Costs of Diagnosis and Treatment of Helicobacter Pylori Infection: When Does Choosing The Treatment Regimen Based on Susceptibility Testing Become Cost Effective?

OBJECTIVE: Antibiotic-resistant Helicobacter pylori (H. pylori) strains are becoming increasingly prevalent. Currently, most physicians treat H. pylori infections without relying on antimicrobial susceptibility testing to choose the best regimen. This study was conducted to evaluate whether routine pretreatment susceptibility testing is cost effective from a third party payer point of view. METHODS: A decision model was devised to compare direct costs and outcome for diagnosis and treatment over 1 year for two different strategies. Strategy A: Endoscopy plus biopsy followed by an empirical antibiotic treatment of H. pylori-positive ulcer patients. Treatment failure was followed by reendoscopy with biopsy and antibiotic susceptibility testing and a second treatment. Strategy B: Endoscopy as in strategy A now followed by antibiotic susceptibility testing and tailored antibiotic treatment. Treatment failure was handled as in strategy A. RESULTS: Following through with strategy A or B, the overall cure rate for both strategies was virtually identical. Therefore, cost effectiveness is defined as money saved per patient by using strategy B, while achieving similar effectiveness (cure rates). As an example we compared therapies for a population with known parameters for antibiotic resistance as well as cure rates. Pretreatment susceptibility testing would save 37, 000 per 1, 000 patients treated. According to our model (equal therapy-price assumption in strategy A and B), pretreatment susceptibility testing for metronidazole is less costly for all the reported populations worldwide. CONCLUSIONS: Our decision analysis suggests that routine pretreatment susceptibility testing can be cost effective under various settings. The model presented is easily transferable to any population as long as the following variables are known: 1) the proportion of H. pylori strains in the population that are resistant to the antibiotics of the initial regimen; 2) the cure rate in sensitive H. pylori strains; 3) the cure rate in resistant H. pylori strains; and 4) the costs for diagnosis and treatment used.