National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) symptom evaluation in multinational cohorts of patients with chronic prostatitis/chronic pelvic pain syndrome.

BACKGROUND: The assessment of patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) in everyday practice and clinical studies relies on National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) scores for symptom appraisal, inclusion criteria for clinical trials, follow-up, and response evaluation.

OBJECTIVE: We investigated multiple databases of CP/CPPS patients to determine the prevalence and impact of pain locations and types to improve our strategy of individualized phenotypically guided treatment.

DESIGN, SETTING, AND PARTICIPANTS: Four major databases with CPSI scores for nonselected CP/CPPS clinic patients from Canada, Germany, Italy, and the United States.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Individual question scores and subtotal and total scores of CPSI were described and correlated with each other. Ordinal regression analysis was performed to define pain severity categories.

RESULTS AND LIMITATIONS: A total of 1563 CP/CPPS patients were included. Perineal pain/discomfort was the most prevalent pain symptom (63%) followed by testicular pain (58%), pain in the pubic area (42%) and penis (32%); reports of pain during ejaculation and voiding were 45% and 43%, respectively. European patients had a significantly higher number of pain localizations and symptoms compared with North American patients (p<0.001). Severity of pain correlated well with frequency of pain (r = 0.645). No specific pain localization/type was associated with more severe pain. Correlation of pain domain with quality of life (QoL) (r = 0.678) was higher than the urinary domain (r = 0.320). Individually, pain severity (r = 0.627) and pain frequency (r = 0.594) correlated better with QoL than pain localization (r = 0.354). Pain severity categories results for NIH-CPSI item 4 (0-10 numerical rating scale for average pain) were mild, 0-3; moderate, 4-6; severe, 7-10; CPSI pain domain (0-21): mild, 0-7; moderate, 8-13; and severe, 14-21.

CONCLUSIONS: Pain has more impact on QoL than urinary symptoms. Pain severity and frequency are more important than pain localization/type. Cut-off levels for disease severity categories have been identified that will prove valuable in symptom assessment and the development of therapeutic strategies.