[LIMITATIONS OF QUESTIONNAIRE-BASED EVALUATION OF LOWER URINARY TRACT DYSFUNCTION IN ELDERLY PATIENTS].

(Purpose) Questionnaires are frequently used to evaluate subjective symptoms in clinical practice and research on lower urinary tract dysfunction. The usefulness and reliability of questionnaires such as the International Prostate Symptom Score (IPSS) and the Overactive Bladder Symptom Score (OABSS) are well known. However, elderly patients are often unable to fill out such questionnaires. There are no reports on the proportion of patients unable to complete these questionnaires and the background factors that make their use difficult. We conducted a prospective observational study to clarify these factors. (Materials and methods) Participants were 32 patients admitted to the rehabilitation ward of our hospital who were able to urinate on their own. The mean age was 82.9±6.9 years (65-97 years), and there were 11 men and 21 women. The main causes of hospitalization were orthopedic disease (17 cases), internal medical disease (9 cases), cerebrovascular disease (4 cases), and neurological disease (2 cases). The total score on the Functional Independence Measure (FIM) motor domains was used to evaluate patient motor function. The FIM cognitive domain total score and the Mini-Mental State Examination (MMSE) score were used to evaluate cognitive function. Patients were given Japanese versions of the IPSS, IPSS-Quality of Life, and OABSS, and asked to complete 12 questions by circling the responses. If they were unable to complete the questionnaire on their own, an occupational therapist assisted them for 10 minutes. Patients were divided into three groups according to their responses to the 12 items: self-completed, completed with assistance, and not completed even with assistance. The percentage in each group was determined. The number of questions that could not be answered by self-completion was defined as the number of missing questions. Correlations between the number of missing questions and age, FIM motor domain score, FIM cognitive domain score, and MMSE score were evaluated. We also performed univariate and multivariate analyses of patient background factors for two groups: patients who could not complete the questionnaire on their own and those who could complete the questionnaire on their own. Gender, age, medical history, FIM motor domain score, FIM cognitive domain score, and MMSE score were analyzed. Twenty-eight cases, excluding four cases with missing FIM and MMSE data, were examined. Based on the evaluation of the number of missing questions described above, cutoff values for age, FIM motor domains, FIM cognitive domains, and MMSE were set. Fisher's exact test and logistic regression analysis were performed. (Results) For the 12 questionnaire items, 21 patients (65.6%) were able to complete the questionnaire on their own, 6 patients (18.8%) were able to complete it with assistance, and 5 patients (15.6%) were not able to complete it even with assistance. Age, FIM motor domain score, FIM cognitive domain score, and MMSE score all showed significant correlations with the number of missing items, with correlation coefficients of 0.362 (p=0.0417), -0.435 (p=0.0183), -0.622 (p=0.000318), and -0.455 (p=0.0149), respectively. The univariate analysis showed that two background factors indicating cognitive decline prevented self-completion of the questionnaire: FIM cognitive domain score <21 points (p=0.0000518) and MMSE score <24 points (p=0.0377). Multivariate analysis showed that cognitive decline, as indicated by <21 points on FIM cognitive domains, (odds ratio 133, 95% confidence interval 7.29-2,430, p=0.000965) affected patients' inability to complete the questionnaire on their own.