Historians will long ponder whether David Cameron was correct to turn his back on Europe at last week's summit. But, thanks to one revelation from the weekend, they will also no doubt ask whether he was in his right mind when doing so.

Cameron, it is said, used his tried-and-tested "full-bladder technique" to achieve maximum focus and clarity of thought throughout the gruelling nine-hour session in Brussels. During the formal dinner and subsequent horse-trading into the early hours, the prime minister remained intentionally "desperate for a pee".

Cameron has reportedly used the technique before, notably during his "no notes" conference speeches during the early years of his party leadership. He heard about it when watching a Michael Cockerell documentary about the late Conservative politician Enoch Powell a decade beforehand. Powell – best known for his infamous "Rivers of Blood" speech in 1968 – remarked that he always performed an important speech on a full bladder: "You should do nothing to decrease the tension before making a big speech. If anything, you should seek to increase it."

But it is clear that Cameron is not a keen reader of the journal Neurourology and Urodynamics, otherwise he would know that the medical research on this matter begs to differ. In a somewhat lampooned paper – it won an IgNobel award in September for "improbable research" – Australian and American researchers examined the "effect of acute increase in urge to void on cognitive function in healthy adults". After making eight "healthy young adults" drink two litres of water over two hours, the researchers asked them to complete a series of tasks to test their cognitive performance. They concluded from the results that an "extreme urge to void [urinate] is associated with impaired cognition".

Could it even cause medical problems? Marcus Drake, senior lecturer in urology at the University of Bristol, says: "It's pretty unlikely that this technique would cause a urinary tract infection, but I wouldn't really encourage it."

It leaves a rather unsettling thought: did Cameron inconvenience the UK's relationship with its European allies all for the sake of needing to visit the conveniences?