Psychiatrists are quick to point out that primary care physicians do a poor job when treating depression. However, most psychiatrists are not that good at treating depression themselves.
I believe that truly treatment-resistant depression in elderly patients accounts for less than 10% of the patients we treat. (Arch. Gen. Psychiatry 2002;59:729-35) But if you look at treatment as usual, we help only 30%-40% of the patients we see. I make the claim – and I’m ready to say it publicly – that we should be able to do about twice as well as that. Not only do we not help as many people as we should, but we hurt quite a few.
The reason for the low success rates and significant collateral damage in treating geriatric depression is that most psychiatrists are unwilling to adopting an evidence-informed stepped-care approach. Most practitioners were drawn to psychiatry because they are kind, empathic people who enjoy listening to their patients. They try to match their first-line antidepressant to the patient’s individual clinical characteristics or circumstances. As a result, they do not gain extensive clinical experience with any given medication, they don’t exude confidence in its use, they make ill-timed changes in treatment, and they are susceptible to the latest "fad du jour."
I use a treatment algorithm. That’s the one I would use for my 85-year-old mother if she got depressed, and if it’s good enough for my mother, it’s good enough for my patients. I’m going to use this treatment algorithm in patients I’ve not yet met and I’ve not yet talked to. By not trying to match a specific treatment to an individual patient, I believe that I will be able to get 60%-70% of those people better. And if they don’t give up and stay in our clinic for a year through up to three or four treatment trials, if need be, we’re going to help about 90% of those older depressed patients.
In the landmark PROSPECT study (Prevention of Suicide in Primary Care Elderly: Collaborative Trial), my coinvestigators and I developed and used one such treatment algorithm (Int. J. Geriatr. Psychiatry 2001;16:585-92). This particular algorithm resulted in faster improvement and a significantly higher 24-month remission rate than did usual care in randomized depressed patients (Am. J. Psychiatry 2009;166:882-90), but there are other stepped-care algorithms of proven benefit (J. Clin. Psych. 2005;65:1634-41). Each step utilizes a medication with a different mechanism of action. In a meta-analysis of studies on treatment-resistant depression, sequential treatment – that is, a stepped-care approach – was what worked best, with an 88% response rate (Am. J. Psychiatry 2011;168:681-8).
Everyone in medicine is aware that poor patient adherence to prescribed medications is a big problem. That’s particularly true in late-life depression. The secret to high treatment response rates in geriatric depression is to convince the patient to fill the prescription, take the drug as prescribed, and stay on it despite initial side effects or lack of efficacy. A psychiatrist who follows a treatment algorithm is able to be more convincing in this regard because of more extensive experience with a given drug.
A negative randomized clinical trial of citalopram for the treatment of geriatric depression is a good illustration of a dirty little secret about psychopharmacology: Where a patient gets treated – that is, the way psychiatrists at that site use the drug – matters more than the drug itself does. In this 15-site clinical trial, the response rates to citalopram ranged by site from a low of 18% to 82%, while the response to placebo ranged from 16% to 80% (Am. J. Psychiatry 2004;161:2050-9).
Dr. Benoit H. Mulsant is professor of psychiatry at the University of Toronto and physician in chief at the Center for Addiction and Mental Health, Toronto. This editorial is adapted from his presentation at the annual meeting of the American Association for Geriatric Psychiatry. Dr. Mulsant reported that his research has been supported predominantly by the National Institute of Mental Health (with medications for NIMH-funded clinical trials provided by Bristol-Myers Squibb, Eli Lilly, or Pfizer), and he declared having no other financial conflicts.