Efficacy of an integrative CBT for prolonged grief disorder: A long-term follow-up

Abstract
Background
While some intervention trials have demonstrated efficacy in treating prolonged grief disorder (PGD), data on long-term treatment effects are scarce.
Methods
Fifty-one outpatients with clinically relevant prolonged grief symptoms, who had participated in a randomized controlled trial (RCT), were followed up, on average, 1.5 years after integrative cognitive behavioral therapy for PGD (PG-CBT). Initial assessment procedures were repeated, with PGD symptom severity as the main outcome and general mental health symptoms as secondary outcomes. As results in the immediate and delayed treatment groups (former wait list) were similar, the follow-up data were pooled.
Results
Overall, 80% of the original ITT sample could be reached, that is 89% of the 37 treated participants, as well as 8 out of 14 participants who had dropped out of the RCT. The considerable short-term treatment success of PG-CBT was stable; pre to follow-up Cohen׳s d was large, with 1.24 in the ITT analysis and 2.22 for completers. The pre to post-improvement in overall mental health was maintained.
Limitations
Since the RCT wait list group had been treated after their waiting period as well, no controlled long-term outcomes are available.
Conclusions
PG-CBT proved to be effective in the longer run. In comparison to other RCTs on prolonged grief this is the largest sample followed up for this long.