We read with great interest this article by Balci et al.,Citation1 who described their study of the tamsulosin and nifedipine in medical expulsive therapy (MET) in patients with distal ureteral stone (DUS). The study evaluated the efficacy of 75 patients with a DUS of 5–10 mm diameter in the tamsulosin group (0.4 mg once daily); nifedipine group (30 mg once daily) and diclofenac sodium group (50 mg when required). Their findings showed that tamsulosin group and nifedipine group have a similar stone expulsion rate, and the difference was not statistically significant. However, we have some ideas on this study.
According to their report, the stone expulsion rate in the tamsulosin group and nifedipine group were 76% and 64%, respectively (p = 0.355). However, Ye et al.Citation2 conducted a multicenter, prospective, randomized controlled trial (RCT) of 3189 patients with 4–7 mm stone diameter to compare efficacy of tamsulosin with nifedipine in MET for DUS. They concluded that stone expulsion rate in the tamsulosin group was significantly greater than nifedipine group (95.86% vs. 73.51%; p < 0.01). In addition, the efficacies of tamsulosin and nifedipine have been tested in MET by numerous studies,Citation3,Citation4 and their results have suggested that tamsulosin was more effective than nifedipine in patients with DUS (p < 0.05).
Furthermore, an update meta-analysis was performed to compare nifedipine and tamsulosin as MET for management of DUS by us.Citation5 Our meta-analysis results clearly demonstrated a significant improvement in the stone expulsion rate with tamsulosin relative to nifedipine group (93.4% vs. 72.6%, p < 0.0001). Therefore, we hold that tamsulosin was associated with significantly greater stone expulsion rates than nifedipine in patients with similarly sized DUS (5–10 mm diameter).
However, they found no significant difference in stone expulsion rate between the two groups (p = 0.355). As the authors reported, 75 patients were randomly divided into three groups by different drugs, every group includes 25 patients only. This dose appears to be too small numbers of participants and might have had a significant impact on the evaluation of stone expulsion rate between the tamsulosin and nifedipine group. Hence, we consider it lose statistical power with small sample sizes. Meanwhile, we believe it better to include more high-quality RCTs with large samples.
Declaration of interest
The authors report no conflicts of interest.
References
- Balci M, Tuncel A, Aydin O, et al. Tamsulosin versus nifedipin in medical expulsive therapy for distal ureteral stones and the predictive value of Hounsfield unit in stone expulsion. Ren Fail. 2014;36(10):1541–1544
- Ye ZQ, Yang H, Li H, et al. A multicentre, prospective, randomized trial: Comparative efficacy of tamsulosin and nifedipine in medical expulsive therapy for distal ureteric stones with renal colic. BJU Int. 2011;108(2):276–279
- Gandhi HR, Agrawal C. The efficacy of tamsulosin vs. nifedipine for the medical expulsive therapy of distal ureteric stones: A randomized clinical trial. Arab J Urol. 2013;11:405–410
- Lu Z, Dong Z, Ding H, Wang H, Ma B, Wang Z. Tamsulosin for ureteral stones: A systematic review and meta-analysis of a randomized controlled trial. Urol Int. 2012;89:107–115
- Cao D, Yang L, Liu L, et al. A comparison of nifedipine and tamsulosin as medical expulsive therapy for the management of lower ureteral stones without ESWL. Sci Rep. 2014;4:5254