Impact of fasting glucose on electrocardiographic left ventricular hypertrophy in an elderly general population

Figures & data

Table Ia. Characteristics of the male patients (with a history of cardiovascular event or cardiovascular, antidiabetic or lipid-lowering medical treatment).

Baseline evaluation	Missing	All (n = 716)	NFG (n = 166)	IFG (n = 179)	New-onset or established DM (n = 371)	p Value for difference
Age (years)	0	67 ± 6	67 ± 6	66 ± 6	67 ± 6	0.11
Systolic blood pressure (mmHg)	0	148 ± 19	144 ± 18	149 ± 18	150 ± 20	0.003
Diastolic blood pressure (mmHg)	0	84 ± 10	83 ± 11	86 ± 10	84 ± 10	0.04
Heart rate (beats/min)	2	70 ± 12	68 ± 12	69 ± 13	72 ± 12	0.001
Body mass index (kg/m^2)	1	28.9 ± 4.0	27.1 ± 3.3	28.6 ± 3.5	29.1 ± 4.2	< 0.001
Waist/hip ratio	1	1.00 ± 0.06	0.97 ± 0.05	0.99 ± 0.06	1.01 ± 0.06	< 0.001
Active smoking, n	0	98 (14)	28 (17)	26 (15)	44 (12)	0.28
Blood tests
Triglycerides (mmol/l)	0	1.5 ± 0.9	1.2 ± 0.6	1.4 ± 0.7	1.8 ± 1.0	< 0.001
Total cholesterol (mmol/l)	0	4.9 ± 1.0	5.1 ± 1.0	5.0 ± 1.0	4.8 ± 1.0	0.03
LDL cholesterol (mmol/l)	16	3.1 ± 0.9	3.2 ± 0.9	3.2 ± 0.9	2.9 ± 0.9	0.001
HDL cholesterol (mmol/l)	0	1.2 ± 0.3	1.3 ± 0.4	1.2 ± 0.3	1.1 ± 0.3	< 0.001
LDL/HDL ratio	16	2.7 ± 1.0	2.7 ± 1.1	2.7 ± 1.0	2.7 ± 1.0	0.92
Glucose (mmol/l)	0	7.4 ± 2.3	5.5 ± 0.4	6.4 ± 0.3	8.7 ± 2.4	NA
NT-proBNP (pg/ml)	4	14 (7–32)	15 (7–37)	14 (6–35)	14 (7–31)	0.63
hs-TnT (ng/l)	7	13 ± 11	12 ± 9	11 ± 8	14 ± 12	0.001
Electrocardiography
SL (mm)	0	21 ± 7	23 ± 7	22 ± 7	20 ± 7	< 0.001
CP (mm × ms)	0	1605 ± 828	1623 ± 919	1583 ± 767	1607 ± 814	0.90
LVH, n	0	81 (11)	19 (11)	17 (9.5)	45 (12)	0.66
LVH by SL, n	0	12 (1.7)	5 (3.0)	3 (1.7)	4 (1.1)	0.224
LVH by CP, n	0	75 (11)	17 (10)	15 (8.4)	43 (12)	0.51
Medical history
Previous MACE, or HF, n	10	161 (23)	39 (24)	39 (22)	83 (23)	0.94
– as above, or AF, n	10	194 (28)	48 (29)	53 (30)	93 (26)	0.49
– as above, or AF, or stroke, n	10	232 (33)	59 (36)	60 (34)	113 (31)	0.53
Cardiovascular medical treatment, n	0	597 (83)	140 (84)	164 (92)	293 (79)	0.001
Antidiabetic medical treatment, n	0	241 (34)	0 (0.0)	0 (0.0)	241 (65)	NA
Lipid-lowering medical treatment, n	0	338 (47)	73 (44)	84 (47)	181 (49)	0.59

Values are n (%) for categorical variables, whereas continuous variables are presented as mean ± standard deviation or as median (interquartile range).

NFG, normal fasting glucose; IFG, impaired fasting glucose; DM, diabetes mellitus; n, number; LDL, low-density lipoprotein; HDL, high-density lipoprotein; NA, not applicable; NT-proBNP, N-terminal prohormone of brain natriuretic peptide; hs-TnT, high-sensitivity cardiac troponin T; SL, Sokolow–Lyon voltage combination; CP, Cornell voltage–duration product; LVH, left ventricular hypertrophy; MACE, major adverse cardiac events (acute myocardial infarction, percutaneous intervention or coronary artery bypass graft); HF, heart failure; AF, atrial fibrillation or flutter.

