"Sleep Apnea as a Cause of Gout Flares", a Letter published in Medscape journal , is a recycling of the hoax made earlier in Sleep journal . The following explains why ref.  is a hoax.
1) In ref. , the Author states: "Pulmonology journal literature [1,2] describes 2 mechanisms by which the hypoxemia of sleep apnea leads to MSU precipitation." The facts are: refs. [1,2] do not contain words: "gout", "hyperuricemia", "MSU", "monosodium urate", and "precipitation". And, they do not state, imply, or discuss that "sleep apnea leads to MSU precipitation". How these two references can be stretched out so much to mean "sleep apnea leads to MSU precipitation" is beyond anyone's imagination.
2) In ref. , the Author also states: "Other pulmonology journal literature has confirmed that hyperuricemia is a result of sleep apnea. [3–5]". Again, this statement is pure fabrication and is false because:
* Refs. [3-4] re-confirm the well-known fact that obesity causes both hyperuricemia and sleep apnea. They do not show sleep apnea alone causes hyperuricemia and gout.
* Ref.  shows that the mean uric acid concentration of 1,135 patients suspected to have sleep apnea is in normal range (6.31 mg/dL) -- i.e., sleep apnea does not cause hyperuricemia. Therefore, sleep apnea alone cannot cause gout.
So, where is the proof that "sleep apnea leading to the precipitation of MSU..." ? The answer is: nowhere. Why then the Author publishes ref. ? It appears that the purpose of the Letter to the Editor of Medscape  is to recycle the hoax started in ref.  to publicize the Author's imaginary "personal discovery" under the covers of the five unfairly mis-represented references.
. Grum CM. Cells in crisis: cellular bioenergetics and inadequate oxygenation in the intensive care unit. Chest. 1992;102:329–330. [PubMed]
]2]. Hasday JD, Grum CM. Nocturnal increase of urinary uric acid:creatine ratio: a biological correlate of sleep-associated hypoxemia. Am Rev Respir Dis. 1987;135:534–538. [PubMed]
]3]. Plywaczewski R, Bednarek M, Jonczak L, Górecka D, Sliwiñiski P. Hyperuricemia in males with obstructive sleep apnea (OSA) [in Polish] Pneumonol Alergol Pol. 2005;73:254–259. [PubMed]
. Plywaczewski R, Bednarek M, Jonczak L, Górecka D, Sliwiñiski P. Hyperuricemia in females with obstructive sleep apnea [in Polish] Pneumonol Alergol Pol. 2005;74:159–165. [PubMed]
. Ruiz Garcia A, Sanchez Armenqol A, Luque Crespo E, et al. Blood uric acid levels in patients with sleep-disordered breathing [in Spanish] Arch Bronconeumol. 2006;42:492–500. [PubMed]
 Sleep Apnea as a Cause of Gout Flares. Burton Abrams, Medscape J Med. 2009; 11(1): 3.
 Gout is an indicator of sleep apnea. Abrams B., Sleep. 2005 Feb 1;28(2):275.