population. In general, patients with late-life depression are less likely to have a family history of depression than their younger counterparts.8 The symptoms are more likely to develop insidiously, and these patients are less likely than their younger counterparts to attribute their symptoms to depression as opposed to “the normal aging process.”3

Elderly patients with depression usually present with higher rates of psychotic symptoms as compared to their younger counterparts. Proposed explanations for this disparity include age-related deterioration of cortical areas, neurochemical changes common in aging, comorbid physical illnesses, social isolation, sensory deficits, cognitive changes, and polypharmacy.9 The Epidemiologic Catchment Area survey reported a range of psychosis from 16% to 23% in an older adult population.10 In addition, psychotic late-onset depression accounts for nearly 25-50% of admissions to the inpatient geriatric psychiatry units.11 Patients may present with delusions that are nihilistic, somatic, or poverty-based,3 and these patients also appear to have higher rates of insomnia, somatic symptoms, diurnal variation of mood, and poor insight.11 Although delusions are common, hallucinations appear less likely in these patients.