Cross-lagged panel analysis of kinesiophobia and frailty in older patients undergoing radical prostatectomy

Background Kinesiophobia and frailty are common concerns during postoperative recovery in older adults, but their longitudinal relationship after radical prostatectomy (RP) remains unclear. This study examined changes in kinesiophobia and frailty and their reciprocal prospective associations during the first 3 months after RP. Methods A prospective longitudinal study included 380 patients aged ≥65 years undergoing RP. Kinesiophobia and frailty were assessed at 24–48 hours, 1 month, and 3 months postoperatively using the TSK-17 and TFI. Cross-lagged panel models were estimated using robust maximum likelihood with full information maximum likelihood for missing data and adjustment for prespecified covariates. Complete-case analysis was performed as a sensitivity analysis. Results Kinesiophobia and frailty both decreased significantly over the 3-month follow-up (both P < 0.001). T1 frailty was prospectively associated with T2 kinesiophobia ( β = 0.210, 95% CI 0.121–0.300, P < 0.001), whereas T1 kinesiophobia was not associated with T2 frailty ( β = 0.068, 95% CI −0.034–0.170, P = 0.193). From T2 to T3, significant prospective associations were observed in both directions: kinesiophobia with subsequent frailty ( β = 0.278, 95% CI 0.181–0.374, P < 0.001) and frailty with subsequent kinesiophobia ( β = 0.154, 95% CI 0.069–0.239, P < 0.001). Conclusions Kinesiophobia and frailty were dynamically related during early recovery after RP, with their prospective associations varying across postoperative stages. These findings highlight the importance of considering both constructs over time and may help inform stage-specific monitoring during postoperative recovery.