A Meta-Analysis of Randomised Placebo-Controlled Treatment Trials for Depression and Anxiety in Parkinson’s Disease

Abstract

BackgroundPsychopharmacotherapy currently constitutes the first-line treatment for depression and anxiety in Parkinson’s disease (PD) however the efficacy of antidepressant treatments in PD is unclear. Several alternative treatments have been suggested as potentially more viable alternatives including dopamine agonists, repetitive transcranial magnetic stimulation, and cognitive behavioural therapy (CBT).MethodA meta-analysis of randomised placebo-controlled trials for depression and/or anxiety in PD was conducted to systematically examine the efficacy of current treatments for depression and anxiety in PD.ResultsNine trials were included. There was only sufficient data to calculate a pooled effect for antidepressant therapies. The pooled effect of antidepressants for depression in PD was moderate but non-significant (d = .71, 95% CI = −1.33 to 3.08). The secondary effect of antidepressants on anxiety in PD was large but also non-significant (d = 1.13, 95% CI = −.67 to 2.94). Two single-trials of non-pharmacological treatments for depression in PD resulted in significant large effects; Omega-3 supplementation (d = .92, 95% CI = .15 to 1.69) and CBT (d = 1.57, 95% CI = 1.06 to 2.07), and warrant further exploration.ConclusionsThere remains a lack of controlled trials for both pharmacological and non-pharmacological treatments for depression and anxiety in PD which limits the conclusions which can be drawn. While the pooled effects of antidepressant therapies in PD were non-significant, the moderate to large magnitude of each pooled effect is promising. Non-pharmacological approaches show potential for depression in PD however more research is required.

Using Canadian Primary Care Sentinel Surveillance Network data to examine depression in patients with a diagnosis of Parkinson disease: a retrospective cohort study

“…The most frequently prescribed type of antidepressant, SSRIs, is comparable to past American Veteran Affairs studies involving patients with Parkinson disease and depression. 14,15 In addition, depression treatment in the general population shows a high prescribing average (68.0%) of SSRIs in Canadian primary care practices. 18 Possible explanations for this high frequency might be the current general prescription trends and lower adverse effect profile compared with other antidepressants.…”

“…12 Previous work using American Veteran Affairs data examined simultaneous treatment of Parkinson disease and depression. 14,15 Yet, there remains limited knowledge as to how these 2 chronic conditions are treated in Canadian primary care or the patient characteristics of those with both Parkinson disease and depression.…”

Prevalence, impact, and management of depression and anxiety in patients with Parkinson’s disease

“…These results were generally consistent with two other recent meta-analyses of pharmacological treatment of depression in PD, suggesting superiority of TCAs to SSRIs in reducing PD depression symptoms. 61,62 In contrast to Troeung et al's 60 findings, Bomasang-Layno et al 59 did not find a significant effect of TCAs in the treatment of depression in PD but found that when stratifying SSRI/SNRI treatments versus other pharmacological treatments, the SSRI/SNRI treatment studies showed a significant effect on depressive symptoms in PD. Of note, Troeung et al 60 also caution that the nonsignificant treatment effect in SSRIs may be due to the limited number of randomized controlled trials (RCTs) included for analysis (N=5) and highlighted the need for additional, carefully designed studies.…”

“…Indeed, several small, controlled trials using selective serotonin reuptake inhibitors (SSRIs) failed to show efficacy in PD depression, although a recent meta-analysis showed significant effect of antidepressant treatment on depressive symptoms in PD when SSRI and serotonin-norepinephrine reuptake inhibitors (SNRI) treatment studies were combined. [57][58][59] Troeung et al 60 recently published a meta-analysis of randomized, placebo-controlled trials for the treatment of anxiety and depression in PD. Of note, this analysis was limited to PD patients who met DSM criteria for depressive or anxiety disorder.…”

“…Of note, this analysis was limited to PD patients who met DSM criteria for depressive or anxiety disorder. Troeung et al 60 found that citalopram, nortriptyline, paroxetine, and venlafaxine showed a small, statistically significant treatment effect in reducing depressive symptoms. In this study, the pooled effect size for studies of tricyclic antidepressants (TCAs) was large and significant (d =1.35, 95% CI =0.19-2.52), whereas the pooled effect size for SSRIs was not significant, again suggesting that different drug classes have variable efficacy in treating depression in PD.…”