Princess Mette-Marit of Norway diagnosed with lung disease

She has had health issues for a number of years

The Royal Court of Norway has announced that Princess Mette-Marit has been diagnosed with chronic pulmonary fibrosis. The statement from the Royal Court, which was released on Wednesday, read: "The Crown Princess has undergone extensive investigations related to her health and an unusual variant of fibrosis has been detected in the lungs, according to the Crown Princess’s doctor, Professor Kristian Bjøro at the National Hospital. It is not yet clear whether the pulmonary disease is linked to a more extensive autoimmune disease process or if there are other causes that underlie the lung changes."

Prince Haakon and Princess Mette-Marit out in September

The 45-year-old Crown Princess has also released an accompanying statement, saying: "For a number of years, I have had health challenges on a regular basis, and now we know more about what these are in. The condition means that the working capacity will vary. The Crown Prince and I choose to inform about this now, partly because in future there will be a need to plan periods without the official program. In connection with treatment and when the disease is more active, this will be necessary." She added: "Although such a diagnosis in times will limit my life, I’m glad that the disease has been discovered so early. My goal is still to work and participate in the official programme as much as possible."

READ: Princess Mette-Marit of Norway pictured for the first time since undergoing surgery

According to the British Lung Foundation, pulmonary fibrosis is a term that covers many different conditions that cause scar tissue to build up in your lungs.The Princess had to cancel her official engagements in Spring to undergo minor surgery, although it wasn't confirmed what the surgery was for.

WATCH: Crown Princess Mette-Marit in NYC earlier this year

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