Impact of Transtheoretical Model Staging on Health Outcomes in Japanese Men Aged 40-70: A Propensity Score Matching Analysis.

Introduction: Japan's aging population and rising healthcare costs have prompted initiatives like the National Health Program to promote preventive care. The transtheoretical model (TTM) assesses readiness for behavior change, focusing on diet and exercise. This study compared health behaviors and outcomes between Japanese men in the "precontemplation" stage (no intention to change) and those in the "contemplation or higher" stage over four years. Methods: This retrospective study analyzed data from 10,812 men aged 40-70 using the 2013-2017 Specific Health Checkups. Participants were grouped by TTM stages and matched by propensity scores to minimize confounding. Outcomes, including body mass index (BMI), blood pressure, and self-reported behaviors, were compared using χ Results: At baseline, precontemplation-stage men had better health metrics but exhibited higher rates of unhealthy behaviors, such as smoking. After four years, significant differences were observed only in high-density lipoprotein (HDL) and creatinine levels for men under 49, and in HDL, BMI, dyslipidemia medication, and eating speed for those 49 or older (p < 0.05). Conclusions: Men in the precontemplation stage face challenges related to health awareness and readiness for change. Tailored interventions, including health education and motivational interviewing, support long-term health improvements. Future research should explore personalized interventions and broader health determinants for sustained behavior change.