RESEARCH · September 09, 2014
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- This prospective cohort study sought to establish a connection between metabolic syndrome and age-related macular degeneration (AMD). Over a 10-year period, 2218 individuals >49 years of age with metabolic syndrome were followed for the development of early and late AMD. Early AMD developed in 12% and late AMD in 3% of participants. In those This study has implications not only for elucidating the etiology of AMD, but also the effects that lifestyle modifications may have.
Expert Comment
Eye Care
Paul B Freeman OD, FAAO, FCOVD
Almost every article on the topic of age-related macular degeneration (AMD) begins with a statement of the fact that AMD “is the leading cause of blindness and poor vision.” That comment alone is the reason for the seemingly excessive numbers of articles about macular degeneration and the extensive research devoted to assessing, treating, and remediating this condition. Because typically it follows that advancing age is one of the primary causative factors, it is of interest that a study looks at AMD specifically in those who are 70 years old and younger to determine if there might be a relationship between the constellation of metabolic irregularities termed metabolic syndrome (MetS) and the possibly predictable risk of advancing to late-stage AMD (both neovascular and geographic AMD). In an article published recently in Retina, Maralani and colleagues used the population data from the Blue Mountain Eye Study (BMES) to evaluate the relationship between MetS (obesity plus any two of the following: increased serum triglyceride levels, increased serum HDL cholesterol, hypertension, and increased fasting plasma glucose) and progression to late-stage AMD over a 10-year period.1 To do that, they established baseline data of both retinal health (those without evidence of AMD at baseline) and general health as related to MetS components. They then reassessed the relationship between late-stage AMD and the variable of MetS at 5- and 10-year markers. The authors found that the subset of MetS that included obesity, high glucose, and high triglycerides was predictive of progression to late-stage AMD in the study population. Also of interest, the authors found that there was no relationship “between MetS and its components with early AMD….”
There is no secret that visual impairment (associated with late-stage AMD as well as other pathologies) can cause a decrease in quality of life as well as an increased risk for mortality.2 However, there are variables related to the risk of developing macular degeneration as well as to the risk of progressing to late-stage AMD which, if successfully modified, can mitigate some of the negative effects of this pathology. These modifiable factors include nutrition (diet, supplements, weight control, and alcohol consumption), smoking cessation, exercise, UV light exposure, and certain health issues like MetS. While it is not always easy for people to positively alter these variables, it is vitally important for all healthcare professionals to educate their patients about the risks related to AMD and then to support interventions that can minimize those risks. As a bonus, if those variables determined by the authors as increasing the risk for advancing to late-stage AMD can be diminished, it might follow that the risk for developing other MetS-related health concerns (specifically cardiovascular disease, diabetes, and stroke) could be reduced as well.
References
Ghaem Maralani H, Tai BC, Wong TY, et al. Metabolic Syndrome and Risk of Age-Related Macular Degeneration [published online ahead of print September 9, 2014]. Retina. doi: 10.1097/IAE.0000000000000338.
Zheng DD, Christ SL, Lam BL, et al. Increased Mortality Risk among the Visually Impaired: The Roles of Mental Well-Being and Preventive Care Practices. Investigative Ophthalmology & Visual Science. 2012;53(6):2685-2692.
ABSTRACT
PURPOSE
To investigate the relationship between metabolic syndrome (MetS) and its components with the risk of early- and late-stage age-related macular degeneration (AMD).
METHODS
A prospective cohort of individuals aged older than or equal to 49 years were followed up over a period of 10 years in the Blue Mountains Eye Study, Australia. MetS components were measured at baseline (1992-1994), 5-year (1997-1999), and 10-year (2002-2004) follow-ups. Incident cases of early and late AMD were diagnosed using standard photographic grading of retinal images of 2,218 participants at risk. Mixed-effect logistic regression was conducted to explore the relationship between MetS (and its components) with subsequent development of early/late AMD.
RESULTS
Over the 10-year follow-up, early AMD developed in 12% and late AMD in 3% of participants at risk. Amongst subjects aged younger than or equal to 70 years, MetS was associated with the incidence of late AMD. Of the five MetS components, obesity, high glucose, and high triglyceride were associated with the increased incidence of late AMD during the 10-year follow-up. There was no evidence of effect of MetS and its components on the risk of early AMD.
CONCLUSION
Metabolic syndrome, obesity, high glucose, and high triglycerides were predictors of progression to late AMD. These data provide additional insights into the pathogenesis of AMD.
Retina (Philadelphia, Pa.)
Metabolic Syndrome and Risk of Age-Related Macular Degeneration