Table Ib. Characteristics of the female patients (with a history of cardiovascular event or cardiovascular, antidiabetic or lipid-lowering medical treatment).

Baseline evaluation	Missing	All (n = 291)	NFG (n = 110)	IFG (n = 64)	New-onset or established DM (n = 116)	p Value for difference
Age (years)	0	70 ± 5	69 ± 5	70 ± 5	70 ± 5	0.29
Systolic blood pressure (mmHg)	0	145 ± 20	143 ± 20	144 ± 20	148 ± 20	0.14
Diastolic blood pressure (mmHg)	0	82 ± 10	81 ± 11	83 ± 11	81 ± 9	0.32
Heart rate (beats/min)	4	72 ± 12	70 ± 12	71 ± 12	73 ± 12	0.08
Body mass index (kg/m^2)	1	29.2 ± 5.3	27.1 ± 4.2	30.2 ± 5.5	30.7 ± 5.6	< 0.001
Waist/hip ratio	1	0.88 ± 0.09	0.84 ± 0.08	0.88 ± 0.07	0.91 ± 0.09	< 0.001
Active smoking, n	0	25 (8.6)	8 (7. 3)	9 (14)	8 (6.9)	0.21
Blood tests
Triglycerides (mmol/l)	1	1.5 ± 0.8	1.3 ± 0.9	1.5 ± 0.6	1.6 ± 0.7	0.02
Total cholesterol (mmol/l)	1	5.5 ± 1.0	5.7 ± 1.0	5.6 ± 1.2	5.2 ± 1.0	0.001
LDL cholesterol (mmol/l)	6	3.4 ± 1.0	3.8 ± 0.9	3.4 ± 1.1	3.1 ± 0.9	0.001
HDL cholesterol (mmol/l	1	1.5 ± 0.5	1.6 ± 0.5	1.5 ± 0.5	1.4 ± 0.4	0.007
LDL/HDL ratio	6	2.4 ± 1.0	2.4 ± 0.9	2.6 ± 1.1	2.4 ± 1.0	0.56
Glucose (mmol/l)	1	6.8 ± 2.0	5.2 ± 0.5	6.4 ± 0.3	8.5 ± 2.2	NA
NT-proBNP (pg/ml)	4	18 (9–32)	19 (11–33)	19 (9–34)	15 (8–32)	0.97
hs-TnT (ng/l)	4	10 ± 9	9 ± 8	10 ± 9	11 ± 9	0.26
Electrocardiography
SL (mm)	0	20 ± 6	21 ± 6	1 ± 6	20 ± 7	0.16
CP (mm × ms)	0	2108 ± 894	2108 ± 978	2450 ± 1018	2092 ± 730	0.92
LVH, n	0	67 (23)	27 (25)	14 (22)	26 (24)	0.90
LVH by SL, n	0	4 (1.4)	1 (0.9)	1 (1.6)	2 (1.7)	1.00
LVH by CP, n	0	63 (22)	26 (24)	13 (20)	24 (21)	0.83
Medical history
Previous MACE, or HF, n	1	32 (11)	9 (8.2)	11 (17)	12 (10)	0.18
– as above, or AF, n	1	49 (17)	17 (16)	16 (25)	16 (14)	0.14
– as above, or AF, or stroke, n	1	57 (20)	21 (19)	16 (25)	20 (17)	0.46
Cardiovascular medical treatment, n	0	248 (85)	99 (90)	57 (89)	91 (78)	0.03
Anti-diabetic medical treatment, n	0	81 (28)	0 (0.0)	0 (0.0)	81 (70)	NA
Lipid-lowering medical treatment, n	0	113 (39)	29 (26)	34 (53)	49 (42)	0.001

Values are n (%) for categorical variables, whereas continuous variables are presented as mean ± standard deviation or as median (interquartile range).

NFG, normal fasting glucose; IFG, impaired fasting glucose; DM, diabetes mellitus; n, number; LDL, low-density lipoprotein; HDL, high-density lipoprotein; NA, not applicable; NT-proBNP, N-terminal prohormone of brain natriuretic peptide; hs-TnT, high-sensitivity cardiac troponin T; SL, Sokolow–Lyon voltage combination; CP, Cornell voltage–duration product; LVH, left ventricular hypertrophy; MACE, major adverse cardiac events (acute myocardial infarction, percutaneous intervention or coronary artery bypass graft); HF, heart failure; AF, atrial fibrillation or flutter.

