There were rumors toward the end of 2013 that pop singer Selena Gomez cancelled her Australian tour to treat lupus flares. Lupus is an autoimmune disease that typically affects the skin, joint, blood, and kidneys — a disease for which there's no cure. Now, Gomez has revealed to Billboard that yes, she's been diagnosed with lupus and really took that break to undergo chemotherapy.

"I could’ve had a stroke," Gomez told the magazine. "I wanted so badly to say, 'You guys have no idea. I’m in chemotherapy. You’re a--holes.' I locked myself away until I was confident and comfortable again."

According to NBC News contributor Dr. Natalie Azar, Gomez is right: Heart disease is the leading cause of death among people with lupus. The disease also tends to affect more young women than men, with symptoms first appearing during a woman's child-bearing years, Azar said; her 20s, 30s, and 40s.

Lupus may only affect 8 percent of the popluation, but the Centers for Disease Control and Prevention reported that 78 percent of those cases are women and, more often than not, runs in the family. Put it another way: Vox cited that lupus affects 1.5 million Americans, and 90 percent of those diagnosed with lupus are women. A 2014 study found, too, that lupus hospital readmissions were higher among female minorities on public health insurance. Yet, scientists haven’t figured out what exactly causes the rare disease in the first place. They suspect a host of reasons that range from hormones to different environmental factors.

"What is known is that some of us seem to inherit a susceptibility to these diseases and then an environmental factor triggers them," Azar said. "So, while you may not have a family history of lupus or rheumatoid arthritis, for example, that doesn't mean you haven't inherited the genes that put you at risk for developing them. While the genetics are necessary they are not sufficient to cause the disease."

Is chemo the only option?

The short answer is no; the right lupus treatment is dependent upon several factors. For one, the Lupus Foundation of America (LFA) reported that there are four types of lupus: Systemic lupus is the most common, accounting for 70 percent of all cases, followed by cutaneous lupus (affecting only the skin), drug-induced lupus (brought on by meds), and the even rarer neonatal lupus. The type of lupus a patient has will steer them toward necessary and effective treatment.

What’s more is that lupus can cause damage to certain organs, like the skin, heart, kidney, brain and nervous system, as well as the gastrointestinal tract. So once patients are diagnosed (typically by a rheumatologist), both the patient and doctor will work out a treatment plan based on the patient’s age, symptoms, general health, and lifestyle, the LFA said.

Treatment aims to reduce inflammation, suppress an overactive immune system, and control symptoms like joint pain to prevent flares, respectively. Everyday Health reported that these flares can be classified as mild, moderate, or severe, and they stem from anything that triggers the immune system, including but not limited to stress. It's common for patients to go through "quiet periods" before the disease flares up.

The LFA said people with lupus often have to manage disease-related conditions to manage the pain. For example, some patients need diuretic for fluid retention, antihypertensive drugs for high blood pressure, and antibiotics for infections. And in certain cases, like Gomez’s, lupus can be treated with a class of chemotherapy drugs called cyclophosphamide. The Cleveland Clinic reported that this particular drug is used for its "very powerful effects on reducing the activity of the immune system."

That said, an LFA survey revealed that 78 percent of lupus patients are coping well with the disease. Survey respondents also said that pain, lifestyle changes, and emotional problems associated with lupus are some of the harder obstacles associated with the disease, but with the right plan and health care team, it’s not impossible. Just look at Gomez: Last week she released her second solo studio album, Revival, and has already listed dates for her world tour in 2016.

“ This is my time,” she said. “I’ve deserved this. I earned it. This is all me."