Grant: Master's Award: Canada Graduate Scholarships

Insomnia affects between 30 to 60% of cancer patients at any given time. The current gold standard for treating insomnia is cognitive behavioural therapy for insomnia (CBTi), however accessibility to this treatment is limited. Savard and colleagues (2021) recently proposed a stepped care approach to CBTi that would increase accessibility to the treatment by beginning with lower intensity intervention. Although this approach was empirically observed to be equivalent to traditional CBTi, remission rates are still low. The current research aims to understand these low remission rates by uncovering a possible physiological predictor for CBTi response. Low heart-rate variability (HRV) is a marker of parasympathetic functioning that has been associated with risk for insomnia and poorer self-regulation in prior work. Overall, we hypothesize that low initial HRV will predict poorer response to CBTi. In order to test this hypothesis, we will be conducting a secondary data analysis of a recent randomized clinical trial of 177 cancer patients with comorbid insomnia, treated with either stepped care CBTi or standard CBTi. In this study both insomnia severity and HRV data were collected using standard validated procedures. The current research will first test whether patients with lower initial baseline HRV will experience less change in insomnia severity after treatment, which could explain the low remission rates from CBTi in general. We then hypothesize that patients with lower initial baseline HRV will experience less change in insomnia severity after low intensive stepped care intervention compared to those given standard CBTi. Findings from this study may help identify patients most suitable for these low-intensity interventions within a stepped care service delivery approach.