Risk Factors of Autoimmune Diseases

Genetic Risk Factors

Genetics plays a significant role in the development of autoimmune diseases. Family history and specific genetic markers can increase an individual's susceptibility to these conditions.

Family History

If a close family member, such as a parent or sibling, has an autoimmune disease, the risk of developing an autoimmune condition is higher. For example, if a parent has rheumatoid arthritis (RA), their children are at an increased risk of developing RA or even another autoimmune disease.

Specific Genes

Certain genes like the Human Leukocyte Antigen (HLA) complex are associated with a higher risk of autoimmune diseases. The HLA plays an important role in immune system regulation. Variations in HLA genes can affect how the immune system distinguishes between self and non-self, leading to autoimmune responses. For example, the HLA-DRB1 gene is associated with an increased risk of RA and type 1 diabetes.

Environmental Risk Factors

Environmental factors can trigger or aggravate autoimmune diseases, particularly in individuals with a genetic predisposition.

Infections

Infections caused by bacteria, viruses, or other pathogens can trigger autoimmune responses. Research suggests pathogens that have components resembling human tissues can cause the immune system to mistakenly attack both the pathogen and the body's own cells. For example, the Epstein-Barr virus has been linked to systemic lupus erythematosus (SLE) multiple sclerosis (MS).

Exposure to Toxins and Chemicals

Occupational exposure to silica dust, for example, is associated with an increased risk of developing systemic sclerosis (scleroderma) and RA. Smoking (including passive smoking) has been identified as a risk factor for RA, SLE, and other autoimmune conditions.

Hormonal Risk Factors

Hormones play a critical role in the immune system. And so, hormonal changes can impact the development and progression of autoimmune diseases.

Gender

Autoimmune diseases are more common in women than men, suggesting that sex hormones, such as estrogen and progesterone, may influence immune system function. Women are significantly at greater risk of developing SLE, RA, and other autoimmune diseases.

Pregnancy

The hormonal changes during pregnancy can impact autoimmune disease activity. Some autoimmune diseases, such as RA, can improve during pregnancy but also flare up postpartum. Other conditions, such as SLE, may worsen during pregnancy.

Lifestyle Risk Factors

How we live our lives definitely lower or increase our risk of developing autoimmune diseases.

Smoking

A well-documented risk factor, smoking is associated with an increased risk of RA, MS, and SLE. It can trigger autoimmune responses, exacerbate inflammation, and even worsen disease progression.

Stress

Chronic stress can affect the immune system by altering the balance of pro-inflammatory and anti-inflammatory cytokines. This imbalance has been known to trigger or worsen autoimmune responses.

Read about the connection between stress and multiple sclerosis here.

Diet and Nutrition

A diet high in processed foods, sugar, and unhealthy fats can contribute to chronic inflammation and increase the risk of autoimmune diseases. On the other hand, a diet rich in anti-inflammatory foods, such as fruits, vegetables, whole grains, and omega-3 fatty acids, greatly lowers this risk.

Probiotics are beneficial bacteria that help restore gut balance, while prebiotics are dietary fibers that feed these bacteria. Consuming foods rich in probiotics (yogurt, kefir, soybean, cabbage, apple cider vinegar, lassi, fermented cheese) and prebiotics (garlic, onions, bananas) can support gut health, thereby potentially reducing the risk of autoimmune diseases.

You can read more about the autoimmune diet here.

The Role of the Gut Microbiome

The gut microbiome consists of trillions of microorganisms that play a critical role in immune system regulation. Dysbiosis, or an imbalance in the gut microbiome, has been linked to various autoimmune diseases.

Leaky Gut

An imbalance in gut bacteria can lead to increased intestinal permeability, also known as "leaky gut." Due to this, toxins and undigested food particles enter the bloodstream, typically triggering an immune response and possibly leading to the development of autoimmune diseases.

Risk Factors for Common Autoimmune Diseases

Let’s take a look at the risk factors associated with the 5 most common autoimmune conditions.

Rheumatoid Arthritis (RA)

Smoking

Genetics: Variations in HLA-DRB1 and other genes

Gender and Hormonal Factors: Women are more likely to develop RA; and hormonal changes, such as menopause, can affect disease activity

Infections: Certain infections may trigger RA in genetically predisposed individuals

Systemic Lupus Erythematosus (SLE)

Genetics: Family history and specific genetic markers, such as HLA-DR2 and HLA-DR3

Gender: Women, especially those of childbearing age

Environmental Factors: UV light exposure

Infections: EBV infection

Multiple Sclerosis (MS)

Genetics: Variations in HLA-DRB1 and other genes

Geography: Higher prevalence in regions farther from the equator (linked to possible vitamin D deficiency)

Infections: EBV and other viral infections

Smoking

Type 1 Diabetes

Genetics: Specific genes, such as HLA-DR3 and HLA-DR4

Infections: Viral infections, such as Coxsackievirus

Diet: Early introduction of cow's milk and gluten in infancy

Animal milk should be introduced only after 1 year of age.

Inflammatory Bowel Disease (IBD)

Genetics: Family history and specific genetic markers, such as NOD2/CARD15

Smoking

Diet: A diet high in processed foods and low in fiber

Stress

Read more about the types of autoimmune diseases here.