MyVisionTest News Archive
Aug 22, 2008
Evidence supports link between AMD, cardiovascular disease
Ocular Surgery News reports that results of four studies suggest that ophthalmologists and cardiologists should consider common risk factors for age-related macular degeneration (AMD) and cardiovascular disease.
Cross-disciplinary awareness of the shared risk factors between cardiovascular disease and AMD is important in treating patients with either disease. Researchers, however, appear to differ on the degree of association.
"More data supporting the association between cardiovascular disease (CVD) and late stages of AMD are continuing to emerge," Dr Usha Chakravarthy said.
"Better vascular compliance and regulation of the ocular circulation through improved and early management of the systemic manifestations of cardiovascular disease could in the long term prove beneficial in reducing the risk of development of the late stages of AMD," she said.
Evidence for a link between CVD and AMD has been building over the past 10 years as researchers have added to the list of possible common risk factors. Recent studies have shown a link between CVD and AMD, and blood pressure, body mass index and cholesterol.
"One of the likely common pathways would be [the] inflammatory process," Dr Jie Jin Wang said.
"Other possible pathways could involve antioxidants and omega-3 fatty acids, but the exact mechanisms are less clear," she said.
Research remains largely inconclusive, as some investigators find connections between risk factors, while others do not. Most experts agree that a link likely exists, and so neither ophthalmologists nor cardiologists can ignore the common factors across their specialties.
In a study published in the British Journal of Ophthalmology, Dr. Wang and colleagues showed that AMD patients aged 49 to 75 years were at a higher risk of having a stroke or other cardiovascular event.
Specifically, the investigators followed 1,952 older Australians recruited in the longitudinal Blue Mountains Eye Study, led by Dr Paul Mitchell for 10 years. They found that early AMD predicted a twofold higher risk of cardiovascular mortality, controlling for cardiovascular risk factors, whereas late AMD predicted a fivefold higher risk of cardiovascular mortality, controlling for age and sex.
In a study published in Ophthalmology, the same investigators found that a self-reported history of stroke and any CVD at baseline (1992 to 1994) in the same study population predicted early AMD development over the next 10 years.
Similarly, in a case-control study involving more than 400 participants, Dr. Chakravarthy and colleagues found that the odds of having a history of existing CVD were far higher in cases of neovascular AMD than in controls. Their results were published in Ophthalmology.
"Our study cannot confirm causality, but it is strongly suggestive," she said.
Recent studies have found cholesterol, body mass and hypertension to be associated with AMD development.
In a separate study, Dr Rohit Varma and colleagues evaluated the link between CVD and AMD in a Latino population. Their results were published in the American Journal of Ophthalmology.
In a population-based sample of 5,875 Latino patients, rates of high diastolic blood pressure and uncontrolled diastolic hypertension were higher among patients with exudative AMD, they reported.
"One essential piece of evidence that is needed before one can begin to plan clinical trials and intervention programs is that you want to have some common factors that you can address across the board, not just in one ethnic group but in different ethnic groups," Dr. Varma said.
"What we have provided is additional evidence from a completely different ethnic group that supports some of the findings that were seen in non-Hispanic whites, and thus it strengthens the case that can be made for smoking and blood pressure and perhaps indirectly inflammation and its role in the development of advanced AMD," he said.
In the meantime, researchers have begun to consider the existence of CVD-related therapeutic tactics for AMD patients.
"A preliminary impression at this stage is that what is good for the heart appears also to be good for the eye," Dr. Wang said. "These would include antioxidants, omega-3 fatty acids and reduced glycemic index diet.
"Advising patients to lead a healthier lifestyle, including diet, exercise and approaches to minimize CVD risk factors, will be good for the heart as well as for the eye," she said.
Dr. Varma agreed on the use of antioxidants and also mentioned zinc as a possible useful dietary supplement for patients at high risk for AMD. Additionally, he said patients may reduce their risk of developing AMD by quitting smoking and controlling their blood pressure. He noted that more evidence is needed to definitively link smoking and blood pressure to AMD, but "those two areas have been the most consistent ones in most studies."
"The other thing, which is still very much in an early stage, is that in the last few years, researchers have identified a group of genes — the CFH gene complex (complement factor H) — which is related to an inflammatory pathway," Dr. Varma said.
"If inflammation is related to AMD, and it appears to be, then would it be valuable to use anti-inflammatory medications directed specifically at this pathway to lower the risk of developing advanced AMD?" he said, adding that this cutting-edge research is an area that deserves attention in the future.
