OAB score: A clinical model that predicts the probability of presenting overactive detrusor in the urodynamic study

ABSTRACT Purpose To create a predictive model of involuntary detrusor contraction (IDC) to improve the diagnostic accuracy of overactive detrusor (OAD), associating overactive bladder (OAB) symptoms with other clinical parameters in the female population. Materials and Methods A total of 727 women were studied retrospectively. In all of them, urodynamic study was conducted for urogynecological causes. Demographics information, personal history, symptoms, physical exam, a 3-day frequency/volume chart and urinary culture, were collected in all patients and they subsequently underwent uroflowmetry and urodynamic studies. A logistic regression model was performed in order to determine independent predictors of presence of IDC. Odd ratio (OR) estimation was used to assign a score to each one of the significant variables (p≤0.05) in the logistic regression model. We performed a ROC curve in order to determine the predictive ability of the score in relation to the presence of OAD. Results presence of OAD was evident in 210 women (29%). In the logistic regression analysis, independent predictors of OAD were urgency, urgency incontinence, nocturia, absence of SUI symptoms, diabetes mellitus, reduction of vaginal trophism and bladder capacity below 150 mL. The probability of IDC diagnosis increases as the score raises (Score 0: 4% until Score ≥10: 88%). Sensitivity was 71% and specificity 72%. The area under the curve of OAB score was 0.784 (p>0.001). Conclusions OAB score is a clinical tool that shows higher diagnostic accuracy than OAB symptoms alone to predict overactive detrusor.

摘要
研究目的：构建逼尿肌不自主收缩（involuntary detrusor contraction, IDC）预测模型，以提升逼尿肌过度活动（overactive detrusor, OAD）的诊断准确性，将膀胱过度活动症（overactive bladder, OAB）症状与女性人群的其他临床参数进行关联分析。

材料与方法：本研究回顾性纳入727名女性受试者开展分析。所有受试者均因泌尿妇科相关指征接受尿流动力学检查（urodynamic study）。收集所有患者的人口学资料、个人病史、临床症状、体格检查结果、3天排尿频率/尿量记录表以及尿液培养结果，随后所有受试者均接受尿流率检查及尿流动力学检查。为明确IDC发生的独立预测因素，本研究构建了逻辑回归模型。采用比值比（Odd ratio, OR）对逻辑回归模型中具有统计学意义（p≤0.05）的各变量进行评分赋值。通过绘制受试者工作特征曲线（Receiver Operating Characteristic, ROC），评估该评分对OAD的预测能力。

结果：共210名女性（29%）确诊OAD。逻辑回归分析显示，OAD的独立预测因素包括尿急、急迫性尿失禁、夜尿症、无压力性尿失禁（stress urinary incontinence, SUI）症状、糖尿病、阴道营养状态减退以及膀胱容量低于150mL。随着评分升高，IDC的诊断概率逐步上升：评分为0分时概率为4%，评分≥10分时概率升至88%。该评分的敏感度为71%，特异度为72%，OAB评分的曲线下面积为0.784（p>0.001）。

结论：OAB评分是一种临床工具，用于预测逼尿肌过度活动时，其诊断准确性优于仅依靠OAB症状进行诊断的方式。