There were hundreds of hospital admissions of children and young people following self-harm in Surrey last year, new figures show.
Mental health charity Mind said it is "difficult" to understand how the total number of admissions across England has decreased, as there are still many young people waiting to access mental health support and treatment, and urged the Government to address growing waiting lists.
New NHS England figures show around 630 hospital admissions of people aged between 10 and 24 years because of self-harm were recorded in Surrey the year to March 2024.
It means there were around 281 admissions per 100,000 people of this cohort in the area, which is above the England average of around 267 per 100,000 people.
All local counts are rounded to the nearest five.
Nationally, 27,736 such admissions were recorded in 2023-24. It was down 15% from 32,624 the year before, and the smallest figure since records began in 2011-12.
Minesh Patel, associate director of policy and campaigns at Mind, said: "It’s difficult to know what might be driving these figures, but regardless, we know there is still a long way to go to improve mental health support for young people."
He said there are more than 600,000 young people waiting for access to mental health treatment and support, warning long waits "risk people experiencing a worsening of their mental health, which can increase the need for more complex treatment and support".
He added: "This is all happening at a time when the UK Government has reduced the proportion of NHS spending on mental health.
"All our young people should be able to access timely and quality mental health support, which is why we urgently need a dedicated plan to tackle mental health waiting lists."
The figures also show there was a significant disparity in the rate of admissions between women and men: while 433 per 100,000 women aged 10-24 years old were admitted to hospital because of self-harm last year, this number fell to 104 per 100,000 men.
Alexa Knight, director at the Mental Health Foundation, said young women are "at particular risk" of self-harming, and called on the Government to introduce targeted measure to protect their mental health.
She added although hospital admissions because of self-harm have decreased in England, it is "almost certainly too early to consider this a success", adding fewer admissions does not mean fewer children and young people self-harm.
"Much more needs to be done by the Government to put in place and properly fund the early, community or school-based interventions that help young people not only recover when they are struggling with their mental health, but stay mentally healthy in the first place," she said.
The Department of Health and Social Care have been contacted for comment.