Specialist treatment for persistent depression in secondary care: Sustained effects from a multicentre UK study at 24 and 36 months.

Background: Despite the known health costs of persistent depression, there is no established service framework for the treatment of this disorder and a lack of long-term outcome data to inform commissioning. To address this gap, we report the long-term clinical effectiveness of a randomised controlled trial (RCT) testing a specialist, collaborative model of care for people with persistent moderate to severe unipolar depression.

Methods: A multicentre, pragmatic, single-blind, parallel-group randomised controlled trial comparing outcomes from a Specialist Depression Service (SDS) offering collaborative treatment with cognitive behavioural therapy (CBT) and pharmacotherapy for 12 months with treatment as usual (TAU) for persistent, moderate-severe depression in UK secondary care. Participants were initially assessed at baseline, 3, 6, 9, 12, and 18 months, with primary endpoints (17-item Hamilton Depression Rating Scale [HDRS17], and a Global Assessment of Functioning [GAF]) reported elsewhere (Morriss et al., 2016). Additional long-term, post-treatment, follow-up was made at 24 and 36 months with outcomes presented here.

Clinicaltrials: gov (NCT01047124) and ISRCTN registration (ISRCTN 10963342).

Results: At 24 months there remained a statistically significant between-group difference in HDRS-2.69 (-5.14, -0.23) and a non-significant improvement in GAF 2.85 (-1.23, 6.94), both favouring the SDS. Simple statistics are presented at 36 months, due to attrition, showing higher continued response and remission vs TAU across all measures.

Limitations: Potential bias through loss to follow-up, particularly beyond 24 months.

Conclusions: Compared with standard secondary care, SDS management of persistent moderate-severe depression, produced long-term clinical benefits, sustained following treatment completion, suggesting a model for future specialist care.