Observations on the effect of abolishing analgesic abuse and reducing smoking on cancers of the kidney and bladder in New South Wales, Australia, 1972-1995

Abstract

OBJECTIVES: We have assessed the effect on the rates of cancers of the kidney and bladder of measures undertaken by the government in 1979-1983 to limit smoking and analgesic abuse in New South Wales (NSW). Sale of phenacetin-containing analgesics, previously available without restriction and regularly taken by 11-13% of women and 4-9% of men in NSW, was prohibited from 1979. The prevalence of current smokers among adult Australian men had fallen from 72% in 1945 to 43% in 1980 and to 28% in 1992. In women the corresponding figures were 26%, 31% and 24%. METHODS: Incidence and mortality data from the New South Wales Central Cancer Registry for the period 1972 to 1995 were analyzed, by sex and age, for trends over time. Relative survival was calculated for cases diagnosed in the period 1980-94 and followed until the end of 1996. RESULTS: Significant trends evident from these data were: throughout the period of review a rising incidence of, and to a lesser extent mortality from, renal parenchymal cancer for which relative survival has steadily improved; falling mortality from bladder cancer throughout the period of review, but more rapid after 1985; a reversal of the earlier increasing incidence of, and mortality from, cancer of the renal pelvis; and relative survival for bladder and renal pelvic cancers which was worse in women than men. Changes in registration practice in 1985 and 1993 introduced artifacts into the trends in incidence of bladder cancer. CONCLUSIONS: Improvements in the trends of incidence and mortality of cancers of the renal pelvis and bladder in the mid-1980s are interpreted, in the light of registration and clinical practice, to indicate a beneficial effect of regulations which virtually abolished analgesic abuse and, less certainly, a contribution from measures restricting smoking, in New South Wales. However, renal parenchymal cancer continues to increase, although there has been some apparent benefit of earlier detection