J Boreham

Estimates are made of the numbers and proportions of deaths attributable to smoking in 44 developed countries in 1990. In developed countries as a whole, tobacco was responsible for 24% of all male deaths and 7% of all female deaths, rising to over 40% in men in some former socialist economies and 17% in women in the USA. The average loss of life for all cigarette smokers was about 8 years and for those whose deaths were attributable to tobacco about 16 years. Trends in mortality attributable to tobacco differed between countries. In some the mortality in middle age (35-69 years) had decreased by half in men since 1965; in others it was continuing to increase. In women, the proportion was mostly increasing, almost universally in old age. Mortality not attributable to smoking decreased since 1955 in all OECD (Organization for European Collaboration and Development) countries, by up to 60% in men and more in women. No precise estimate can be made of the number of deaths attributable to smoking in undeveloped countries, but the prevalence of smoking suggests that it will be large. In the world as a whole, some 3 million deaths a year are estimated to be attributable to smoking, rising to 10 million a year in 30-40 years' time.

OBJECTIVE: To assess the hazards at an early phase of the growing epidemic of deaths from tobacco in China. DESIGN: Smoking habits before 1980 (obtained from family or other informants) of 0.7 million adults who had died of neoplastic, respiratory, or vascular causes were compared with those of a reference group of 0.2 million who had died of other causes. SETTING: 24 urban and 74 rural areas of China. SUBJECTS: One million people who had died during 1986-8 and whose families could be interviewed. MAIN OUTCOME MEASURES: Tobacco attributable mortality in middle or old age from neoplastic, respiratory, or vascular disease. RESULTS: Among male smokers aged 35-69 there was a 51% (SE 2) excess of neoplastic deaths, a 31% (2) excess of respiratory deaths, and a 15% (2) excess of vascular deaths. All three excesses were significant (P<0.0001). Among male smokers aged >/70 there was a 39% (3) excess of neoplastic deaths, a 54% (2) excess of respiratory deaths, and a 6% (2) excess of vascular deaths. Fewer women smoked, but those who did had tobacco attributable risks of lung cancer and respiratory disease about the same as men. For both sexes, the lung cancer rates at ages 35-69 were about three times as great in smokers as in non-smokers, but because the rates among non-smokers in different parts of China varied widely the absolute excesses of lung cancer in smokers also varied. Of all deaths attributed to tobacco, 45% were due to chronic obstructive pulmonary disease and 15% to lung cancer; oesophageal cancer, stomach cancer, liver cancer, tuberculosis, stroke, and ischaemic heart disease each caused 5-8%. Tobacco caused about 0.6 million Chinese deaths in 1990 (0.5 million men). This will rise to 0.8 million in 2000 (0.4 million at ages 35-69) or to more if the tobacco attributed fractions increase. CONCLUSIONS: At current age specific death rates in smokers and non-smokers one in four smokers would be killed by tobacco, but as the epidemic grows this proportion will roughly double. If current smoking uptake rates persist in China (where about two thirds of men but few women become smokers) tobacco will kill about 100 million of the 0.3 billion males now aged 0-29, with half these deaths in middle age and half in old age.

Objective To compare the effect on the course of advanced prostate cancer of hormone treatment commenced on diagnosis with that deferred until clinically significant progression occurs. Patients and methods Nine hundred and thirty-eight patients with locally advanced or asymptomatic metastatic prostate cancer were randomized either to immediate treatment (orchidectomy or luteinizing hormone-releasing hormone analogue) or to the same treatment deferred until an indication occurred, Follow-up and management were otherwise according to the participating clinician's normal practice. Information was collected annually on survival, local and distant progression, and major complications (pathological fracture, spinal cord compression, ureteric obstruction and extra-skeletal metastases). Results Follow-up data were returned on 934 patients; 51 deferred patients died from causes other than prostate cancer before treatment was started (but only five of these presented at age <70 years) and 29 died from prostate cancer before treatment could be started, Treatment was commenced for local progression almost as frequently as for metastatic disease, Progression from M0 to M1 disease (P<0.001, two-tailed) and development of metastatic pain occurred more rapidly in deferred patients; 141 deferred patients needed transurethral resection for local progression compared with 65 treated immediately (P<0.001, two-tailed). Pathological fracture, spinal cord compression, ureteric obstruction and development of extra-skeletal metastases were twice as common in deferred patients. Of the patients who died, 67% did so from prostate cancer; 361 patients died in the deferred arm compared with 328 in the immediate arm (P=0.02, two-tailed), where 257 and 203 were deaths from prostate cancer, respectively (P=0.001 two-tailed). This difference was seen largely in M0 patients, with 119 and 81 deaths from prostate cancer, respectively (P<0.001 two-tailed). Conclusions The results consistently favour immediate treatment, although some of the data, especially on M0 patients, are immature. The implications for management of advanced prostate cancer are discussed.

A total of 34,439 male British doctors, who reported their smoking habits in November 1951, were followed, with periodic up date of changes in their habits, until death, emigration, censoring. or November 2001. Information was obtained about their mortality from 28 of the 30 types of cancer in men reviewed by the International Agency for Research on Cancer (no death was recorded from the other two). In all, 11 of the 13 types in men that the Agency classed as liable to be caused by smoking were significantly related to smoking and the findings for the other two, which caused only few deaths, suggested they might be. Of the 13 types in men for which the Agency found only sparse or inconsistent data and for which we had data, only two appeared to be possibly related (one positively, one negatively), and the 638 deaths for the summed group were clearly unrelated to smoking. Of the two types for which the Agency thought that the relationship with smoking might be due to bias or confounding, the findings for one (prostate cancer) tended to support the belief that smoking was unrelated, and those for the other (colorectal cancer) showed a weak relationship with smoking, which (in a small subset) could not be attributed to confounding with the consumption of alcohol.