Studies have shown that obstructive sleep apnea (OSA) can negatively impact cardiac function, especially if the OSA is severe. And studies have shown that treating severe OSA with CPAP can improve cardiac function. However, studies have not shown clearly that treating milder cases of OSA provides significant cardiac benefit.
This study looked at patients with mild-to-moderate OSA with mild cardiac dysfunction. Patients were minimally symptomatic with regards to OSA as well. Patients were either given CPAP for 6 months or given no CPAP. Compliance with CPAP was determined based on the CPAP download. The results did not show any convincing change in cardiac function or structure after 6 months of CPAP usage. There was no dose response effect with CPAP usage either, meaning that there still was no change in cardiac function in those that used CPAP the longest per night.
The researchers concluded that CPAP use in patients with mild OSA and mild cardiac dysfunction may not be as helpful as traditional cardiac dysfunction treatments like blood pressure medications.