To compare the prevalence, symptoms, and pathologic changes related to chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) with significant prostatitis-like symptoms between 2 altitude areas in northwest China.

From October 2009 to March 2010 community male residents at 3000 m (Delingha) and 400 m (Xi'An) constituted the population base for the present cross-sectional study. All participants completed a detailed questionnaire containing the National Institutes of Health Chronic Prostatitis Symptom Index, and the subjects who met our definition were invited to undergo clinical evaluation. After screening, the subjects considered to have CP/CPPS were separated into 2 groups: those with type IIIa and those with type IIIb CP/CPPS.

The prevalence of CP/CPPS with significant prostatitis-like symptoms was significantly different between the 2 groups. Moreover, the National Institutes of Health Chronic Prostatitis Symptom Index of patients with type IIIa and IIIb in 2 groups differed significantly, indicating the aggravation of symptoms of CP/CPPS at a high altitude. Additional investigations showed that reactive oxygen species were increased, accompanied by a decrease in the total antioxidant capacity in the expressed prostatic secretions of patients with type IIIa at a higher altitude. In addition, the tumor necrosis factor-⍺, interleukin-8, and interleukin-10 levels in the expressed prostatic secretions of patients with type IIIa in Delingha were increased compared with that in the patients with type IIIa in Xi'An. Notably, the interleukin-6 level in the expressed prostatic secretions was greater in those with type IIIa and IIIb at a higher altitude than in those with type IIIa and IIIb at a low altitude.

At a high altitude, the symptoms of CP/CPPS were aggravated. Oxidative stress and cytokines might involve in the pathologic process and the aggravation of symptoms. In addition, in a high altitude area the pathomechanisms of type IIIa and IIIb CP/CPPS differed.