In the JournalsPerspective

Study shows correlation between HDL, triglycerides and AMD

HDL cholesterol and triglycerides have a positive and negative association, respectively, with an increased risk of age-related macular degeneration, particularly in the early stages, according to a study.

The correlation between circulating lipid levels and AMD, as well as the association with specific genetic variants, were analyzed in a large dataset from the European EYE-RISK project, involving 14 studies in seven countries.

This study, like several other studies, was triggered by the notion that drusen are deposits of lipid-rich proteins, resembling the formation of artherosclerotic plaques in cardiovascular disease. Systemic lipid levels, as well as specific genes involved in lipid metabolism, may therefore have significant correlations with drusen and early AMD disease.

A total of 4,730 individuals with early AMD, 2,441 with late AMD and 23,782 nonaffected subjects were identified within the EYE-RISK database. Lipid levels as well as genotype data were recorded.

A positive association was found between higher HDL cholesterol and an increased risk of any AMD, with slightly higher estimates for early AMD. Conversely, triglycerides were negatively associated with early AMD and any AMD. The same correlations were found with drusen size and area: Higher HDL levels were associated with greater drusen size and area whereas higher triglycerides were associated with smaller drusen size and area. Genetic analysis did not lead to clear-cut answers.

“The more pronounced risk for early AMD and increasing [odds ratios] of HDL cholesterol for the larger drusen suggest that lipids play an important role at the early phase of disease. Hypothetically, intervention at this phase would be most promising in preventing blindness,” the authors wrote.

“Whether systemic lipids directly influence lipid metabolism in the retina or whether these lipids mirror pathologic features in the retina is a question that remains to be answered,” they concluded. – by Michela Cimberle

Disclosure: Colijn reported no relevant financial disclosures. Please see the published paper for the other authors’ financial disclosures.

HDL cholesterol and triglycerides have a positive and negative association, respectively, with an increased risk of age-related macular degeneration, particularly in the early stages, according to a study.

The correlation between circulating lipid levels and AMD, as well as the association with specific genetic variants, were analyzed in a large dataset from the European EYE-RISK project, involving 14 studies in seven countries.

This study, like several other studies, was triggered by the notion that drusen are deposits of lipid-rich proteins, resembling the formation of artherosclerotic plaques in cardiovascular disease. Systemic lipid levels, as well as specific genes involved in lipid metabolism, may therefore have significant correlations with drusen and early AMD disease.

A total of 4,730 individuals with early AMD, 2,441 with late AMD and 23,782 nonaffected subjects were identified within the EYE-RISK database. Lipid levels as well as genotype data were recorded.

A positive association was found between higher HDL cholesterol and an increased risk of any AMD, with slightly higher estimates for early AMD. Conversely, triglycerides were negatively associated with early AMD and any AMD. The same correlations were found with drusen size and area: Higher HDL levels were associated with greater drusen size and area whereas higher triglycerides were associated with smaller drusen size and area. Genetic analysis did not lead to clear-cut answers.

“The more pronounced risk for early AMD and increasing [odds ratios] of HDL cholesterol for the larger drusen suggest that lipids play an important role at the early phase of disease. Hypothetically, intervention at this phase would be most promising in preventing blindness,” the authors wrote.

“Whether systemic lipids directly influence lipid metabolism in the retina or whether these lipids mirror pathologic features in the retina is a question that remains to be answered,” they concluded. – by Michela Cimberle

Disclosure: Colijn reported no relevant financial disclosures. Please see the published paper for the other authors’ financial disclosures.

    Perspective
    Brad Sutton

    Brad Sutton

    HDL cholesterol is often referred to as “good cholesterol,” as it seems to serve as a scavenger of sorts that captures LDL, otherwise known as “bad cholesterol,” and carries it to the liver to be metabolized. So from a cardiovascular standpoint, high levels of HDL are typically regarded as being positive. However, some recent studies have indicated a possible link between very high HDL and increased cardiovascular mortality risk.

    Could higher levels of HDL also be associated with macular degeneration? This study seems to indicate that they may indeed be, in the form of increased drusen formation, especially when considering high concentrations of extra-large HDL particles. Perhaps this is not entirely surprising, as drusen can consist of up to 40% lipid. The study also found that increasing LDL levels were not associated with AMD, and that increasing levels of triglycerides were actually associated with decreasing AMD risk.

    So what does this mean for optometrists? When we see a patient with drusen, in addition to advising them about smoking cessation, diet, exercise and AREDS supplements where appropriate, perhaps we should also be advising them to have their cholesterol levels checked.

    • Brad Sutton, OD, FAAO
    • Clinical professor, Indiana University School of Optometry
      Service chief, Indianapolis Eye Care Center

    Disclosures: Sutton reported no relevant financial disclosures.