Lower Urinary Tract Dysfunction
Initial management of nocturia

Hector (58 years old)

Hector, 58 years old, works at the national history museum. He complains that he needs to wake up at night several times to void. This started a year ago and he is very tired during the day. He has no significant micturition complaints during the day.


Medical history: Hypertension (amlodipine).
Clinical examination: DRE: normal-sized prostate, not suspicious. Malleolar oedema.
IPSS: 6 (IPSS QoL: 4).
Urinalysis: Normal.
Bladder scan: No post void residual.
Bladder diary: Frequency: day 5x, night 3x. Voided volumes: 100-480 ml. 24h diuresis: 1,560 ml. Nocturnal diuresis: 36% of 24h diuresis. No urgency. No urine leakage.

What is the most likely cause of this patient’s complaint of nocturia?