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My partner says he wakes up in the night as he needs to urinate. But could it be that he needs to urinate because he has woken up? (continued)
Maria Gardani
University of Edinburgh, UK
Surprisingly, both explanations can be true. Waking up at night was traditionally attributed to nocturia – frequent nighttime urination. That certainly happens: many people produce more urine at night than their bladder can comfortably hold, especially as levels of the hormone that normally suppresses nighttime urine production decline with age.
But recent research suggests the reverse can be just as common. If something else wakes you first, which can happen at the lighter stages of sleep – a noise, stress, reflux or disrupted sleep cycles – you become aware of your bladder in a way you wouldn’t during deep sleep. Even a moderately full bladder can suddenly feel urgent once you are awake.
This means nocturia isn’t always the root of the problem; sometimes it is a sleep problem in disguise. Sleep apnoea, for instance, can repeatedly disturb sleep and indirectly prompt nighttime trips to the loo. On the other hand, if someone gets up to pass a large volume of urine, the bladder was probably the reason.
In practice, the simplest way to tell is to note what wakes you. If you are aware of waking first and only then deciding to pee – and especially if little urine comes out – broken sleep may be to blame. If the urge itself gets you to wake, the bladder is to blame.
Antero Ranne
Helsinki, Finland
Sometimes I perceive the need to urinate before waking up. I know this because, often, I have been dreaming about trying to find a toilet. On other occasions, I may wake up because of a leg cramp, for instance, and then notice the need to urinate only after getting up.
Gill Elliott
St Albans, Hertfordshire, UK
James Hardy suggests that waking up to wee can be caused by poor daytime choices, such as excess fluids in the second half of the day. However, if I restrict my fluid intake in the evening in order to try to circumvent the 1.30am wee (and the regularity of this suggests a certain amount of habit), I am awoken anyway by a horrendous cramp. It seems I cannot win.
Keith Marwood
via email
For over 30 years, a friend of mine has woken up two or three times in the night to urinate. However, he generally has a dream in which he needs to urinate and goes looking for a toilet, often unsuccessfully. When he finds one, the toilet is bizarrely inadequate in some way. He always needs to urinate badly when he wakes up. Make of that what you will, but I should say that I don’t, er… that is, my friend doesn’t, seem to suffer any adverse effects from this routine.
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