Porth's Essentials of Pathophysiology, 4e

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Musculoskeletal Function

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High serum urate levels rarely occur in women before menopause; initial attacks of clinical gout occur around the age of 70 years, or 20 years after menopause. The treatment of gout is often more difficult in the elderly. Although colchicine may be effective in controlling the symptoms of chronic gout, it may cause diarrhea in some patients, limiting its effectiveness in maintenance therapy. Pseudogout. As part of the tissue aging process, OA develops with associated cartilage degeneration and the shedding of calcium pyrophosphate crystals into the joint cavity. These crystals may produce a low-grade chronic inflammation—the chronic pseudogout syn- drome. The accumulation of calcium pyrophosphate and related crystalline deposits in articular cartilage is common in the elderly. There are no medications that can remove the crystals from the joints. Although it may be asymptomatic, presence of the crystals may contrib- ute to more rapid cartilage deterioration. This condition may coexist with severe OA. Calcium pyrophosphate deposition disease may also present with proximal mus- cle pain mimicking polymyalgia rheumatica. Polymyalgia Rheumatica Polymyalgia rheumatica is an inflammatory condition of unknown origin characterized by aching and morn- ing stiffness in the cervical regions and shoulder and pel- vic girdle areas. 86–88 Of the forms of arthritis affecting the elderly, it is one of the more difficult to diagnose and one of the most important to identify. Elderly women are especially at risk. Polymyalgia rheumatica is a com- mon syndrome of older persons, rarely occurring before 50 years of age (and usually after age 60). The onset can be abrupt, with the patient going to bed feeling well and awakening with pain and stiffness in the neck, shoul- ders, and hips. Diagnosis and Treatment. Diagnosis is based on the pain and stiffness persisting for at least 1 month and an elevated ESR. The diagnosis is confirmed when the symptoms respond dramatically to a small dose of pred- nisone, a corticosteroid. Biopsies have shown that the muscles are normal, despite the name, but that a non- specific inflammation affecting the synovial tissue is present. It is possible that a number of patients are erro- neously diagnosed as having RA or OA. For patients with an elevated ESR, the diagnosis usually is based on a 3-day trial of prednisone treatment. 87 Patients with polymyalgia rheumatica typically exhibit striking clini- cal improvement on the second day. Patients with RA also show improvement, although usually days later. Treatment with NSAIDs provides relief for some patients, but most require continuing therapy with prednisone, with gradual reduction of the dose over the course of 1.5 to 2 years, using the person’s symp- toms as the primary guide. Patients need close moni- toring during the maintenance phase with prednisone therapy. Because their symptoms are relieved, they often quit taking the prednisone and their symptoms recur, or doses are missed and the decreased dosage leads to an increase in symptoms. Unless careful assessment reveals

the frequency of missed doses, the physician may be misled into increasing the dosage when it is not needed. Because of the side effects of the corticosteroids, the goal is to use the lowest dose of the drug necessary to control the symptoms. Weaning patients off low-dose predni- sone therapy after this length of time can be a difficult and extended process. Complications. A certain percentage of patients with polymyalgia rheumatica also develop giant cell arteritis (i.e., temporal arteritis) with involvement of the oph- thalmic arteries. 89 The two conditions are considered to represent different manifestations of the same disease. Giant cell arteritis, a form of systemic vasculitis, is a sys- temic inflammatory disease of large and medium-sized arteries. The inflammatory response seems to be a T-cell response to an antigen. Clinical manifestations of giant cell arteritis usually begin insidiously and may exist for some time before being recognized. 89 It is potentially dangerous if missed or mistreated, especially if the temporal artery or other vessels supplying the eye are involved, in which case blindness can ensue quickly without treatment. The condition is responsive to appropriate therapy. For those patients at risk, adherence to the medication pro- gram is critical, with preservation of sight being the goal. Because this complication can occur so quickly and is relatively asymptomatic, it is vital that the patient understand the importance of taking the correct dose regularly as prescribed. Initial treatment consists of large doses of prednisone. This dosage is continued for 4 to 6 weeks and then decreased gradually. In addition to diagnosis-specific treatment, the elderly require special considerations. 82 Management tech- niques that rely on modalities other than drugs are particularly important. These include splints, walking aids, muscle-building exercise, and local heat. Muscle- strengthening and stretching exercises are particularly effective in the elderly person with age-related losses in muscle function and should be instituted early. Rest, the cornerstone of conservative therapy, is hazardous in the elderly, who can rapidly lose muscle strength. In terms of medications, the NSAIDs may be less well tolerated by the elderly, and their side effects are more likely to be serious. In addition to bleeding from the gastrointestinal tract and renal insufficiency, there may be cognitive dysfunction manifested by forgetful- ness, inability to concentrate, sleeplessness, paranoid ideation, and depression. Joint arthroplasty can also be used for pain relief and increased function. Chronologic age is not a contraindi- cation to surgical treatment of arthritis. In appropriately selected elderly candidates, survival and functional out- come after surgery are equivalent to those in younger age groups. The more sedentary activity level of the elderly makes them even better candidates for joint replacement because they put less stress and demand on the new joint. Management of Rheumatic Diseases in the Elderly