CPAP & INTRAOCULAR PRESSURE - CONSENSUS OF OPINION

[MCS2014]

A friend of mine had developed severe glaucoma partially due to 10 years of CPAP and is going blind despite multiple surgeries.

 Advanced Intraocular pressure (IOP) reduction is the only known modifiable risk factor and his IOPs are very low, yet he's still losing because the nerve heads are so eroded. Assessments of the optic discs are the best determinant about changes.
 
This is obviously a relevant enough topic and I see previous threads discussing such.
 
Any recent updates as to a consensus of opinion?
 
Here is a study from 2008.

[G. Szabo]

I have been reading medical papers on this issue for a while. One major problem is that you cannot find a medical doctor who is experienced in glaucoma and sleep apnea.

Here is my current understanding:
There is a positive correlation between sleep apnea and glaucoma. However, the cause of this correlation is still unclear. My take is that (i) either the CPAP pressure increases the IOP and worsens the outcomes of glaucoma, or (ii) the lowered oxygen saturation during the suffocation periods (either during CPAP treatment or during untreated apnea) worsens glaucoma.

The best option is to get away with as low a CPAP pressure as feasible without risking the oxygen saturation figure dropping below 90%. Switching to side sleep is the most effective way to reduce the needed pressure.

How to do that when you are not a side sleeper? Use some positional training therapies or instruments. I found all the purchasable straps that force you to turn your side useless. It is because the tennis balls, inflatable balloons, or foam wedges are not staying on your back during your sleep but twist to your side, and you find yourself on your back again.

In my case, the following things worked: I purchased from Amazon a PPE against fall
https://safetyequipment.org/wp-content/u...e-2015.pdf
because it has staps on your shoulders and tights and would not twist easily. I also added more straps going from my left tight to my right shoulder and from my right tight to my left shoulder to make it more stable. I also removed some uncomfortable metal rings. I kept the central back element and tightened a baseball on it. I needed the baseball because I could sleep on my back even when I had a couple of tennis balls fixed to my back.
I had a very positive experience: my pressure was significantly reduced.

I also intend to try the Night Shift / Night-Shift / NightShift instrument this year.
https://nightshifttherapy.com/ns-home/
but it is pricy, and I want to hear first some feedback from our members about its success rate. Would you mind posting your experience with it?
Thanks,
G.

[hydra]

https://pubmed.ncbi.nlm.nih.gov/26376821...le-details

The effect of nocturnal CPAP therapy on the intraocular pressure of patients with sleep apnea syndrome

Purpose: Few studies have documented that nocturnal continuous positive airway pressure (CPAP) therapy is associated with an increase in intraocular pressure (IOP) in patients with severe obstructive sleep apnea syndrome (OSAS). We re-examined the effect of CPAP therapy on the IOP of OSAS patients.

Methods: The IOP of two different groups of newly diagnosed OSAS patients was compared at their first sleep lab exam without CPAP treatment (non-CPAP treated group; n = 20) and at the second sleep lab exam with CPAP treatment (CPAP treated group; n = 31). The sleep lab exam (sleep period: from 11:00 p.m. until 6:00 a.m.) included IOP measurements, a complete ophthalmologic exam, and nocturnal hemodynamic recordings. The IOP was measured serially using rebound tonometer (IOP; ICARE® PRO) performed while in sitting and supine positions before, during, and after the sleep period. We compared the difference in IOP of CPAP and non-CPAP groups.

Results: The mean IOP of the CPAP and non-CPAP groups measured in sitting position before the sleep period was 13.33 ± 2.04 mmHg and 14.02 ± 2.44 mmHg, respectively (p = 0.9). Assuming a supine position for 1 minute significantly increased the IOP by 1.93 mmHg and 2.13 mmHg for both the non-CPAP and CPAP groups (paired t-test; p = 0.02, p = 0.001 respectively), but this IOP rise showed no difference between the two groups. The IOP increased significantly further after 7 hours of sleep in the supine position, and the mean IOP of the CPAP and non-CPAP groups was 19.2 ± 5.68 mmHg and 19.69 ± 5.61 mmHg respectively (independent t-test; p = 0.74). The rise in IOP for both groups was not correlated with any hemodynamic parameters. Three OSAS patients with glaucoma treated with CPAP had mean IOP of 23.75 mmHg after 7 hours of sleep.

Conclusions: OSAS patients have a significant rise in IOP during the sleep period when comparing measurements before and after the sleep period; however, CPAP therapy did not affect the measured IOP. The presented findings suggest that in terms of IOP, CPAP is safe for non-glaucomatous patients, but this may not hold true for glaucomatous patients.

Keywords: CPAP; ICARE® PRO; Intraocular pressure; Obstructive sleep apnea syndrome; Rebound tonometer.

[G. Szabo]

Based on the conclusion of the above paper, the most promising alternative for the glaucoma patients with OSA might be the iNAP instrument (not discussed in the paper!). This device uses negative pressure.

[G. Szabo]

According to some novel findings,  patients with Glaucoma (GLC)  are better off using APAP instead of CPAP or BiPAP. Some might even conclude that it is better not to use any EPR with APAP.

See the Citation below:

Correlation of CPAP, BiPAP, and AutoPAP use with intraocular  pressure in patients with sleep apnea and glaucoma.
Daniel J. Watson B.S.1, Anita Vin M.D.2,and Shuchi Patel M.D.2
1 Loyola University Chicago, Stritch School of Medicine, Maywood, IL
2Department of Ophthalmology, Loyola University Chicago Stritch School of Medicine, Maywood, IL 
  
"• We measured IOPs during PAP therapy with three different machines on patients with GLC and OSA or just OSA. This is the first study to measure IOPs of patients with both GLC and OSA while on PAP therapy.
 
• We report our anticipated results and preliminary data. We expect there to be an increase in intraocular pressure after PAP therapy; AutoPAP machines to increase IOPs the least compared to CPAPs and BiPAPs; and patients with both OSA and GLC to experience the greatest increase in intraocular pressure during PAP therapy."


[b]watson-2.ppt (live.com)[/b]

[EddyDee]

Not sure this is "novel", the study seems to date from 2010, reports "preliminary" findings and includes data from 5 subjects, each with very different CPAP settings.
I couldn't find any peer-reviewed paper which presented the full results of this study.
So frankly I don't think this has much scientific or clinical value.