Obesity, Even in the Metabolically Healthy, Increases the Risk of Poor Physical Performance: A Cross-Sectional Study of Older People in a Chinese Community

Figures & data

Table 1 Characteristics of Study Group, Stratified by Metabolically Healthy and Obesity Status

Variables	MHNO	MHO	MUHNO	MUHO	P-value
N, %	694 (49.75)	50 (3.58)	525 (37.63)	126 (9.03)	–
Age (y)	72.12 ± 6.06	71.94 ± 5.59	71.79 ± 5.66	70.95 ± 5.71*	0.214
Female, n (%)	336 (48.4)	32 (64.0)*	368 (70.1)^*, #	88 (69.8)*	<0.001
Hight, (cm)	160.88 ± 9.55	158.95 ± 8.06	159.06 ± 8.59*	158.16 ± 8.15*	0.001
Weight, (kg)	57.63 ± 10.23	74.30 ± 7.73*	62.08 ± 9.32^*, #	75.33 ± 8.21^*, #, ^	<0.001
BMI, (kg/m^2)	22.19 ± 2.83	29.40 ± 1.28*	24.45 ± 2.26^*, #	30.09 ± 1.83^*, #, ^	<0.001
WC, (cm)	85.15 ± 8.69	101.84 ± 6.73*	91.91 ± 7.38^*, #	102.93 ± 7.17^*,^	<0.001
Widowed, n (%)	125 (18.1)	15 (30.6)*	110 (21.1)^#	24 (19.0)^#	0.141
Living alone, n (%)	105 (15.2)	12 (24.5)	86 (16.5)	14 (11.1)^#	0.154
Famer, n (%)	380 (54.8)	26 (52.0)	313 (59.6)	76 (60.3)	0.265
IPAQ (Met/wk)	4617 (2027, 8891)	4284 (2564, 7714)	4069 (1743, 7518)	3599 (1743, 6573)	0.073
Education, n (%)					0.574
Primary or below	518 (75.1)	40 (81.6)	414 (79.6)	97 (77.0)
Secondary or above	172 (24.9)	9 (18.4)	106 (20.4)	29 (23.0)
Smoking, n (%)					0.001
Current smokers	157 (22.8)	5 (10.2)	74 (14.3)	15 (11.9)
Never smokers	403 (58.5)	35 (71.4)	371 (71.8)	88 (69.8)*
Ex-smokers	129 (18.7)	9 (18.4)	72 (13.9)	23 (18.3)
Drinking, n (%)					0.001
Daily drinkers	115 (16.9)	4 (8.2)	50 (9.8)	10 (8.1)
Occasional drinkers	106 (15.6)	6 (12.2)	55 (10.8)	14 (11.3)
Former drinkers	89 (13.1)	5 (10.2)	49 (9.6)	9 (7.3)
Never drinkers	370 (54.4)	34 (69.4)	355 (69.7)*	91 (73.4)*
Chronic medical conditions^a					<0.001
0	74 (10.7)	6 (12.0)	3 (0.6)^*, #	2 (1.6)^*, #
1–2	460 (66.3)	31 (62.0)	239 (45.5)^*, #	47 (37.3)^*, #
≥3	160 (23.1)	13 (26.0)	283 (53.9)^*, #	77 (61.1)^*, #
Physical performance
Grip strength (kg)	23.95 ± 8.85	21.39 ± 7.61	21.85 ± 8.59*	21.33 ± 7.97*	<0.001
Relative grip strength (kg/kg)	0.415 ± 0.13	0.285 ± 0.09*	0.350 ± 0.12^*, #	0.281 ± 0.09^*, ^	<0.001
Walking speed (m/s)	1.09 ± 0.23	1.00 ± 0.22*	1.05 ± 0.24*	1.00 ± 0.20^*,^	<0.001
TUGT (s)	9.78 ± 3.34	10.44 ± 2.81	10.39 ± 4.23	11.04 ± 3.62^*,^	<0.001
MetS components
SBP (mmHg)	129.88 ± 19.01	129.10 ± 16.44	138.07 ± 19.94^*, #	137.20 ± 18.62^*, #	<0.001
DBP (mmHg)	73.27 ± 11.06	73.01 ± 9.57	74.51 ± 11.29	73.81 ± 9.60	0.251
FPG (mmol/L)	5.30 ± 1.05	5.38 ± 0.91	6.44 ± 1.79^*, #	6.37 ± 1.50^*, #	<0.001
TG (mmol/L)	1.08 ± 0.43	1.22 ± 0.38	2.00 ± 1.39^*, #	1.92 ± 0.86^*, #	<0.001
HDL (mmol/L)	1.54 ± 0.33	1.44 ± 0.24*	1.34 ± 0.41*	1.28 ± 0.29^*, #	<0.001

Notes: Data represent mean ± SD, median (interquartile range 25–75%), or percentage. ^aHistory of hypertension, dyslipidemia, diabetes, stroke, myocardial infarction, congestive heart failure, arthritis, gout, and cancer. *P < 0.05 versus MHNO; ^#P < 0.05 versus MHO; ^{^}P < 0.05 versus MUHNO.

