Hospitals located in safe parliamentary seats where political competition is weak are much more likely to be closed than those in marginal constituencies, new research reveals.

The study, by academics at the London School of Economics, illustrates just how damaging shutting hospitals can be, with the authorities seemingly shying away from closures in politically sensitive areas. The report also reveals how much of a difference good management can make to the way in which hospitals operate. It finds that:

■ A slight improvement in the way in which a hospital is managed can result in up to 400 fewer deaths each year.

■ Hospitals are best managed when doctors and nurses are employed in senior management positions.

■ Those that perform best are in areas with a higher number of hospitals nearby, increasing competition.

Professor John Van Reenen, director of the Centre for Economic Performance at the LSE and co-author of the report, said he wanted to find out why hospital performance varied so much around the country. The academic said the study, which looked at 100 English hospitals and will be published this week in the journal Centrepiece, found that patients taken to well-managed hospitals after a heart attack were significantly more likely to survive.

He said it made sense that hospitals did well when people with clinical experience were in charge, because they could communicate in a language that "doctors and nurses understand".

In terms of closures, he added: "We found that in marginal constituencies hospitals are much less likely to be closed down. So there are far more hospitals in politically marginal wards." The reason, he added, was because health was the top priority for most people. "It is what people care about. What people really want to know is whether they will be looked after if they become unwell, and whether their relatives will be cared for."

He highlighted the case of Richard Taylor, a doctor whose campaign to keep Kidderminster hospital open resulted in him unseating a Labour minister in Wyre Forest in 2001. He then held on to the seat in 2005.

Taylor said there was always a "political element" when NHS services were reconfigured and decisions were made around units closing down. But he argued the key issue was whether there were alternative medical services nearby.

The MP refuted the notion that more competition improved hospital performance and said he was ardently against the market. "Since the instigation of the internal market in the NHS, and the purchaser-provider split and thus of competition, the numbers of management personnel have gone up sharply, sometimes by as much as tenfold."

Dr John Lister of Health Emergency, which campaigns against private-sector involvement in the NHS, agreed, arguing that co-operation rather than competition led to better health outcomes. "Under competition a few strong hospitals do better than others, but how do you then raise the standards of the others?"

David Furness, head of strategic development at the Social Market Foundation, said that the NHS was about far more than just hospitals and that protecting health services should be about "values not buildings".

"We need fewer hospital beds. People are treated more rapidly than ever before," he said. "But fewer beds mean fewer hospitals. And politicians will not accept the inevitable political pain of hospital closures. With the crisis in public finances threatening the future of the health service, this fixation with protecting hospitals from closure might tip the NHS over the edge."

Far be it from me to say this is another reason NOT to vote Labour (-: