Sleep and Arterial Function in Hypertensive Patients With Poor Sleep Quality

Background: Poor sleep quality is associated with increased arterial stiffness, depression, and cognitive decline, all of which contribute to cardiovascular risk in hypertensive patients. This trial tests whether improving sleep through CBT-I can attenuate arterial dysfunction and psychological/cognitive burden. Design: Prospective, single-centre, parallel-group randomised controlled trial with 1:1 allocation, conducted at the Hypertension and Psychiatry Outpatient Clinics of the Unidade Local de Saude Alto Ave (ULSAAVE). Intervention: CBT-I delivered in four weekly 60-minute sessions (sleep hygiene, stimulus control, relaxation techniques), adapted for participants with mild obstructive sleep apnea or comorbid insomnia and sleep apnea (COMISA). Comparator: Passive sleep education (informational leaflets plus non-interactive follow-up calls); control participants are offered CBT-I after study completion. Randomisation and blinding: Computer-generated block randomisation (blocks of 4-6), 1:1 allocation, with allocation concealment via sequentially numbered, opaque, sealed envelopes managed by a third party. Outcome assessors and data analysts are blinded; participants are partially blinded (control presented as an educational intervention). Sample size: 234 participants (117 per group), accounting for 20% attrition, powered (80%, alpha 0.05) to detect a 0.4 m/s between-group difference in pulse wave velocity at 12 months. Analysis: Linear mixed-effects models for repeated measures (time as fixed effect, participant as random effect, group as factor), with baseline apnea-hypopnea index included as a covariate.