Artificial intelligence-based chest computed tomography assessment of bone, vascular, and epicardial adipose changes in type 2 diabetes

Table 1 Baseline characteristics of patients with non-type 2 diabetes mellitus and type 2 diabetes mellitus, n (%)/median (interquartile range)

Variables	Total	Non-T2DM patients	T2DM patients	P value
n	4589	3220	1369
Baseline characteristic
Age (years)	55.00 (45.00, 63.00)	53.00 (41.00, 60.00)	60.00 (53.00, 67.00)	< 0.001
BMI (kg/m2)	23.73 (21.48, 25.95)	23.62 (21.40, 25.84)	24.02 (21.88, 26.22)	< 0.001
Male sex	2665 (58.07)	1756 (54.53)	909 (66.40)	< 0.001
Smoke	946 (20.61)	650 (20.19)	296 (21.62)	0.271
Alcohol	709 (15.45)	543 (16.86)	166 (12.13)	< 0.001
Hypertension	2377 (51.80)	1248 (38.76)	1129 (82.47)	< 0.001
Dyslipidemia	2598 (56.61)	1646 (51.12)	952 (69.54)	< 0.001
Laboratory findings
HDL-cholesterol (mmol/L)	1.09 (0.90, 1.34)	1.14 (0.95, 1.39)	0.95 (0.78, 1.21)	< 0.001
LDL-cholesterol (mmol/L)	2.67 (2.04, 3.37)	2.78 (2.19, 3.49)	2.35 (1.74, 3.06)	< 0.001
Total cholesterol (mmol/L)	4.40 (3.68, 5.36)	4.53 (3.84, 5.45)	4.05 (3.31, 5.12)	< 0.001
Triglyceride (mmol/L)	1.52 (1.03, 2.35)	1.44 (1.00, 2.21)	1.70 (1.13, 2.65)	< 0.001
Fast glucose (mmol/L)	5.44 (4.89, 6.52)	5.18 (4.79, 5.69)	8.01 (6.10, 11.20)	< 0.001
CT findings
BMD (mg/cm3)	173.37 (149.18, 196.47)	176.72 (151.09, 200.71)	167.90 (144.78, 187.61)	< 0.001
EAT volume (cm3)	139.89 (95.68, 196.14)	132.59 (91.86, 184.31)	160.57 (111.34, 215.94)	< 0.001
EAT density (HU)	-77.06 (-82.28, -72.03)	-77.79 (-82.55, -72.99)	-75.07 (-81.41, -69.36)	< 0.001
CACS	0.00 (0.00, 60.53)	0.00 (0.00, 5.02)	61.20 (0.00, 330.42)	< 0.001
CAC category				< 0.001
0	2671 (58.20)	2286 (70.99)	385 (28.12)
1-100	948 (20.66)	566 (17.58)	382 (27.90)
101-300	448 (9.76)	203 (6.30)	245 (17.90)
> 300	522 (11.38)	165 (5.12)	357 (26.08)

T2DM: Type 2 diabetes mellitus; HDL: High-density lipoprotein; LDL: Low-density lipoprotein; BMD: Bone mineral density; EAT: Epicardial adipose tissue; HU: Hounsfield unit; CACS: Coronary artery calcium score; CT: Computed tomography; BMI: Body mass index; CAC: Coronary artery calcification.

Table 2 Baseline characteristics of patients with type 2 diabetes mellitus stratified by duration, n (%)/median (interquartile range)

