Associations between obesity and cognitive impairment in the Chinese elderly: an observational study

Figures & data

Table 1 Baseline characteristics of participants

Characteristics	Mean ± SD or P50 (P25, P75) or number (percentage)
Age (years)	79 (73, 83)
Male, n (%)	568 (51.6)
Education level, n (%)
Middle school and above	292 (26.5)
Primary school	384 (34.9)
Illiteracy	424 (38.5)
BMI (kg/m^2)	23.23±3.65
BMI category (kg/m^2), n (%)
18.5–23.9	575 (52.2)
<18.5	93 (8.4)
24.0–27.9	327 (29.7)
≥28.0	105 (9.5)
Waist (cm)	73 (67, 81)
Waist–hip ratio	0.82 (0.78, 0.86)
Abdominal obesity, n (%)	206 (18.7)
Smoking, n (%)	278 (25.2)
Drinking, n (%)	207 (18.8)
Diabetes, n (%)	325 (29.5)
Hypertension, n (%)	383 (34.8)
Hypercholesterolemia, n (%)	79 (7.2)
Cognitive impairment, n (%)	185 (16.8)
MMSE score	26 (23, 28)

Abbreviations: BMI, body mass index; MMSE, Mini-Mental State Examination.

Table 2 Characteristics between participants with normal cognition and participants with cognitive impairment

Variables	Normal cognition (N=915)	Cognitive impairment (N=185)	P-value
Age (years)	78.00 (72.00, 83.00)	82.00 (77.50, 85.50)	<0.001
Male, n (%)	480 (52.5)	88 (47.6)	0.225
Education level, n (%)			0.051
Middle school and above	244 (26.7)	48 (25.9)
Primary school	306 (33.4)	78 (42.2)
Illiteracy	365 (39.9)	59 (31.9)
BMI (kg/m^2)	23.40±3.64	22.43±3.56	0.001
BMI category (kg/m^2), n (%)			0.001
18.5–23.9	458 (50.1)	117 (63.2)
<18.5	74 (8.1)	19 (10.3)
24.0–27.9	294 (32.1)	33 (17.8)
≥28.0	89 (9.7)	16 (8.6)
Waist (cm)	73.00 (67.00, 81.00)	72.00 (65.00, 79.50)	0.071
Waist–hip ratio	0.82 (0.78, 0.85)	0.82 (0.78, 0.86)	0.092
Abdominal obesity, n (%)	159 (17.4)	47 (25.4)	0.011
Smoking, n (%)	233 (25.5)	45 (24.3)	0.745
Drinking, n (%)	182 (19.9)	25 (13.5)	0.043
TC (mmol/L)	4.18±1.09	4.19±1.11	0.915
TG (mmol/L)	1.18 (0.85, 1.61)	1.12 (0.83, 1.58)	0.302
LDL-C (mmol/L)	2.49±0.91	2.43±0.96	0.392
HDL-C (mmol/L)	1.33 (1.08, 1.62)	1.36 (1.04, 1.63)	0.979
Hypercholesterolemia, n (%)	61 (6.7)	18 (9.7)	0.141
Hypertension, n (%)	307 (33.6)	76 (41.1)	0.050
Diabetes, n (%)	265 (29.0)	60 (32.4)	0.345
MMSE score	27 (25, 28)	13 (9, 16)	<0.001

Note: Data are shown as mean ± SD or P50 (P25, P75) or number (percentage).

Abbreviations: BMI, body mass index; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; MMSE, Mini-Mental State Examination; TC, total cholesterol; TG, triglyceride.

Table 3 Association of body mass index with cognitive impairment

Adjustment	OR	95% CI	P-value
Model 1 (kg/m^2)
18.5–23.9	1
<18.5	1.005	0.584–1.731	0.985
24.0–27.9	0.439	0.291–0.664	<0.001
≥28.0	0.704	0.398–1.244	0.227
Model 2 (kg/m^2)
18.5–23.9	1
<18.5	0.877	0.501–1.535	0.645
24.0–27.9	0.450	0.296–0.685	<0.001
≥28.0	0.740	0.414–1.321	0.308
Model 3 (kg/m^2)
18.5–23.9	1
<18.5	0.857	0.486–1.510	0.592
24.0–27.9	0.458	0.300–0.698	<0.001
≥28.0	0.708	0.394–1.270	0.247
Model 4 (kg/m^2)
18.5–23.9	1
<18.5	1.033	0.595–1.793	0.907
24.0–27.9	0.439	0.289–0.667	<0.001
≥28.0	0.732	0.412–1.301	0.288
Model 5 (kg/m^2)
18.5–23.9	1
<18.5	0.876	0.493–1.556	0.651
24.0–27.9	0.458	0.298–0.703	<0.001
≥28.0	0.758	0.419–1.370	0.359

Notes: Model 1: no adjustment; model 2: adjust for age, gender; model 3: adjust for age, gender, drinking, smoking, education level; model 4: adjust for hypercholesterolemia, hypertension, diabetes; model 5: adjust for age, gender, smoking, drinking, education level, hypercholesterolemia, hypertension, diabetes.

Table 4 Association of abdominal obesity with cognitive impairment

Adjustment	OR	95% CI	P-value
No adjustment	1.619	1.116–2.350	0.011
Adjust for drinking, smoking	1.619	1.113–2.354	0.012
Adjust for age, education level	1.473	1.006–2.156	0.046
Adjust for hypercholesterolemia, hypertension, diabetes	1.667	1.139–2.438	0.008
Adjust for age, education level, hypercholesterolemia, hypertension, diabetes	1.532	1.037–2.263	0.032