Twenty two RCTs were included in the review (n=4,147 patients).
Continuation antidepressant treatment showed significant beneficial effects for all anxiety disorders assessed, which included: generalised anxiety disorder (RR 0.31, 95% CI 0.25 to 0.38; three RCTS; n=1,342 patients), social phobia (RR 0.39, 95% CI 0.30 to 0.49; four RCTs; n=760 patients), post-traumatic stress disorder (RR 0.35, 95% CI 0.19 to 0.62; three RCTs; n=272 patients), panic disorder (RR 0.44, 95% CI: 0.32 to 0.60; six RCTs; n=796 patients), and obsessive compulsive disorder (RR 0.54, 95% CI 0.45 to 0.66; six RCTs; n=951 patients).
The numbers-needed-to-treat ranged from 3 to 7 across anxiety disorders.
There was no evidence of heterogeneity for any of the anxiety disorders.