Variables	Short-duration	Intermediate-duration	Long-duration	P value
n	355	311	703
Baseline characteristic
Age (years)	57.00 (49.00, 64.00)	59.00 (52.00, 67.00)	61.00 (55.00, 69.00)	< 0.001
BMI (kg/m2)	24.09 (21.60, 26.26)	24.37 (22.03, 26.66)	23.81 (21.88, 26.10)	0.190
Male sex	223 (62.82)	214 (68.81)	472 (67.14)	0.220
Smoke	84 (23.66)	72 (23.15)	140 (19.91)	0.285
Alcohol	38 (10.70)	41 (13.18)	87 (12.38)	0.594
Hypertension	273 (76.90)	242 (77.81)	614 (87.34)	< 0.001
Dyslipidemia	256 (72.11)	206 (66.24)	490 (69.70)	0.257
Laboratory findings
HDL-cholesterol (mmol/L)	0.98 (0.79, 1.28)	0.96 (0.78, 1.21)	0.94 (0.78, 1.16)	0.084
LDL-cholesterol (mmol/L)	2.53 (1.86, 3.43)	2.47 (1.79, 3.00)	2.23 (1.68, 2.97)	< 0.001
Total cholesterol (mmol/L)	4.40 (3.45, 5.70)	4.11 (3.43, 5.10)	3.91 (3.20, 4.86)	< 0.001
Triglyceride (mmol/L)	1.89 (1.21, 3.21)	1.66 (1.14, 2.40)	1.63 (1.08, 2.46)	0.001
HbA1c (%)	7.00 (6.30, 7.10)	7.00 (6.30, 7.00)	6.90 (6.35, 7.10)	0.008
Fast glucose (mmol/L)	7.49 (5.97, 10.52)	7.65 (6.04, 10.56)	8.51 (6.25, 11.72)	0.002
CT findings
BMD (mg/cm3)	171.70 (148.95, 191.93)	168.83 (145.90, 185.79)	166.44 (141.91, 186.12)	0.013
EAT volume (cm3)	157.95 (107.31, 214.17)	167.29 (114.66, 220.84)	160.16 (110.63, 214.58)	0.491
EAT density (HU)	-76.84 (-83.17, -70.48)	-74.91 (-81.98, -69.52)	-74.36 (-80.03, -69.10)	< 0.001
CACS	12.87 (0.00, 145.79)	34.09 (0.00, 260.27)	116.96 (7.63, 496.13)	< 0.001
CAC category				< 0.001
0	139 (39.15)	99 (31.83)	147 (20.91)
1-100	111 (31.27)	89 (28.62)	182 (25.89)
101-300	49 (13.80)	52 (16.72)	144 (20.48)
> 300	56 (15.77)	71 (22.83)	230 (32.72)

HDL: High-density lipoprotein; LDL: Low-density lipoprotein; BMD: Bone mineral density; EAT: Epicardial adipose tissue; HU: Hounsfield unit; CACS: Coronary artery calcium score; CT: Computed tomography; BMI: Body mass index; CAC: Coronary artery calcification; HbA1c: Glycated hemoglobin.

Table 3 Comparison between non-type 2 diabetes mellitus patients and type 2 diabetes mellitus patients with different durations after matching, n (%)/median (interquartile range)

Variables	Non-T2DM vs short-duration T2DM		P value	Non-T2DM vs intermediate-duration T2DM		P value	Non-T2DM vs long-duration T2DM		P value
	Non-T2DM	Short-duration T2DM		Non-T2DM	Intermediate-duration T2DM		Non-T2DM	Long-duration T2DM
n	355	355		308	308		664	664
Age (years)	57.00 (50.00, 64.00)	57.00 (49.00, 64.00)	0.937	59.00 (51.75, 66.00)	59.00 (52.00, 67.00)	0.746	59.00 (54.00, 67.00)	60.00 (54.00, 68.00)	0.133
BMI (kg/m2)	24.02 (21.64, 26.13)	24.09 (21.60, 26.26)	0.874	24.22 (22.35, 26.45)	24.32 (22.03, 26.68)	0.878	24.12 (22.20, 26.23)	23.88 (21.88, 26.18)	0.218
Male sex	203 (57.18)	223 (62.82)	0.125	221 (71.75)	211 (68.51)	0.379	457 (68.83)	447 (67.32)	0.556
Smoke	75 (21.13)	84 (23.66)	0.418	84 (27.27)	71 (23.05)	0.227	137 (20.63)	133 (20.03)	0.785
Alcohol	37 (10.42)	38 (10.70)	0.903	52 (16.88)	41 (13.31)	0.216	82 (12.35)	86 (12.95)	0.741
Hypertension	274 (77.18)	273 (76.90)	0.929	239 (77.60)	239 (77.60)	1.000	574 (86.45)	575 (86.60)	0.936
Dyslipidemia	263 (74.08)	256 (72.11)	0.554	213 (69.16)	203 (65.91)	0.390	458 (68.98)	452 (68.07)	0.723
Fast glucose (mmol/L)	5.25 (4.85, 5.78)	7.49 (5.97, 10.52)	< 0.001	5.24 (4.86, 5.79)	7.66 (6.02, 10.56)	< 0.001	5.24 (4.84, 5.79)	8.57 (6.26, 11.71)	< 0.001
CACS	0.00 (0.00, 27.55)	12.87 (0.00, 145.79)	< 0.001	0.00 (0.00, 34.71)	34.00 (0.00, 257.59)	< 0.001	0.00 (0.00, 66.40)	113.28 (7.31, 470.36)	< 0.001
CAC category			< 0.001			< 0.001			< 0.001
0	212 (59.72)	139 (39.15)		180 (58.44)	98 (31.82)		357 (53.77)	143 (21.54)
1-100	87 (24.51)	111 (31.27)		72 (23.38)	89 (28.90)		164 (24.70)	174 (26.20)
101-300	32 (9.01)	49 (13.80)		33 (10.71)	51 (16.56)		67 (10.09)	139 (20.93)
> 300	24 (6.76)	56 (15.77)		23 (7.47)	70 (22.73)		76 (11.45)	208 (31.33)
BMD (mg/cm3)	167.53 (145.37, 193.04)	171.70 (148.95, 191.93)	0.430	169.01 (145.01, 189.85)	169.32 (146.29, 185.90)	0.874	163.40 (141.82, 185.09)	166.87 (142.84, 186.62)	0.722
EAT volume (cm3)	149.17 (106.21, 202.46)	157.95 (107.31, 214.17)	0.338	166.60 (126.41, 218.08)	166.26 (114.52, 219.02)	0.495	162.74 (120.21, 213.48)	158.94 (109.21, 213.74)	0.144
EAT density (HU)	-78.71 (-83.49, -74.02)	-76.84 (-83.17, -70.48)	0.006	-80.56 (-85.52, -75.47)	-74.88 (-81.88, -69.48)	< 0.001	-79.95 (-84.58, -75.21)	-74.17 (-80.02, -69.11)	< 0.001

