Depression in the Medically Ill

Peter G Stenn, MD, Department of Psychiatry, University of Toronto, St Michael's Hospital and The Wellesley Hospital, Toronto, Ontario
The paper by Silverstone and others in this issue of the Journal (1) raises a number of interesting issues, especially for the consultation-liaison psychiatrist. Silverstone and his colleagues focus primarily on methodological difficulties of measuring depression in the medically ill. They make a number of recommendations to help correct measurement deficits. This editorial considers these measurement difficulties, addresses the more general problem of depression in the medically ill and, finally, delineates a direction for future work in this area.
Measuring Depression in the Medically Ill
As Silverstone (1) and other investigators (2) point out, the DSM-III, IIIR, and IV defining criteria of depression have included symptoms that can be produced or obscured by physical illness and are not necessarily related to depression. For this reason, and possibly others, an estimate of the prevalence of depression in medical illness has been elusive. There has been a great range in estimates: for example, Lansky (3) found major depression in 5.3% of his sample of cancer patients, while Bukberg (4) found major depression in 42% of his sample of cancer patients. Studies of multiple sclerosis patients found the prevalence of major depression to be 6% to 57% (5). A study of Cushing's patients (6) found major depression in 83% of patients.
On face validity, one might expect differences in depression between illness groups related to the degree of disability (or "perceived loss") or impact by the disease on quality of life. However, in order to study this question in a meaningful way, there must first be agreement on valid measures of depression in the medically ill. Silverstone (1) and other investigators (7) suggest methods for valid measurement. These methods should be used uniformly in future research in this area.
The Problem of Depression in the Medically Ill
Studies repeatedly demonstrate an underestimation of depression in the medically ill by medical and other health care staff (1). This finding takes on major significance when one considers the following two points:

depression in the medically ill exacerbates both morbidity and mortality (2);

depression in the medically ill greatly increases the financial burden borne by the patient and by society (8). Depression is likely to increase the risk of a self-perpetuating downward spiral involving decreasing self-care and poor progress in coping with the illness. Passive and active suicide attempts complicate this downward spiral.

Recent work in the area of psychoneuroendocrinology (9) and psychological factors affecting medical condition (10) documents the close link between mood states and illness. VanderKolk has stated, "It is thus no longer scientifically justifiable to make clear distinction between psychologic and biologic processes; rather we need to define our under- standing of the degree to which genetic, developmental, toxic and social factors converge to result in certain syndrome" (11).
Psychiatric Interventions: Effective Treatments of Depression for the Medically Ill
What gives these considerations even more import is that psychiatry has developed effective and practical treatments. Group psychotherapy, individual psychotherapy (12), and pharmacotherapy (13) work, with reasonable cost, and have a beneficial impact on quality of life in medical illness. New developments in pharmacotherapy have been especially helpful in treating depression in physically compromised patients (e.g., cardiac dysfunction or renal dysfunction).
In summary, case finding of depression in the medically ill is an area that needs more attention especially by the consultation-liaison psychiatrist, but also by others on the health care team. Depression in the medically ill is an important source of added morbidity and mortality, and most importantly, it can be treated.

References

1. Silverstone PH, Lemay T, Elliott J, Hsu V, Starko R. The prevalence of major depressive disorder and low self-esteem in medical inpatients. Can J Psychiatry 1996: 41:67-74.
2. Cassem EH. Depressive Disorders in the medically ill; an overview. Psychosomatics 1995; 36:S2-S10.
3. Lansky SB, List MA, Herrmann CA, and others. Absence of major depressive disorder in female cancer patients. J Clin Oncol 1985; 3:1553-1560.
4. Bukberg J, Penman D, Holland JC. Depression in hospitalized cancer patients. Psychosom Med 1984;46:199-212.
5. Minden SL, Schiffer RB. Affective disorders in multiple sclerosis; review and recommendations for clinical research. Arch Neurol 1990; 47:998-104.
6. Haskett RF. Diagnostic categorization of psychiatric disturbance in Cushing's syndrome. Am J Psychiatry 1985; 142:911-916.
7. Endicott J. Measurement of depression in patients with cancer. Cancer 1984; 53; S2243-S2248.
8. VanKorff M, Ormel J, Katon W, and others. Disability and depression among high utilizers of health care. Arch Gen Psychiatry 1992;49:91-100.
9. Stein M, Miller AH, Trestman RL. Depression, the immune system, and health and illness. Arch Gen Psychiatry 1991; 48;171-177.
10. Stoudemire A. Psychological factors affecting physical condition and DSM-IV. Psychosomatics 1993;34:8.
11. VanderKolk BA. The behavioural and psychobiologic effects of developmental trauma. In: Stoudemire A, editor. Human Behaviour: An Introduction for Medical Students. Philadelphia: Lippencot; 1990. p 226.
12. Spiegel D, Bloom JA, Kraemer HC and Goettheil E. Effect of psychosocial treatment on survival of patients with metastatic breast cancer. Lancet 1989;2:888-891.
13. Stoudemire A. Expanding psychopharmacologic treatment options for the depressed medical patient. Psychosomatics 1995; 36:S19-S26.