The Significance of the influence of Aging and infravesical Obstruction Caused by Benign Prostatic Enlargement on Detrusor impairment

Objective: to analyze the influence of aging and infravesical obstruction on cysto-metric characteristics of patients with lower urinary tract symptoms (LUTS) and proven benign prostatic enlargement (BPE). Methodology: A retrospective analysis was performed of basic characteristics of randomly chosen 213 patients with LUTS caused by BPE and urodynamic findings made in period 2005-2009 at the Urology Department of the Sarajevo University Clinical Center. The patients were divided into groups based on their age (<60 years/46 patients, 60-69 years /95 pat., and >70 years /72 pat.), and the degree of bladder compliance loss (<20 ml/cmH2O-76 patients, 20-40 ml/cmH2O-57 pat., and >40 ml/ cmH2O-80 pat.). All patients had International Prostate Symptom Score (IPS-S) completed, prostate volume measured transabdominally, free uroflowmetry, as well as complete urody-namic study (UDS) findings - cystometry and pressure/flow studies (PFS). The PFS data were plotted on L-PURR, URA and ICS nomogram, bladder contractility index (B CI) and obstruction coefficient (OCO) were calculated for each patient. Results: There was no statistically significant difference of IPS-S, prostate volume and postvoid residual urine among the age groups. Qmax (ml/sec.) declines significantly with age (mean 11.9 vs. 10.3 vs. 7.9, ANOVA p< 0.001), along with statistically significant decrease of cystometric capacity (mean 331ml vs. 293 ml vs. 264 ml, p=0.001), bladder compliance (BC-ml/cmH2O) (mean 35.3 vs. 31 vs. 26.5, p=0.013), with increased incidence of detrusor overactivity (DO) (21.7% vs. 32.6% vs. 45.8%, chi2 test for trend p=0.006), followed by a higher incidence of obstruction (URA>29 cmH2O) (37% patients vs. 61% patients vs. 72.2% patients Chi2 for trend=13.8; p=0.0002), along with noticeable reduction of BCI (117 vs. 121 vs. 106; p=0.02). Patients with severe BC damage (<20 ml/cmH2O) showed a difference with respect to the degree of obstruction and age, along with decreased cystometric capacity and higher incidence of DO, while the difference in IPP-S was insignificant. OCO with cut-off point of 1 showed significant difference with regard to age (66.3 vs. 66.6 years, T test, p=0.015), prostate volume (45 cc vs. 51.8 cc, p=0.007) and incidence of DO (26% vs. 43.4%, p=0.02). Conclusion: the degree of bladder compliance loss and incidence of obstruction increase with age, as reflected in decreased bladder capacity, decreased urine voided volume and increased incidence of D O, along with noticeably impaired detrusor contractility.