The impact of nocturnal polyuria in older people with nocturnal LUTS

BACKGROUND: Bladder dysfunctions often express the presence of lower urinary tract symptoms (LUTS) and are common in older people. The aim of this study was to analyze the micturition, incontinence and residual in older subjects, evaluating the role of nocturnal polyuria. METHODS: Eighty-six patients aged 65 or older with invalidating LUTS were hospitalized for 24 hours. The maximum bladder capacity, mean micturition volume, post voiding residual and incontinence volume were recorded and analyzed day-time and night-time. Three groups were defined, i.e. nocturia, nocturnal incontinence and nocturnal polyuria (NP), and patients with or without NP were analyzed. RESULTS: With a majority of female patients 85% and a mean age of 74.3±5.96 years, a high incidence of nocturia (76%) was observed. NP was associated with nocturia in 56 patients (86%). In the three groups, the maximum bladder capacity and mean micturition volume were statistically higher during the night. Patients with nocturia or nocturnal incontinence associated to NP presented with a higher nocturnal maximum bladder capacity and mean micturition volume. A higher nocturnal post-void residual (PVR) was observed in patients with Nocturnal Incontinence associated with NP (P=0.03). Patients without NP presented significantly higher diurnal results. CONCLUSIONS: Nocturnal LUTS in older people is the result of a high nocturnal urine production related to NP with a higher nocturnal bladder capacity. The analyses of micturition, incontinence and PVR, and the accurate evaluation of the presence or absence of NP seems to be the key point for a better therapeutic choice in patients suffering by Nocturnal LUTS.