Table IIa. Characteristics of the healthy male subjects (without a history of cardiovascular event or cardiovascular, antidiabetic or lipid-lowering medical treatment).

Baseline evaluation	Missing	All (n = 529)	NFG (n = 223)	IFG (n = 139)	New-onset DM (n = 105)	p Value for difference
Age (years)	0	64 ± 6	64 ± 6	64 ± 5	65 ± 5	0.075
Systolic blood pressure (mmHg)	0	148 ± 20	143 ± 17	150 ± 21	156 ± 23	< 0.001
Diastolic blood pressure (mmHg)	0	86 ± 10	84 ± 10	88 ± 10	89 ± 11	< 0.001
Heart rate (beats/min)	2	73 ± 13	69 ± 12	74 ± 12	76 ± 14	< 0.001
Body mass index (kg/m^2)	2	27.3 ± 3.6	26.1 ± 3.2	27.6 ± 3.3	28.4 ± 4.3	< 0.001
Waist/hip ratio	0	0.97 ± 0.06	0.95 ± 0.05	0.97 ± 0.06	1.00 ± 0.06	< 0.001
Active smoking, n	0	107 (20)	43 (19)	43 (21)	21 (20)	0.86
Blood tests
Triglycerides (mmol/l)	0	1.5 ± 1.2	1.2 ± 0.7	1.5 ± 1.0	2.1 ± 1.9	< 0.001
Total cholesterol (mmol/l)	0	5.8 ± 1.0	5.8 ± 0.9	5.8 ± 1.1	5.9 ± 1.2	0.41
LDL cholesterol (mmol/l)	18	3.9 ± 0.9	3.9 ± 0.8	3.9 ± 0.9	3.9 ± 1.0	0.93
HDL cholesterol (mmol/l)	0	1.3 ± 0.3	1.4 ± 0.4	1.3 ± 0.3	1.1 ± 0.3	< 0.001
LDL/HDL ratio	18	3.2 ± 1.2	3.1 ± 1.1	3.2 ± 1.2	3.6 ± 1.2	0.001
Glucose (mmol/l)	0	6.5 ± 1.7	5.4 ± 0.5	6.4 ± 0.2	8.9 ± 2.6	NA
NT-proBNP (pg/ml)	4	7 (4–14)	7 (5–14)	4 (4–12)	8 (5–16)	0.01
hs-TnT (ng/l)	2	9 ± 5	8 ± 5	8 ± 5	10 ± 7	0.004
Electrocardiography
SL (mm)	0	22 ± 7	24 ± 7	22 ± 7	21 ± 6	0.072
CP (mm × ms)	0	1428 ± 741	1341 ± 700	1447 ± 776	1575 ± 740	0.02
LVH, n	0	50 (9.5)	17 (7.6)	22 (11)	11 (11)	0.47
LVH by SL, n	0	9 (1.7)	5 (2.2)	4 (2.0)	0 (0.0)	0.34
LVH by CP, n	0	45 (8.5)	13 (5.8)	21 (10)	11 (11)	0.17

Values are n (%) for categorical variables, whereas continuous variables are presented as mean ± standard deviation or as median (interquartile range).

NFG, normal fasting glucose; IFG, impaired fasting glucose; DM, diabetes mellitus; n, number; LDL, low-density lipoprotein; HDL, high-density lipoprotein; NA, not applicable; NT-proBNP, N-terminal prohormone of brain natriuretic peptide; hs-TnT, high-sensitivity cardiac troponin T; SL, Sokolow–Lyon voltage combination; CP, Cornell voltage–duration product; LVH, left ventricular hypertrophy.

Table IIb. Characteristics of the healthy female subjects (without a history of cardiovascular event or cardiovascular, anti-diabetic or lipid-lowering medical treatment).

