A variety of factors, including age at injury and type of bladder drainage, appear to influence the risk of urinary stone formation in men with spinal cord injury, Korean researchers report in the April issue of the British Journal of Urology International.
Dr. Hong B. Shim of Seoul Veterans Hospital and colleagues note that recent medical advances have greatly increased survival in such patients. However, they are prone to urological complications, particularly stone formation.
To help characterize underlying factors, the researchers retrospectively examined data on 140 men who were injured before 1987. Over 17 years, 39 patients (28%) developed bladder stones and 21 (15%) developed renal stones.
Analysis showed that patients who were 24 years of age or more when injured were significantly more likely to have bladder stones (odds ratio 2.5) than those who were injured when they were younger.
Findings in another model showed that patients with complete injury were at greater risk of renal stone formation (odds ratio, 4.1) than those with incomplete injury.
Renal stones were also significantly more likely in those with neurogenic bladder using indwelling urethral catheterization (odds ratio, 5.7) than in patients who voided spontaneously. The risk was not significantly increased with clean intermittent catheterization or suprapubic cystostomy.
Renal stones were also more common in patients with bladder stones (odds ratio, 4.7).
The researchers acknowledge that the study was retrospective, but Dr. Shim told Reuters Health, “in men unable to use intermittent catheterization or who are unable to void spontaneously, suprapubic cystostomy is better than urethral catheterization to avoid renal stone formation.”