Insomnia and Susceptibility to Depressive Symptoms and Fatigue in Diverse Breast Cancer Survivors

Background: Nearly 40% of breast cancer survivors have insomnia, yet, information how this condition affects their quality of life is lacking. We examined the association between insomnia and depressive symptoms and fatigue in breast cancer survivors. Methods: Participants were recruited from a community health plan. We conducted a cross-sectional analysis to examine the association between current insomnia (using Insomnia Severity Index [ISI]) and current depressive symptoms (using Inventory of Depressive Symptomology [IDS]) and fatigue (using Fatigue Symptom Inventory [FSI]) in 315 breast cancer survivors who did not have major depressive disorder. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using multivariable logistic regression. Results: The cohort included 30% minority women whose median time since breast cancer diagnosis was 6 years. Survivors with current insomnia symptoms (ISI ≥8) had a sixfold greater odds of current depressive symptoms (IDS >14, OR = 5.98, 95% CI: 3.04–11.76), after adjusting for lifetime insomnia history (OR = 2.01, 95% CI: 1.03–3.94) and perceived stress (OR = 6.37, 95% CI: 2.48–16.32). Insomnia symptoms were markedly associated with moderate fatigue (FSI >3, OR = 5.02, 95% CI: 2.66–9.44). Ever use of antidepressants or sleep medications post-breast cancer diagnosis was not associated with lower odds of current depressive symptoms or feeling fatigued in those with insomnia symptoms. Conclusion: Current insomnia symptoms were strongly correlated with current depressive symptoms and fatigue. Survivorship care plans should consider incorporating insomnia screening to that may potentially enhance quality of life domains.