Assessment of the Risk of Stroke or Blindness in Giant Cell Arteritis

Abstract & Commentary

Source: Nesher G, Berkun Y, Mates M, et al. Risk factors for cranial ischemic complications in giant cell arteritis. Medicine. 2004;83:114-122.

Central nervous system (CNS) ischemic complications including visual loss and stroke are the most dreaded manifestations of giant cell arteritis (GCA). Ischemic complications can be among the presenting manifestations of GCA or can develop at a later stage despite steroid treatment. The incidence of visual loss during the first year of steroid therapy has been reported to be as high as eight percent.1 Similarly, stroke can occur soon after the beginning of steroid therapy. In one study,2 7 of 8 GCA patients with strokes were already receiving steroids, and the median interval between the start of steroid therapy and stroke onset was 10 days.

In order to identify risk factors for CNS ischemic complications at presentation and during follow-up, Nesher and associates reviewed the charts of 175 patients with GCA diagnosed between 1980 and 2000 at 4 Jerusalem hospitals. In 25% (n = 43) GCA presented with CNS complications. Thirty-two (18%) had acute loss of vision: 26 had anterior ischemic optic neuropathy (AION) and 6 had central retinal artery occlusion. Thirteen (7%) presented with strokes and 2 of them had a stroke and AION within 24 hours

Thirty-four percent of the patients with visual loss and 77% of the stroke patients had other GCA-related symptoms at the time of diagnosis. Transient ischemic attacks (TIA), visual or cerebral, were reported by 33 patients, half of whom (n = 17) eventually experienced persistent CNS ischemic complications. At presentation significant risk factors for CNS ischemic complications were TIA (odds ratio [OR], 4.3) and male sex (OR, 2.5). There was no significant association between CNS ischemic complications and the presence of diabetes, hypertension or hyperlipidemia, age, platelet count, hemoglobin level and ESR. The presence of systemic GCA-related symptoms (polymyalgia rheumatica, fever, fatigue, or anorexia) and the use of aspirin (100 mg/d) were associated with a lower risk (OR, 0.3).

Following the diagnosis of GCA and the initiation of steroid therapy, 14 of 166 patients (8%) developed CNS ischemic complications: 8 had vision loss and 6 had strokes. Risk factors in these patients were a previous CNS ischemic complication at presentation (OR, 5.6) and TIAs during followup (OR, 14.8). The use of low-dose aspirin was protective (OR, 0.2).

Commentary

In agreement with other studies, Nesher and colleagues found that the presence of systemic symptoms was associated with a protective effect against CNS ischemic complications. The protective effect of fever was the most significant but its mechanism is unknown. There was no association between stroke or visual loss and jaw claudication or the results of standard laboratory tests of inflammation. The role of antiphospholipid antibodies and homocysteine in GCA-related CNS ischemia was not evaluated.

The good news from this study is that aspirin therapy during the follow-up period was protective.

Nesher et al have shown that GCA patients can be stratified into high- and low-risk groups for developing CNS ischemic complications. Future studies will be needed to determine whether high-risk patients might benefit from a more aggressive treatment approach including higher doses of steroids and possibly the addition of multiple antiplatelet agents. — John J. Caronna

Dr. Caronna, Vice-Chairman, Department of Neurology, Cornell University Medical Center; Professor of Clinical Neurology, New York Hospital, is Associate Editor of Neurology Alert.

References

1. Hoffman GS, et al. Arthritis Rheum. 2002;46: 1309-1318.

2. Gonzalez-Gay MA, et al. Arthritis Rheum. 1998;41:1497-1504.