The Japan Frailty Scale is a promising screening test for frailty and pre-frailty in Japanese elderly people
Ryuichiro Egashira, Tomoharu Sato, Akimitsu Miyake, Mariko Takeuchi, Mai Nakano, Hitomi Saito, Misaki Moriguchi, Satoko Tonari, Keisuke Hagihara
Abstract
Frailty is one of the most important problems in a super-aged society. It is necessary to identify frailty quickly and easily at the bedside. We developed a simple patient-reported frailty screening scale, the Japan Frailty Scale (JFS), based on the aging concept of Kampo medicine. Eight candidate questions were prepared by Kampo medicine experts, and a simple prediction model was created in the development cohort (n = 434) and externally validated in an independent validation cohort (n = 276). The physical indicators and questionnaires associated with frailty were also comprehensively evaluated. The reference standard for frailty or pre-frailty was determined based on the Kihon checklist. In the development cohort, four questions, nocturia (0-2), lumbago (0-2), cold sensitivity (0-2), exhaustion (0-4), and age (0-1) were selected by multivariable logistic regression analysis. The total JFS score is 0-11. Receiver-operating characteristic curve analysis of the JFS for identifying frailty status showed moderately good discrimination (area under the curve (AUC) = 0.78, 95 % confidence interval (CI): 0.73-0.82). At the JFS cutoff value of 3/4 for frailty or pre-frailty, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 86.9 %, 53.3 %, 62.8 %, and 81.7 %, respectively. External validation of the JFS showed moderately good discrimination (AUC = 0.76, 95 % CI: 0.70-0.81). The sensitivity, specificity, PPV, and NPV were 79.9 %, 61.4 %, 69.3 %, and 73.7 %, respectively. These results indicate that the JFS is a promising patient-reported clinical scale for early identification of pre-frail/frail patients at the bedside in primary care.