Preoperative Predictors of Instrumental Activities of Daily Living Disability in Older Adults 6 Months After Knee Arthroplasty.

OBJECTIVE: To investigate preoperative predictors of instrumental activities of daily living (IADL) disability in older adults 6 months after knee arthroplasty (KA). DESIGN: Prospective cohort study. SETTING: General hospital with an orthopedic surgery department. PARTICIPANTS: Two hundred twenty (N=220) patients 65 years or older with total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: IADL status was evaluated for 6 activities. Participants chose "able," "need help," or "unable" according to their capacity of executing these IADL. If they chose "need help" or "unable" for 1 or more items, they were defined as "disabled." Their usual gait speed (UGS), range of motion for the knee, isometric knee extension strength (IKES), pain status, depressive symptoms, pain catastrophizing, and self-efficacy were evaluated as predictors. Baseline and follow-up assessments were conducted 1 month before and 6 months after KA, respectively. Logistic regression analyses with IADL status as the dependent variable were performed at follow-up. All models were adjusted using age, sex, severity of the knee deformity, operation type (TKA or UKA), and preoperative IADL status as covariates. RESULTS: In total, 166 patients completed the follow-up assessment, and 83 (50.0%) reported IADL disability 6 months after KA. Preoperative UGS, IKES on the non-operated side, and self-efficacy were statistically significantly different between those with a disability at follow-up and those who did not and were therefore included in logistic regression models as independent variables. UGS (odds ratio, 3.22; 95% CI, 1.38-7.56; P=.007) was determined as a significant independent variable. CONCLUSIONS: The present study demonstrated the importance of evaluating preoperative gait speed to predict the presence of IADL disability in older adults 6 months after KA. Patients with poorer preoperative mobility should be provided careful postoperative care and treatment.

Psychological factors associated with instrumental activities of daily living disability in older adults with moderate to severe knee osteoarthritis.

BACKGROUND: The population of older adults with knee osteoarthritis (OA)-related disabilities is increasing globally. However, studies regarding instrumental activities of daily living (IADL) in older adults with knee OA are limited. OBJECTIVE: This study investigated the psychological factors associated with IADL disability in older adults with moderate to severe knee OA. METHODS: A cross-sectional study was conducted on 179 patients with knee OA aged ⩾ 65 years. The six-item short form of the Pain Catastrophizing Scale (PCS-6), the four-item short form of the Pain Self-Efficacy Questionnaire (PSEQ-4), and the fifteen-item Geriatric Depression Scale (GDS-15) were used to assess psychological factors. The participants were divided into IADL disabled and non-disabled groups. Binary logistic regression analyses were performed with the IADL disability status as the dependent variable. The PCS-6, PSEQ-4, and GDS-15 tools were included as independent variables in the logistic regression model. RESULTS: Of the 179 participants, 88 (49.1%) showed disability in conducting IADL. PSEQ-4 (odds ratio = 0.90, 95%; confidence interval = 0.82-0.99, p= 0.02) was a significant independent variable among all psychological factors. CONCLUSION: Even after controlling for cofounders, our study found that self-efficacy, assessed using the PSEQ-4, was related to IADL disability in older adults with moderate to severe knee OA.

Gait speed and pain status as discriminatory factors for instrumental activities of daily living disability in older adults with knee osteoarthritis.

AIM: Factors related to instrumental activities of daily living disability in older adults with knee osteoarthritis are unclear. This study aimed to examine the discriminatory accuracy for the presence of instrumental activities of daily living disability in older adults with knee osteoarthritis by combining two factors of gait ability and pain status. METHODS: A cross-sectional study was conducted on 114 patients with knee osteoarthritis aged ≥ 65 years. Participants were divided into instrumental activities of daily living disabled or non-disabled groups. A logistic regression model was created with usual gait speed and knee injury and osteoarthritis outcome score-pain subscale as independent variables for discriminating the presence of instrumental activities of daily living disability. The area under the receiver operating characteristic curve was inspected to determine discriminatory accuracy of the logistic regression model, usual gait speed, knee injury and osteoarthritis outcome score-pain subscale. RESULTS: Of the 114 patients, 26 (22.8%) had instrumental activities of daily living disability. The area under the curves was 0.91 (95% confidence interval: 0.85-0.96) for the logistic regression model, 0.78 (95% confidence interval: 0.68-0.89) for usual gait speed, and 0.73 (95% confidence interval: 0.61-0.84) for knee injury and osteoarthritis outcome score-pain subscale. CONCLUSIONS: This study showed that gait speed and pain status were independent discriminatory factors and combining these factors to discriminate more accurately the presence or absence of instrumental activities of daily living disability in older adults with knee osteoarthritis was important. Geriatr Gerontol Int 2021; 21: 683-688.