London - The Brexit vote and the election of US President Donald Trump have made many Britons anxious, according to a poll released on Tuesday and mental health charities dealing with the fallout.Relationship counsellors have reported couples arguing over Brexit, while children's support services have said they too have registered calls on the landmark votes.A YouGov survey for the Mental Health Foundation (MHF) found that 49% of respondents reported experiencing some level of anxiety in relation to Trump's election.Some 43% were found to have experienced some degree of anxiety over Britain's vote to withdraw from the European Union.World events"There is a relationship between what happens in the world and how people feel about it. That needs to be taken seriously," said MHF director Mark Rowland.The foundation said it had seen five times as many visitors to its anxiety support page compared to before the Brexit referendum in June, prompting the MHF to commission a survey to see whether the increase could be linked to world events.YouGov surveyed 1 714 British adults online last Tuesday and Wednesday.It found that 29% of people said they had suffered either a great deal or a fair amount of anxiety over Trump, with a further 20% reporting low-level anxiety.The respective figures for Brexit were 20% and 23%. Anxiety develops through a combination of perceived threat, making catastrophic predictions about the future and escalating fear about the implications of decisions or events, Rowland said.Symptoms include difficulty sleeping or controlling breathing, while some people find it harder to conduct their daily lives."We're concerned that people have the tools and the information to prevent it becoming something more serious," he said.The highest results per category experiencing either a great deal or a fair amount of anxiety over Brexit, and also over Trump, were for women, the 18 to 24 age group, Londoners and higher social classes.At the opposite end of the scale, the highest figures for people experiencing not much or no anxiety were found among men, the 65 and over age group, people in Scotland and lower social classes.For some in Britain, the country's decision to leave the EU has been affecting their personal relationships.Quite scaryA survey of 300 counsellors carried out last year by the organisation Relate found nearly a fifth (19%) had seen clients who had mentioned the referendum as an issue in their relationship.Arabella Russell, a Relate counsellor, said some couples would bring up Brexit over fear and uncertainty following the referendum, while others struggled because they voted differently."When it turns out our partner has a different view to us, that can be quite scary," she said.Russell found disagreements over Brexit were usually "the tip of the iceberg", with wider problems at play, while couples who voted the same way were reassured to find one area they agreed on despite arguing about other topics.