1 - (SYM 36) Twelve-month Follow-up: Comparative Efficacy of Cognitive Therapy, Behavior Therapy, and Cognitive Behavior Therapy for Adults with Insomnia

Insomnia is the most common of the sleep and circadian disorders (American Psychological Association, 2013). Unfortunately, insomnia can precede and predict the onset of physical and psychological illnesses, including diabetes (Vgontzas et al., 2009), cardiovascular disease (Sofi et al., 2012), depression, anxiety, and psychosis (Hertenstein et al., 2019). Moreover, insomnia is often persistent and recurrent (Morin et al., 2015). Thus, treatments that alleviate insomnia over the long term are critical. The present study sought to evaluate the relative long-term efficacy of cognitive therapy (CT), behavior therapy (BT), and cognitive behavior therapy (CBT) for insomnia with respect to nighttime and daytime outcomes.

Participants were 188 adults (62.2% female, 81.1% White, 6.5% Hispanic or Latinx, M age = 47.4 years) who were diagnosed with insomnia. They were randomized to eight sessions of CT, BT, or CBT for insomnia. Assessments were conducted at pre-treatment and 12-month follow-up. Multilevel modeling and logistic regression were used to evaluate outcomes of insomnia severity, insomnia response/remission, sleep diary parameters, and daytime functioning.  

Participants in all three treatment groups improved on insomnia severity, sleep onset latency, wake after sleep onset, total sleep time, sleep efficiency, work and social adjustment, and mental health (ps < .05). Moreover, in each treatment group, a substantial proportion of participants achieved remission and response. CBT was associated with larger improvements in insomnia severity relative to CT as well as greater remission and improvements in physical health, relative to CT and BT (ps < .05). For participants with a psychiatric comorbidity, CBT was associated with greater improvements in work and social adjustment and mental health, relative to CT (ps < 0.05). CT was not associated with change in time in bed, and none of the treatment conditions were associated with change in daytime fatigue (ps > .05).

 In summary, all three treatments were associated with improvements in most nighttime and daytime outcomes. Additionally, psychiatric comorbidity moderated few outcomes. These encouraging results suggest that therapists may be able to offer CBT, BT, or CT to improve nighttime and daytime symptoms of insomnia over the long-term, with CBT offering a relative advantage for select outcomes and subgroups. Limitations, implications for clinical care, and future research directions, such as matching CT, BT, and CBT to patients’ needs and preferences, will be discussed.