Cost-utility analysis of treatment strategies for chronic constipation in Japan

Chronic constipation reduces quality of life and imposes a significant economic burden. The introduction of novel agents in Japan has expanded treatment options. This study aimed to establish a cost-effective treatment strategy, considering clinical utility and patient satisfaction.

Nine treatment strategies were developed, each consisting of three consecutive treatment options selected from five drugs: magnesium oxide (MgO), lubiprostone, linaclotide, elobixibat, and PEG formulation. A Markov state-transition model was used to estimate costs and outcomes. Effectiveness data were derived from a network meta-analysis of spontaneous bowel movements within 24 h (SBM24) using domestic trial data. Expected costs and quality-adjusted life years (QALYs) were calculated from the healthcare payer's perspective.

In the network meta-analysis, lubiprostone had the highest relative risk for SBM24 (2.36), followed by lactulose (1.84) and elobixibat (1.71). Compared to MgO, the lubiprostone-elobixibat-PEG formulation strategy had additional costs of JPY 8,069.5 and a QALY gain of 0.0710, resulting in an incremental cost-effectiveness ratio (ICER) of JPY 113,709/QALY-well below the willingness-to-pay threshold of JPY 5-6 million/QALY. All strategies had ICERs below JPY 200,000/QALY, indicating favorable cost-effectiveness. Sensitivity analyses confirmed that the lubiprostone-elobixibat-PEG formulation strategy remained the most cost-effective, demonstrating its robustness.

The lubiprostone-elobixibat-PEG formulation strategy showed the most favorable cost-effectiveness profile. In addition, novel treatment options, including lubiprostone, linaclotide, elobixibat, and PEG formulation, were found to be cost-effective compared to MgO. Further research is warranted to confirm these findings and support their application in clinical practice.