T2DM: Type 2 diabetes mellitus; BMI: Body mass index; CACS: Coronary artery calcium score; CAC: Coronary artery calcification; BMD: Bone mineral density; EAT: Epicardial adipose tissue; HU: Hounsfield unit.

Table 4 Comparison between type 2 diabetes mellitus patients with different durations after matching, n (%)/median (interquartile range)

Variables	Short-duration vs intermediate-duration		P value	Short-duration vs long-duration		P value	Intermediate-duration vs long-duration		P value
	Short-duration	Intermediate-duration		Short-duration	Long-duration		Intermediate-duration	Long-duration
n	267	267		310	310		305	305
Age (years)	58.00 (51.00, 66.00)	58.00 (52.00, 65.00)	0.878	57.00 (50.00, 65.00)	59.00 (51.25, 66.00)	0.114	59.00 (52.00, 67.00)	60.00 (54.00, 68.00)	0.082
BMI (kg/m2)	24.04 (21.51, 26.09)	24.37 (22.01, 26.69)	0.148	24.14 (21.54, 25.96)	23.88 (21.89, 26.13)	0.785	24.38 (22.03, 26.67)	23.74 (21.89, 26.12)	0.147
Male sex	181 (67.79)	178 (66.67)	0.782	196 (63.23)	202 (65.16)	0.615	209 (68.52)	201 (65.90)	0.490
Smoke	61 (22.85)	63 (23.60)	0.838	67 (21.61)	74 (23.87)	0.502	69 (22.62)	66 (21.64)	0.770
Alcohol	27 (10.11)	32 (11.99)	0.490	35 (11.29)	42 (13.55)	0.394	39 (12.79)	37 (12.13)	0.806
Hypertension	208 (77.90)	206 (77.15)	0.836	246 (79.35)	251 (80.97)	0.615	241 (79.02)	250 (81.97)	0.358
Dyslipidemia	188 (70.41)	173 (64.79)	0.165	220 (70.97)	222 (71.61)	0.859	200 (65.57)	209 (68.52)	0.438
Fast glucose (mmol/L)	7.49 (6.04, 10.59)	7.66 (6.04, 10.61)	0.621	7.43 (5.97, 10.43)	8.61 (6.52, 11.93)	< 0.001	7.65 (6.04, 10.65)	8.72 (6.52, 11.22)	0.015
HbA1c (%)	7.00 (6.30, 7.10)	7.00 (6.35, 7.00)	0.289	7.00 (6.30, 7.10)	7.00 (6.40, 7.27)	0.775	7.00 (6.30, 7.00)	6.90 (6.40, 7.10)	0.574
CACS	21.14 (0.00, 161.95)	32.04 (0.00, 213.55)	0.426	18.96 (0.00, 164.64)	79.28 (0.00, 326.17)	< 0.001	35.05 (0.00, 265.64)	121.49 (7.85, 492.69)	< 0.001
CAC category			0.697			0.001			0.003
0	96 (35.96)	88 (32.96)		112 (36.13)	84 (27.10)		94 (30.82)	61 (20.00)
1-100	85 (31.84)	80 (29.96)		99 (31.94)	79 (25.48)		89 (29.18)	79 (25.90)
101-300	39 (14.61)	46 (17.23)		46 (14.84)	62 (20.00)		52 (17.05)	67 (21.97)
> 300	47 (17.60)	53 (19.85)		53 (17.10)	85 (27.42)		70 (22.95)	98 (32.13)
BMD (mg/cm3)	166.10 (147.47, 190.49)	170.11 (147.51, 187.26)	0.900	171.64 (149.81, 191.01)	170.02 (144.57, 188.12)	0.222	168.83 (145.61, 185.70)	167.88 (141.91, 186.09)	0.445
EAT volume (cm3)	155.47 (105.92, 220.46)	159.70 (113.23, 210.34)	0.969	156.71 (107.58, 215.17)	151.50 (104.02, 210.74)	0.508	168.09 (115.08, 221.18)	157.13 (110.40, 212.37)	0.276
EAT density (HU)	-75.93 (-82.31, -69.26)	-75.20 (-82.29, -69.59)	0.833	-76.30 (-83.13, -69.80)	-74.38 (-79.66, -69.31)	0.004	-74.95 (-81.93, -69.51)	-74.64 (-79.70, -69.28)	0.204

