Our immune systems is versatile, armed with a variety of weapons that can defend against all sorts of pathogens. But in some people, this powerful arsenal of immune cells and proteins occasionally engages friendly fire by attacking healthy cells, tissues and organs. This self-inflicted assault is referred to as autoimmunity, and it plays a role in more than 100 diseases ranging from type I diabetes to rheumatoid arthritis, according to National Institutes of Health (NIH).
Millions of people are affected by autoimmune diseases – an estimated 5% to 9% of the US population has an autoimmune condition. And although there are many treatments on the market and under development that are designed to deal with the often debilitating symptoms, autoimmune diseases remain incurable.
The prevalence of autoimmune diseases seems to be growing worldwide, though it is unclear why. Lifestyle factors, such as dietary changes, along with advances in diagnostics and a better clinical understanding of these diseases, have likely contributed to the increase in numbers, said Emily Edwards, a researcher in the Department of Immunology and Pathology at Monash University in Australia.
What causes autoimmune diseases?
Autoimmune diseases, like many other conditions, are likely due to the interplay of genetic and environmental factors, but their exact etiology is unclear and varies between disorders.
Yet people with a family history of autoimmune diseases are more likely to develop them – e.g. multiple sclerosis running in families. Some environmental factors such as contaminants, certain drugs, viral infections and diet are also implicated in the manifestation of autoimmune diseases, according to Johns Hopkins Medicine.
Overall, women are twice as likely to suffer from autoimmune diseases as men – and the disorders typically occur during periods of extensive stress, such as pregnancy, a 2020 review paper reported in the journal Cureus. Some autoimmune conditions are more common in certain races and ethnic backgrounds – for example, lupus is most severe in African American and Hispanic people, reports U.S. Department of Health and Human Services (HHS).
Symptoms of autoimmune diseases
Although each disease has specific features, many share characteristic symptoms, such as fatigue, dizziness, and low-grade fever. But the classic sign of an autoimmune disease is inflammation, which can cause redness, heat, pain and swelling, according to NIH.
Too many autoimmune diseases come and go the symptoms or can sometimes be mild and severe in others.
Treatment of autoimmune diseases
There are a multitude of drugs used to treat autoimmune diseases, but what patients are prescribed depends on the disorder, its severity and the symptoms the patient is experiencing.
The medication used can range from mild over-the-counter painkillers to medications designed to replace vital substances that the body can no longer produce, such as insulin for diabetics.
Then there are biological therapies designed to target components of the dysregulated immune response that can suppress the immune system, as well as drugs designed to control the overactive immune system by suppressing its activity.
Using these different types of immunosuppressants is fraught with complications because the immune system is also potentially prevented from mounting a robust response to infections, Edwards said.
Related: Immune Deficiency: Definition and Examples
So doctors need to carefully administer immunosuppressants to try to balance this risk, she said. “They are not the most effective drugs in the world, and what we are trying to do now is find … more targeted therapies that will be more effective.”
In general, the drugs we have are designed to dampen the overactive immune response and the consequences of this overreaction – they do not really address the cause of the immune system’s malfunction, she explained.
“There is a need to identify what the underlying issues are … there is an incomplete understanding at this moment about what they exactly are,” she said. “When we can do that, it allows us to be able to correct them.”
Autoimmune diseases and vaccines
In general, people with autoimmune diseases are advised to get vaccinated, as are healthy people. However, if they are on immunosuppressants that dampen the effects of the immune system, it can lead to a less than optimal response to vaccines, including those against COVID-19, Edwards said.
Although there is little scientific consensus on what level of antibodies and other tools in the armament of the immune system provide protective immunity against the virus that causes COVID-19, some countries have announced plans to administer third vaccine shots to their populations, including people with compromised immune systems.
Related: The United States recommends COVID-19 booster shots 8 months after vaccination
“They may need the extra dose to take them up to a level of a normal individual … to give them the protection they need against the virus,” Edwards said.
Millions of people suffer from autoimmune diseases – estimates suggest that approx 24 mio the United States alone is living with these disorders. In many cases, these are invisible diseases, but patients are in constant danger because immunosuppressants make them far more susceptible to all kinds of infections and reduce their ability to reap the full benefits of vaccines, she added.
“It’s even more of a reason why the general population should be vaccinated,” Edwards said, “to protect these people. [with autoimmune diseases] because it’s hard enough for them, as it is, without having to deal with the worry of catching viruses. “
This article is for informational purposes only and is not intended to provide medical advice.