Most pipo sabi say Dutch artist Vincent van Gogh get mental health problems - e popularly cut off im left ear and two years later (for 1890) bin kill imself - but e get plenti debate about dia exact nature.

Na complicated task to diagnose patient wey don die, however, and e get many theories about which conditions Van Gogh bin get.

One 2020 study by Dutch academics set out to diagnose im disorders, and dem use nearly 1,000 of im letters as evidence.

Ahead of World Bipolar Day - wey pipo dey mark every year on im birthday (30 March) - BBC tok to one of di authors.

Van Gogh get bipolar disorder?

Vincent van Gogh dey plagued wit different mental health issues from adolescence, and popularly cut off part of im left ear afta e suffer one mental health crisis.

For July 1890, e bin stand for one field outside Paris, and shoot imself. E bin die of im injuries two days later, for age of 37.

E get many competing theories about di exact nature of di artist psychiatric health for di years bifor im self-inflicted death, but one of di most compelling be say Van Gogh get bipolar disorder.

Wetin be bipolar disorder?

- Dis na one mental health condition wey dey affect moods and characterise by one dramatic swing from one extreme to di oda

- Na one common condition, wey dey estimated to affect around one inside 100 pipo

- E get different types of bipolar. Those wey get type I experience periods of manic highs and depressive lows. Those wey get type II experience severe depression and mild manic episodes - wey pipo sabi as hypomania - dat one dey last for shorter period of time. Those wit cyclothymia experience less severe mood swings, but dey fit last longer

- Men and women from all backgrounds dey equally likely to develop bipolar disorder, and although e fit happun for any age, pipo for dia late teens dey particularly vulnerable, as e often dey develop between di ages of 15 and 19

- Each extreme episode of bipolar disorder fit last for somel weeks (or even longer)

Treatments include:

- Long-term medication wey dey known as mood stabilisers to prevent di start of episodes of mania and depression

- Medication to treat di symptoms wen dey happun

- Psychological treatment to help deal wit depression

- Lifestyle advice - like doing regular exercise, improving diet and getting more sleep

Source: UK NHS

Van Gogh bin don dey associated wit bipolar disorder since di theory dey originally expounded for 1938 German book wey di study bin see.

But how we fit dey sure say e get dis disorder rather dan say e dey suffer from oda conditions like schizophrenia, neurosyphilis or poisoning?

Di answer dey for evidence wey e leave behind.

"We dey fortunate to don study almost 1,000 letters wey Van Gogh write to im broda and odas, ova which we don base our conclusions," one of di authors of di 2020 study, di retired professor of psychiatry Willem Nolen of di University of Groningen for di Netherlands tok.

E bin tell BBC say di letters bin give im team di opportunity to look di evidence of symptoms wit view to make diagnosis.

Di authors' intention na to conduct one "broad diagnostic interview" of Van Gogh, di patient, to analyse im psychiatric well-being, even though dey recognise say di painter no write for one doctor, and fit no always don dey entirely honest for im descriptions.

"E fit don exaggerate im symptoms for im letters to im broda sake of say e bin need more moni and more support. But you also fit imagine say wen e bin write one letter to oda family members - including im mama - dat maybe e bin make di symptoms sound less severe," Prof Nolen tok.

Prof Nolen bin go through all di six volumes of letters imself, and three different art historians of di Vincent van Gogh museum for di Netherlands dey interviewed for di study, all experts for di life and work of di painter.

Di conclusion say di study by researchers for di International Journal of Bipolar Disorders draw be say Van Gogh don develop bipolar disorder, wit traits of one borderline personality disorder, wey bin "most likely worsen through alcohol use combine wit malnutrition".

For im lifetime, Van Gogh imself no fully understand wetin dey wrong wit am. E bin write about "mental or nervous fever or madness, I no know quite wetin to tok or how to name am" and first describe am as " one simple artist bout of craziness", possibly to reassure im family.

But di study authors bin find evidence say e bin suffer from depression during adolescence, fulfilled criteria for borderline personality disorder, drink a lot, and commit self-mutilation. But na di indication say e bin go through clear depressive and manic phases wey point to bipolar disorder.

"E no completely clear which form of bipolar disorder wey e bin suffer from sake of say, although im episodes of depression bin clearly dey very severe," Prof Nolen tok, "we no fit tell from di letters whether or not e bin suffer socially from di manic side."

We sabi from im artistic output say e bin get times for Van Gogh life, especially towards di end of im life, where e bin dey very productive, painting portraits and self-portraits, fields and flowers, and di asylum for Saint-Remy where e bin stay for over one year.

Prof Nolen tok say e dey possible say Van Gogh dey paint more wen e bin dey hypomanic state, and dis phase of bipolar disorder sometimes dey associated wit bouts of extreme creativity: one number of well-known celebrities don openly tok about dia own experiences wit di disorder, like Mariah Carey, Demi Lovato, Selena Gomez and Bebe Rexha, as well as one large number of oda musicians, actors and artists - alive and dead - wey don describe am as symptoms wey dey very similar to di condition.

E get equally strong evidence of di depressive phase of di disorder di Van Gogh letters and for art, Prof Nolen tok.

E bin get "at least 10 depressive episodes if not more, and e become more severe despite di fact say e dey hospitalised for psychiatric hospital for over one year".

During di serious, depressive episodes, Prof Nolen tok say, Van Gogh no paint as much - sometimes not at all for periods - "or wetin e bin produce na very sad paintings, wrey no fit compare to odas".

Vincent van Gogh bin struggle throughout im life, both as artist (e only ever sell one painting) and wit im mental health, but Prof Nolen believe say di tori go probably dey very different if to say di artist dey alive today.

"E fit probably dey diagnosed, e fit see advice say make e no drink and maybe e no go fall into depressive and manic episodes.

"Whether or not e go get effect on say e be painter, e dey very difficult to tok, but e probably for no kill imself."