An autoimmune disease occurs when the body’s natural defense system becomes misguided and attacks its own healthy tissues. The link between environmental factors and these conditions is an area of growing scientific interest. Among these factors, tobacco smoking is recognized as a contributor to the development and severity of many autoimmune disorders. This article explores how smoking influences the immune system and how quitting can affect the course of an autoimmune disease.
The Immune System Under the Influence of Smoking
Tobacco smoke contains thousands of chemicals that disrupt the immune system, creating an environment that fosters autoimmunity. It achieves this by promoting a state of chronic, low-grade inflammation throughout the body. This persistent inflammatory state can cause the immune system to remain on high alert, mistaking the body’s own cells for foreign invaders.
This state of alert is intensified by oxidative stress, a condition where harmful molecules called free radicals overwhelm the body’s antioxidant defenses. Cigarette smoke is a major source of these free radicals, which damage cells and their DNA. This cellular damage can alter proteins in the body, causing them to be seen as foreign by the immune system and triggering an autoimmune reaction.
In response to these altered proteins, the immune system may produce autoantibodies, which mistakenly target the body’s own tissues. Smoking stimulates the production of specific autoantibodies associated with several autoimmune diseases. For example, it can trigger the creation of antibodies that recognize citrullinated proteins, which are strongly linked to rheumatoid arthritis.
Smoking’s Role in Specific Autoimmune Conditions
The immune disruptions caused by smoking have specific consequences for various autoimmune diseases. For rheumatoid arthritis (RA), smoking is one of the most established environmental risk factors. It is strongly associated with the development of the more severe, autoantibody-positive form of the disease. Smokers have a higher risk of developing RA, and continued smoking is linked to more aggressive joint damage and reduced effectiveness of treatments like methotrexate and anti-TNF therapies.
In multiple sclerosis (MS), a disease affecting the central nervous system, smoking is known to accelerate disease progression. Studies show that smokers with relapsing-remitting MS are more likely to transition to the more debilitating secondary progressive phase. Each year of smoking after an MS diagnosis speeds up the time to this conversion. Quitting, however, can slow this progression, with former smokers showing a conversion rate similar to that of never-smokers.
For individuals with systemic lupus erythematosus (SLE), smoking is associated with higher disease activity, particularly affecting the skin and kidneys. Current smokers with lupus tend to have higher scores on disease activity indexes compared to non-smokers and ex-smokers. Furthermore, smoking can interfere with the effectiveness of lupus medications like hydroxychloroquine, making it more difficult to control symptoms.
The impact of smoking is also profound in Crohn’s disease, a type of inflammatory bowel disease (IBD). Smokers have approximately double the risk of developing Crohn’s compared to non-smokers. For those already diagnosed, smoking is linked to more frequent flare-ups, a greater need for potent medications, and a higher likelihood of requiring surgery. After surgery, smokers have a much higher rate of disease recurrence.
The relationship between smoking and IBD is complex, as smoking appears to have a different effect in ulcerative colitis (UC), the other major form of IBD. Some studies suggest smoking may offer a degree of protection against developing UC and can lead to a milder disease course. However, this single observation is vastly outweighed by the severe health risks associated with smoking, and healthcare professionals advise against it for everyone.
The Health Advantages of Quitting for Autoimmune Patients
Ceasing to smoke offers substantial health benefits for individuals with an autoimmune disease, often leading to reduced disease activity. For many patients, quitting can lead to fewer and less severe flare-ups. This is because the body is no longer exposed to the constant inflammatory triggers in tobacco smoke, allowing the immune system to become less reactive.
Quitting smoking can also enhance the effectiveness of treatments. Medications for conditions like rheumatoid arthritis and lupus often work better in non-smokers because smoking can interfere with how these drugs are metabolized. Removing tobacco allows these therapies to function as intended, which can lead to better long-term outcomes and may allow for a reduction in medication dosage under a doctor’s supervision.
For progressive diseases such as multiple sclerosis, smoking cessation can slow the advancement of disability. The accelerated transition from relapsing-remitting MS to secondary progressive MS seen in smokers can be mitigated by quitting. While not a cure, cessation is a tool for managing the disease’s trajectory and preserving function for longer.
Finally, quitting smoking provides broad improvements to general health. The cardiovascular and respiratory systems, which are often under strain in autoimmune conditions, are given a chance to recover. Lowered blood pressure and improved lung function reduce the risk of heart disease and other complications, supporting the body’s ability to manage the autoimmune condition more effectively.
Navigating the Quitting Process with an Autoimmune Condition
Successfully quitting smoking requires a plan, especially for individuals with an autoimmune disease. The first step is to collaborate with your healthcare team. Before setting a quit date, discuss your intentions with your rheumatologist or specialist. They can provide tailored advice and help integrate your smoking cessation plan with your ongoing disease management.
The stress associated with nicotine withdrawal can be a concern, as stress is a known trigger for disease flares in many autoimmune conditions. Developing strategies to manage this is part of the quitting process. Techniques such as mindfulness, deep breathing exercises, or light physical activity—approved by your doctor—can be effective in mitigating withdrawal-related stress.
Discussing quit methods with your doctor is the best way to make an informed decision. Your doctor can help you select the best approach by considering potential interactions with your current autoimmune medications and your overall health profile. Common options include:
- Nicotine replacement therapy (NRT) in the form of patches or gum
- The prescription medication varenicline
- The prescription medication bupropion