Up to one in five individuals with Parkinson’s disease might be suffering from depression.Depression in Parkinson’s disease (dPD) is associated with poor outcomes. It is related to greater disability, faster pro- gression of physical symptoms, reduced cognitive performance, less ability to care for oneself, poorer adherence to treatment, poorer quality of life (QoL), higher caregiver distress, and increased mortality.What is the best medication to treat dPD?
Fábio L Rocha and team report the results of a meta analysis of double blind RCTs that studied the efficacy of antidepressants in this condition. Response (reduction of at least 50% in baseline symptoms on a depression scale) and remission (a score of seven or less on the 17 items of the Hamilton Depression Rating Scale (HDRS) or a score of 10 or less on the MADRS were the main outcomes.
Only seven trials satisfied the pre-established inclusion criteria. (Akça et al., 2011; Andersen et al., 1980; Devos et al., 2008; Leentjens et al., 2003; Menza et al., 2009; Richard et al., 2012; Wermuth et al., 1998 .Wermuth et al. study was excluded from main analysis as it had limiting methodological problems.
The duration of the studies varied from 4.5–12 weeks. The mean age of participants varied from 62–69 years. Trials included 6 SSRIS (two sertraline, two citalopram, and two paroxetine), two SNRI (venlafaxine), and two tricyclic (desipramine and nortriptyline) agents.
SSRIs were superior to placebo in only two of the five studies with this comparison. Tricyclics were superior to placebo in both studies in which this was investigated .Venlafaxine was superior to placebo in the only trial with this comparison.
When the five placebo-controlled studies were taken together, the overall RR (risk ratio) for response was 1.36 (confidence interval (CI): 0.98, 1.87), indicating no statistically significant superiority of antidepressant over placebo treatment. However, when the study with significant methodological problems was ( Wermuth et al.) excluded, the overall RR for response was 1.41 (1.01, 1.96)( ie significant benefit).The crude response rate for antidepressants was 45.5% versus 30.7% for placebo .This is similar to response rate in treatment of depression occurring in the context of chronic physical health problems
Taking all five placebo-controlled studies together, antidepressant medications are not efficacious in dPD. When the study with questionable results was excluded, antidepressants were significantly effective. There were no differences between classes of medication.
Limitations: Small number of trials, patients included in the trials were not always representative of patients in clinical practice, agents like Mirtazapine and Bupropion were not studied.
Conclusion: Antidepressants may be effective in dPD.
Summary of the article:
Antidepressants for depression in Parkinson’s disease: systematic review and meta-analysis. Rocha FL, Murad MG, Stumpf BP, Hara C, Fuzikawa C. J Psychopharmacol. 2013 May;27(5):417-23