Functional Age Predicted by Electronic Short Physical Performance Battery Can Detect Frailty Status in Older Adults

Figures & data

Table 1 Linear Regression Analysis Predicting Chronological Age From the Parameters of Short Physical Performance Battery in Development Cohort (n=717)

	Coefficient (B)	95% Confidence Interval	p-value
Balance score (increasing by 1 point)	−1.98	−2.56 to −1.40	<0.001
Walking speed (increasing by 1 m/s)	−5.21	−6.60 to −3.82	<0.001
Stand-up time (increasing by 1 s)	0.23	0.12 to 0.33	<0.001

Figure 1 Distributions of short physical performance battery (SPPB) total score and balance score, walking speed score, chair rise score in development cohort (n=717).

Figure 2 Scatterplot and fitted line by linear regression analysis showing (A) functional age and chronological age in development cohort (n=717) and (B) functional age and frailty index in validation cohort (n=117).

Table 2 Clinical Characteristics of Patients Included in the Validation Cohort, with Higher Functional Age and Lower Functional Age Group Defined by the Median Value of Functional Age (74.2 Years)

	Lower Functional Age (<74.2 years), N = 59		Higher Functional Age (≥74.2 years), N = 58		p-value^a
Chronological age	74.2	(7.2)	80.3	(5.3)	<0.001
Sex (male)	27	(45.8%)	32	(55.2%)	0.309
Comorbidities
Hypertension	25	(43.9%)	39	(68.4%)	0.008
Diabetes	13	(22.8%)	16	(28.1%)	0.519
Depression	12	(21.1%)	16	(28.1%)	0.514
Dementia	3	(5.3%)	8	(14.0%)	0.203^b
Frailty index	0.08	(0.05)	0.20	(0.13)	<0.001
Polypharmacy	26	(45.6%)	46	(80.7%)	<0.001
Fall history in 1 year	5	(8.8%)	19	(33.3%)	0.002^b
ADL dependency	3	(5.1%)	17	(29.3%)	<0.001^b
IADL dependency	11	(18.6%)	33	(56.9%)	<0.001

Notes: Data presented as number (%) or mean (standard deviation). ^aMann–Whitney test for continuous variables and χ² test for categorical variables. ^bFischer’s exact test.

Abbreviations: ADL, activity of daily livings; IADL, instrumental activities of daily living.

Figure 3 Receiver of characteristic (ROC) curves showing diagnostic performance of (A) functional age and (B) chronological age to detect frail status by frailty index in validation cohort (n=117).