Abstract

The prevalence of use of peptic ulcer drugs in the Danish population is described at two points in time using registrations of applications for reimbursement. In 1977-81, the prevalence of use of cimetidine was 0.4% in men and 0.2% in women. In 1989-90, the prevalence of use of peptic ulcer drugs was 1.3% in men and 1.2% in women. The increase in prevalence was apparent in all age groups, but most pronounced at relatively old age. The median age of users increased from 55 years in 1977-81 to 63 years in 1989-90. The data indicated that a third of those who used peptic ulcer drugs in 1977-81 also used these drugs in 1989-90, conditional on surviving this period. The probability of becoming a long term user was highest for those who were 50-69 years in 1977-81. The incidence of gastric cancer was investigated in the cohort of persons who used cimetidine in 1977-81. An excess risk of gastric cancer was apparent in the first years after start of cimetidine use. This is thought to reflect a selection bias. Significantly increased incidence was also observed in women seven years or longer after start of cimetidine use (RR = 4.7; 95% CI: 1.7-10.3). This estimate was, however, based on only six cases, and a similar pattern was not observed in men.