Relationship between peripheral arterial disease and incident disability among elderly Japanese: The Tsurugaya project

Aim: The aim of this study was to investigate whether peripheral arterial disease (PAD) is predictive of disability and whether the relationship between PAD and disability can be fully explained by baseline physical functions. Methods: We followed for five years 783 Japanese aged 70 years or older without a disability at baseline in 2003. We defined participants certificed as requiring long-term care as having incident disability. The hazard ratio (HR) and 95% confidence interval (95% CI) for incident disability were calculated using the Cox proportional hazards model. Results: After adjusting for possible confounders other than physical function, the HR of incident disability among participants with PAD was 1.86 (95%CI: 1.06 to 3.26). Although the risk was attenuated (HR= 1.63, 95%CI: 0.92 to 2.86) after adding baseline physical function as a covariate, the HR was still high. Furthermore, the relation was not statistically significant, but the group with higher physical function and PAD also had a higher HR of incident disability than those who had higher physical function without PAD. Conclusion: PAD is an important predictor of disability even if the level of baseline physical function is high.