The goal of this clinical trial is to learn if positive airway pressure (CPAP) therapy works for blood pressure (BP) control in obstructive sleep apnea (OSA) adult patients plus undiagnosed hypertension (HBP), using a cuffless bracelet for continual optical BP monitoring (AKTIIA OBPM).

It will also learn if CPAP improves cardiac function in these patients using speckle tracking echocardiography (STE) and to learn about ease of use and patient experience with AKTIIA device and AKTIIA OBPM.

The main questions it aims to answer are:

• Does CPAP reduce systolic BP (and other BP metrics) in this population?
• Does CPAP improve cardiac function in the same population? Researchers will compare BP metrics derived from AKTIIA OBPM and STE metrics in a before and after CPAP therapy to evaluate its therapeutic effect.

Participants will:

• Take a CPAP titration and telemonitoring program for 12 weeks (from the titration date)
• Take an AKTIIA OBPM one week before CPAP and 12 weeks since CPAP titration date
• Take a STE test twice, before starting CPAP and 12 weeks after CPAP titration date
• Take an online survey about easy of use and patient experience with AKTIIA OBPM device

Patients with moderate-severe OSA, indication for CPAP therapy and undiagnosed hypertension will be included. If the patient meets all the inclusion criteria and none of the exclusion criteria, he/she will be considered a candidate for the study. Once the informed consent has been signed, a visit will be made to initiate continuous blood pressure monitoring with the AKTIIA system (AKTIIA OBPM). The first week (week 0, preCPAP) serves to confirm the presence of HBP (average BP 130/80+ mmHg and/or average nocturnal BP 120/70+ mmHg).

If the participant has HBP criteria, an speckle tracking echocardiography (STE) will be performed (preCPAP) and then CPAP treatment will be initiated following the sleep unit´s telemonitoring care program with initial ambulatory pressure titration. If the participant do not have HBP criteria, only CPAP treatment will be started.

The CPAP titration date will be day 1 for AKTIIA OBPM and CPAP monitoring. At 12 weeks of monitoring, a second STE will be scheduled (post-CPAP) and the end-of-study on-site visit is performed to assess: efficacy and adherence to CPAP, clinical and BP control in the AKTIIA OBPM (week 12, post-CPAP).

Finally, an anonymous electronic survey on AKTIIA device usability and patient experience with AKTIIA OBPM and CPAP therapy will be conducted.

Withdrawal criteria are: ineffective CPAP titration, CPAP dropout, invalid AKTIIA OBPM or dropout, prescription of antihypertensive drug, patient decision or PI decision and loss of contact.

Researchers will compare pre-post CPAP blood pressure metrics (systolic BP as the main parameter), circadian profile, dynamic metrics, STE metrics, efficacy and CPAP adherence, symptoms (ESS, QOL own scales) and subgroup analysis by gender, age, OSA severity or CPAP adherence.

Inclusion Criteria:

• Adults 25-70 years old
• Moderate-severe OSA (AHI 15+)
• First prescription of CPAP therapy
• Undiagnosed HBP
• Smartphone use and technological skills
• Informed consent

Exclusion Criteria:

• Antihypertensive drug
• Cardiovascular comorbidity: atrial fibrilation, heart failure, ischemic heart disease, stroke
• Reduced perfusion (e.g. Raynaud)
• Severe/Advanced chronic disease
• Central apnea
• Pregnancy
• Shift work
• Other social issues: misunderstanding/miscommunication

All Individual Participant Data (IPD) that underlie results in a publication

Data requests can be submitted starting 1 month after article publication and the data will be made accessible for up to 24 months. Extensions will be considered on a case-by-case basis.

Data obtained through this study may be provided to qualified researchers with academic interest in sleep apnea, HBP or AKTIIA OBPM. Data or samples shared will be coded, with no protected health information included. Approval of the request and execution of all applicable agreements (i.e. a material transfer agreement) are prerequisites to the sharing of data with the requesting party.

Access to trial IPD can be requested by qualified researchers engaging in independent scientific research, and will be provided following review and approval of a research proposal and Statistical Analysis Plan (SAP) and execution of a Data Sharing Agreement (DSA). For more information or to submit a request, please contact to migueljavier.azpiazublocona@osakidetza.eus