Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, University of Utrecht, Heidelberglaan 100, CX Utrecht, The Netherlands.
Department of Clinical Epidemiology, Leiden University Medical Center, Albinusdreef 2, ZA Leiden, The Netherlands.
J Antimicrob Chemother. 2019 Nov 1;74(11):3337-3343. doi: 10.1093/jac/dkz350.
It is unknown whether nitrofurantoin 50 mg normal-release every 6 h (NF50) and nitrofurantoin 100 mg extended-release every 12 h (NF100) are equally effective for treating cystitis in primary care. In the Netherlands, GP prescription of either option largely depends on pharmacy procurement, rather than on patient-related factors.
GP data between January 2013 and July 2018 were retrospectively collected. Inclusion criteria were the use of nitrofurantoin for uncomplicated cystitis, complicated cystitis or cystitis in pregnancy. Criteria for early and late failure were a second antibiotic prescription for cystitis or pyelonephritis within 14 and 28 days post-prescription, respectively. Crude and confounder-adjusted (CA) risk differences (RDs) were estimated using linear regression. Instrumental variable analysis and CA instrumental variable analysis used GP practice proportion of NF50 versus NF100 use as the instrumental variable.
For uncomplicated cystitis (n=46855), treatment with NF50 and NF100 resulted in late failure in 9.7% and 9.6%, respectively. The CA RD, instrumental variable RD and CA instrumental variable RD were 0.2% (95% CI=-0.5 to 0.8), -0.7% (95% CI=-1.7 to 0.3) and 0.0% (95% CI=-0.9 to 1.0), respectively. In complicated cystitis (n=10767), late failure occurred in 10.9% and 11.1% after using NF50 and NF100, respectively [CA RD=0.5% (95% CI=-1.2 to 1.8), instrumental variable RD=-0.8% (95% CI=-3.4 to 1.8) and CA instrumental variable RD=-0.3% (95% CI=-3.0 to 2.4)]. For cystitis in pregnancy (n=1087), NF50 and NF100 resulted in late failure in 13.4% and 7.8%, respectively [CA RD=-5.4% (95% CI=-10.0 to -1.4), instrumental variable RD=-8.9% (95% CI=-16.0 to -1.8) and CA instrumental variable RD=-8.9% (95% CI=-16.0 to -1.7)]. No differences were observed in early failure.
In patients with cystitis in pregnancy, NF100 was associated with a lower incidence of late clinical failure compared with NF50. We found no differences in clinical failure between NF50 and NF100 for uncomplicated and complicated cystitis.
在初级保健中，呋喃妥因 50mg 普通释放每 6 小时（NF50）和呋喃妥因 100mg 延长释放每 12 小时（NF100）治疗膀胱炎的效果是否相同尚不清楚。在荷兰，全科医生处方这两种选择主要取决于药房采购，而不是患者相关因素。
回顾性收集了 2013 年 1 月至 2018 年 7 月的全科医生数据。纳入标准为使用呋喃妥因治疗单纯性膀胱炎、复杂性膀胱炎或妊娠性膀胱炎。早期和晚期失败的标准分别为处方后 14 天和 28 天内再次开具膀胱炎或肾盂肾炎的抗生素处方。使用线性回归估计未校正和校正混杂因素（CA）的风险差异（RD）。使用全科医生实践中 NF50 与 NF100 使用率的比例作为工具变量进行工具变量分析和 CA 工具变量分析。
对于单纯性膀胱炎（n=46855），NF50 和 NF100 治疗后晚期失败的比例分别为 9.7%和 9.6%。CA RD、工具变量 RD 和 CA 工具变量 RD 分别为 0.2%（95%CI=-0.5 至 0.8）、-0.7%（95%CI=-1.7 至 0.3）和 0.0%（95%CI=-0.9 至 1.0）。对于复杂性膀胱炎（n=10767），NF50 和 NF100 治疗后晚期失败的比例分别为 10.9%和 11.1%[CA RD=0.5%（95%CI=-1.2 至 1.8）、工具变量 RD=-0.8%（95%CI=-3.4 至 1.8）和 CA 工具变量 RD=-0.3%（95%CI=-3.0 至 2.4）]。对于妊娠性膀胱炎（n=1087），NF50 和 NF100 治疗后晚期失败的比例分别为 13.4%和 7.8%[CA RD=-5.4%（95%CI=-10.0 至 -1.4）、工具变量 RD=-8.9%（95%CI=-16.0 至 -1.8）和 CA 工具变量 RD=-8.9%（95%CI=-16.0 至 -1.7）]。早期失败无差异。
在妊娠性膀胱炎患者中，与 NF50 相比，NF100 与较低的晚期临床失败发生率相关。我们发现，NF50 和 NF100 在单纯性和复杂性膀胱炎患者中的临床失败无差异。
