The mysterious reappearance of canoeist John Darwin after vanishing five years ago has cast the spotlight on a little-covered phenomenon: middle-aged men who go missing.

Bernard Cook is still receiving post.

But he has not passed over the threshold of his home and reached down to pick it up since 16 November 2005.

Some time around the middle of that day Mr Cook, estates director for the Mersey Docks and Harbour Company and due at an important meeting, took a van from his work and disappeared.

In the two years and 18 days that have passed there has only been one sighting, at a church in Coventry, that has given his family any hope.

It would be understandable to fear he had killed himself, but despite extensive police efforts no body has been found. He has not tried to access his bank accounts and there was no evidence of preparations for disappearance.

When we think of missing people we tend to assume vulnerable women, troubled teenagers and children running away. But there is a category of missing person that receives less coverage in the national news: men over the age of 30.

Across the UK, there are as many as 210,000 missing persons reports every year, although one person might be counted several times for numerous disappearances.

Media coverage

A 2004 random sample of 1,000 missing cases in London found that more than three-quarters were resolved within 48 hours, while 99% were resolved within a year.

The figures suggest that while the teenage missing are more likely to be girls, of all those over the age of 24 who disappear, 73% are male. Of those missing for more than a year, the longer they are missing the more likely they are to be older men.

Missing People, formerly the National Missing Persons Helpline (NMPH), works to get these men the same attention as others who have disappeared and whose cases are more readily picked up by the media.