[Prevalence of Helicobacter pylori infection in primary health care]

Antibody reactivity against Helicobacter pylori proteins in a sample of the Spanish adult population in 2008-2013

BACKGROUND

Differences in Helicobacter pylori protein expression have been related to the risk of severe gastric diseases. In Spain, a marked geographic pattern in gastric cancer mortality has long been reported.

OBJECTIVE

To characterize antibody reactivity patterns against 16 H. pylori proteins, by age, sex, and region of birth, in a large sample of the Spanish adult population.

MATERIALS AND METHODS

Antibody reactivity was quantified by H. pylori multiplex serology in a sample from the control group of the multicase-control study MCC-Spain. For this analysis, 2555 population-based controls were included. Each participant was classified as seropositive or seronegative for each protein according to specific cutoffs. Overall H. pylori seroprevalence was defined as positivity against ≥4 proteins. Descriptive analyses by age, sex, and region of birth were performed for both seroprevalence and seroreactivity (continuous measure). Differences among groups were tested by logistic and linear regression models.

RESULTS

Overall H. pylori seroprevalence increased with age in both sexes. For ages 55-74, seroprevalence was lower in women than in men (84% vs 92%, P<.001). Region of birth explained 7% of the variability in seroprevalence. Among H. pylori seropositive subjects, proteins with the highest seroprevalence were GroEL, NapA, HP231, and Omp. Seropositivity for most of the proteins increased or remained stable with age, rising mainly for CagA, GroEL, and HyuA in women. A clear cohort effect was not observed.

CONCLUSIONS

This is the first study to describe the antibody patterns against 16 H. pylori proteins in the Spanish population. We found variability in the H. pylori antibody profiles according to both individual factors such as age and sex, and environmental factors such as the region of birth. The slightness of the reduction in seropositivity with decreasing age highlights the ongoing importance of this infection.

[Prevalence of Helicobacter pylori infection in primary care: sero-epidemiological study]

OBJECTIVES

To find the prevalence of Helicobacter pylori (HP) infection in primary care in our area and to study factors associated with this infection.

DESIGN

Descriptive and prospective study.Setting. Urban health district with 30 765 people registered.

PARTICIPANTS

267 patients, selected by quota sampling from the census of age and sex groups, as a function of an alpha of 0.05, 0.06 accuracy, and expected prevalence of 50%.

MAIN MEASUREMENTS

HP infection was studied through validated IgG serology (ELISA Wampole(R)). The following were studied as associated factors: age, sex, education, profession, alcohol and tobacco consumption, and non-steroidal anti-inflammatory drugs taken.

RESULTS

Mean age was 38.4, and 51.3% were women. Prevalence of HP infection was 52.4% (95% CI, 46.4-58.4). This proportion increased steadily with age, with a minimum of 11.5% in the 0-9 years-old range and a maximum of 87.5% in the 60-69 years-old group. There was more HP in men (56.9%) than in women (48.2%). In univariate analysis a linear tendency was found between HP infection and increased age (P<.0001) and the consumption of alcohol (P=.003), with no relationship to other variables studied. In the multivariate analysis, only age maintained statistical significance (P=.001).

CONCLUSIONS

In our area the prevalence of HP infection is similar to that in other studies: it increases steadily with age and shows en epidemiological pattern that is half-way between countries of high and low prevalence.