Autoimmune Diseases: Increasing Incidence or Greater Awareness?

The immune system is a fascinating, complex, and multifaceted network that protects the human body from an extensive range of pathogens. Autoimmune diseases arise when the body's immune response is erroneously unable to differentiate between healthy tissue and potential harmful antigens and attacks itself, targeting an individual's tissues and ultimately leading to organ destruction or dysfunction.^1,2 Examples of autoimmune diseases include rheumatoid arthritis, ulcerative colitis, type 1 diabetes, Graves’ disease, Hashimoto’s thyroiditis, lupus, psoriasis, psoriatic arthritis, vasculitis, Sjögren’s syndrome, and multiple sclerosis.³

There are more than 100 autoimmune diseases. While the incidence may be higher, the Autoimmune Association (AA) notes as many as 24 million Americans are living with some type of an autoimmune disease, and an estimated 5% to 10% of those have more than one autoimmune disease.³ Additionally, autoimmune diseases tend to affect women 3 times more often than men due to hormonal impacts. The AA indicates that an estimated 80% of all patients diagnosed with autoimmune diseases are female.^1,3 Various studies indicate that autoimmune diseases contribute to the leading cause of death among young and middle-aged women.

Genetic factors, environmental influences, and abnormal immunity, including infections, often come together to trigger autoimmune diseases.^1-4 Studies also show that many individuals may be predisposed to autoimmune disorders, which can be triggered by numerous factors including poor diet/lifestyle choices, sedentary lifestyles, extreme stress, grief due to loss of a loved one, and lack of adequate sleep.^1-4,6 Other possible triggers, such as hormonal changes during puberty and pregnancy, put women at greater risk of developing an autoimmune disease.^1-4,6

Recent Clinical Findings

Various studies have suggested ongoing increases in the prevalence of certain autoimmune diseases, but researchers also indicate that it is still unknown if this is due to actual increases or expanded recognition of and/or diagnosis of these diseases.^5-8

Increases in Antinuclear Antibodies

In a study published in Arthritis and Rheumatology,⁵ the researchers found that overall, the prevalence of antinuclear antibodies (ANA), the most common biomarker of autoimmunity, was noticeably rising in the United States, particularly in certain patient populations including male patients, non-Hispanic Caucasians, adults aged 50 years and older, and adolescents. This study was the first to evaluate ANA changes over time in a representative sampling of the US population.

The study included 14,211 participants, aged 12 years and older, in the US National Health and Nutrition Examination Survey (NHANES). The researchers examined the frequencies of ANAs in subjects from three time periods and discovered that ANA prevalence was 11.0% from 1988 to 1991; 11.5% from 1999 to 2004; and 15.9% from 2011 to 2012. Investigators also noted that of the four demographic groups, there were considerable ANA increases in the adolescent group—individuals aged 12 to 19 years demonstrated the largest ANA increases in the study, going from a 2-fold to a 3-fold increase over the three time frames.

The researchers noted that while the exact causes remain unclear, lifestyle changes or environmental factors are key to the increases because the time frame is too short for genetic changes to be a cause.

“Hopefully, this study will stimulate further research on the environmental factors related to the apparent increased prevalence of autoimmune diseases,” the authors stated.

Obesity and Autoimmune Diseases

Health experts indicate that obesity is often overlooked as a risk factor for autoimmune diseases. A study published in Current Obesity Reports⁹ showed that individuals with overweight or obesity often present with more severe forms of some autoimmune disorders, as well as decreased therapeutic responses. They also noted that overweight and obesity may result in deficiencies in the immune system, which in turn may trigger inflammatory responses and boost the risk for the development of some autoimmune diseases.

Autoimmune Disease and Cardiovascular Risk

Researchers aimed to ascertain whether some autoimmune diseases correlated with a heightened risk of cardiovascular disease (CVD). Results published in The Lancet¹⁰ revealed possible connections between 19 of the most common autoimmune disorders and CVD.

The data showed that patients with autoimmune diseases have a substantially higher risk (between 1.4 and 3.6 times depending on which autoimmune condition) of developing CVD than individuals without an autoimmune disorder, and the excess CVD risk is comparable to those with type 2 diabetes.

Diet and Autoimmune Diseases

In a presentation¹¹ at the recent 2022 Rheumatology Nurses Society Conference, researchers indicated that lifestyle modifications such as exercise and anti-inflammatory diet can improve the overall well-being of those with autoimmune diseases.

