Severe Nocturia and Low AHI/Low RDI

Hi,

I'm wondering if you all can help me out. I recently moved into elevation (7,200ft) from sea level and have experienced these symptoms as low as 6,000ft. I'll give a summary of the symptoms, some results from a baseline sleep study, and my attempts at solutions. I have a few theories as to what is going on, but I am curious to hear your feedback.

I post here because I am hoping that you all can help me. I am not on a xPAP machine, but given the trouble that I am having, I am hoping to try one out simply for the sake of seeing if it can help.

I appreciate any thoughts you might have.


Symptoms:
• Nocturia:
o At Sea Level: 1x per night; (~7 years) (I'm 25 years old, so this has been since I was 18.)
o At >6,000ft: 3-8x per night; (~9months) Often, it will just be the urge to go that wakes me up. When I first arrived, I thought that this was just a matter of acclimating. It has persisted, however, and is now at the point where I urinate 5x a night and get woken with the urge 1-3x per night (often near the end of my sleeping period – in 15 minute intervals). Note: sometimes I awaken without an urge to urinate, though most often I have a sense that I need to urinate...
• Insomnia:
o At Sea Level: 1-3x per week; Normally, I fall asleep within 10-15m. Occasionally, it takes me longer than 30m. In the past, I had associated the physical restlessness with low blood sugar – thinking that I might have hypoglycemia like my father – so I would eat something and then usually be able to fall asleep. This past fall, however, I tested my blood sugar 2-3x daily and found that my blood sugar stays within a tight range (ruling out hypoglycemia). Of course, some of this has been due to an active mind (getting caught up with a math problem or an idea), but for the most part it has been a physical manifestation of nervousness – almost as if my body refuses to be tired as soon as I lie down.
o At >6,000ft: nightly; Basically, the insomnia that I felt at sea level has been aggravated and has become a nightly phenomenon. I am exhausted, calm, and ready to sleep mentally but my body refuses to fall asleep. This inability to fall asleep has, of course, led to bouts of intense mental energy, but in my experience the causal arrow points from the physical to the mental.
o Note: often I will fall asleep quickly, within 10-15 minutes, but then wake up shortly thereafter and be unable to fall asleep again. This, in fact, happened during my sleep study: I was asleep within 5 minutes, woke up, and then could not fall asleep for another hour. I have had this experience at low and high altitude.
• Headaches:
o At Sea Level: rarely; Aside from dehydration when I was in 2nd grade (which caused a migraine) and a concussion that I got in 6th grade, I have never had a migraine before. Likewise, it is very rare for me to get low-grade headaches in the lowlands – though I have often dealt with a sort of light-headedness that I had associated with low blood sugar.
o At >6,000ft: almost daily; These headaches come in two forms: during the day, I will often have a low-grade headache associated with a sort of light-headedness (which is why I confused it with low blood sugar) and when I wake up at night to urinate, I will often have pain in my head. I have also had 2 severe migraines and 2 lower severity migraines this year. The severe migraines led to numbness in my arms and vomiting. I may have had more migraines, but I have become pretty quick to take an ibuprofen if things are going south.
• Fatigue:
o At Sea Level: rarely; Typically, I have been able to push my body pretty hard. In undergrad, I was on the rowing team (20 hours a week; year round). I have kept active since then and get in a good 1.5 hour workout most days. Most recently, when I was at Portland during the month of January (2017), I was playing basketball 1 – 3 hours every day and spending a lot of time near max heart rate. I did not have much trouble with fatigue and recovery. (Note: during this month in Portland, I returned to my normal 1x nightly urination.)
o At >6,000ft: almost constant; I have not been able to work with the same intensity since I arrived. Even after adjusting for the acclimatization process, there are days where I head up to the gym and either get hit with a headache or just find that I have no energy. I also find myself yawning frequently and with tiredness in my eyelids – though even when I lay down at these times, it is difficult to fall asleep and stay asleep.
• Memory / Focus Impairment:
o At >6,000ft: I find that I am often a bit dazed and light headed, but also that my ability to focus and my memory are impaired. This manifests itself in a lot of small things – forgetting something here or there, finding myself sort of giddy or irritable (as when sleep deprived), etc.

