Validity of an epidemiologic instrument for H. pylori screening among dyspeptic patients.
OBJECTIVE
To validate an epidemiological score for identifying dyspeptic patients at high risk of being H. pylori positive.


METHODS
Cross-sectional study including 434 users of primary health care units in the city of Pelotas, Southern Brazil, aged 18-45 years, and with symptoms of non-investigated dyspepsia, between 2006 and 2007. Dyspepsia was diagnosed according to Roma-II. The gold standard for H. pylori infection was the (13)C-urea-breath-test. The association between presence of H. pylori and independent variables was assessed through Logistic Regression. The score was built based on adjusted odds ratios. Sensitivity, specificity, and predictive values of different cutoffs were calculated.


RESULTS
Prevalence of H. pylori dyspeptic subjects was 74% (95% CI: 69;77.7). Prevalence was directly associated with age and number of siblings during childhood, and inversely associated with schooling; these variables were used in the construction of the score. The score ranged from 3 to 9 points. Scores 7, 8, and 9 had sensitivity of 36.6%, 22.3%, and 11.1%, and positive predictive values of 87.8%, 90.9%, and 92.1%, respectively. Without the score, 3 in every 4 dyspeptic patients would have received H. pylori erradication therapy. This proportion would have been lower with the score (one in three, six, and 11, for the cutoff points betwewen 7 and 9, respectively), albeit at the expense of a high rate of false-negatives.


CONCLUSIONS
The score was not valid for selectively identifying dyspeptic individuals candidate to eradication therapy for H. pylori. Contrary to the recommendation in developed countries, the test-and-treat strategy seems inappropriate for use in developing settings due to the high prevalence of H. pylori infection.
Santos
Iná Silva
IS
Universidade Federal de Pelotas, Pelotas, RS, Brasil.
Sassi
Raúl A Mendoza
RA
Minten
Gicele Costa
GC
Tuerlinckx
Giovana Costa
GC
Valle
Neiva C J
NC
Oliveira
Sandro S de
SS
Boccio
Jose
J
Barrado
Domingo Andrés
DA
Mariani
Samanta Gaertner
SG
Carriconde
Joaquim Freitas
JF
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D001938:Brazil / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004415:Dyspepsia / Q000453:epidemiology / Q000382:microbiology*; D004522:Educational Status; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000453:epidemiology; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D017678:Sex Distribution; D014505:Urban Population; D055815:Young Adult