Researchers Tackle the Underdiagnosis and Undertreatment of Late-Life Depression

June 1, 2004

Three studies over the past three years show that individuals over age 65 who are suffering from depression may still not be receiving the treatment they need. Is integrating treatment into primary care the answer?

The underdiagnosis and undertreatment of depression in older adults has been well documented in recent years, and while certain gains have been made over the last decade, researchers say there is much room for improvement. A study appearing in the Journal of the American Geriatrics Society (2003;51[12]:1718-1728) found that while rates of diagnosis for depression for patients aged 65 and older increased dramatically during the 1990s, "significant disparities by age, ethnicity, and supplemental insurance coverage persist in treatment of those diagnosed."

The researchers, led by Stephen Crystal, Ph.D., examined Medicare claims and interview data from 1992 through 1998 for nearly 21,000 recipients aged 65 and older who lived in community settings. They found that depression diagnoses more than doubled by 1998, to 5.8%. However, certain groups were significantly less likely to receive treatment: people aged 75 and older, people of "Hispanic or other" ethnicity, and people without supplemental insurance coverage. Hispanic beneficiaries who were diagnosed with depression received no treatment 43% of the time, compared with 31.9% of elderly white Medicare beneficiaries. People without supplemental insurance received no treatment 50.8% of the time, compared with 31.5% of beneficiaries with extra coverage. And 40.9% of diagnosed beneficiaries who were 80 and older received no treatment, compared with 24.4% of beneficiaries aged 65 to 69.

Even in the best of conditions, mental health treatment for late-life depression remains largely inadequate, as indicated by the disproportionate rate of suicide among the elderly. While adults 65 and older make up about 13% of the U.S. population, they account for 18% of suicides. According to the U.S. Surgeon General's Office, more than 70% of suicides in older patients occur within a month of a primary care visit, and more than 20% occur on the same day.

Mental health services for older people need to be integrated with primary care, Gary J. Kennedy, M.D., past-president of the American Association for Geriatric Psychiatry (AAGP), told Psychiatric Times. The interaction of mental and physical illnesses in older adults is so intimate that it is counterproductive to have separate systems. A number of studies funded by the National Institute of Mental Health and private organizations such as the John A. Hartford Foundation, the Robert Wood Johnson Foundation, and the John D. and Catherine T. MacArthur Foundation clearly indicate that there needs to be someone to manage the depression at the site where the patient receives primary care services, Kennedy said. Typically, that means co-locating a psychiatric social worker, master's level psychologist or psychiatric nurse with off-site support from a psychiatrist. But that arrangement is rare. "More often than not, the primary care physician is left to his or her own guesswork as to how to recognize the depression and how best to treat it," said Kennedy, who is also director of the division of geriatric psychiatry at Montefiore Medical Center in New York City.

Most primary care doctors have not been trained in how to use the most recently introduced antidepressants in older patients, "and they've certainly not been trained in even basic psychotherapy," he said. "So we're really asking the primary care physician to provide this mental health service when they're ill-prepared to do so."

The other complicating factor, Kennedy added, is that antidepressants aren't as easy to effectively prescribe as people like to think. In the best of studies, the first antidepressant prescribed helps only about 40% of patients. By contrast, the first selected antihypertensive medication lowers blood pressure adequately about 60% of the time. And that is where some of the treatment disparities arise. Patients who receive care in public clinics do not have integrated services and are not getting the kind of aggressive treatment that is warranted for major depression.

"I'm not faulting the primary care physicians," Kennedy said, "because to expect them to treat an illness for which they've not really been well trained, just like expecting me to treat hypertension, puts the patient and the physician at a disadvantage."

Older adults also feel more stigmatized about having a psychiatric diagnosis. "They're from a generation where psychiatric diagnosis implied schizophrenia or a state hospital," Kennedy explained. Younger patients, on the other hand, are more inclined to accept depression as a prevalent disorder that can be helped with medications and talk therapy.

When people do not get care, it's partly a function of the patient not telling the physician everything, Martha L. Bruce, Ph.D., M.P.H., of the department of psychiatry at the Weill Medical College of Cornell University, told PT. At the same time, clinicians can misinterpret what a patient says, especially if there are differences in ethnicity, culture or language. System issues such as what a system pays for and where services are located also create obstacles to care. These issues can create a significant deterrent, especially for low-income patients.

The PROSPECT Study

Bruce was the lead author on a study examining the impact of primary care-based interventions on reducing depression and major risk factors for suicide in older patients (JAMA 2004;291[9]:1081-1091). The intervention consisted of a trained care manager who worked on-site at the primary care office to offer guideline-driven antidepressant treatment and encourage patients to adhere to treatment recommendations.

