Increased Winter Mortality (Excess Winter Deaths)

The Increased Winter Mortality (Excess Winter Deaths) figure for Scotland in 2015/16 was 2,850.

Increased Winter Mortality or Excess Winter Deaths are recorded by the National Records of Scotland (NRS). 

There is no single cause of 'additional' deaths in winter. Very few are caused by hypothermia. Most are from respiratory and circulatory diseases such as pneumonia, coronary heart disease and stroke. In only a small proportion of deaths is influenza recorded as the underlying cause.

The seasonal increase in mortality in the winter has been defined as the difference between the number of deaths in the four 'winter' months (December to March) and the average of the numbers of deaths in the two four month periods which precede winter (August to November) and follow winter (April to July).

Statistics of the seasonal increase in mortality in the winter inform public debate and the development of government policy on matters such as the health of the elderly population, fuel poverty and whether there is a need to improve the housing stock in terms of central heating and thermal insulation.

A separate document, Increased Winter Mortality - Background Note, published in October 2010 (available on the NRS website), gives information about some of the medical causes of the seasonal increase in mortality in the winter, describes some research studies' findings on factors that influence it, reports on a comparison of the figures for a number of European countries, mentions previous publications on this topic, and provides references to the sources of the material.

The main points to note are:

  • high cold-related mortality is associated with low indoor temperatures, and with people not wearing appropriate clothing when outdoors in cold weather;
  • increased winter mortality was at the same level in Scotland as the overall mean for the 14 European countries covered by a comparative study; and
  • the seasonal increase in mortality in the winter is higher in countries with a warmer winter climate, probably because their homes tend to be poorly insulated and their populations tend not to dress well for cold weather.

Key documents:

The annual statistics are available here from the NRS. The increased winter mortality (Excess Winter Deaths) figure for Scotland in 2015/16 was 2,850.

The archive on increased winter mortality is available here.

The Occasional Paper (published in April 2002) on "The Raised Incidence of Winter Deaths" is here

Key facts:

  • There were 20,503 deaths registered in Scotland in the four months of winter 2015/16 (December to March), compared with 22,013 in winter 2014/15.
     
  • Comparing the number of deaths in the four winter months with the average for the two adjacent four-month periods, the seasonal increase in mortality in winter 2015/16 was 2,850.
     
  • The seasonal increase in mortality has been calculated for every winter from 1951/52. The figure of 2,850 for winter 2015/16 was 1,210 fewer than the corresponding value of 4,060 for the previous winter, which was the largest since 1999/2000 (when the seasonal increase was 5,190). The seasonal increase of 2,850 in winter 2015/16 was smaller than in most of the previous 64 winters, but exceeded the level seen in 14 of the previous 20 winters, and in 8 of the previous 10 winters.
     
  • The long-term trend in the seasonal increase in mortality in the winter has clearly been downward: although there have been unusually large figures in some years (including winter 2014/15), the height of the peaks has generally been falling. The 5-year moving average, which smoothes out much of the year to year fluctuation, has tended to decline and is now 2,386, which is its fourth lowest value ever. The previous two values (2,046 and 2,306) were lower. Before then, the 5-year moving average had not changed much since the early 2000s.
     
  • The latest 16 winters have had seven out of the ten lowest seasonal increases in mortality ever recorded. Over the 65 years covered by these statistics, the lowest seasonal increase in mortality was for winter 2011/12 (1,420), the second lowest was for winter 2013/14 (1,600), the third lowest was for winter 2005/06 (1,780), the fourth lowest was for winter 2001/02 (1,840), and the fifth lowest was for winter 2012/13 (2,000). The eighth and ninth lowest seasonal increases in mortality were for winter 2007/08 (2,180) and winter 2000/01 (2,220).