(i) to compare Helicobacter pylori serology in two 70-year-old cohorts in Gothenburg, Sweden, born 21 years apart, (ii) to study H. pylori serology in a 70-year-old cohort over 20 years.
H. pylori serology at the age of 70 was investigated in 98 men and 132 women born in 1901/02 and in 77 men and 113 women born in 1922. In 21 men and 40 women Helicobacter serology was monitored longitudinally with examinations at 70, 81, and 90 years of age. The analyses were performed on frozen samples by use of an in-house enzyme immunoassay with a sensitivity of 0.99, specificity of 1.00 and positive and negative predictive values of 0.96 and 1.00, respectively. Absorbance values or = 0.700 were interpreted as positive, and values in between as inconclusive.
The 70-year-old cohort, born in 1922, showed a significantly lower proportion of subjects with positive H. pylori serology in both men (57.1% vs 80.6%) and women (48.7% vs 75.8%) compared with 70-year-olds born in 1901/02. There were no significant sex differences in either cohort. No longitudinal increase or decrease could be demonstrated in those who were examined at 70, 81 and 90 years of age.
The difference in H. pylori prevalence between the two cohorts may reflect a rapid change in socio-economic conditions in Sweden during this 20-year period.