Co-morbidities in established rheumatoid arthritis.

Co-morbid conditions are common in patients with rheumatoid arthritis (RA). Although the presence of co-morbid conditions can be assessed using standardised indexes such as the Charlson index, most clinicians prefer to simply record their presence. Some co-morbidities are causally associated with RA and many others are related to its treatment. Irrespective of their underlying pathogenesis, co-morbidities increase disability and shorten life expectancy, thereby increasing both the impact and mortality of RA. Cardiac co-morbidities are the most crucial, because of their frequency and their negative impacts on health. Treatment of cardiac risk factors and reducing RA inflammation are both critical in reducing cardiac co-morbidities. Gastrointestinal and chest co-morbidities are both also common. They are often associated with drug treatment, including non-steroidal anti-inflammatory drug and disease-modifying drugs. Osteoporosis and its associated fracture risk are equally important and are often linked to long-term glucocorticoid treatment. The range of co-morbidities associated with RA is increasing with the recognition of new problems such as periodontal disease. Optimal medical care for RA should include an assessment of associated co-morbidities and their appropriate management. This includes risk factor modification where possible. This approach is essential to improve quality of life and reduce RA mortality. An area of genuine concern is the impact of treatment on co-morbidities. A substantial proportion is iatrogenic. As immunosuppression with conventional disease-modifying drugs and biologics has many associated risks, ranging from liver disease to chest and other infections, it is essential to balance the risks of co-morbidities against the anticipated benefits of treatment.