Monday, April 4, 2011

Abdominal obesity is a risk factor for AMD in middle aged men

Increasing weight in middle aged men could significantly increase the risk of blindness later in life, a study has found.

Melbourne University researchers, in a study that monitored changes in the waistlines of more than 21,000 men and women between 40 and 69 over several years, have noted that an expanding waistline puts men in danger of developing age-related macular degeneration (AMD), which is a leading cause of vision loss in the elderly. Even a small increase in waistline increases the risk of developing AMD. The researchers found that even for an increase of 0.1 in the waist/hip ratio, a man's chances of developing the disease soared by 75 per cent.

Women do not appear to be as affected as men, as found in this study, possibly due to pre-existing high levels of female hormone oestrogen acting as a preventive factor.

Digestion of abdominal fat releases oestrogen, which can cause inflammation in blood vessels at the back of the eyes. Such inflammation is considered to be one of the factors in developing AMD.

The disease is caused by the growth of new and abnormal blood vessels under the macula, a small oval-shaped area in the retina, which is an important part of the visual system in helping us see objects and print clearly. These abnormal blood vessels leak fluid, causing scar tissue to form and destroying vision in the centre of the eye. This makes it difficult to recognise faces, read or watch TV.

Around 90 per cent of cases develop dry AMD, a form of the disease which gradually progresses over many years, and for which there is no treatment currently. The rest of the cases develop wet AMD, which can progress fast and can quickly lead to blindness.

The current standard treatment involves monthly injections of agents, which can reduce the chances of developing the abnormal blood vessels, into the back of the eye. Given early enough, it can help to prevent complete loss of vision.

Research suggests eating healthy, with regular intake of fruit, vegetables and nuts in the diet, can reduce disease rates by up to 20 per cent. Also, eating chicken three times a week has been found to reduce the risk by half.

The article is sourced from here.