Reproducibility of a symptom response to omeprazole therapy in functional dyspepsia evaluated by a random-starting-day trial design.
BACKGROUND
Satisfactory treatment options for functional dyspepsia are lacking. Single subject trial designs may identify subgroups of patients with a uniform response to therapy.


OBJECTIVE
To test reproducibility of response in a new random-starting-day trial design developed to identify acid-related symptoms in functional dyspepsia.


METHODS
One hundred and nineteen patients with functional dyspepsia completed a 12-day, double-blind random-starting-day trial with an initial placebo run-in followed by switch to omeprazole on a randomized and blinded day (between days 5 and 9) with active treatment continuing for the rest of the trial. Response was defined as a sustained > or =50% reduction of a daily symptom-score within 3 days of active treatment. Fifty-nine patients repeated the random-starting-day trial at relapse of symptoms.


RESULTS
After exclusion of placebo responders, 14% (15 of 106) were classified as responders in the first and 20% (10 of 50) in the subsequent random-starting-day trial series. Sixty-eight per cent (40 of 59) of the patients reproduced their initial response with a chance-corrected agreement of 0.29. Comparing response patterns using different symptom rating-scales showed good correlation (kappa 0.60).


CONCLUSIONS
Reproducibility of response in a random-starting-day trial was imperfect, mainly because of the low response rates and strict response criteria. Lack of symptom stability impairs the value of the random-starting-day trial and only patients with frequent and stable symptoms should be evaluated in this design.
Department of Medical Gastroenterology, Glostrup University Hospital, Glostrup, Denmark.
L G
LG
Madsen
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P
Bytzer
D000897:Anti-Ulcer Agents / Q000627:therapeutic use*; D004311:Double-Blind Method; D004415:Dyspepsia / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009853:Omeprazole / Q000627:therapeutic use*; D015203:Reproducibility of Results
D000897:Anti-Ulcer Agents; D009853:Omeprazole