Treatment Preferences in Patients With Insomnia and Medical Comorbidity: Associated Factors and Impact on Treatment-Outcome.

Insomnia is common in patients with medical comorbidity. First-line treatment for insomnia is cognitive behavioural therapy for insomnia (CBT-I). However, some patients with medical comorbidities prefer pharmacological treatment. This study aimed to (1) identify factors influencing treatment preference in these patients, and (2) assess how aligning treatment with patient preferences impacts outcomes for CBT-I and low-dose Amitriptyline. This study was part of a non-inferiority randomised controlled trial. The study involved 187 participants who were randomly assigned to either CBT-I or Amitriptyline for 12 weeks and 54 participants who refused to participate in the randomised controlled trial. Treatment preferences were assessed at baseline using the Treatment Perception and Preferences (TPP) questionnaire and insomnia severity was assessed before and after treatment with the Insomnia Severity Index (ISI). Multiple and linear regression analyses (p < 0.001, adj. R² = 0.06) revealed that higher age and attributing insomnia to psychological causes predicted a stronger preference for CBT-I while severe insomnia predicted a stronger preference for Amitriptyline. There were no differences in treatment-outcome between amitriptyline and CBT-I for those without a treatment preference, neither for those receiving their treatment preference. However, for patients not receiving their treatment preference, amitriptyline performed significantly worse than CBT-I (M = 13.72 (1.72) vs. M = 9.83 (0.80), p = 0.045). In conclusion, age, attributing insomnia to psychological causes and insomnia severity predict treatment preference in patients with medical comorbidity. Our findings suggest that when treatment does not align with a patient's preference, CBT-I results in a better treatment-outcome than medication. Trial Registration: Dutch Trial Register: NTR NL7971.