Readers of this blog will know that both myself and my son have Obstructive Sleep Apnoea (OSA). My son was diagnosed first which encouraged me to look at my own sleep.
Before realising that I had OSA we'd just assumed that my son's OSA was related to his paralysis, but knowing that one of the risk factors for OSA is having a family member who has it, I imagine that he could well have had OSA anyway and that his paralysis is something that exacerbates it.
I wondered if either of my parents also had sleep apnoea, so I asked them if they'd mind having a simple sleep study in their respective homes in which I'd monitor pulse rate and oxygen saturations (SPO2) along with nasal airflow and the Zeo headband in order to get an idea of their sleep staging.
Relevant histories:
My dad has long complained that he sleeps poorly with frequent awakenings. His wife confirms that he snores loudly regardless of sleeping position. So there is a fair chance that he has Obstructive Sleep Apnoea. Many years ago it was suggested by a doctor that he had narcolepsy without cataplexy (based on symptoms alone, no diagnostic studies were performed) and no more was said about it. He keeps irregular sleeping times and can often wake at 2am and remain awake until morning.
My mum keeps a fairly regular sleep schedule but complains of feeling tired in the mornings. She also describes a feeling of her "throat closing off" as she tries to sleep which repeatedly wakes her. She prefers to sleep prone. She also has high blood pressure which is controlled through medication. Her blood pressure is highest in the mornings. I wondered if these were signs of Obstructive Sleep Apnoea too.
The Results:
I looked at their AHI, and the breakdown of Apnoeas and Hypopneas. Although oxygen saturations alone aren't the "be all and end all" of sleep apnoea, (It's possible to have disrupted sleep and still have respectable saturations), I've included the graphs here for comparison.
To give an idea of what they should look like, here is a recent graph of my son's SPO2 whilst using his BiPAP. His AHI was 0.3:
;)
For more details of his treatment see the "Non Invasive Ventilation" blog post.
My dad had an AHI of 35 (Severe). His oxygen saturations (SPO2) are shown below (they did drop to 53% at times, but I've left the lower scale of the graph at 70% to give a simple comparison between us, but it's clear to see where they dropped below 70%). Some nights that we recorded he had a lower AHI of around 25, so he would be placed in the "Moderate to Severe" category.
;)
My mum had an AHI of 10 (Mild). Her oxygen saturations are shown below. My mum sleeps prone, so I suspect her supine AHI would be higher but the simple monitor that I used didn't measure body position (SPO2, Pleth, Pulse, Airflow only) so I am unable to see if she deviated from a prone position in the night).
;)
My untreated SPO2 (Supine AHI of 15) (Mild to Moderate):
;)
My son's untreated SPO2 (typical Supine AHI of 40) (Severe):
;)
Ideally I'd like to monitor both my parents using Stowood's Black Shadow sleep monitor, to determine sleeping position (and hence Supine AHI - a measurement that I feel is a more reliable indicator) and an audio recording of any snores that take place.
Where now?
My dad doesn't currently feel the need to treat his condition (maybe because he has slept that badly for so long that it seems normal to him). This is a concern because there are so many other conditions that can arise from untreated sleep apnoea but I respect his right to choose. He is retired and doesn't drive so work and car safety aren't issues.
My mum has considered a range of treatments from side-sleeping to dental appliances but after (repeatedly) hearing how much my son and I like CPAP / BiPAP she decided to opt for a CPAP trial. This will take place shortly. We're both intrigued to see if CPAP will have a positive effect on her morning blood pressure along with improving sleep quality.
Based on the fact that so many of my immediate family have sleep apnoea I think that it would be prudent for my daughter to be tested too.