The aim of this study was to evaluate the correlation between subjective symptoms of Overactive Bladder (OAB) and urinary incontinence (UI) with objective findings obtained through Urodynamic Studies (UDS). The study hypothesized that higher symptom severity scores, as measured by validated questionnaires, would correlate with specific cystometric parameters, such as Detrusor Overactivity (DO) amplitude and Maximum Cystometric Capacity (MCC). Additionally, the study sought to compare clinical and urodynamic profiles across different patient subgroups, including those with neurogenic bladder and those receiving different pharmacological treatments.

This cross-sectional study analyzed data from a sample size adjusted to 120 patients presenting with OAB symptoms. Clinical evaluation included the OAB V8 questionnaire to assess symptom severity and the ICIQ-UI SF to evaluate the impact and severity of incontinence. Demographic data and physical characteristics, including BMI, were recorded. Medical history, comorbidities such as Diabetes Mellitus and neurogenic bladder, and current medications were also documented. All patients underwent UDS to measure parameters including DO amplitude, MCC, compliance, maximum flow rate (Qmax), and post-void residual (PVR). Statistical analysis utilized Pearson correlation coefficients to assess relationships between variables.

The study population consisted of 120 patients with a significant female predominance, totaling 103 women and 17 men. The mean age of the participants was 53.07 years, with a standard deviation of 19.38 years. Regarding physical characteristics, the mean weight was 71.94 kg and the mean BMI was 27.05. Clinical symptom analysis revealed that 47.9% of patients experienced urgency and 63.0% suffered from incontinence. The average 24-hour voiding frequency was 10.96, while nocturia averaged 2.05 voids per night. Urodynamic evaluation showed a mean DO amplitude of 14.73 cmH2O and an MCC of 211.36 ml. Correlation analysis demonstrated that the OAB V8 total score was strongly associated with 24-hour frequency (r = +0.49, p < 0.001) and moderately associated with the ICIQ-UI SF score (r = +0.46, p < 0.001). Notably, the ICIQ-UI SF score exhibited a strong positive correlation with the recorded DO amplitude (r = +0.48, p < 0.05). When comparing subgroups, patients with clinical incontinence had significantly higher OAB V8 scores (32.61 vs. 24.33) and higher DO amplitudes (19.86 vs. 9.71 cmH2O) than continent patients. Furthermore, patients with confirmed DO during UDS had a markedly lower MCC of 200.71 ml compared to 291.33 ml in those without DO. In the neurogenic bladder subgroup, the DO amplitude was substantially higher at 23.33 cmH2O and the PVR was significantly elevated at 140.00 ml compared to 43.15 ml in non-neurogenic cases.

The findings underscore a clear objective-subjective link in OAB pathology. The strong correlation between the OAB V8 score, and voiding frequency validates this questionnaire as a reliable proxy for clinical burden. The relationship between the ICIQ-UI SF score and DO amplitude suggests that patient perception of incontinence severity is directly rooted in the physiological intensity of detrusor contractions. In the neurogenic bladder group, patients exhibited much higher DO amplitudes and dangerously high PVR levels despite reporting fewer symptoms. This indicates that in neurogenic populations, subjective symptoms may under-report physiological risk, as high-pressure contractions and poor emptying pose a threat to the upper urinary tract.

Subjective questionnaires like OAB V8 and ICIQ-UI SF effectively reflect underlying urodynamic abnormalities. However, high DO amplitude and residual volumes, particularly in neurogenic populations, emphasize the necessity of Urodynamic Studies for accurate diagnosis and prevention of complications.

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