Clinical utility of urinary microRNA (miR-1273g-3p) in male patients with detrusor underactivity

This study aimed to identify urinary microRNAs (miRNAs) as non-invasive biomarkers for pure detrusor underactivity (DU) without bladder outlet obstruction (BOO).

Based on urodynamic study (UDS), patients were classified into non-BOO DU (n = 4), BOO (n = 4), young healthy control (n = 4), and older healthy control (n = 4) groups. Urinary miRNA profiles were analyzed by microarray to identify non-BOO DU-specific candidates. To validate the non-BOO DU-specific miRNA, RT-qPCR was performed in a validation cohort classified into non-BOO DU (n = 16) and BOO (n = 15, BOO or DU + BOO) groups. Diagnostic performance was assessed by receiver-operating characteristic (ROC) curve analysis, and cutoff values were determined. Clinical parameters were compared between groups stratified by the cutoff value.

Microarray analysis identified 28 urinary miRNAs with non-BOO DU-specific patterns in the exploratory cohort; hsa-miR-1273g-3p and hsa-miR-3940-5p were consistently downregulated in the non-BOO DU group in the validation cohort. ROC curve analysis showed an area under the curve (AUC) of 0.804 (95% CI 0.64-0.97) for 1273g-3p and 0.713 (95% CI 0.53-0.90) for 3940-5p. Using the cutoff value of 1273g-3p in the validation cohort, stratification showed no differences in age, BMI, post-void residual urine volume, or prostate volume, but significantly lower bladder outlet obstruction index (p = 0.033) and bladder contractility index (p = 0.021) in the low expression group.

Urinary miRNA profiling may represent a promising non-invasive diagnostic approach for non-BOO DU. In particular, hsa-miR-1273g-3p may be a potential biomarker for identifying patients with non-BOO DU.