The very nature of ms is that it is extremely random and variable. A lesion can appear anywhere the CSF is present. I know this is MS 101, but it is very relevant to the research and your question. A lesion can form anywhere, with or without symptom. There is NO pattern. It is just the first lesion(s) to present symptoms that brings you to a doctor. For one patient, it could be their first, while another may have many non-symptomatic lesions before leading to symptoms, leading to "onset" and diagnosis. There are stages of RRMS lesions, inflammatory and degenerative. Inflammatory presents symptoms, and tend to subside. The lesions don't go away, they then start the degenerative process.

Ok...all that elementary MS knowledge being said...

The point in which RRMS is considered to have lapsed into SPMS is defined clinically by the EDSS scale: http://ms.about.com/od/multiplesclerosis101/a/ms_edss.htm Once a patient hits a certain number, I believe it is 5.5 or 6, and no longer goes into remission; they are considered "secondary". However, don't confuse that with a relapse, there are patients who drop to a 6 or 7 on the scale, and post-relapse, are back to a 1 or less.These are very extreme relapses for sure. It isn't defined SPMS until they do not recover, or start to steadily decline. I myself at onset dropped to maybe a 2-2.5, currently-9 years later-I'd be put at maybe a 0.10 or something lol! The only thing stopping me from a perfect exam is the fact that I do in fact have a diagnosis and lesions...

The reason that people who start with onset of motor skills reach spms sooner, is because the EDSS is mainly centered around loss of mobility. And since lesions along the path of motor skills-mainly spinal-have had a chance to "take hold" sooner, it's the natural progression that they become degenerative-or deteriorate-first; since they formed first.

As to the question and "proof" of males reaching SPMS faster, it is a determination of mathematics. It is known that statistically there is a 3/1 female to male ratio. (It's actually more like 4/1). So for example: Say you took 200 patients and track their decline, 150 being female and 50 being male on average. Let's just say for all intents and purposes that 50% of all of these patients have progressed to secondary progressive. You would see that 75 females, and only 25 males have NOT progressed to SPMS. It is this mathematical anomaly that makes it SEEM like men progress more rapidly. You would in fact see less "healthy" males walking around than females by population. My numbers may be a little off, but it's just an example to get to the point. On the same token, you would see more females in worse condition than males. There are just less males in the equation to balance either way. Also, technically speaking, there is an extra, (Ahem..) Functional System that may eventually show disability in males that the gals don't possess. That may tip the "ED"SS scales a bit too. Like I've said since dx..If I can breathe, and "he" works, I'm good....lol!!

These studies were done on DMD-free patients, MS "norm" if you will. There has not been enough time with many of these drugs to give a positive reading on how they effect the overall MS progression spectrum. A lot of it is speculation, but much of it is clinical proof that they are effective. Personally, I take the chance that they work for me, because if I don't take them, I know they Can't. Take care- and from one guy to another, don't believe that bs about male vs. female. You get what you get, try like hell to slow it down, and keep breathing.