Influence of Cognitive Impairment on Rehabilitation Received and Its Mediating Effect on Functional Recovery

Background: Cognitive impairment (CI) has been reported to negatively impact rehabilitation outcomes. Knowledge about differences in rehabilitation received in dependence of CI as a potential mediating factor is limited.

Objective: To analyze whether CI affects amount and frequency of rehabilitation received and if associations between CI and rehabilitation outcome are mediated by the provided amount of therapy.

Methods: Observational cohort study in ward-based geriatric rehabilitation consecutively including 373 patients (mean age 82.0±6.69 years, mean MMSE 23.66±5.31). Outcome measures were amount, frequency, and type of multi-professional therapy sessions and rehabilitation outcome assessed with the Barthel Index (BI). Cognitive status was measured with the Mini-Mental-State Examination (MMSE) classifying three patient subgroups according to cognitive status.

Results: Patients with more severe CI received least total therapy hours (TTH) (MMSE < 17, 13.67±6.58 versus MMSE 17-26, 16.12±7.19 and MMSE > 26, 17.79±8.88 h, p = 0.014) and were less often included in occupational therapy (MMSE < 17, 48.9%versus MMSE 17-26, 65.5%and MMSE > 26, 71.4%, p = 0.019) and group-based physiotherapy (MMSE < 17, 73.3%versus MMSE 17-26, 88.5%and MMSE > 26, 81.2%, p = 0.027). Regression models showed that CI negatively impacted TTH (β= 0.24, p = 0.003) and rehabilitation outcome (β= 0.41, p = 0.008). In the mediation model, TTH accounted for 23.18%(p < 0.001) of the relationship between CI and rehabilitation outcome.

Conclusion: Cognitive impairment negatively impacted rehabilitation received. The lower TTH partly mediated the negative association between CI and rehabilitation outcome. Future research should identify specific barriers to therapy provision and optimal length, intensity, and dosage of rehabilitation programs to optimize rehabilitation outcomes in CI.