Every year around this time, as the weather turns a little colder running up to Christmas, the "Reach Out - Be a Good Neighbour" campaign gets under way. This year, as you may have noticed in your Irish Times a day or two ago, it was introduced by Dr Shiela McEvilly of the Eastern Health Board.
The campaign is organised by a band of dedicated volunteers, and its aim is to make the public more aware of the needs of elderly or reclusive neighbours who may live alone and who may be vulnerable to crime, fire, cold or other dangers.
Low temperatures provide a very definite threat to those who live alone. The expense of proper heating, or insufficient insulation in a dwelling, may result in a temperature drop sufficient to be fatal.
We humans are warm-blooded animals whose survival depends critically on our ability to keep our core body temperature very close to its design value of about 37 C.
If cold conditions cause a drop in the internal body temperature of more than 2 C, the normal biochemical reactions which keep us all alive become impossible; a condition known as hypothermia sets in, and any further loss of body heat results in coma and ultimately death.
But hypothermia is not the only cause of death from cold. Low temperatures result in an increased susceptibility to strokes in older people, because, if my understanding of the explanation is correct, the blood courses less freely through the veins and becomes more liable to clots.
In addition, some people also react to unpleasantly low temperatures by producing stress hormones, which then suppress the immune responses of the body and leave it with reduced resistance to possible respiratory infection, which then takes its toll in its own individual way.
Ireland, according to Dr McEvilly, experiences a 24 per cent increase in deaths of older people during the winter months compared to summer, a figure which, apparently, is one of the highest in Europe. And she went on to relate the interesting results of recent research into these matters.
It seems that the rate of increase in the number of deaths with falling temperature is higher in warmer regions of Europe than in the colder countries; to put it another way, more people die, pro rata, during a cold snap in Athens than during a cold snap in Helsinki.
The obvious reason is that people in the colder regions are more used to cold. They wrap up more effectively when out of doors, have better insulated houses and do not try to economise on heat.