Toni Braxton has lived with lupus for 15 years. Here's what to know about the disease.

May is Lupus Awareness Month and Toni Braxton is using the opportunity to speak out about living with this chronic autoimmune disease.

In an interview with CBS News Wednesday, the Grammy-winning singer, producer and actress, who is 55 years old, said she was diagnosed with systemic lupus 15 years ago but had symptoms "even years before that."

"I've had some serious health complications, including now it's starting to affect my kidneys. ... My skin, my hair, my heart, my vital organs are starting to become affected," she said. "I love performing. I love touring, but I know I can't do six to seven shows a week. My body's not gonna let me do that. But I always try to find the silver lining. Maybe I can do two to three shows a week."

Braxton is teaming up with Aurinia Pharmaceuticals for its "Get Uncomfortable" campaign, and encouraging others with lupus to keep up on their health checks. 

"Don't miss your doctor's appointments. They're so important," she said. "Just because you have lupus doesn't mean it has you... We can live with it. Go to the doctor, get checked out."

Here are some basics to know about lupus:

What is lupus?

Lupus is a chronic disease that can cause inflammation and pain throughout the body. It is an autoimmune disease, meaning the body's immune system — which usually fights infections — attacks its own healthy tissues and organs, the Mayo Clinic explains. 

When people talk about lupus, they're usually referring to systemic lupus, which is the most common form, according to the Lupus Foundation of America. But there are also three other kinds, the organization explains, including:

• Cutaneous lupus: a form of lupus that is limited to the skin
• Drug-induced lupus: a lupus-like disease caused by certain prescription drugs
• Neonatal lupus: a rare condition that affects infants of women who have lupus

Who is affected by lupus?

While anyone can develop lupus, women are at higher risk, getting the disease nine times more often than men, according to the National Institutes of Health.

"Most often it happens in people between ages 15 and 45 years, but lupus can occur in childhood or later in life as well," the NIH notes on its website.

That's why Braxton's efforts are focused on empowering women and encouraging them to stick to their doctor's appointments.

"Ladies, we've got to take that time to take care of ourselves," she said in the interview.

Lupus is also more common in African Americans and people of American Indian and Asian descent, as well as those with a family history of lupus or another autoimmune disease.

What are symptoms of lupus?

Inflammation caused by lupus can affect many different body parts of the body, including joints, skin, kidneys, blood cells, the brain, heart and lungs — but no two cases of lupus are exactly alike, the Mayo Clinic explains. 

"Signs and symptoms may come on suddenly or develop slowly, may be mild or severe, and may be temporary or permanent," the organization's website says. "Most people with lupus have mild disease characterized by episodes — called flares — when signs and symptoms get worse for a while, then improve or even disappear completely for a time."

Common symptoms include extreme fatigue, joint pain or a butterfly-shaped rash that appears across the face, according to the Lupus Foundation.

Depending on what part of the body is affected by the disease, the Mayo Clinic says other symptoms can include: 

• fever
• joint stiffness and swelling
• skin lesions that appear or worsen with sun exposure
• shortness of breath
• chest pain
• dry eyes
• headaches and more

What causes lupus?

Medical experts don't yet know what causes lupus in most cases, but it's likely a combination of genetics and environmental factors, the Mayo Clinic says.

"It appears that people with an inherited predisposition for lupus may develop the disease when they come into contact with something in the environment that can trigger lupus," the organization says, listing sunlight, infections and certain medications as potential triggers for some people. 

Lupus is also not contagious, the Lupus Foundation adds, so you can't "catch" it or give it to someone else.

Are there lupus treatments?

While there is not yet a cure for lupus, there are options to help prevent flares, treat symptoms when they happen, and reduce organ damage, according to the Centers for Disease Control and Prevention. 

"Several different types of medicines treat lupus. Your doctors and nurses may change the medicine they prescribe for your lupus as your symptoms and needs change," the organization's website reads.