Neovascular Age-Related Macular Degeneration and the Risk of Stroke

Abstract

Background and Purpose-Using a nationwide population-based data set from Taiwan, this study investigated the relationship between neovascular age-related macular degeneration (AMD) and the risk of stroke over a 5-year period. Method-The study cohort comprised 209 patients who received treatment for AMD between 1999 and 2001. We randomly selected 1045 subjects matched with the study cohort in terms of age and gender for comparison. Cox proportional hazard regressions were performed to compare the 5-year stroke-free survival rate. Results-Among the sampled patients, 142 patients (11.3%) had strokes during the 5-year follow-up period, 38 (18.2% of the patients with AMD) from the study cohort and 104 (9.9% of patients in the comparison cohort) from the comparison cohort. After adjusting for the patient's age, gender, monthly income, level of urbanization, and the geographic region of the community in which the patient resided and comorbidities, the hazard ratio for stroke during the follow-up period was 2.01 (Pϭ0.001) times greater for patients with AMD than for patients without AMD. The adjusted hazard ratio for stroke during the follow-up period was 2.21 (Pϭ0.001) times higher for patients with AMD Ն65 years old compared with the same age group in the comparison cohort. However, no significant difference was observed in the risk of stroke between patients with AMD Ͻ65 years of age and comparison patients in the same age group. Conclusion-We conclude that neovascular AMD is associated with a higher risk of stroke for patients with AMD Ն65 years old. (Stroke. 2010;41:613-617.)

Age-Related Macular Degeneration and the Risk of Stroke

“…9 The Blue Mountains Eye Study found that early and late AMD were not associated with stroke mortality, 10 whereas a study from Taiwan found that neovascular AMD increased the risk of stroke-related death. 7 Only 1 study divided stroke into subtypes and found that the risks of both cerebral infarction and intracerebral hemorrhage were increased in people with either neovascular or nonneovascular AMD. 8 However, a limitation of the study was that the classification of stroke and AMD were both based on medical reimbursement claims and therefore vulnerable to misclassification.…”

“…3 Previous studies that investigated the association between AMD and stroke reported inconsistent results. [7][8][9][10][11] Most studies did not distinguish between early and late AMD nor did they subdivide late AMD into dry (atrophic) or wet (neovascular) AMD. Besides, except for a study based on medical reimbursement claims, no previous study presented separate associations for the subtypes cerebral infarction and intracerebral hemorrhage.…”

Age-Related Macular Degeneration

“…6 In the current issue of Stroke, Hu and colleagues further report on this association. 8 Using a national linkage database in Taiwan, the authors showed that patients with a neovascular AMD diagnosis had a 2-fold higher incidence of stroke than those without AMD (18.2% versus 9.9%), and this association persisted while controlling for concomitant vascular risk factors. One of the strengths of this study is the ability to study neovascular AMD cases; in population-based studies like the ARIC cohort, there were few late neovascular AMDs.…”

Arterial Thromboembolic Events in Patients with Exudative Age-Related Macular Degeneration Treated with Intravitreal Bevacizumab or Ranibizumab

“…In 15,771 new-onset neovascular AMD patients aged ≥65 years matched with 46,408 controls, Alexander et al [35] found similar rates of myocardial infarction and ischemic cerebral vascular accidents among neovascular AMD patients and controls. More recently, Hu et al [36] found in 209 neovascular AMD patients from Taiwan and 1,045 matched controls during a 5-year follow-up period a hazard ratio for stroke 2.01 times greater for patients with AMD than for patients without AMD. However, no significant difference was found between patients with AMD <65 years of age and age-matched controls [36].…”

“…More recently, Hu et al [36] found in 209 neovascular AMD patients from Taiwan and 1,045 matched controls during a 5-year follow-up period a hazard ratio for stroke 2.01 times greater for patients with AMD than for patients without AMD. However, no significant difference was found between patients with AMD <65 years of age and age-matched controls [36]. As can be easily inferred from the above results, an association between neovascular AMD and stroke, myocardial infarction or cardiovascular disease is likely, but this link needs to be further investigated.…”