[Jerry replies to a question from "Charles"] You wrote that you may have had apnea for 10 years and wonder what damage might have been done before you started treatment.
I assume you meant obstructive sleep apnea, and that you are using some form of CPAP for treatment each night. A related question would be, now that I am being treated, will the damage be halted? will it be reversed?
These are interesting and complex questions. The most important thing to know is that if you have gotten the apnea under control, and continue treatment, you will experience less fatigue, much better overall health, halt any further damage, and possibly enable the reversal of some effects.
Just as the list of effects of apnea is long, so the effects of treatment are many, and the results are various. I have seen research reports on some of the impacts of apnea and there is no general rule about reversal of damage. Some kinds of damage will be halted by treatment, other areas may recover, either immediately or over time. For example, in many instances excessive daytime fatigue and depression respond almost immediately to treatment. For a partial list of signs and symptoms of apnea that will give you an idea of the various impacts of untreated sleep apnea, see http://www.healthyresources.com/sleep/apnea/question/quiz.html
The areas I would want to have answers on would include:
fatigue: is treatment permitting normal alertness during wake?
emotional: was there depression or other abnormal emotional state, and has it resolved with treatment?
blood pressure: was it high before treatment and has it normalized with treatment? (and the correlates of high blood pressure, like heart attack, stroke)
intellectual/pyschological: many dimensions by which psychologists or neurologists assess mental states, capacity for functions like executive function, memory (several aspects), etc. Unless one is tested before apnea, during apnea status but before treatment, and after treatment, it is speculative for an individual.
You might think that scientists would want to know the answers. But doing the research in the American statistical study method has a problem. You would want to take a fairly large number of people and study them at 3 points in time: 1) before symptoms; then on the population that does develop apnea: 2) before treatment and 3) after treatment. This would be a non-trivial and expensive undertaking, and there are ethical issues: since CPAP is such an effective treatment for apnea, doctors can't withhold treatment in order to study the effects of the untreated disease. This is the kind of issue that confronts researchers trying to do a critical evaluation of CPAP treatment: they need to have untreated patients to compare with the treated ones. Other methods of research can be used, but may not have the same methodological strength.
It would be an interesting article to develop an overview, but I haven't done it yet! If you want to pursue it, here's how I would suggest starting.
Our book, Sleep Apnea: the Phantom of the Night gives a broad overview of the mechanisms of sleep apnea and how it affects various systems of the body. That could be the basis for research into results of treatment. http://www.healthyresources.com/sleep/apnea/phantom/index.html
You may get a fair degree of information searching Google, but for reliable info you need to dig down to the professional journals--which are not perfect but the peer review process at least assures you are reading consensus information. (The trouble with the consensus system of peer reviews is that a truly innovative idea may languish). Unfortunately a lot of the journals charge a subscription or per-article fee. You can glean the general trends however by reading abstracts. A great source is free from the NIH, PUBMED:
to start a search http://www.ncbi.nlm.nih.gov/sites/entrez?db=PubMed
free, full text of articles http://www.ncbi.nlm.nih.gov/sites/entrez?db=pmc
An hour or two spent online using these tools will give you a lot of good information, and at least give you a sense of what is known on these issues.
I know this can't really answer your question, but I hope it gives you a context for going forward.