Validity of the short physical performance battery for screening for frailty syndrome among older people in the Brazilian Amazon region. A cross-sectional study

ABSTRACT BACKGROUND: Environmental and population characteristics seem to influence the variation in cutoff points of the Short Physical Performance Battery (SPPB) for diagnosing frailty syndrome among older adults. OBJECTIVE: To verify the validity of the SPPB for screening for frailty syndrome among older adults in the Amazonian context. DESIGN AND SETTING: Cross-sectional population-based study on older adults in the urban area of Coari (AM), Brazil. METHODS: In total, 264 older adults (60 years of age or over) were included. Frailty syndrome was defined using the Fried phenotype criteria. The SPPB cutoff points were compared in relation to frailty and validity measurements were calculated for the test. RESULTS: A strong association between poor physical performance and frailty was identified (P < 0.001). The cutoff point of 6 demonstrated the best validity measurements for frailty in the sample studied (sensitivity: 0.28; specificity: 0.94; accuracy: 0.88; area under the receiver operating characteristic curve, AUC-ROC: 0.61; likelihood ratio, LR+: 4.44; LR-: 0.77; prevalence: 8.3%; post-test probability, PTP+: 0.32; PTP-: 0.07), with emphasis on high specificity and the positive likelihood ratio value. CONCLUSION: The SPPB was shown to be useful for screening frail older adults in the Amazon region. The score of 6 demonstrated the best cutoff point for this population. This could be used in healthcare services for diagnostic screening for frailty among older people within the Amazonian context.

背景：环境与人口特征似乎会影响老年衰弱综合征诊断所用的简短体能测试量表（Short Physical Performance Battery, SPPB）的截断值差异。
研究目的：验证亚马逊地区老年人群中SPPB用于筛查衰弱综合征的有效性。
研究设计与研究场景：一项基于人群的横断面研究，研究对象为巴西亚马逊州科阿里市城区的老年人。
研究方法：本研究共纳入264名60岁及以上的老年人。采用Fried表型标准定义衰弱综合征。将SPPB的不同截断值与衰弱状态进行关联分析，并计算该量表的效度指标。
研究结果：本研究发现躯体功能低下与衰弱存在强相关性（P < 0.001）。在本研究样本中，截断值6展现出最优的衰弱筛查效度指标：灵敏度0.28、特异度0.94、准确度0.88、受试者工作特征曲线下面积（AUC-ROC）0.61、阳性似然比（LR+）4.44、阴性似然比（LR-）0.77、人群患病率8.3%、试验后阳性概率（PTP+）0.32、试验后阴性概率（PTP-）0.07，其中以高特异度与阳性似然比数值最为突出。
研究结论：SPPB可有效用于亚马逊地区老年衰弱人群的筛查。得分6分为本研究人群的最优截断值，可应用于亚马逊地区医疗机构的老年衰弱筛查工作。