The medical condition that can send travel insurance premiums soaring by more than 1,000%

For one medicial condition, insurers increased their prices on average by 715 per cent in the study by Which? - (Getty Images)

Some medical conditions can increase travel insurance premiums by more than 1,000 per cent, research has found.

The consumer champion Which? sought quotes from 12 well-known providers for three real people: a 67-year-old with type 2 diabetes, a 40-year-old with epilepsy, and a 41-year-old with bipolar and personality disorder, who had all had an unplanned hospital admission during the last five years.