Read more...
OSN SuperSite
Tags: AMD, obesity, fish, diet, cardiovascular disease
Ocular Surgery News reports that results of four studies suggest that ophthalmologists and cardiologists should consider common risk factors for age-related macular degeneration (AMD) and cardiovascular disease.Cross-disciplinary awareness of the shared risk factors between cardiovascular disease and AMD is important in treating patients with either disease. Researchers, however, appear to differ on the degree of association.
"Better vascular compliance and regulation of the ocular circulation through improved and early management of the systemic manifestations of cardiovascular disease could in the long term prove beneficial in reducing the risk of development of the late stages of AMD," she said.
Evidence for a link between CVD and AMD has been building over the past 10 years as researchers have added to the list of possible common risk factors. Recent studies have shown a link between CVD and AMD, and blood pressure, body mass index and cholesterol.
"One of the likely common pathways would be [the] inflammatory process," Dr Jie Jin Wang said.
"Other possible pathways could involve antioxidants and omega-3 fatty acids, but the exact mechanisms are less clear," she said.
Research remains largely inconclusive, as some investigators find connections between risk factors, while others do not. Most experts agree that a link likely exists, and so neither ophthalmologists nor cardiologists can ignore the common factors across their specialties.
In a study published in the British Journal of Ophthalmology, Dr. Wang and colleagues showed that AMD patients aged 49 to 75 years were at a higher risk of having a stroke or other cardiovascular event.
Specifically, the investigators followed 1,952 older Australians recruited in the longitudinal Blue Mountains Eye Study, led by Dr Paul Mitchell for 10 years. They found that early AMD predicted a twofold higher risk of cardiovascular mortality, controlling for cardiovascular risk factors, whereas late AMD predicted a fivefold higher risk of cardiovascular mortality, controlling for age and sex.
In a study published in Ophthalmology, the same investigators found that a self-reported history of stroke and any CVD at baseline (1992 to 1994) in the same study population predicted early AMD development over the next 10 years.
Similarly, in a case-control study involving more than 400 participants, Dr. Chakravarthy and colleagues found that the odds of having a history of existing CVD were far higher in cases of neovascular AMD than in controls. Their results were published in Ophthalmology.
"Our study cannot confirm causality, but it is strongly suggestive," she said.
Recent studies have found cholesterol, body mass and hypertension to be associated with AMD development.
In a separate study, Dr Rohit Varma and colleagues evaluated the link between CVD and AMD in a Latino population. Their results were published in the American Journal of Ophthalmology.
In a population-based sample of 5,875 Latino patients, rates of high diastolic blood pressure and uncontrolled diastolic hypertension were higher among patients with exudative AMD, they reported.
"One essential piece of evidence that is needed before one can begin to plan clinical trials and intervention programs is that you want to have some common factors that you can address across the board, not just in one ethnic group but in different ethnic groups," Dr. Varma said.
"What we have provided is additional evidence from a completely different ethnic group that supports some of the findings that were seen in non-Hispanic whites, and thus it strengthens the case that can be made for smoking and blood pressure and perhaps indirectly inflammation and its role in the development of advanced AMD," he said.
In the meantime, researchers have begun to consider the existence of CVD-related therapeutic tactics for AMD patients.
"A preliminary impression at this stage is that what is good for the heart appears also to be good for the eye," Dr. Wang said. "These would include antioxidants, omega-3 fatty acids and reduced glycemic index diet.
"Advising patients to lead a healthier lifestyle, including diet, exercise and approaches to minimize CVD risk factors, will be good for the heart as well as for the eye," she said.
Dr. Varma agreed on the use of antioxidants and also mentioned zinc as a possible useful dietary supplement for patients at high risk for AMD. Additionally, he said patients may reduce their risk of developing AMD by quitting smoking and controlling their blood pressure. He noted that more evidence is needed to definitively link smoking and blood pressure to AMD, but "those two areas have been the most consistent ones in most studies."
"The other thing, which is still very much in an early stage, is that in the last few years, researchers have identified a group of genes — the CFH gene complex (complement factor H) — which is related to an inflammatory pathway," Dr. Varma said.
"If inflammation is related to AMD, and it appears to be, then would it be valuable to use anti-inflammatory medications directed specifically at this pathway to lower the risk of developing advanced AMD?" he said, adding that this cutting-edge research is an area that deserves attention in the future.
Read more...
OSN SuperSite
