The number of people being given compulsory treatment under the Mental Health Act rose by 3.5 per cent last year, data has revealed.

The NHS Information Centre found the total figure for detentions in 2009-10 was nearly 50,000, and the year on year increase was the largest in three years. The 50,000 figure includes detentions after admission to hospital and those after removal to a place of safety.

The data also showed the number of formal admissions to hospital under the act rose by 7.3 per cent. In 2009-10, 30,800 people were admitted compared with 28,700 in 2008-09.

Royal College of Psychiatrists lead on mental health law Tony Zigmond said: “[We are] extremely concerned about the large increase in the number of patients being subject to compulsory mental health treatment.”

He said the increase was the inevitable result of some “ill-advised changes” to the Mental Health Act.

Mr Zigmond said: “People who are perfectly capable of making decisions for themselves are having their autonomy overridden.”

In 2008 changes to the Mental Health Act extended the criteria for detention and introduced supervised community treatment orders, under which patients are returned to hospital if they do not continue with treatment on release. In the first year of their use, these orders were given to 6,000 people.

The figures showed admissions to independent sector mental health providers fell between 2008-09 and 2009-10, whereas the admissions to NHS facilities rose.

Mental Health Network director Steve Shrubb said: “Detention in hospital does not necessarily mean ‘failure’ either of community or hospital services and will often be the most clinically appropriate response at a time of acute crisis. Similarly, it is too early to be definite about the effect of community treatment orders and we need to learn from this data.”