Author: Dr Tony Williams, Consultant Occupational Physician, Working Fit Ltd.
Date: December 2012.
The following information was prepared for a study into fire-fighter pension age, in order to determine whether there was a likelihood of significantly increased mortality in service if the pension age was increased..
The simplest indication of the impact of chronic disease is mortality rate. The impact of the disease will be substantial well before death, but statistics on morbidity are not available for most conditions, so mortality statistics are an important indicator of the increase in the impact of chronic disease with age. The following table includes mortality rates for the most common chronic diseases likely to impact on firefighters.
Death rates per thousand population in England and Wales in 2010, age-adjusted
All diseases of circulatory system
Ischaemic heart disease
Morbidity and mortality rates are usually expressed in ten year age bands. The median value will not be central because of the increase with age, so a graphical representation of the increase needs to assume a shift to the right of the median age for the group. Thus a mortality rate for ischaemic heart disease for 55-64 year old men is 1.6 per thousand per annum. This does not mean that the rate for 60 year olds is 1.6. The rates for the ten year age bands either side would suggest an approximate age of 62 for this rate to be reached. Rates are usually, as in this case, age-adjusted to reflect the rates against the total population at each age.
These death rates are illustrated graphically below to demonstrate the rate of rise.
Death rates per thousand, males, England and Wales 2010
Death rates per million, females, England and Wales, 2010
Around 80 % of mortality in the age range 45-54, and above, results from circulatory disease, neoplasms and respiratory disease. These are likely to be the main causes of morbidity affecting firefighter fitness and ill health retirement, and will be considered in more detail below.
Several older studies (pre-1990) have shown increased mortality from various chronic diseases among firefighters compared to the general population, but often with very wide confidence intervals (Sardinas et al., 1986, Musk et al., 1978). New research has shown the opposite, the new research is based on larger studies and has been confirmed by actuarial studies of UK firefighters. Firefighters are expected to be reasonably fit, so a significant healthy worker effect could be expected. A recent study, among firefighters in Hamburg, Germany, showed a significant healthy worker effect with an overall standardised mortality ratio (SMR) of 0.79 (95 % CI, 0.74-0.84) (Wagner et al., 2006). This would suggest that figures for the general population should be adjusted down by this amount. A review by the Government Actuary’s Department in 2007 confirmed this, showing that men firefighters lived between one and two years longer than the average UK population, while women firefighters lived nearly a year longer (Government Actuary's Department, 2007). Trends in ill-health retirement suggested that this should increase to a longevity of plus three years. The difference increased with increased age at retirement, suggesting that working longer as a firefighter increased longevity. A study of hazardous occupations found that firefighting was 23rd out of 30 (Roberts, 2002) and this was attributed to considerable investment and effort put into health and safety by fire authorities in consultation with the Health and Safety Executive (Bain et al., 2002). A healthy worker effect adjustment down by 20 % will therefore be used in this study in relation to chronic disease morbidity and mortality.
For men in England and Wales, the mortality data indicate a mortality of 3.2 per thousand per annum at age 50, and a mortality of 8.3 per thousand per annum at age 60, suggesting a mortality at age 50-54 of around 4 per thousand per annum and at age 55-59 of around 7 per thousand per annum. This suggests an increase of around 75 % for the age group 55-59 compared to 50-54, and applying a healthy worker adjustment the expected mortality from all causes would be 5.6 per thousand per annum for ages 55-59.
For women in England and Wales, the mortality data indicate a mortality of 2.1 per thousand per annum at age 50, and a mortality of 5.3 per thousand per annum at age 60, suggesting a mortality at age 50-54 of around 2.7 per thousand per annum and at age 55-59 of around 4 per thousand per annum. This suggests an increase of around 50% for the age group 55-59 compared to 50-54, and applying a healthy worker adjustment the expected mortality from all causes would be 3.2 per thousand per annum for ages 55-59.
BAIN, G., LYONS, M. & YOUNG, A. 2002. The future of the Fire Service: reducing risk, saving lives. London.
GOVERNMENT ACTUARY'S DEPARTMENT 2007. Actuarial valuation of the Firefighter's Pension Schemes as at 31 March 2007. In: DEPARTMENT, G. A. S. (ed.). London.
MUSK, A. W., MONSON, R. R., PETERS, J. M. & PETERS, R. K. 1978. Mortality among Boston firefighters, 1915--1975. Br J Ind Med, 35, 104-8.
ROBERTS, S. E. 2002. Hazardous occupations in Great Britain. Lancet, 360, 543-4.
SARDINAS, A., MILLER, J. W. & HANSEN, H. 1986. Ischemic heart disease mortality of firemen and policemen. Am J Public Health, 76, 1140-1.
WAGNER, N. L., BERGER, J., FLESCH-JANYS, D., KOCH, P., KCHEL, A., PESCHKE, M. & OSSENBACH, T. 2006. Mortality and life expectancy of professional fire fighters in Hamburg, Germany: a cohort study 1950 2000. Environ Health, 5, 27.