If you have psoriasis, you are already at increased risk to develop other conditions like arthritis, eye problems, and heart disease. But there’s another illness that you should know about, too: liver disease. You’re not only at greater risk to develop liver disease, you’re at greater risk for it to develop into cirrhosis, or liver scarring.
What’s the Connection Between Psoriasis and Liver Disease?
It may seem like there should be little connection between the two. Psoriasis is a skin disease that causes red, itchy, scaly patches. Nonalcoholic fatty liver disease (NAFLD) is a condition where too much fat is stored in liver cells. Over time, this can lead to cirrhosis and liver failure.
But while NAFLD is found in about 30% of the population, some evidence suggests it’s present in up to half of all people who have psoriasis. There may be a couple of reasons why:
- People who have psoriasis are more likely to have other conditions, such as obesity, type 2 diabetes, high blood pressure, or elevated cholesterol, that also raises risk of developing NAFLD.
- Both conditions are inflammatory conditions. It’s thought that the same chemical compounds, cytokines, that cause the skin inflammation in psoriasis also raise blood sugar and cholesterol levels. This in turn makes it more likely that you’ll develop NAFLD.
- Certain medications used to treat psoriasis, like methotrexate, can cause liver problems.
In general, the more psoriasis you have on your body, the greater your risk to not only have liver disease, but severe liver disease. This lines up with other research that has found that people who had psoriasis on at least 10 percent of their body had nearly double the risk of death.
But just as psoriasis raises the risk of liver disease, the relationship goes the other way, too. Studies have found that having certain other forms of liver disease raises your risk of psoriasis, too. This includes:
- Alcoholic liver disease
- Primary biliary cholangitis, an autoimmune disease where your body destroys the bile ducts in your liver
- Autoimmune hepatitis, a rare disease where your body attacks your liver cells
- Hepatitis C
It’s not known if the combination of psoriasis and liver disease is more or less common among people of color. While psoriasis is found more frequently in white people than Black or Hispanic people, it may simply be that it gets diagnosed less in those populations. Psoriasis can often be misdiagnosed or go undiagnosed in people with darker skin tones. Chronic liver disease – and deaths from liver disease – are higher among African American people.
How Do I Get a Double Diagnosis?
It can be hard to know if you have liver disease because it often doesn’t have any symptoms except in the late stages. That’s why if you have psoriasis, it’s a good idea for your dermatologist or primary care doctor to do blood tests to check your liver’s health, especially if you’re taking medication to control your psoriasis. This includes:
- Serum bilirubin test. This measures the level of bilirubin in your blood. Your liver removes bilirubin from your body. If your level is high, it means your liver may have trouble doing this.
- Serum albumin test. This checks the level of a protein called albumin. Low levels may mean your liver is having trouble working. Albumin is made by the liver and prevents fluids from leaking out of the bloodstream.
- Alanine transaminase (ALT) test. This test measures the level of alanine transaminase, a liver enzyme that is released into the bloodstream after liver cell damage.
- Aspartate transaminase (AST) test. This test measures the level of the liver enzyme aspartate transaminase, which is also released into the bloodstream after liver cell damage. This enzyme is also found in muscle and organs.
- Gamma-glutamyl transpeptidase (GGT) test. This test measures the level of the liver enzyme gamma-glutamyl transpeptidase to check the health of the liver.
If any of these tests are abnormal, your doctor may order more blood tests, or imaging like an ultrasound of your liver, to look for other signs of NAFLD.
How Can I Treat Both?
The good news is some of the lifestyle treatments that help psoriasis may also help get your NAFLD under control. These include:
Maintain a healthy weight. If you are overweight, a weight loss of just 10% (that’s 15 pounds for a 150-pound woman) can decrease liver fat. It can also help lower your need for psoriasis medications and improve how well your treatment works. Some people discover that a psoriasis drug that didn’t help them before does once they lose weight.
Eat a healthy diet. Studies have shown that diets high in saturated fats and high-fructose corn syrup (found in many processed and packaged foods) can lead to NAFLD. Research also shows that these foods can also aggravate psoriasis. An anti-inflammatory diet like the Mediterranean diet (a diet rich in fruits, veggies, whole grains, beans, seeds, fatty fish, and olive oil) may have the best effects.
Stay active. Exercise decreases liver fat and reduces some of the inflammation associated with NAFLD. It’s also been shown to improve psoriasis severity in psoriasis patients who are also overweight or obese.
Avoid alcohol. It can trigger psoriasis flares and worsen NAFLD.
Check with your doctor about medications. Some drugs used to treat psoriasis, like methotrexate or a class of drugs known as biologics, can cause liver damage. If you do take one of them, it’s very important that your doctor check your liver function regularly. Research shows that people with psoriasis who take these medications have the highest risk to develop NAFLD and cirrhosis.