Excellent question Ward.
1. I lived for years without meds because the early ones (yes, including AZT
...gawd) had serious side effects and, frankly, I felt better without 'em...numbers be damned. It was a quality of life issue.
2. For others, it was a matter of getting treatment if you didn't have insurance or jumping through hoops with a completely unsympathetic public medical bureaucracy (some docs we call "AIDS whores" still don't get it). Stress has a significant effect on the immune system (my bff will attest to that) and, again, the frustrations aren't worth it for some. From the late 80s I saw a lot of friends go downhill pretty quickly because of stress like that and still clearly remember dealing with more than one who'd be angry, sad, etc., never enjoying life. Stress isn't some nice, vague marketing lingo. It has serious, real physiological effects :http://www.thebody.com/content/art32279.html
3. There's also the matter of cost. My current regimen, if I was to purchase it outright, would be $30,000 a year.
4. It may also depend on exactly what someone's specific HIV genome is. And resistance to HIV depends on the individual. Simply, some are more resistant than others.
5. Perhaps I'm stating the obvious, but there can be an element of denial if the person feels fine anyway.
At the risk of rambling - oh wtf - the other side is that delayed treatment may affect outcome. Ugh...my CD4 was down to 33 when I started the current regimen. I'm at 101/4.8% today <---not a typo... and, even at that level, doing relatively well. By way of anecdotal evidence shared with me the other day by a clinician, he'd had a guy in single digits who's doing okay today, despite never being able to get his CD4 above 156.NIH guidelines
make breakpoints at CD4 absolute counts of 350 and 500. CDC adds a breakpoint at <200.
To mix it up, clinicians are using CD4% as a more reliable ongoing indication of immune system health. A good explanation is here
. In short, 40% is about normal, below 25% isn't. lol...I laid a lot on you. But, aside from being a walking petri dish, I'm also a walking encyclopedia.