AIMSThe purpose of this study was to evaluate lower urinary tract symptoms (LUTS) in idiopathic normal pressure hydrocephalus (iNPH). METHODSPatients with new-onset iNPH were prospectively evaluated for LUTS via detailed history and physical, and administration of questionnaires from the International Consultation on Incontinence to assess incontinence (ICIq-UI), overactive bladder (ICIq-OAB), and quality of life (ICIq-LUTqol), as well as the American Urological Association Symptom Score bother scale. All patients with moderate-to-severe LUTS were offered urodynamic testing. Sub-analysis was performed based on gender, medical comorbidities, and age. RESULTSFifty-five consecutive patients with iNPH completed the initial evaluation and surveys. Total urinary incontinence score was mild to moderate (8.710.64: 0-21 scale) with 90.9% experiencing leakage and 74.5% reporting urge incontinence. The most common OAB symptom was nocturia (2.2 +/- 0.14: 0-4 scale) with urge incontinence the most bothersome (3.71 +/- 0.44: 0-10 scale). Quality-of-life impact was moderate (4.47 +/- 0.4: 0-10 scale) and American Urological Association Symptom Score bother scale was 2.89 +/- 0.22 (0-6 scale). Urodynamics testing revealed 100% detrusor overactivity and mean bladder capacity of 200mL. Several differences were identified based on gender, medical comorbidities, and age. CONCLUSIONSPatients with iNPH present with mild-moderate incontinence of which nocturia is the most common symptom, urge incontinence the most bothersome, with 100% of patients having detrusor overactivity. Younger patients experienced greater bother related to LUTS. To our knowledge, this is the only prospective evaluation of urinary symptoms in patients with new-onset iNPH.