Impact of sleep on complicated grief severity and outcomes

Background Complicated grief (CG) is characterized by persistent, impairing grief after losing a loved one. Little is known about sleep disturbance in CG. Baseline prevalence of subjective sleep disturbance, impact of treatment on sleep, and impact of mid-treatment sleep on CG and quality of life outcomes were examined in adults with CG in secondary analyses of a clinical trial. Methods Patients with CG (n = 395, mean age =53.0; 78% female) were randomized to CGT+placebo, CGT+citalopram (CIT), CIT, or placebo. Subjective sleep disturbance was assessed by a grief-anchored sleep item (Pittsburgh Sleep Quality Index: PSQI-1) and a four-item sleep subscale of the Quick Inventory of Depressive Symptomatology (QIDS-4). Sleep disturbance was quantified as at least one QIDS-4 item with severity >= 2 or grief-related sleep disturbance >= 3 days a week for PSQI-1. Outcomes included the Inventory of Complicated Grief (ICG), Work and Social Adjustment Scale (WSAS), and Clinical Global Impressions Scale. Results Baseline sleep disturbance prevalence was 91% on the QIDS-4 and 46% for the grief-anchored PSQI-1. Baseline CG severity was significantly associated with sleep disturbance (QIDS-4: p = .015; PSQI-1: p = .001) after controlling for comorbid depression and PTSD. Sleep improved with treatment; those receiving CGT+CIT versus CIT evidenced better endpoint sleep (p = .027). Mid-treatment QIDS-4 significantly predicted improvement on outcome measures (all p < .01), though only WSAS remained significant after adjustment for mid-treatment ICG (p = .02). Conclusions Greater CG severity is associated with poorer sleep beyond PTSD and depression comorbidity. Additional research including objective sleep measurement is needed to optimally elucidate and address sleep impairment associated with CG.