1 Introduction

Employing around 5,000 people in the UK, the tobacco industry generated over £950 million in revenue for the exchequer in the year 2000. Each year the treatment of smoking related illnesses costs the NHS £1.7 billion, and accounts for 284,000 hospital admissions, which occupy an average of 9,500 hospital beds every day.1, 5
   Government targets aim to reduce smoking prevalence to 26% by 2005 and to 24% by 2010. The development of cessation intervention services represents a cost effective approach to managing the health costs of smoking and these are estimated to be 34 to 140 times more cost effective (between £212 and £873 per year life gained)3, 6 compared to the benchmark of £30,000 per quality adjusted life year, for acceptable expenditure in the NHS, as set by the National Institute for Clinical Effectiveness (NICE).

2 Prevalence of tobacco smoking

Since 1974 the proportion of adult smokers within the UK population has declined from 51% of men and 41% of women to a current level of 28% of men and 26% of women (approximately 12 million adults).1 In the South West 27% of adults (approximately 1.1 million people) smoke tobacco. The highest rates2 are currently associated with the western part of the region with South and West Devon, Cornwall and North and East Devon recording values of 33%, 31% and 30% respectively. Rates in Wiltshire, Avon and Somerset range from 29% and 27% whilst Gloucestershire and Dorset exhibit the lowest rates (25%). These, however, mask significant variations in smoking prevalence rates at smaller geographical areas. For example, it is known that nationally rates are significantly correlated with deprivation and are generally higher in urban than rural areas.
   A major obstacle to studying the relationship between smoking and disease is the lack of both current and historical smoking prevalence data at areas below old health authority boundaries. Despite this lack of historical data on smoking it is possible to estimate the proportion of deaths from lung cancer and vascular disease attributable to smoking and from this to estimate the absolute numbers.

3 Premature mortality from lung cancer and vascular disease attributable to tobacco smoking

Age standardised estimates for premature mortality in males and females aged 35–69 are presented by Primary Care Trust (PCT) for the South West. Estimates are derived using the methodology of Peto et al 1992. The methodology assumes that current lung cancer mortality provides a better measure of the impacts of lifetime tobacco smoking than does current smoking prevalence.

   Age standardised figures for the proportion and numbers of deaths attributable to tobacco smoking are presented by PCT and gender in Figures 1 and 2 (lung cancer) and Figures 3 and 4 (vascular disease). Tables showing the numeric values as well as average annual rates of tobacco attributable deaths from lung cancer are shown in Appendix 1 (males) and Appendix 2 (females).
   Figure 1 shows that the proportion of premature deaths from lung cancer attributable to tobacco smoking is higher in men compared to women, and in three PCTs, (Bristol South and West, Plymouth and Bristol North) exceeds 90%. The largest proportion of premature deaths in women is associated with Bristol North, Bristol South and West and Swindon PCTs (81%, 80% and 79% respectively).

   The highest number of deaths for the period 1999–2001 (Figure 2) from lung cancer in men is associated with Plymouth PCT (104), Bristol North PCT (74) and Bristol South and West PCT (67). The highest values for women (36 and 35) are associated with Bristol North and Plymouth PCTs respectively.
   Mid Devon PCT, South Hams and West Devon PCT and East Devon PCT exhibit the lowest proportions of premature deaths for both men and women ( Figure 1 ).

   Figure 3 shows that over 20% of the premature deaths in men from vascular disease can be attributed to tobacco smoking in three PCTs, (Bristol South and West, Plymouth and Bristol North). The largest proportion of deaths in women is associated with Swindon PCT. At 30%, the value for Swindon is almost double the next highest value (15.4%) that is associated with Bristol North PCT. Three other PCTs (Bristol South and West, West of Cornwall and North and East Cornwall) record values greater than 12%.

   West Devon (5%), Cotswold and Vale (9.6%) and Mid Devon (10.4%) PCTs have the lowest percentage of deaths from vascular disease in men, the lowest for women being associated with Mid Devon, East Devon and South Somerset PCTs (2.9%, 4.8% and 5.3% respectively). In three PCTs (Swindon, West of Cornwall and South Hams and West Devon) the proportion of deaths from vascular disease was higher in women compared to men.

   The highest number of premature deaths in men from vascular disease (88) is in Plymouth PCT ( Figure 4 ). Three other PCTs (Bristol North, Bristol South and West and West Gloucestershire) are associated with over 40 deaths between 1999 and 2001. Swindon (32), Bristol North (19) and West of Cornwall (15) PCTs recorded the highest numbers of deaths in women.

