Thousands of disabled people are being forced to wait for NHS equipment which, when it does arrive, is often outdated, uncomfortable or unusable, according to a report published yesterday which has set off alarm bells in Downing Street.

The standards of NHS disability equipment services, which supply everything from hearing aids to prosthetic limbs and wheelchairs, were "unacceptably low" said the report by the Audit Commission, which supervises spending by local governments and health authorities.

Tony Blair, who will discuss the report with the commission today, said last night: "We cannot have a situation where older and disabled people are let down in the way this report suggests."

The Prime Minister said patients should be more involved in shaping services and that the Government was determined to end the wide variation of provision throughout the country.

Poor quality services in England and Wales are stripping disabled people of their dignity and independence, said Nick Mapstone, a project manager at the Audit Commission and author of the report.

"A lack of proper equipment ends up costing the NHS millions of pounds in residential care or hospital costs for people who could live on their own if the service was improved," he said.

Disability equipment services cost the NHS and local government a total of £400m a year. But the report found some local social services lose up to 80 per cent of their community equipment (such as bath mats, hoists and mattresses) because they don't keep proper records.

Of the 4 million registered disabled people in Britain who are supplied with NHS equipment, 2 million have hearing aids, 1 million have community equipment and 750,000 have wheelchairs.

The report also investigated the provision of artificial limbs for the 65,000 people who have had amputations and 400,000 users of orthopaedic footwear such as callipers.

It found that a fifth of health authorities had a six-month wait for the fitting of a hearing aid while the average wait was 19 weeks.

Even then, one in three NHS hearing aids are infrequently or never used because they are of poor quality and patients are not taught how they work. The hearing aids provided are based on 1970s technology rather than the new, digital aids which work much better.

One in four people who have an artificial limb provided by the NHS do not use it as often as they want to because of poor fitting which causes discomfort and pain.

A fifth of amputees wait more than six months before they have a first appointment for fitting their artificial limb. Experts say amputees should be seen and fitted for a prosthetic as soon as their stumps have healed.