Anyone who read my previous blog will probably know that I've got a couple of big interests: blows to the head, diabetes, sex (who doesn't?). I've also got a really big interest in both psychiatric disorders such as depression and ADHD, and what scientists like to formally call "drugs of abuse" (it just sounds better than saying "yeah, I study crack"). And this paper combines both psychiatric disorders AND cocaine! Depression on cocaine, it's life really sucking in fast forward.
Levin et al. "Effects of major depressive disorder and attention-deficit/hyperactivity disorder on the outcome of treatment for cocaine dependence". Journal of Substance Abuse Treatment, 34, 2008.
It may come as no surprise to you to hear that psychiatric disorders put people at risk for substance abuse. Drugs of abuse often combat their symptoms, and this is especially evident when you see which psychiatric disorders "go" with which drugs. For example, people with anxiety have a much higher risk of alcoholism than people without. Alcohol is sedative, it's anesthetic, and it's a social lubricant. People with sudstance abuse problems and a co-morbid psychiatric disorder have often been described as "self medicating" for their symptoms.
Here, we're looking at cocaine-dependence. People who are addicted to cocaine very often show up to the clinic with a co-occurring psychiatric disorder. This particular study looked at co-occurrence of major depression and ADHD with cocaine abuse, and how these psychiatric disorders affected the possible outcome of the patients. Interestingly, they didn't actually conduct a specific trial for this, instead they grouped together the placebo groups of three different drug trials for drugs treating cocaine dependence.
No one argues that people with psychiatric disorders such as depression and ADHD are disproportionally represented in drug-dependent populations. In the case of depression, it's got about a 15% occurrence in the population and a 30% occurrence in cocaine-abusers, while ADHD has a 4% occurence in the (adult) population, and up to 25% occurrence in cocaine-abusers. With a co-morbid psychiatric disorder, it's not just about getting them off the crack-habit, it's about treating the psychiatric disorders that may have influenced their drug taking in the first place.
The literature has a couple of opinions on how psychiatric disorders can influence the outcome of cocaine dependence. Some say that treating depression improves measures of cocaine use (which means fewer cocaine-positive urines as opposed to more) (McDowell, 2005).
Improving ADHD symptoms has also been shown to help, at least with the ADHD if not the cocaine abuse, in some clinical trials (Levin et al, 2006), and though it doesn't reduce cocaine use during short term treatment, it can apparently help over time. This isn't too surprising, since ADHD is usually treated with stimulants, and if they're addicted to cocaine, the ADHD treatments might do a little something to reduce the craving. There are currently a whole bunch of ongoing studies that I know of looking at ADHD medications in the treatment of cocaine abuse, even without co-morbid ADHD.
Of course it's really hard to get this kind of data. You might hear a lot about Alcoholics Anonymous, Narcotics Anonymous, and other organizations, but success rates for abstinence are abysmally low. If anyone's ever tried to quit smoking, you'll know what I mean. And smoking has a relatively high success rate (around 15%), due to the prevalence of patches and gum and support groups.
Treatment groups for cocaine don't even have a 50% retention rate, and that's for a program of just a few weeks or months, where they let you keep coming back even if you test positive. Less than 25% of users in a given trial achieve anything like prolonged abstinence, and the probability of relapse is very high.
This is not because the programs are crappy or because the patients are losers. It's because drugs of abuse are incredibly powerful things. The programs do their best, and the patients coming in know how bad they've gotten, and they want to get help and get clean. But cocaine is an insidious thing, and the cravings are often far too powerful for people to withstand. So here's a plug: don't do cocaine. Sure, there's a chance you'll just walk away afterward, no worse for your weekend binge, but do you really want to take the chance that you won't?
Anyway, back to the study. Basically, all of the patients were in placebo groups for 14-week drug trials, trying to get off cocaine, and knowing that they might either get a real drug treatment, or a placebo. They looked at the patients in the placebo group who had depression, ADHD, or no co-morbid disorder, and looked at their retention rates, how many positive urine tests they had, and the substance use outcome.
They found that dropout rates were around 45% in all three groups, no differences there. They also found that only 50% of patients achieved 2 weeks of abstinence, and it didn't matter whether they had a psychiatric disorder or not. So far, no differences.
But what they DID find is that, in patients who managed to become abstinent early on, depression or ADHD actually made for a better prognosis. However, if you were NOT abstinent (continuing to use cocaine in the first week) when you came in and had a co-morbid disorder, you did a lot worse.
What does this mean? Well, we've known for a while that if you start out abstinent when you enter treatment, you've already taken the first step, and your prognosis will be better. Having a psychiatric problem can actually help here. People with depression may seek treatment, because psychological withdrawal from cocaine will make them feel worse, and the same goes for people with ADHD. And if they can stay in the program, their psychiatric symtoms will get better over time (as the withdrawal fades) which may encourage them to see the program through. But if you can't achieve abstinence by the time you walk through the door for the first time, you might as well not have come.
F LEVIN, A BISAGA, W RABY, E AHARONOVICH, E RUBIN, J MARIANI, D BROOKS, F GARAWI, E NUNES (2008). Effects of major depressive disorder and attention-deficit/hyperactivity disorder on the outcome of treatment for cocaine dependence Journal of Substance Abuse Treatment, 34 (1), 80-89 DOI: 10.1016/j.jsat.2006.11.012