   The distribution of the proportion of deaths for both men and women is presented by quartile in Figure 5 (lung cancer) and Figure 6 (vascular disease). Four PCTs (Bournemouth, Bristol North, Plymouth and Bristol South and West) fall in to the worst quartile (highest) for smoking attributable deaths from lung cancer and vascular disease. East Devon, Mendip, Mid Devon, South Hams and West Devon and South Wiltshire PCTs fall in to the lowest (best) quartile in terms of premature mortality from lung and vascular disease. PCTs associated with a lower quartile for lung cancer compared to vascular disease include Bath and North East Somerset (BANES), Kennett and North Wiltshire, North and East Cornwall, North Somerset, Torbay and West of Cornwall. PCTs associated with a higher proportion of lung cancer mortality compared to vascular disease include Central Cornwall, Cheltenham and Tewkesbury, Poole, Somerset Coast and South West Dorset.

4 Discussion

  Our Healthier Nation (OHN) identified targets for reducing deaths from vascular disease and cancer. They are :

  'To reduce the death rate from coronary heart disease and stroke and related diseases in people under 75 years by at least two-fifths by 2010'
'To reduce death rate from cancer in people aged under 75 by at least one-fifth by 2010'

  The data presented in this Bulletin are a useful tool in monitoring progress against the OHN targets.

  Smoking is the most important avoidable risk factor for premature death in people under 70. Cancer and vascular disease account for the majority of premature deaths. Up to 90% of lung cancer may be caused by cigarette smoking. This contrasts with vascular disease where up to a quarter of premature deaths are usually considered to be attributed to smoking. In vascular disease, other factors for example diet, physical activity, obesity, cholesterol and presence of diabetes also play a significant role in causation. In absolute numbers terms when all ages are taken into consideration, smoking accounts for more deaths from vascular disease than from lung cancer.

  The data shown in this Bulletin confirm the marked male/female differences in premature mortality for lung cancer and vascular disease which reflect previous smoking prevalence rates. However, these data are just a snap shot in time. If trends for incidence and mortality from lung cancer (all ages) are looked at ( Figure 7 ), they show rapidly decreasing rates for males contrasting with much slower reductions for females. Indeed, the incidence of lung cancer in females has risen so that it is now the second commonest cancer. As expected, inner city areas have higher premature rates of mortality from lung cancer and vascular disease and higher rates attributable to smoking reflecting past smoking prevalence rates.

  The age range 35 to 69 has been selected because the methodology used is thought not to be as stable in populations over the age of 70.
From a public health perspective, however, this significantly underestimates the true magnitude of the problem. Using lung cancer as an example, the percentage of cases over the age of 70 vary by PCT from 54% in Mendip to 78% in South Wiltshire for women and 57% in Swindon to 73% in East Devon for males. This may be even more so for men because of the significant reduction in smoking prevalence over the past three decades. People who are over 70 now would have been middle aged thirty years ago at a time when smoking prevalence rates in men reached over 50%.

  If the proportion of cases attributable to smoking from this study is applied to the total deaths from lung cancer the total number of attributable deaths over 3 years for the region is 4,648 for males and 1,833 for females. For comparison with the data shown in Appendix 1 , the total number of smoking attributable lung cancer deaths in males over a 3 year period is for Bristol South and West 200 (c.f. 67 aged 35–69), for Plymouth 278 (c.f. 104), for Mid Devon 68 (c.f. 14) and for South Hams & West Devon 98 (c.f. 17). For females for Bristol North the total smoking attributable lung cancer deaths over 3 years is 86 (c.f. 36 aged 35–69), for Bristol South & West 77 (c.f. 27), South Hams & West Devon 40 (c.f. 4) and East Devon is 53 (c.f. 9).

  These data raise a number of interesting issues. Further work will be undertaken to look at the maturity of the smoking epidemic in relation to PCT population cohorts across the region. This will examine temporal and spatial variation in smoking attributable disease. The impact of income deprivation attributable to smoking disease will also be examined.


 

References

1. ASH Fact sheet No2. Smoking Statistics: Illness and Death

2. Health Survey for England 1999; Office of National Statistics

3. Smoking Kills– a White Paper on Tobacco Department of Health, The Stationery Office. 1998.

4. Shinton R and Beevers G. Meta analysis of relation between cigarette smoking and stroke. BMJ 1989; 298 789–94

5. The UK smoking epidemic: deaths in 1995. Health Education Authority. 1998.

6. Peto R, Lopez AD, Boreham J, Thun M, Heath C Jr. Mortality from smoking in developed countries: indirect estimation from national vital statistics. Lancet 1992;339:1268–78.

Acknowledgements

We would like to express our thanks to the Directors of Public Health who commented on earlier drafts of this report, especially Dr Chris. Hine, and also to Professor Peto and his team who have validated our use of their methodology.

Appendix 1