What is Elderly-onset Rheumatoid Arthritis and How Should it be Treated?

Elderly onset rheumatoid arthritis (EORA) is a misnomer since it refers to rheumatoid arthritis affecting people 60 years of age or older. Since this author recently reached the age of 60 and certainly doesn't consider himself elderly, the definition should be changed.

Rheumatoid arthritis (RA) affects 2% of those 60 years old and older and is generally more common among women. When RA presents in patients past the age of 60, it may present with an acute onset, with significant inflammatory symptoms, and predominant upper extremity involvement, eg. shoulders. Inflammatory markers in the blood such as the erythrocyte sedimentation rate (ESR) may be greatly elevated.

Diagnostic testing is similar to that for diagnosing RA in younger individuals. Acute phase reactants for inflammation such as the ESR and CRP will invariably be abnormal. Serologic testing for rheumatoid factor and anti-cyclic citrullinated protein (anti-CCP) are helpful.

The diagnostic imaging procedure of choice is probably magnetic resonance imaging (MRI), although diagnostic ultrasound may be useful.

Other disease processes that need to be excluded include: calcium pyrophosphate deposition disease (CPPD), osteoarthritis, gout, polymyalgia rheumatica (PMR), arthritis associated with infections such as hepatitis B,C , and immunodeficiency virus. Tuberculosis and fungal infections such as histoplasmosis, coccidiomycosis, and blastomycosis can also present with inflammation of many joints.

Endocrine disorders such as diabetes and Cushing's disease may also present with diagnostic challenges.

Malignancy is another consideration. An inflammatory arthritis affecting many joints in a patient over the age of 60 should lead the physician to working up the patient for an underlying malignancy. Also, certain malignancies such as lymphoma are increased in incidence in patients with rheumatoid arthritis.

The treatment of EORA presents special challenges. First, a patient with RA past the age of 60 probably has other medical conditions. Second, they are probably on multiple medications. The diagnosis may be confounded by the fact the both ESR and rheumatoid factor can be elevated in older patients who don't have RA. Finally, treatment with medications needs to be tempered with the knowledge that potential side-effects may be increased in this population where drug metabolism is less certain than that of younger patients.

Nonetheless, the approach to therapy for patients with EORA is not substantially different from the treatment strategies employed for younger patients.

Non-steroidal anti-inflammatory drugs (NSAIDS) are often used early on in younger patients. However, in older patients who may develop kidney and liver toxicity with these agents, the use of NSAIDS is probably a strategy that has to be watched closely.

Low dose prednisone (5-10mgs) given as a single morning dose provides symptomatic relief and can serve as a "bridge" until the effects of second line agents begin. The potential complications of long-term prednisone therapy such as osteoporosis and cataracts, among others, will be more of a concern than for younger patients.

Second line agents consist of two groups. They are the disease-modifying anti-rheumatic drugs (DMARDS) and the biologic drugs.

Disease-modifying drugs such as methotrexate, hydroxychloroquine (Plaquenil), sulfasalazine (Azulfidine), and leflunomide (Arava) are all potentially useful. Obviously, with older patients, potential toxicities and drug interactions need to be monitored for carefully.

Biologic therapies can also be used for patients with EORA. TNF inhibitors such as etanercept (Enbrel), adalimumab (Humira), infliximab (Remicade, and the two newer agents golimumab (Simponi), and certolizumab (Cimzia) are all effective and well tolerated in the older population of patients with rheumatoid arthritis.

Second line biologics such as rituximab (Rituxan) and abatacept (Orencia) have also been used in patients with EORA with results comparable to that for younger patients.

Advancing age should not, by itself, be a contraindication to the use of biologic therapies. The aim for older patients, as it is with younger patients, is to establish remission. This may be even more important in older patients since independence is cherished more. Finally, since cardiovascular events are an established complication of rheumatoid arthritis and are also more common in older adults, every effort should be instituted to establish and maintain remission.