Smoking has blinded 1300 NZers, study finds

By MARTIN JOHNSTON and ANGELA GREGORY

Smoking has blinded more than 1300 New Zealanders, says medical research published today.

One of the researchers, Dr Nick Wilson, said yesterday that 400 people each year needed cataract surgery also because of smoking.

The findings, published in the New Zealand Medical Journal, call for tobacco packets to carry warnings on smoking and blindness.

The Health Ministry said it would consider this, but the Government had given it other priorities in tobacco control.

Dr Wilson, a Wellington independent public health physician, said the 1300 who had been blinded - most of them fully - by smoking suffered from a condition called age-related Macular degeneration (AMD), which had cost more than 5200 New Zealanders their eyesight.

The macula is the part of the eye that distinguishes fine detail at the centre of the field of vision.

Most AMD cases cannot be treated, but laser treatment will sometimes limit the loss of vision.

Dr Wilson said AMD was the main cause of blindness in those aged over 55. Ageing itself was one of the causes of the condition.

"Smoking accelerates the whole ageing process. The damaging chemicals in tobacco smoke possibly have an effect."

Smokers' bodies also had lower levels of anti-oxidants, which helped maintain good health.

The article also says toxic heavy metals in cigarettes are thought to cause cataracts - loss of lens clarity.

The researchers estimate that 400 cases of cataract surgery each year, or 13 per cent, are due to smoking.

In what is the first assessment of the effects of smoking on New Zealanders' eyesight, the researchers applied overseas findings and say their figures are probably an underestimate.

Health Ministry spokesman Matthew Allen said there had been calls for many conditions, including strokes, to be included in health warnings on tobacco packets.

Warnings introduced last year must be allowed to bed down before any new ones could be considered.

He said the ministry's priorities were the smokefree legislation now before Parliament and looking at the disclosure and controlling of constituents in tobacco.

Retina specialist Dr Dianne Sharp said the main factor associated with AMD was ageing, but in the last five years two large studies had shown that smoking increased the risk.

About 1000 New Zealanders a year developed AMD, she said.

A significant number lost their central vision solely because they smoked.

Dr Sharp doubted that those people would realise smoking was the cause.

"I don't think the public know about the link at all."

The condition meant people could not read, drive a car or watch television, and had difficulty getting around.

"It is not like total blackness ... but it is a severe visual impairment."

Ophthalmologist Dr Trevor Gray said AMD was the leading cause of blindness in Westernised countries.

He also believed there was little public awareness of the link with smoking.

About 40 other factors, including sunlight and diet, could contribute to AMD, he said.

Foundation for the Blind spokesman Chris Orr said 67 per cent of its clients were aged over 65.

About 20 years ago, a senior staff member decided to cancel an annual $25,000 donation of petrol vouchers from a large tobacco company.

Mr Orr said the staff member had suspected that smoking and blindness might be linked, and such sponsorship was inappropriate.

John Galligan, of industry group British American Tobacco NZ, said it was up to the Government to decide which health warnings were printed on cigarette packets.

His organisation would wait to see the research peer-reviewed.

"Because a report says one thing doesn't necessarily make it true. It just takes it up there for debate among the scientific community."

nzherald.co.nz/health