Abbreviations: MHNO, metabolically healthy nonobese; MHO, metabolically healthy obese; MUHNO, metabolically unhealthy nonobese; MUHO, metabolically unhealthy obese; BMI, body mass index; WC, waist circumference; IPAQ, International Physical Activity Questionnaire; TUGT, timed up and go test; SBP, systolic blood pressure; DBP, diastolic blood pressure; FPG, fasting plasma glucose; TG, total triglycerides; HDL, high-density lipoprotein cholesterol.

Figure 1 (A) Mean relative grip strength (kg/kg), (B) Mean 4-m walking speed (m/s), (C) Mean TUGT (s). Statistical analysis was performed using ANCOVA. P-values represent the result of Bonferroni corrections after adjusting for age, sex, educational level, marital status, living situation, drinking, smoking, occupation, International Physical Activity Questionnaire (IPAQ), the number of chronic medical conditions. *P < 0.05 versus MHNO; ^#P < 0.05 versus MHO; ^{^}P < 0.05 versus MUHNO.

Abbreviations: TUGT, timed up and go test; ANCOVA, analysis of covariance; MHNO, metabolically healthy nonobese; MHO, metabolically healthy obese; MUHNO, metabolically unhealthy nonobese; MUHO, metabolically unhealthy obese.

Table 2 Univariate Regression Analysis of the Association Between Metabolic Components, Obesity with Physical Performance Measures

Variables	Relative Grip Strength		4-m Walking Speed		TUGT
	β	P-value	β	P-value	β	P-value
Impaired fasting glucose	−0.103	<0.001	−0.063	0.019	0.077	0.004
Elevated triglycerides	−0.135	<0.001	−0.042	0.115	−0.001	0.977
Low HDL	−0.165	<0.001	−0.030	0.262	0.046	0.084
High blood pressure	−0.084	0.002	−0.077	0.004	0.118	<0.001
Abdominal obesity	−0.384	<0.001	−0.095	<0.001	0.065	0.016

Note: β = standardized coefficient.

Abbreviations: TUGT, timed up-and-go test; HDL, high-density lipoprotein cholesterol.

Table 3 Multivariate Linear Regression Analysis of the Association Between Metabolic Components with Physical Performance Measures

Variables	Relative Grip Strength			4-m Walking Speed			TUGT
	R^2	β	P-value	R^2	β	P-value	R^2	β	P-value
Impaired fasting glucose	0.313	−0.071	0.003	0.231	−0.015	0.551	0.186	0.027	0.289
Elevated triglycerides	0.312	−0.062	0.008	0.232	−0.027	0.271	0.185	−0.007	0.772
Low HDL	0.311	−0.045	0.054	0.231	0.016	0.528	0.186	0.024	0.344
High blood pressure	0.311	−0.049	0.052	0.231	0.015	0.587	0.186	0.021	0.453
Abdominal obesity	0.354	−0.230	<0.001	0.232	−0.035	0.173	0.186	0.033	0.216

Notes: β = standardized coefficient; the model was fully adjusted for age, sex, educational level, marital status, living situation, drinking, smoking, occupation, International Physical Activity Questionnaire (IPAQ), the number of chronic medical conditions.

Abbreviations: TUGT, timed up-and-go test; HDL, high-density lipoprotein cholesterol.

Table 4 Stepwise Multivariate Linear Regression Analysis of the Association Between Metabolic Syndrome with Relative Grip Strength

Variables	β	P-value	Tolerance	VIF
Age	−0.130	<0.001	0.930	1.075
Sex	−0.446	<0.001	0.879	1.138
IPAQ	0.108	<0.001	0.983	1.018
Education	0.109	<0.001	0.925	1.081
Living situation	−0.065	0.042	0.934	1.070
Metabolic syndrome	−0.163	<0.001	0.949	1.053

Notes: β = standardized coefficient; the model was fully adjusted for age, sex, educational level, marital status, living situation, drinking, smoking, occupation, International Physical Activity Questionnaire (IPAQ), the number of chronic medical conditions, and metabolic components but excluding abdominal obesity.

Abbreviation: VIF, variance inflation factor.

Figure 2 The circled points and error bars represent adjusted mean values and 95% Cl of relative grip strength, respectively. Statistical analysis was performed using ANCOVA. P-values represent the result of Bonferroni corrections after adjusting for age, sex, educational level, occupation, International Physical Activity Questionnaire (IPAQ), the number of chronic medical conditions. Means (95% CI) for the groups of 0 metabolic component, 1–2 metabolic components, and 3–5 metabolic components were 0.439 (0.415–0.463), 0.389 (0.380–0.397) and 0.352 (0.343–0.361), respectively. *P < 0.05 versus 0 metabolic component; ^#P < 0.05 versus 1–2 metabolic components.