Passive sedentary behavior (SB) may lead to adverse health outcomes; however, it remains unclear whether the factors relevant to passive SB differ between older adults with and without knee osteoarthritis (KOA). This cross-sectional study examined factors associated with passive SB among 688 community-dwelling older women with (n = 128) and without (n = 560) KOA. Passive SB (min/day) was assessed using the Japanese-translated version of the Measure of Older Adults' Sedentary Time questionnaire. Demographic, lifestyle, and psychosocial factors; pain; and physical performance were evaluated in multiple regression models with an interaction term concerning SB between the two groups. The mean (SD) total SB for those without and with KOA was 490.4 (200.9) min/day and 487.4 (185.8) min/day, respectively, and the majority of SB was passive, with no difference between groups. Passive SB was associated with an obese status and less time spent in group activities. However, no KOA-specific SB factors were identified. Therefore, effective interventions to promote social participation and weight loss, especially for individuals with obesity, may reduce passive SB, regardless of KOA. Longitudinal studies are warranted to identify causal relationships.
Keywords: ecological model; interaction term; osteoarthritis; physical activity; sedentary time.