The author Vladimir Nabokov was almost driven to suicide by psoriasis, a new study has claimed.
The American-Russian writer, best known for his 1955 novel Lolita, reportedly suffered from the common skin condition for decades.
Although it isn't talked about in his novels, Nabokov mentioned the sore and itchy illness in letters to his wife, Vera, between 1923 and 1977 – the year he died.
He describes grim images of bloody underwear, insomnia and flakes of his skin falling from his body onto the carpet.
In 1937 he said 'I'd reached the border of suicide', admitting he was convinced he was losing his mind.
Researchers from the Hôpitaux de Paris in France studied Nabokov's letters and suggest he had particularly bad psoriasis that damaged his mental health.
The incurable condition, which affects around one in 50 people,is caused by the immune system malfunctioning and produces patches of dry, scaly and red skin.
These areas can be very flaky and crusty and may be particularly sore and itchy.
When Nabokov was alive psychodermatology – study of the mental impacts of skin conditions – did not even exist, but it is well established now.
Past research shows between 10 and 58 per cent of people with psoriasis are depressed because of it, and between 2.5 and 7.2 per cent suffer suicidal thoughts.
Nabokov wrote in 1937: 'I'm so tortured by my [psoriasis] now I can tell you straight that [...], I'd reached the border of suicide'.
Nabokov's psoriasis made him extremely itchy, causing insomnia and worsening his mood, something which is not uncommon among people with psoriasis.
He wrote: 'I don't sleep at night because of its furious itchy – and this greatly affects my mood. Sometimes I simply thought I was losing my mind.'
He wrote of 'constant thoughts about my bloody underwear, blotchy mug and the scales pouring down on the carpet'.
In a letter published in the British Journal of Dermatology, researchers suggested a particularly severe flare-up of psoriasis may have been linked to the stress of cheating on his wife.
They add his letters give a useful insight into the psychological effects of psoriasis, improving doctors' ability to treat patients with severe forms of condition.
'Nabokov's psoriasis is known about, but the psychological impact of his condition is not discussed enough,' said Dr Laurie Rousset, one of the researchers.
'His letters paint a vivid picture of a man who was often tormented by the symptoms, social anxiety, and who struggled with shame.
'Nabokov's experiences highlight how important it is that patients feel in control of their condition and are happy with their treatments.'
Daragh Rogerson of the British Association of Dermatologists added: 'Treatments for psoriasis have come a long way since Nabokov's time, as has the availability of psychological support.
'The itching, the insomnia, and the emotional toil of the condition are still common themes raised by patients.
'This is one of the reasons why we launched our support website, Skin Support.
'I hope this powerful testimony will highlight to both doctors and patients the importance of managing the mental aspects of this condition, as well as the physical.'