Men with spinal cord injury have a smaller prostate volume than age-matched able-bodied men: a meta-analysis of case-control studies

Study design: Meta-analysis Objectives: Denervation and androgen deficiency, peculiar to individuals with chronic spinal cord injury (SCI), could hinder, to some extent, both prostate growth and activity. To comprehensively assess the relationship between SCI and prostate volume, we carried out a meta-analysis of the available case-control studies. Methods: A thorough search of MEDLINE, Scopus and Web of Science was carried out to identify studies comparing prostate volume in men with and without SCI. Quality of the studies was assessed using the Newcastle–Ottawa Scale (NOS). Mean differences (MDs) in prostate volume were combined using a random effect model. Funnel plot was used to assess publication bias. Results: Four studies met the inclusion criteria and provided information on 278 men with SCI and 1385 able-bodied controls. The overall difference in prostate volume between the two groups reached the statistical significance (pooled MD: −14.85 ml, 95% CI: −27.10 to −2.61, p = 0.02). In a subgroup analysis including only the studies with the highest NOS score, the pooled MD remained significant (pooled MD: −18.56, 95% CI: −33.14 to −3.99, p = 0.01). The shape of funnel plot did not allow to rule out a possible publication bias. Conclusions: This meta-analysis suggests that in men with SCI, prostate volume tends to be smaller than in age-matched able-bodied men. Longitudinal studies of men with long-lasting SCI in advanced age are warranted to clarify whether this condition is associated with a lower risk of age-related prostate proliferative diseases.