Gossip Girl and Buffy the Vampire Slayer actress Michelle Trachtenberg, 39, was found dead Wednesday, February 26, in her New York City apartment.

Trachtenberg’s cause of death has not been revealed, but police have said it is not being treated as suspicious. However, there has been speculation it may be related to liver transplant surgery that she recently underwent, according to sources.

One in 100 Americans are diagnosed with liver disease, and the condition kills nearly 50,000 every year according to the CDC. According to the British Liver Trust, in the UK there are more than 11,000 deaths due to liver disease each year.

The British Liver Trust also said that 9 in 10 cases could be prevented, with alcohol, viral hepatitis, and obesity being the major causes. Additionally, many people are diagnosed at the late stages, meaning their condition cannot be cured.

So catching the disease early is the best way to increase the chances of successful treatment. But what are the signs of liver disease?

There are different types of liver disease, the most common being: Alcohol-related liver disease, Non-alcoholic fatty liver disease, Hepatitis, Haemochromatosis, and Primary biliary cholangitis. Most of these are caused either by drinking too much alcohol or being overweight or obese. But they can also be caused by a weak immune system, catching a viral infection, or in the case of Haemochromatosis, a result of genes.

In the early stages of liver disease, there are rarely symptoms. The NHS explains: “Once you start to get symptoms of liver disease, your liver is already damaged and scarred. This is known as cirrhosis.”

Symptoms of cirrhosis include:

  • feeling very tired and weak all the time
  • loss of appetite
  • loss of sex drive (libido)
  • yellow skin and whites of the eyes (jaundice)
  • itchy skin
  • feeling or being sick

If you experience any of these symptoms the NHS recommends seeing a GP right away.

The best way to prevent liver disease is to maintain a healthy lifestyle and not drinking over the recommended alcohol intake. Vaccines are also available for hepatitis B and hepatitis A.

Trachtenberg’s family said in a statement: “It is with great sadness to confirm that Michelle Trachtenberg has passed away. The family requests privacy for their loss.”

Authorities said the actress’ death was not being treated as suspicious.

“Criminality is not suspected. The medical examiner will determine the cause of death. The investigation remains ongoing,” the NYPD said in a statement.