The presenter provided information on how certain factors such as lifestyle, immune balance, genetics, environmental triggers, and autoimmunity can affect patients with autoimmune diseases. The presenter also noted that all of the aforementioned factors can affect how patients respond to biologic agents used to treat autoimmune diseases. Lastly, integrative measures such as diet, exercise, relaxation, destressing techniques, and obtaining adequate sleep are essential in the treatment of autoimmune diseases, and a balance between conventional and integrative measures may be vital steps to enhancing clinical outcomes.

Perspectives From Clinicians

The following providers shared their experiences with patients who have autoimmune diseases:

“I think that more individuals are aware of autoimmune diseases, and possibly, the majority of the population knows someone who has an autoimmune disease. While drugs for cardiovascular diseases and diabetes are among the most commonly dispensed drugs in our pharmacy, we do dispense a lot of medications that are used to treat and manage autoimmune diseases as well.

Some patients are concerned about adverse effects and some have fears about self-administering the injectable biologics if prescribed for them, but with adequate patient counseling to address their concerns, many patients understand that these drugs will help manage their autoimmune conditions if taken as directed, and the importance of routine medical care from their primary care provider.

In general, patients who are knowledgeable about their disease are more likely to take an active role in their care, thus improving outcomes.”—a pharmacist

Conclusion

Autoimmune diseases can present patients and their loved ones with numerous challenges. The diagnosis and treatment of these diseases can sometimes be complex and arduous and impact patients’ productivity and overall health-related quality of life. The availability and continuing development of targeted therapies have improved clinical outcomes in patients being treated for autoimmune diseases.

While the exact reasons remain largely unclear, research indicates there appears to be both an increase in incidence and recognition/diagnosis of autoimmune diseases. Many health experts say that a balance between conventional and integrative approaches that incorporate lifestyle measures such as exercise, rest, relaxation strategies, and dietary plans tailored to the patient’s needs can enhance outcomes.

Through enhanced understanding about autoimmune diseases and possible risk factors, clinicians can be instrumental in the early identification and implementation of appropriate clinical interventions to improve outcomes.  

References:

1. Xiao ZX, Miller JS, Zheng SG. An updated advance of autoantibodies in autoimmune diseases. Autoimmun Rev. 2021;20(2):102743. doi:10.1016/j.autrev.2020.102743
2. Angum F, Khan T, Kaler J, Siddiqui L, Hussain A. The prevalence of autoimmune disorders in women: a narrative review. Cureus. 2020;12(5):e8094. doi:10.7759/cureus.8094
3. About autoimmunity. Autoimmune Association. Accessed October 4, 2022. https://autoimmune.org/resource-center/about-autoimmunity/
4. Desai MK, Brinton RD. Autoimmune disease in women: endocrine transition and risk across the lifespan. Front Endocrinol (Lausanne). 2019;10:265. doi:10.3389/fendo.2019.00265
5. Dinse GE, Parks CG, Weinberg CR, et al. Increasing prevalence of antinuclear antibodies in the United States. Arthritis Rheumatol. 2020;72(6):1026-1035. doi:10.1002/art.41214
6. Lerner A, Jeremias P, Matthias T. The world incidence and prevalence of autoimmune diseases is increasing. Int J Celiac Dis. 2015;3(4):151-155. doi:10.12691/ijcd-3-4-8
7. Fatoye F, Gebrye T, Svenson LW. Real-world incidence and prevalence of systemic lupus erythematosus in Alberta, Canada. Rheumatol Int. 2018;38(9):1721-1726. doi:10.1007/s00296-018-4091-4
8. Mayer-Davis EJ, Lawrence JM, Dabelea D, et al. Incidence trends of type 1 and type 2 diabetes among youths, 2002-2012. N Engl J Med. 2017;376(15):1419-1429. doi:10.1056/NEJMoa1610187
9. Tsigalou C, Vallianou N, Dalamaga M. Autoantibody production in obesity: is there evidence for a link between obesity and autoimmunity? Curr Obes Rep. 2020;9(3):245-254. doi:10.1007/s13679-020-00397-8
10. Conrad N, Verbeke G, Molenberghs G, et al. Autoimmune diseases and cardiovascular risk: a population-based study on 19 autoimmune diseases and 12 cardiovascular diseases in 22 million individuals in the UK. Lancet. 2022;400(10354):733-743. doi:10.1016/S0140-6736(22)01349-6
11. Munoz GE. Microbiome Dysregulation in Autoimmune Disease (Immunomodulatory Drugs) - Update August 2022. Presented at: Annual Rheumatology Nurses Society Conference; August 3-6, 2022.