There is some evidence for benefit from alpha-blockers and antibiotics, and for anti-inflammatory drugs in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), however it is generally weak, and effect sizes small.

CP/CPPS is a common but poorly defined clinical condition that impairs function and has significant impact on patients’ quality of life; it is diagnosed by exclusion and its cause is unknown. Many different treatments are used, but their efficacy is unclear as clinical trials that have tested them have been too small to demonstrate efficacy reliably. The authors of this review aimed to compare outcomes and determine response rates with tested drug using network meta-analysis. Treatment comparisons included total symptom, pain, voiding, and quality-of-life scores at the end of therapy with alpha-blockers (the most commonly evaluated therapy for CP/CPPS), other active drugs, or placebo. They carried out a systematic literature search using the two major biomedical databases, from database start (MEDLINE from 1949, EMBASE from 1974) to mid November 2010.

Study selection criteria were: confirmed CP/CPPS; comparison of any pair of the following interventions (alpha-blockers, antibiotics, steroidal and nonsteroidal anti-inflammatory drugs, finasteride, glycosminoglycans, phytotherapy, gabapentinoids, and placebo); measurement of any of the selected outcomes; and availability of the full article with sufficient data for extraction. Pooled standardised or unstandardised (as appropriate) mean differences (SMD / USMD) and response rates (as relative risk, RR) were calculated for direct comparisons and network meta-analysis was used to derive indirect comparisons as RR and 95% CI.

The initial search yielded 328 potentially relevant articles, of which 30 were retrieved for full review (main reasons for exclusion, not CP/CPPS and duplicate publication). On full review, there were 5 not relevant and 2 with insufficient detail, leaving 23 articles for analysis: 20 of these compared one drug with placebo and 3 had more than 2 treatment arms. Interventions most often studied were alpha-blockers, antibiotics, anti-inflammatory drugs, and phytotherapy.

In direct comparisons, alpha-blockers were associated with statistically significant improvements compared to placebo in total symptom score (SMD −1.7; 95% CI, −2.8 to −0.6), pain score (SMD −1.1; 95% CI, −1.8 to −0.3),, voiding score (SMD −1.4; 95% CI, −2.3 to −0.5), and quality-of-life score (SMD −1.0; 95% CI, −1.8 to −0.2). Patients receiving alpha-blockers or anti-inflammatory medications had a higher chance of favourable response compared with placebo, with pooled RR of 1.6 (95% CI, 1.1-2.3) and 1.8 (95% CI, 1.2-2.6), respectively. Network meta-analysis suggested benefits for antibiotics, with the greatest effect from the combination of alpha-blockers plus antibiotics.

Funnel plots suggested publication bias in studies of alpha-blockers, and when this was corrected for there was no evidence of treatment benefit. Most trials were small, and in many trials, the risk of confounding by selection bias could not be excluded.

The authors conclude that the evidence suggests alpha-blockers or antibiotics, or combination of the two, as the most appropriate therapy for CP/CPPS. Treatment effects were generally small, however - they note that the accepted minimal clinical significant difference for all the scoring systems used is 3 to 6 points – and there is evidence of publication bias in the studies of alpha-blockers. Other therapies may have beneficial effects on particular symptom areas but require further evaluation. They comment on the apparent benefits of antibiotics in a condition for which exclusion of infection is a diagnostic criterion, suggesting that the benefit may relate to effects on uncultured or unrecognised pathogens or to the known anti-inflammatory and analgesic effects of the quinolones.

[Editor’s note: CP/CPPS is one of a number of conditions termed functional somatic syndromes for which multiple treatment strategies with active patient co-operation are needed for effective management; others include irritable bowel syndrome, chronic fatigue syndrome, multiple chemical sensitivity, non-ulcer dyspepsia, etc. For a comprehensive and fairly recent review, see Lancet 2007; 369: 946-55]