SCOTTSDALE, ARIZ. – Most physicians who treat alcohol-dependent patients know that studies have shown that depressed patients are much less likely to quit, or reduce, their drinking.
It is less well known that treating depression in these patients can improve alcohol treatment results, Dr. Edward V. Nunes said at the annual meeting of the American Academy of Addiction Psychiatry. “The evidence shows if you do careful diagnosis–preferably in the setting of abstinence, but not absolutely so–treatment works,” said Dr. Nunes, research director at the Substance Treatment and Research Service, New York.
Until fairly recently, treating depression in alcoholic patients has not been a standard practice, because researchers have had difficulty proving that it had any benefit, said Dr. Nunes, who reviewed the history of the research. Studies conducted before the 1980s were mostly inconsistent, largely because of the absence of a standardized diagnosis for depression that differentiated the depressive effects of heavy alcohol use from primary depression in a person abusing alcohol, said Dr. Nunes, who also is a psychiatrist at the New York State Psychiatric Institute.
Then the use of selective serotonin reuptake inhibitors (SSRIs) came into practice. But studies with SSRIs were generally seen as disappointing. Researchers interpreted study results to mean that the drugs appeared to reduce drinking behavior but had little impact on mood.
One study even suggested that SSRI treatment might increase drinking behavior in individuals with early onset alcoholism. So, for a while it was thought that depression treatment was irrelevant to people seeking help with an alcohol problem.
A study conducted by Dr. Nunes helped rekindle the idea of addressing depression in alcohol abusers. He gave imipramine to a group of alcoholic patients who appeared to have depression. He then continued the study with the patients who responded to the treatment to potentially identify only those who had a true primary depression. These patients were randomized to continued treatment or to placebo. Patients who were switched to placebo tended to get worse and relapse, whereas, those who remained on imipramine continued to respond (Am. J. Psychiatry 1993;150:963–5).
The study has since been replicated, without the first phase, using instead a newly available diagnostic tool that helps identify primary depression from alcohol-induced depression, he said (Arch. Gen. Psychiatry 1996;53:232–40).
The more recent study suggested a response rate of 50% with imipramine treatment, compared with 25% for patients on placebo. Though the number of patients who achieved complete abstinence from alcohol was low, the study was able to show that drinking decreased and that mood was correlated with drinking behavior.
Recently, Dr. Nunes conducted a literature review and an analysis of 14 of the most rigorously conducted trials of depression treatment in substance abusers (mostly alcoholics), out of the 44 placebo-controlled trials identified in the review (JAMA 2004;291:1887–96).
Overall, the data from those studies suggest that drug treatment for depression has a significant benefit, as measured by Hamilton Depression Scale scores. Not surprisingly, the benefit is similar in degree to that seen in drug studies for general depression: Fifty percent of treated patients showed improvement, compared with 30% of placebo controls.
Deeper analysis showed that the six studies that failed to show a benefit from treatment tended to have high placebo response rates, in the range of 40%–60%. This suggests that perhaps the placebo response masked the true response.
These six studies also tended to have patients receive structured alcohol treatment psychotherapy, which probably alleviated some depression and increased the placebo-response rate, Dr. Nunes said.