Our review confirms the usefulness of long-term pharmacological treatments for PD and GAD and suggests that they can provide further improvement over that obtained during short-term therapy .
Paroxetine , escitalopram , and clonazepam can be effective for long-term treatment of PD .
Pregabalin and quetiapine can be effective for long-term treatment of GAD , while preliminary suggestions emerged for agomelatine and vortioxetine .
We did not find any evidence for determining the optimal length and /or dosage of medications to minimize the relapse risk .
Many aspects of long-term pharmacological treatments for  anxiety disorders ( AnxDs ) are still debated .
We undertook an up date d systematic review of long-term pharmacological studies on panic disorder ( PD ) , generalized anxiety disorder ( GAD ) , and social anxiety disorder ( SAD ) .
Modeling the longitudinal latent effect of pregabalin on self-reported changes in sleep disturbances in outpatients with generalized anxiety disorder managed in routine clinical practice
Background Anxiety disorders are among the most common psychiatric illnesses , with generalized anxiety disorder ( GAD ) being one of the most common . Sleep disturbances are highly prevalent in GAD patients . While treatment with pregabalin has been found to be associated with significant improvement in GAD-related sleep disturbance across many controlled clinical trials , mediational analysis has suggested that a substantial portion of this effect could be the result of a direct effect of pregabalin . Thus , the objective of this study was to model the longitudinal latent effect of pregabalin or usual care ( UC ) therapies on changes in sleep in out patients with GAD under routine clinical practice . Methods Male and female GAD out patients , aged 18 years or above , from a 6-month prospect i ve noninterventional trial were analyzed . Direct and indirect effects of either pregabalin or UC changes in anxiety symptoms ( assessed with Hamilton Anxiety Scale ) and sleep disturbances ( assessed with Medical Outcomes Study -Sleep Scale [ MOS-S ] ) were estimated by a conditional latent curve model applying structural equation modeling . Results A total of 1,546 pregabalin-naïve patients were analyzed , 984 receiving pregabalin and 562 UC .  Both symptoms of anxiety and sleep disturbances were significantly improved in both groups , with higher mean ( 95 % confidence interval ) score reductions in subjects receiving pregabalin : −15.9 ( −15.2 ; −16.6 ) vs −14.5 ( −13.5 ; −15.5 ) , P=0.027 , in Hamilton Anxiety Scale ; and −29.7 ( −28.1 ; −31.3 ) vs −24.0 ( −21.6 ; −26.4 ) , P<0.001 , in MOS-S. The conditional latent curve model showed that the pregabalin  effect on sleep disturbances was significant ( γ = −3.99 , P<0.001 ) , after discounting the effect on reduction in anxiety symptoms . A mediation model showed that 70 % of the direct effect of pregabalin on sleep remained after discounting the mediated effect of anxiety improvement . Conclusion A substantial proportion of the incremental improvements in anxiety-related sleep disturbances with pregabalin vs UC were explained by its direct effect , not mediated by improvements in anxiety symptoms
Our review confirms the usefulness of long-term pharmacological treatments for PD and GAD and suggests that they can provide further improvement over that obtained during short-term therapy .
Paroxetine , escitalopram , and clonazepam can be effective for long-term treatment of PD .
Pregabalin and quetiapine can be effective for long-term treatment of GAD , while preliminary suggestions emerged for agomelatine and vortioxetine .
We did not find any evidence for determining the optimal length and /or dosage of medications to minimize the relapse risk .
Many aspects of long-term pharmacological treatments for  anxiety disorders ( AnxDs ) are still debated .
We undertook an up date d systematic review of long-term pharmacological studies on panic disorder ( PD ) , generalized anxiety disorder ( GAD ) , and social anxiety disorder ( SAD ) .