Global burden of disease due to smokeless tobacco consumption in adults : analysis of data from 113 countries

BACKGROUND: Smokeless tobacco is consumed in most countries in the world. In view of its widespread use and increasing awareness of the associated risks, there is a need for a detailed assessment of its impact on health. We present the first global estimates of the burden of disease due to consumption of smokeless tobacco by adults. METHODS: The burden attributable to smokeless tobacco use in adults was estimated as a proportion of the disability-adjusted life-years (DALYs) lost and deaths reported in the 2010 Global Burden of Disease study. We used the comparative risk assessment method, which evaluates changes in population health that result from modifying a population's exposure to a risk factor. Population exposure was extrapolated from country-specific prevalence of smokeless tobacco consumption, and changes in population health were estimated using disease-specific risk estimates (relative risks/odds ratios) associated with it. Country-specific prevalence estimates were obtained through systematically searching for all relevant studies. Disease-specific risks were estimated by conducting systematic reviews and meta-analyses based on epidemiological studies. RESULTS: We found adult smokeless tobacco consumption figures for 115 countries and estimated burden of disease figures for 113 of these countries. Our estimates indicate that in 2010, smokeless tobacco use led to 1.7 million DALYs lost and 62,283 deaths due to cancers of mouth, pharynx and oesophagus and, based on data from the benchmark 52 country INTERHEART study, 4.7 million DALYs lost and 204,309 deaths from ischaemic heart disease. Over 85 % of this burden was in South-East Asia. CONCLUSIONS: Smokeless tobacco results in considerable, potentially preventable, global morbidity and mortality from cancer; estimates in relation to ischaemic heart disease need to be interpreted with more caution, but nonetheless suggest that the likely burden of disease is also substantial. The World Health Organization needs to consider incorporating regulation of smokeless tobacco into its Framework Convention for Tobacco Control

The distribution of cancer within the large bowel

The distribution of cancer of the anatomical sub-sites of the colon and rectum in Alameda County (California), Bombay, Denmark, Kingston and St Andrew (Jamaica), Miyagi Prefecture (Japan), New Zealand, Norway, Puerto Rico, Saskatchewan (Canada). Singapore, The South Metropolitan Cancer Registry (SMCR) (England), and Sweden were analysed. In this series, the highest rates for large-bowel cancer are found in North America and New Zealand; the lowest in the East (Japan, Bombay and Singapore) and the Caribbean, while intermediate rates prevail in Scandinavia and England. The pattern of sub-site distribution of the cancers throughout the large bowel is similar in areas of high and intermediate risk; namely, there is a decreasing incidence from ascending colon towards the descending colon with a sharp increase in incidence at the sigmoid colon, the rates for rectum being in turn higher than those for the sigmoid. In low-incidence areas, the general pattern is the same, but there may be a deficit of sigmoid cancers. This remains to be proved. Denmark shows a significant excess of lower rectum cancer, particularly in males. The age-standardized incidence rates for rectum cancer in this registry are higher than in any of the others, although the rates for other parts of the large intestine in Denmark are in the intermediate range. This finding should be exploited. With advancing age, the sex ratio for colon cancer as a whole shows a higher male risk; this male excess is, however, confined to the descending and sigmoid colon. The sex ratios for ascending and transverse colon cancer do not change with advancing age, while those for the sigmoid, and to a lesser extent the descending colon, do. Rectal cancer is commoner in males, the male preponderance becoming more pronounced after 65 years of age. For descending, sigmoid and rectal cancers, incidence increases more steeply with age in males than in females, the incidence-age curves on a log-log scale tending to have a downward curvature for the older age-groups. The slopes for ascending and transverse colon cancer do not differ between the sexes and their age-incidence curves have an upward curvature, particularly in women. It makes little difference to the incidence rates whether cancers of the recto-sigmoid are included in the rectum or the colon. The findings are discussed in the light of current aetiological theories. The results are consistent with the sub-site risk being related to the rate of transportation of colonic content. Transportation rates in the variety of risk situations need to be investigated, with particular attention being paid to the sigmoid in low-risk areas

The economic impact of the information sector in Singapore

10.1007/BF00418970Economics of Planning23151-7