*Recently, I have noticed that my hands tend to be unusually cold some mornings - though this is not a consistent symptom.
*I also have some sort of congestion - very severe - which is not so much mucus as it seems to be pressure. There is not much coming out, but it is very difficult to breathe. Nasal spray seems to help this, but not have much effect on my sleep.

Baseline Sleep Study:

68in tall, 170lbs, BMI of 25.8 - very physically active. Neck Size: 16in

Total Recording Time: 455.4m
Total Sleep Time: 221.5m
Apnea-Hypopnea Index (events/hour): 1.6
Respiratory Disturbance Index: 1.9
Spo2 minutes less than 89%: 1.0

Sleep architecture:
sleep efficiency: 48.6%
sleep onset: 4.0m (I woke up very quickly after this... and in fact do not remember falling asleep for ~1h)
REM latency: 82.5m
Wake After Sleep Onset: 229.9m
sleep staging: N1 - 19.5m (8.8% of sleep time), N2 - 117.5m (53.0%), N3 – 45m (20.3%), REM 39.5m (17.8%)

Respiratory Data: frequency of respiratory events was similar during 6.5 minutes of supine sleep (AHI 0.0) compared to non-supine sleep (AHI 1.7events/hour). REM (AHI 0.0 events/hour) vs. NREM (AHI 2.0 events/hour)

Pulse Oximetry: average oxygen level was 91% during NREM and 91% during REM, with a low of 85%.

Avg. Heart Rate: 41.4 BPM with a low of 29 bpm.

Arousal Statistics: Sleep was normal fragmented with a total of 1 arousals (0.3/hour). There were 0.3 respiratory arousal/hour, 0.0 periodic limb movement arousal/hour, and 0.0 spontaneous arousals/hour.

Periodic Limb Movements: There were 4 PLMs with a PLM Index of 1.1/hour and 0 PLM arousals.

Sleep architecture was remarkable for: short sleep latency, poor sleep efficiency, normal arousal index, decreased REM index.

Note: what is not noted in these statistics is that I had 4 awakenings that I was conscious of during my sleep study. 3 of these awakenings were to urinate – fairly full bladder urinations – and 1 awakening was simply my waking up but trying to not have to go to the bathroom… ie I tried to sleep through the urge to go.

Attempts at Solutions:
Nasal Sprays and Nasal Hygiene, Nasal Dilator Strips, Limiting Water Intake before Bed, Psychological Sleep Hygiene (per Dr. Krakow's book - seems to help some; certainly I have eliminated some bad habits).

I wonder if you have discussed these issues with your doctor? Sometimes symptoms can be indicative of more than one condition, so it's best to be careful about self-diagnosis and self-treatment. If it was me, I'd ask the doctor to review and explain the sleep study data (does this report mean I have sleep apnea? if so, what is the best way to treat it? are there alternative therapies? if not sleep apnea, then what is wrong with me?), and then, because I've never lived at a high altitude, I'd be asking questions about altitude sickness, too (what is it? how does it manifest? does it look like any other medical problems? how is it treated? what happens if it is not treated?, etc.). I do note that your AHI on the sleep study already falls in the "normal" range of less than 5 events per hour, so I wonder why you think an xpap machine would be a suitable treatment option for the symptoms you describe?

That last question is purely rhetorical, though, because I think your best course of action is to seek the advice of your doctor. That person can interpret your symptoms and make recommendations or referrals from a professionally informed point of view. Initial diagnosis is really beyond the remit of forum members here, but there is a wealth of supportive advice for those who have been properly prescribed xpap use and have questions about adapting to life with continuous positive airway pressure. If that turns out to be you, then I hope to see you here again.

All the best to you,
Jean