The effect of first dose of tamsulosin on flow rate and its predictive ability on the improvement of LUTS in men with BPH in the mid-term

Abstract

To investigate if effects of the first single dose of tamsulosin 0.4 mg on uroflowmetry parameters would predict treatment response at the third month. Men over 40 years old with complaints of lower urinary tract symptoms associated with benign prostatic hyperplasia were studied with physical examination, urine and blood analysis, uroflowmetry (UFM), post-voiding residual urine volume (PVR), international prostate symptom score (IPSS), quality-of-life (QoL) index and transrectal prostate ultrasonography (TRUS), and patients with prostate cancer suspicion, past urinary surgery, urinary tract infection and neurologic diseases were excluded. UFM, PVR, IPSS, QoL were repeated at 6th hour of the first day, first month and third month of oral tamsulosin 0.4 mg treatment. All parameters were recorded as baseline, and changes in the UFM parameters, PVR, IPSS and QoL were evaluated in clinical visits. As a total, 48 men (mean 60.17 ± 1.18 years) were recruited. There was a significant increase in maximum urine flow rate (Q (max)) and average urine flow rate (Q (ave)) and decrease in PVR from baseline with the first dose of tamsulosin as well as first and third month of treatment (p < 0.05). IPSS and QoL scores significantly improved at the first month in correlation with UFM parameters. Tamsulosin treatment was effective in 33 (68.7 %) patients at the first administration and 35 (72.9 %) at the third month. Positive predictive value and negative predictive value of Q (max) change at first dose for the third month response rate were 90.9 and 66.6 %, respectively. The mid-term effectiveness of tamsulosin may be predicted by changes in UFM parameters achieved with its first dose.