BMI: Body mass index; HbA1c: Glycated hemoglobin; CACS: Coronary artery calcium score; CAC: Coronary artery calcification; BMD: Bone mineral density; EAT: Epicardial adipose tissue; HU: Hounsfield unit.

Table 5 Multivariate linear regression analysis of type 2 diabetes mellitus with bone mineral density, epicardial adipose tissue volume, and epicardial adipose tissue density

Model	BMD		EAT volume		EAT density
	β (95%CI)	P value	β (95%CI)	P value	β (95%CI)	P value
Model 1	-9.579 (-11.617 to -7.542)	< 0.001	24.122 (19.546-28.697)	< 0.001	2.255 (1.711-2.799)	< 0.001
Model 2	1.411 (-0.411 to 3.233)	0.129	4.304 (-0.070 to 8.679)	0.054	3.611 (3.055-4.167)	< 0.001
Model 3	0.506 (-1.477 to 2.489)	0.617	-3.363 (-8.056 to 1.331)	0.16	4.131 (3.528-4.733)	< 0.001

Model 1: Unadjusted. Model 2: Adjusted for age and sex. Model 3: Further adjusted for smoking status, alcohol consumption, hypertension, dyslipidemia, and body mass index. BMD: Bone mineral density; EAT: Epicardial adipose tissue.

Table 6 Multivariate logistic regression analysis of type 2 diabetes mellitus with severe coronary artery calcification

Variables	SCAC
	OR (95%CI)	P value
Model 1	6.532 (5.360-7.960)	< 0.001
Model 2	4.294 (3.487-5.288)	< 0.001
Model 3	3.656 (2.903-4.604)	< 0.001

Model 1: Unadjusted. Model 2: Adjusted for age and sex. Model 3: Further adjusted for smoking status, alcohol consumption, hypertension, dyslipidemia, and body mass index. SCAC: Severe coronary artery calcification; OR: Odds ratio.

Table 7 Threshold effect analysis of the relationship between bone mineral density and epicardial adipose tissue density

Model	Threshold	β (95%CI)	P value
Model 1: Standard linear regression	-	-0.06 (-0.07 to -0.06)	< 0.001
Model 2: Piecewise linear regression	-	-	-
Threshold	174.91	-	-
< 174.91	-	-0.12 (-0.13 to -0.10)	< 0.001
≥ 174.91	-	0.02 (-0.00 to 0.04)	0.060
Likelihood ratio test P	-	-	< 0.001

Model 1: Simple linear regression. Model 2: Piecewise linear regression fitted after threshold identification using the maximum likelihood method. The likelihood ratio test compares model 2 with model 1, P value < 0.05 indicates a significant threshold effect.