Baseline evaluation	Missing	All (n = 223)	NFG (n = 149)	IFG (n = 43)	New-onset DM (n = 31)	p Value for difference
Age (years)	0	68 ± 5	68 ± 5	67 ± 6	70.6 ± 5	0.01
Systolic blood pressure (mmHg)	0	144 ± 20	143 ± 19	145 ± 20	152 ± 21	0.070
Diastolic blood pressure (mmHg)	0	84 ± 10	83 ± 10	83 ± 10	87 ± 11	0.12
Heart rate (beats/min)	2	75 ± 11	74 ± 11	76 ± 13	81 ± 12	0.009
Body mass index (kg/m^2)	0	27.5 ± 4.5	26.8 ± 3.9	27.4 ± 4.3	31.1 ± 5.3	< 0.001
Waist/hip ratio	0	0.85 ± 0.08	0.84 ± 0.07	0.84 ± 0.07	0.91 ± 0.07	< 0.001
Active smoking, n	0	26 (12)	18 (12)	5 (12)	3 (10)	0.93
Blood tests
Triglycerides (mmol/l)	0	1.2 ± 0.6	1.1 ± 0.5	1.2 ± 0.5	1.7 ± 0.8	< 0.001
Total cholesterol (mmol/l)	0	6.2 ± 1.0	6.2 ± 1.0	6.1 ± 0.9	6.3 ± 1.0	0.48
LDL cholesterol (mmol/l)	0	4.0 ± 0.9	4.0 ± 0.9	3.9 ± 0.8	4.2 ± 0.9	0.39
HDL cholesterol (mmol/l)	0	1.6 ± 0.5	1.6 ± 0.4	1.6 ± 0.5	1.4 ± 0.5	0.02
LDL/HDL ratio	0	2.7 ± 1.0	2.6 ± 0.9	2.4 ± 1.1	3.3 ± 1.1	0.002
Glucose (mmol/l)	0	6.0 ± 1.7	5.3 ± 0.4	6.3 ± 0.2	9.0 ± 3.0	NA
NT-proBNP (pg/ml)	3	13 (8–21)	14 (9–22)	10 (7–15)	11 (7–21)	0.02
hs-TnT (ng/l)	0	7.3 ± 6.4	7 ± 3	7 ± 12	10 ± 8	0.03
Electrocardiography
SL (mm)	0	21 ± 7	21 ± 7	20 ± 8	20 ± 6	0.82
CP (mm × ms)	0	1879 ± 657	1848 ± 668	1841 ± 464	2128 ± 787	0.075
LVH, n	0	37 (17)	23 (15)	5 (12)	9 (29)	0.12
LVH by SL, n	0	4 (1.8)	4 (2.7)	0 (0.0)	0 (0.0)	0.77
LVH by CP, n	0	35 (16)	21 (14)	5 (12)	9 (29)	0.12

Values are n (%) for categorical variables, whereas continuous variables are presented as mean ± standard deviation or as median (interquartile range).

NFG, normal fasting glucose; IFG, impaired fasting glucose; DM, diabetes mellitus; n, number; LDL, low-density lipoprotein; HDL, high-density lipoprotein; NA, not applicable; NT-proBNP, N-terminal prohormone of brain natriuretic peptide; hs-TnT, high-sensitivity cardiac troponin T; SL, Sokolow–Lyon voltage combination; CP, Cornell voltage–duration product; LVH, left ventricular hypertrophy.

Figure 1. Differences between electrocardiographic markers of left ventricular hypertrophy among fasting plasma glucose groups. p, p value for difference between the groups analyzed using one-way analysis of variance; n, number; NFG, normal fasting glucose; IFG, impaired fasting glucose; DM, diabetes mellitus.

Figure 2. Odds ratios (×) and 95% confidence intervals for the independent explanatory factors for the presence of electrocardiographically identified left ventricular hypertrophy in healthy males.

Table III. Independent explanatory factors for the presence of electrocardiographically identified left ventricular hypertrophy.

	All patients (n = 1007)			Male patients (n = 716)			Female patients (n = 291)			All healthy subjects (n = 752)			Healthy males (n = 529)			Healthy females (n = 223)
Risk factor	OR	95% CI	p	OR	95% CI	p	OR	95% CI	p	OR	95% CI	p	OR	95% CI	p	OR	95% CI	p
Gender (female)	2.131	1.449–3.134	< 0.001	NA			NA			1.834†	1.095–3.073	0.021	NA			NA
Age	1.067	1.030–1.106	< 0.001	1.074	1.029–1.120	0.001	NS			1.060	1.014–1.107	0.010	1.063	1.007–1.122	0.027	NS
SBP	NS			1.017†	1.005–1.030	0.007	NS			1.020	1.009–1.032	< 0.001	1.019	1.005–1.033	0.009	1.024†	1.006–1.042	0.008
HR	0.986†	0.971–1.001	0.067	NS			NS			0.972	0.952–0.993	0.008	0.970†	0.945–0.996	0.025	NS
FPG	NS			NS			NS			1.107	0.988–1.241	0.080	1.152	1.005–1.321	0.042	NS
Lipid-lowering medical treatment	NS			1.562†	0.945–2.582	0.082	NS			NS			NS			NS
Previous CV event	NS			1.743†	1.041–2.920	0.035	NS			NS			NS			NS
LDL cholesterol	0.807	0.661–0.986	0.036	NS			0.775	0.577–1.041	0.091	NS			NS			NS
HDL cholesterol	NS			NS			0.558†	0.280–1.113	0.098	NS			NS			NS

n, number; OR, odds ratio; CI, confidence interval; p, p value; NA, not applicable; NS, not significant; SBP, systolic blood pressure; HR, heart rate; FPG, fasting plasma glucose; CV, cardiovascular; LDL, low-density lipoprotein; HDL, high-density lipoprotein.

