Mortality in Patients with Branch Retinal Vein Occlusion Nynne Christoffersen, MD, 1,2 Else Gade, MD, 3 Lars Knudsen, MD, DMSc, 4 Knud Juel, PhD, 5 Michael Larsen, MD, DMSc 1,2 Purpose: To assess the impact of branch retinal vein occlusion (BRVO), a condition related to arteriolar wall thickening, as a prognostic marker of mortality. Design: Long-term follow-up study comparing cases with background population. Participants: Patients diagnosed with BRVO. Methods: Diagnosis of BRVO confirmed by fundus photographic records including color diapositives and fluorescein angiograms. Main Outcome Measures: Observed and expected numbers of deaths determined from comprehensive civic records in cases compared with the background population (5.4 million). Results: Branch retinal vein occlusion was found in 329 patients (173 women, 156 men) born between 1902 and 1956, who were 39 to 91 years old when diagnosed between 1973 and 1998. Follow-up was concluded on July 8, 2004, when 144 deaths were recorded in patients (74 women, 70 men), compared with an expected number of 145.5 deaths in the background population (standardized mortality rate, 0.99; 95% confidence interval, 0.84 –1.16). Stratified analyses revealed no significant effect of age, gender, or time of diagnosis. Conclusions: In this study of 329 patients with BRVO, we found no significant difference in mortality between patients and the background population. An association between BRVO and cardiovascular/cerebro- vascular risk factors has previously been documented in cross-sectional studies. The contrasting outcome in this longitudinal study may have been influenced by interventions instituted after the diagnosis of BRVO was made and by preferential survival before the diagnosis of BRVO of the more fit patients with the necessary precursor condition of having arteriovenous nicking, which is more prevalent in subjects with diabetes and hypertension. Ophthalmology 2007;114:1186 –1189 © 2007 by the American Academy of Ophthalmology. Branch retinal vein occlusion (BRVO) is a frequent cause of eye disease in the middle aged and elderly. The occlusion is caused by venous compression exerted by a thickened ret- inal artery crossing in front of the vein. Hence, it is primar- ily a consequence of arterial disease, with only a minor role being attributable to coagulopathy. Documented risk factors include arterial hypertension, 1–4 diabetes mellitus, 3,4 smok- ing, 4 higher body mass index, 3 male gender, 1–3 hyperhomo- cysteinemia, 5 higher  2 -globulin, 3 higher activated factor VII, 6 increased blood viscosity, 7 hypermetropia, 8,9 and open-angle glaucoma. 2,3 Absence of BRVO has been asso- ciated with elevated high-density lipoprotein levels and higher levels of alcohol consumption. 3 Consequently, BRVO would appear likely to be associated with increased mortality. We tested this hypothesis by examining the mor- tality of patients with BRVO in relation to that of the background population. Materials and Methods Fundus photographic records, including color diapositives and fluorescein angiograms, were retrieved for patients diagnosed with BRVO at 2 secondary referral centers in the Danish cities of Copenhagen and Odense. Patients registered with the International Classification of Diseases 10 diagnosis H34.8 were identified, and all available fundus photographs and fluorescein angiograms from these patients were reviewed. A retina specialist validated the diagnosis, accepting only cases in which an unequivocal diagnosis of BRVO could be made. Diagnostic criteria were branch vein compression at an arteriovenous crossing, with upstream vascular congestion, hemorrhage, ischemia, and edema and collaterals lead- ing to adjacent branch veins, in the absence of comparable changes in adjacent vascular drainage units. In long-standing cases, con- gestion, edema, and hemorrhage needed not be present, whereas such cases were expected to show a more prominent fibrosis of the segment of the branch vein immediately upstream of the occlusion site. The presence of diabetic retinopathy was accepted if found in both eyes. Cases were identified by the unique social security Originally received: September 18, 2005. Accepted: January 9, 2007. Manuscript no. 2005-884. 1 Department of Ophthalmology, Glostrup Hospital, University of Copen- hagen, Copenhagen, Denmark. 2 Kennedy Institute–National Eye Clinic, Hellerup, Denmark. 3 Department of Ophthalmology, Odense University Hospital, Odense, Denmark. 4 Department of Ophthalmology, Aalborg Hospital, Aalborg, Denmark. 5 National Institute of Public Health, Hellerup, Denmark. Supported by the Værn Om Synet, Copenhagen, Denmark, and Juvenile Diabetes Research Foundation, New York, New York (Patient-Oriented Diabetes Research Career Award, grant no. 8-2002-130 [ML]). The authors have no relevant financial or proprietary interest in any aspect of the study. Correspondence to Michael Larsen, Department of Ophthalmology, Glostrup Hospital, DK-2600 Glostrup, Denmark. E-mail: mla@dadlnet.dk. 1186 © 2007 by the American Academy of Ophthalmology ISSN 0161-6420/07/$–see front matter Published by Elsevier Inc. doi:10.1016/j.ophtha.2007.01.031