Did Van Gogh’s brother Theo have syphilis?

For many years it was regarded as distasteful to suggest that Theo van Gogh, the painter’s brother, died of syphilis. Theo’s son, named Vincent after his artistic uncle, lived until 1978. Understandably, he disliked any mention of the topic.

Since the death of Theo’s son, his descendants have become more relaxed about the medical diagnosis. The Van Gogh Museum’s annotated version of the artist’s letters now records that by September 1890 Theo was in “the advanced stages of syphilis”.

But when did Theo first realise that he had caught the dreaded disease? And did he tell his brother Vincent? Answers to these questions might throw fresh light on the artist’s suicide.

In May 1888, a few months after Vincent’s arrival in Arles, Theo wrote about a medical consultation he had had in Paris with Dr David Gruby. Vincent responded that he was “upset” by the resulting news.

Vincent went on to allude to the fact that his brother was taking potassium iodide. This medication was widely used in cases of cerebral syphilis, although it was also prescribed for other conditions. Vincent added that he was expecting Dr Gruby would have advised his brother “not to see women”. Vincent also referred to Theo’s “heart” condition, and one wonders whether this might possibly have been a euphemism for a disease that Theo had caught from a sexual companion.

It seems likely that Theo, who also had other medical problems (including a chronic cough), was diagnosed by Dr Gruby as having developed syphilis.

Eight months later Vincent painted a still life which prominently depicted a copy of the Manuel Annuaire de la Santé, a popular health manual by F.V. Raspail. Although Vincent was presumably primarily concerned with his own health (both physical and mental), having just mutilated his ear, this book does include a five-page section on “secret diseases, venereal, syphilitic”.

To briefly explain the family circumstances, in April 1889 Theo had married Jo Bonger. A month later Vincent moved to a mental asylum just outside Saint-Rémy-de-Provence. The infant Vincent, the son of Theo and Jo, was born in January 1890. In May 1890 Vincent left the asylum to stay in the village of Auvers-sur-Oise, north of Paris. And, tragically, on 27 July 1890 Vincent shot himself in the chest, dying two days later.

Theo, who was heartbroken by Vincent’s death, then fell seriously ill at the beginning of October 1890, just over two months after his brother’s suicide. Theo endured terrible suffering and was often violent in his last few weeks. He died on 25 January 1891, aged just 33.

Medical records opened up to researchers in 1992 confirm that Theo had suffered from dementia paralytica, a symptom of late-stage syphilis. The neurologist Piet Voskuil, who has studied Theo’s condition, believes that he could have caught the disease as far back in 1886.

A key question which has rarely been explored in the Van Gogh literature is whether Theo’s medical prognosis was a factor behind Vincent’s suicide.

Vincent may well have learned about concerns over syphilis while he was living with Theo in Paris from February 1886 to February 1888. An initial diagnosis from this period appears to have been confirmed by Dr Gruby in May 1888, after Vincent’s move to Arles. Vincent must have learned more in the spring of 1890, when the two brothers met again. It was hardly an easy subject to broach by letter.

Vincent met Theo on three occasions in 1890: he stayed with him in Paris for four days in mid May on his way from Saint-Rémy to Auvers; Theo, along with his wife and infant son, visited him for the day in Auvers on 8 June; and Vincent went on a day trip to Paris on 6 July. The two brothers were very close and it is highly likely that they would have discussed medical issues when they met.

By the spring of 1890 Theo’s condition had worsened. Syphilis was then incurable, leading to death in the most unpleasant of circumstances. Only from the 1930s would penicillin provide a cure.

Vincent had presumably learned by the spring of 1890 that Theo’s syphilis had been confirmed and his health was deteriorating, so he would have been extremely distressed. Theo’s approaching death would have no doubt represented a great personal loss for Vincent.

It would also mean the loss of the financial allowance that he had received from Theo for many years. This money had given him the means to pursue a career as an artist, since he had failed dismally to sell his work. Art meant everything to Vincent, but without this financial support he would be unable to continue.

On the day of his arrival in Auvers in May 1890, after his four days with Theo in Paris, Vincent had a consultation with Dr Paul Gachet, a medical practitioner, amateur artist and collector. The doctor’s son later wrote that his father recorded that Vincent suffered from “syphilomanie non fondée” (unfounded phobia of syphilis).

There is no evidence that Vincent had syphilis, but he presumably bombarded the doctor with questions about it—not for himself, but because of concerns about his brother.

Suicidal behaviour is complex and can rarely be attributed to a single cause. Theo and his wife Jo were facing a series of practical problems which worried Vincent: Jo and the baby had other medical issues, Theo had a row with his employers at the gallery where he worked, and the married couple were undecided on whether they should suffer the disruption of moving to another apartment. July 1890 was a stressful time for the whole family.

More significantly, Vincent had long suffered from a sense of rejection by society, often giving him an intense feeling of loneliness. Despite his deep commitment to art, he was unable to sell his paintings. This led him to regret that Theo was having to support him, particularly after his brother had married and had a young child to look after. And after mutilating his ear in Arles, Vincent was always worried that a similar incident could recur.

However, a fear that Theo might only have a few more months to live would have caused Vincent even greater despair. Syphilis was what Raspail, in his book, called a “secret disease”. It was not something that could be easily discussed, so not surprisingly there is never any direct mention in the surviving correspondence of either Vincent or Theo.

It is virtually certain that Theo had syphilis—and it is highly likely that Vincent had learned of this by spring 1890. This was probably one of the reasons why he decided to end his life, shooting himself on 27 July while in the wheatfields. 

Devastated by the news, Vincent’s sudden death must have weakened any resolve that Theo might have had to try to cling onto life. The two brothers now rest side by side in the cemetery at Auvers, their graves linked by a covering of ivy.