The Connection between Rheumatoid Arthritis and Sleep Apnoea

Rheumatoid arthritis is a chronic debilitating disease which is also known as an auto-immune disease. This medical condition usually causes inflammation and swelling around the joints, further causing pain and affecting all other organs in the body. Joints affected with rheumatoid arthritis usually become stiff and painful when moved, adding fatigue and discomfort to the sufferer.

It is also a known fact that people with rheumatoid arthritis are at an increased risk of developing cardiovascular disease or heart attacks as compared to other people who do not have this disease. This cardiovascular problem in patients with rheumatoid arthritis is also linked to obstructive sleep apnoea. As defined, obstructive sleep apnoea

Patients with rheumatoid arthritis have a significantly higher risk of having a heart attack, compared to other people. Obstructive sleep apnoea is a medical condition which is defined as periods of cessation of breathing and reduction of ventilation during sleep. Sleep apnoea is also associated with a lot of illnesses such as diabetes, obesity, abnormal blood cholesterol levels, hypertension, stroke, heart disease and other illnesses.

However, the question is, is there a relationship between obstructive sleep apnoea and rheumatoid arthritis. Can patients with long-term rheumatoid arthritis be also at risk for obstructive sleep apnoea? There were previous studies which have found out that obstructive sleep apnoea can contribute to cardiovascular disease in patients with rheumatoid arthritis. There are little studies establishing whether obstructive sleep apnoea can exist in rheumatoid arthritis patients.

A study by Reading et al in the 2009 Journal of Rheumatology tried to examine the risk for sleep apnoea in patients with RA compared to subjects without RA. This study recruited RA patients and non-RA subjects who were age and sex matched from the same population. These persons completed the Berlin Sleep Questionnaire, which evaluated their level of risk (high or low) for sleep apnoea. In addition, there were three subscales evaluating snoring, fatigue, and relevant co morbidities (i.e. high blood pressure and obesity (body mass index (BMI) ≥ 30 kg/m2)). Chi-square tests were used for comparisons.

The study found out that there was no difference in snoring (p = 0.31) or in the co morbidities subscale (p = 0.37). However, RA patients reported more fatigue (38%) than subjects without RA (13%; p < 0.001). Overall, the risk for sleep apnoea was significantly higher for the RA patients (50%) than the non-RA subjects (31%; p < 0.001).

The study also found out that subjects at high risk for sleep apnoea are also more likely to be male, have high blood pressure, and have a higher average BMI with more individuals in the BMI classification of obese, than those in the low risk of sleep apnoea category. The small percentage of patients who were diagnosed to have obstructive sleep apnoea is said to be small, suggesting that sleep apnoea may be under diagnosed in these patients.

The results of this study only showed that obstructive sleep apnoea can potentially contribute to the development of cardiovascular disease in patients with rheumatoid arthritis. This may be related to the inflammatory, coagulation, and endothelial changes associated with obstructive sleep apnoea, which are also present in patients with rheumatoid arthritis. The autonomic nervous system disturbance associated with obstructive sleep apnoea may be responsible for this. This makes people who have obstructive sleep apnoea at risk for sudden cardiac deaths especially at night.

Considering that patients with rheumatoid arthritis are at high risk for sleep apnoea, these patients should be tested for the disorder and those found out to have sleep apnoea should be treated immediately to avoid the increased risk for cardiovascular illnesses and deaths.

Reference:

Reading SR, Crowson CS, Rodeheffer RJ, Fitz-Gibbon PD, Maradit-Kremers H, Gabriel SE. Do rheumatoid arthritis patients have a higher risk for sleep apnoea? J Rheumatol. 2009 Sep;36(9):1869-72.

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