The Use of MoCA and Other Cognitive Tests in Evaluation of Cognitive Impairment in Elderly Patients Undergoing Arthroplasty

Abstract

Objective: To examine the prevalence and effect of cognitive impairment on treatment outcomes in elderly patients undergoing arthroplasty and to describe the feasibility of cognitive tests. Materials and Methods: The participants were 52 patients with a mean age of 78 years 11 months (SD: 3.3), waiting for primary arthroplasty. We translated Montreal Cognitive Assessment (MoCA) into Finnish and compared it with Mini-Mental State Examination (MMSE), Mini-Cog, and clock-drawing tests prior to and 3 months after the surgery. The ability to perform activities of daily living, depression, quality of life, and years of education were evaluated. Results: The mean MoCA score on the first visit was 20.7 (SD: 4.1). The pre- and postoperative cognitive tests implied there were no changes in cognitive functioning. Unambiguous delirium was detected in 6 patients. Delirium was not systematically assessed and consequently hypoactive delirium cases were possibly missed. Both MMSE and Mini-Cog found 3/6 of those and clock drawing and MoCA 6/6. Low preoperative MoCA, MMSE, and Mini-Cog scores predicted follow-up treatment in health-care center hospitals ( P = .02, .011, and .044, respectively). During the 5-year follow-up period, 11/52 patients died. Higher education was the only variable associated with survival. The survivors had attained the median of 8 (range: 4-19) years of education compared with 6 (range: 4-8) years among the deceased. Conclusion: The prevalence of cognitive impairment among older patients presenting for arthroplasty is high and mostly undiagnosed. It is feasible to use the MoCA to identify cognitive impairment preoperatively in this group. The clock-drawing test was abnormal in all patients with postoperative delirium, which could be used as a screening test. Higher education predicted survival on a 5-year follow-up period.