Backward selection was performed in the model after inclusion of univariately associated variables: gender, age, SBP, HR, active smoking, triglycerides, LDL cholesterol, HDL cholesterol, glucose, CV medical treatment and lipid-lowering medical treatment. FPG group and previous CV event were also included.

†Not significant when considering only the younger half of the population.

Table IV. Independent explanatory factors for Sokolow–Lyon voltage combination.

	All patients (n = 1007)		Male patients (n = 716)		Female patients (n = 291)		All healthy subjects (n = 752)		Healthy males (n = 529)		Healthy females (n = 223)
Risk factor	Std. beta	p	Std. beta	p	Std. beta	p	Std. beta	p	Std. beta	p	Std. beta	p
Gender (female)	–0.058^†	0.057	NA		NA		NS		NA		NA
SBP	0.212	< 0.001	0.232	< 0.001	0.155	0.007	0.205	< 0.001	0.200	< 0.001	0.224^†	0.001
HR	–0.125	< 0.001	–0.131	< 0.001	NS		–0.083	0.024	–0.107	0.015	NS
BMI	–0.239	< 0.001	–0.216	< 0.001	–0.277	< 0.001	− 0.217	< 0.001	–0.206	< 0.001	–0.246^†	< 0.001
LDL cholesterol	NS^†		NS		NS		NS		NS		–0.136^†	0.034
FPG group	–0.067^†	0.034	–0.113^†	0.002	NS		NS		NS		NS

n, number; Std. beta; standardized beta coefficient; p, p value; NA, not applicable; NS, not significant; SBP, systolic blood pressure; HR, heart rate; BMI, body mass index; LDL, low-density lipoprotein; FPG, fasting plasma glucose.

Backward selection was performed in the model after inclusion of univariately associated variables: gender, SBP, HR, BMI, LDL cholesterol, HDL cholesterol, glucose and antidiabetic medical treatment. FPG group and previous cardiovascular event were also included.

^†Not significant when considering only the younger half of the population.

Table V. Independent explanatory factors for Cornell voltage–duration product.

	All patients (n = 1007)		Male patients (n = 716)		Female patients (n = 291)		All healthy subjects (n = 752)		Healthy males (n = 529)		Healthy females (n = 223)
Risk factor	Std. beta	p	Std. beta	p	Std. beta	p	Std. beta	p	Std. beta	p	Std. beta	p
Gender (female)	0.232	< 0.001	NA		NA		0.253	< 0.001	NA		NA
Age	0.130	< 0.001	0.146	< 0.001	NS		0.151	< 0.001	0.146	0.001	0.188	0.005
SBP	0.065	0.033	0.119	0.002	NS		0.139	< 0.001	0.152	0.001	0.143	0.032
HR	–0.053^†	0.084	NS		NS		–0.097^†	0.007	–0.124^†	0.006	NS
BMI	NS		NS		NS		0.092	0.012	0.147	0.001	NS
Active smoking	0.064^†	0.037	0.107^†	0.004	NS		0.064	0.067	NS		NS
Triglycerides	0.055^†	0.073	0.071	0.057	NS		NS		–0.108	0.019	NS
Total cholesterol	NS		NS		–0.126	0.032	NS		NS		NS
Glucose	NS		NS		NS		NS		0.126	0.007	NS
CV medical treatment	NS		NS		0.116^†	0.049	NS		NS		NS
FPG group	NS		NS		NS		0.074	0.046	NS		NS
Previous CV event	NS		0.076^†	0.045	NS		NS		NS		NS

n, number; Std. beta; standardized beta coefficient; p, p value; NA, not applicable; SBP, systolic blood pressure; HR, heart rate; NS, not significant; BMI, body mass index; CV, cardiovascular; FPG, fasting plasma glucose.

Backward selection was performed in the model after inclusion of univariately associated variables: gender, age, SBP, HR, BMI, active smoking, triglycerides, total cholesterol, glucose and CV medical treatment. FPG group and previous CV event were also included.

^†Not significant when considering only the younger half of the population.