Patient prognosis and prediction model for taking Kampo formulas in dysmenorrhea: An observational study

Two representative Kampo formulas, keishibukuryogan and tokishakuyakusan, are frequently prescribed for patients with dysmenorrhea. We previously constructed a model that could predict which of these 2 formulas was most suitable, which is based on 4 subjective symptoms and 3 objective signs. To evaluate the prognosis of patients with dysmenorrhea using the established prediction model and assess the treatment outcomes between those treated in accordance with the prediction model and those who received various other treatments. In this retrospective, observational study, we included patients with menstrual pain who visited the Kampo Clinic at the Keio University Hospital for the first time between October 2014 and December 2020. These patients were monitored over a 90-day follow-up period. Participants were categorized into 2 groups: model-accordance and various-options. The progression of visual analogue scale (VAS) values was evaluated by determining the slopes from regression analysis between these 2 groups, with changes corroborated by the medical records. The study comprised 57 patients: 37 in the model-accordance group and 20 in the various-options group. Notably, the various-options group reported a significantly higher number of subjective symptoms (P = .03). The VAS value showed a decline, as indicated by the negative slope value of the regression line, across both groups - irrespective of their classification. There were no significant differences in the occurrence of adverse events between the 2 groups. The prognosis of patients with dysmenorrhea and the incidence of adverse events remained consistent, regardless of whether the treatment approach was in accordance with the prediction model or varied. Further studies are warranted to assess the prognosis when Kampo formulas are chosen based on the prediction model in the various-options population.