The motivation for doing the Prevention of Suicide in Primary Care Elderly: Collaborative Trial (PROSPECT) study was to reduce the risk of suicide resulting from late-life depression. The study found that more than two-thirds of patients who had expressed suicidal ideation and received intervention treatment from a care manager were no longer suicidal after four months, and 70.7% no longer had suicidal thoughts after eight months. By contrast, only 43.9% of patients receiving standard care no longer had suicidal thoughts after eight months.

"I think we have very clear evidence that you can effectively treat depression in older primary care patients and that primary care physicians can do that easily and well with the assistance of a care manager," Bruce said.

The study used nurses, social workers and master's level psychologists to serve as care managers, providing components of chronic care such as symptom assessment and the monitoring of side effects and medication adherence. The study's screening process identified patients with depression who were not likely to have discussed their symptoms with a physician, Bruce said. Researchers also did a full assessment on a sample of patients who did not screen positive for depression in order to identify patients who denied existing symptoms in a straightforward screen. Over a year's time, the same percentage of patients in each group got better, but patients in the intervention group got better faster. Relief of symptoms of depression peaked at four months for the intervention group, meaning they suffered for eight fewer months than did patients receiving standard care. Not everyone improved, however. About half of all patients remitted to major depression over the course of a year, Bruce said, indicating that continuing efficacy research on treating late-life depression is needed.

But the care manager intervention did succeed in getting more older patients into treatment. Four months into the study, about 90% of patients in the intervention group were being treated either with medication or psychotherapy or both. But in the usual care group, only about 52% of patients were being treated. "Part of how this works is that people get treatment and then they get their treatment monitored," Bruce said.

Comorbidity

The onset of major depression in late life is most often a comorbid condition that follows a suddenly disabling condition such as stroke, heart attack, late-onset vision loss or hip fracture, according to Kennedy. But even minor depression can have a disabling component when it is accompanied by suicidal thought. A small but interesting finding from the PROSPECT study, Kennedy said, is that minor depression with suicidal ideation was more effectively treated by primary care providers who used depression care managers than by primary care providers alone. However, primary care providers alone did as well as physicians who had depression case managers in treating patients with minor depression but no suicidal ideation. Patients screened for depression are usually asked whether they have been depressed or lost interest in things over the last two weeks. But new research from Kennedy suggests that these screening questions fail to pick up most patients who have suicidal ideation and answer positively if in the previous two weeks they had thought that life was not worth living or of harming themselves.

Kennedy examined data from the Bronx Aging Study on 471 community-residing adults aged 70 and over who were free from cognitive impairment. He found that only half of individuals with suicidal ideation (eight out of 15) achieved a score indicating they were "possibly depressed" on a nine-item depression assessment. He presented the findings, which have yet to be published, at AAGP's annual conference in February.

"If you want to screen for depression, you probably need to ask people about suicidal thought, as well as about mood disturbance and loss of interest," he said. Most suicidal thought would have been lost in the usual depression screening that occurs when a patient has a condition such as congestive heart failure.

Need for Better Home Care

Older, sicker people generally get undertreated to begin with, and home care appears to be an especially undertreated area, Bruce said. In a study published in the American Journal of Psychiatry (2002;159[8]:1367-1374), Bruce and colleagues found that the prevalence of major depression among seniors in home care (13.5%) was more than twice that of seniors in primary care (6.5%). About 85% of home care by visiting nurses is administered to older people with acute medical or surgical conditions such as wound care, medication management and nursing care. Medicare pays for an initial three months of care. If longer-term home care is needed, Medicaid must pay for it.

In this study, only 22% of home care seniors with major depression were receiving antidepressants, and none were receiving psychotherapy. Of patients receiving medication, about one-third had been prescribed subtherapeutic doses. Only 12% of home care patients with depression were receiving adequate treatment as defined by type of medication, dosage and adherence, Bruce said.

Since then, Bruce has done further research on whether these cases of depression are a reaction to a medical crisis that goes away once the patient's condition improves. "In the majority of cases it persists, and it is related to poor medical and functional outcomes," Bruce said.

Much of Bruce's research now focuses on strategies for improving home health care. The task is complicated by the clinical differences among providers and by challenges in getting reimbursed for more integrated services. In a NIMH-funded study, which began two years ago in partnership with three home care agencies, she is attempting to develop training programs for clinical home care staff in assessing and managing late-life depression and improving care for patients with depression. While research in primary care and home health care is designed to improve access to care through non-mental health care specialists, Bruce said, this makes the role of psychiatrists even more important because they are needed to supervise front-line staff and to care for the most complicated cases.

"It's not as if it's competition," she said. "It's actually a nice triage system, if it works."