Stephen Fry attempted to kill himself while filming abroad last year.
He has bipolar disorder. It is a condition in which suicidal thoughts and attempts to take your own life are common themes.
There are suggestions that at least a quarter and maybe even half of patients make at least one attempt.
Deaths from suicide are higher in people with bipolar disorder. A study following 2.5 million people in Denmark for four decades showed the scale of the issue.
During that time, 8% of the male bipolar patients and 5% of the female patients died by suicide, compared with 0.7% and 0.3% in the general population.
"It is a big problem unfortunately, the risk is higher than for all the major psychiatric illnesses," said Suzanne Hudson, the chief executive of Bipolar UK.
Bipolar disorder seriously affects mood. There are bouts of mania and depression.
People can go from phases of extreme happiness and creativity to severe depression, including suicidal thoughts.
During his interview, Stephen Fry said: "I am the victim of my own moods, more than most people are perhaps, in as much as I have a condition which requires me to take medication so that I don't get either too hyper or too depressed to the point of suicide."
Ms Hudson said the suicide risk was a "reflection of the extreme mood swings".
"You can fall as low as suicidal depression, but there is also a risk after hypermania when you start to come down and there's a realisation that you're cycling down."
The disorder affects one in 100 people and generally appears in the late teens and early 20s.
Disrupted levels of chemicals in the brain may cause the symptoms of bipolar disorder, but the exact cause is unknown.
Part of the answer is genetic. There is a strong family link, you are more likely to develop bipolar disorder if a close family member has the condition.
Dr Daniel Smith, from the Royal College of Psychiatrists and the University of Glasgow, said drugs and alcohol use contributed to the "dramatic difference" in suicide rates.
"The main problem is it is essentially a depressive illness interspersed with mania or hypomania.
"A major contributor to suicide rates is substance misuse, some struggle with alcohol or drugs, and it is a toxic mixture really in terms of risk factors."
There is no cure for bipolar disorder, but treatments can make it easier to live with the condition.
Daily and long-term mood stabilisers, such as lithium, can reduce the frequency of episodes of mania and depression. There are also specific drugs to tackle the symptoms during an episode.
Psychological treatments to help patients deal with depression and lifestyle advice, around diet and exercise, can also help.
Stephen Fry, who is also president of the charity Mind, said: "The whole point in my role, as I see it, is not to be shy... about the morbidity and genuine nature of the likelihood of death amongst people with certain mood disorders."
He said there was "no reason" for someone wanting to take their own life.
"There is no 'why', it's not the right question. There's no reason. If there were a reason for it, you could reason someone out of it, and you could tell them why they shouldn't take their own life," he said.