Aim: To investigate the association between homebound status and functional decline over a two-year follow-up period and the sex difference in its association. 
Methods: The study subjects were 2,956 independently living older individuals (1,267 men: 1,679 women). Homebound were defined as individuals who left home less than once a week.Using a Cox proportional hazard model, we evaluated the association between homebound status and onset of functional dependence. 
Results: Of the 2,946 subjects, 223 (7.6%) were homebound. During the follow-up period, 153 subjects became functional dependence. After adjustment for locomotor function, cognitive function, depression state, age and household type, the hazard ratio for onset of functional dependence in association with homebound status remained significantly increased in men (HR, 3.12 [95% CI, 1.59–6.10]), but not in women (HR, 1.43 [95% CI, 0.87-2.35]). 
Conclusions: This study suggests that homebound status is a risk for functional dependence in both men and women. In men, being homebound despite intact functional ability was also a risk for functional dependence.