The impact of testosterone replacement therapy on glycemic control, vascular function, and components of the metabolic syndrome in obese hypogonadal men with type 2 diabetes

Figures & data

Figure 1. HbA1c values in obese hypogonadal DM2 patients before and after one year of TRT or placebo (intra- and inter-group differences and corresponding p values shown in Table 1); HbA1c: glycated hemoglobin A1c (%), P: placebo group, T: testosterone group, time point T₀: before and T₁: after one year of study.

Table 1. Anthropometric and metabolic parameters in obese hypogonadal DM2 patients before in after one year of TRT or placebo.

Parameter	Period	Group P	Group T	Group delta
BMI (kg/m^2)	T0	32.63 ± 3.67	34.03 ± 4.37	p = .204
	T1	31.96 ± 3.73	33.25 ± 4.77	p = .270
	T1–T0 delta	−0.67 ± 0.87 p < .001	−0.80 ± 1.17 p = .001	p = .651
WC (cm)	T0	116.64 ± 4.96	116.48 ± 5.07	p = .903
	T1	115.46 ± 4.78	114.90 ± 5.49	p = .689
	T1–T0 delta	−1.19 ± 1.28 p < .001	−1.58 ± 1.64 p < .001	p = .328
FPG (mmol/l)	T0	9.60 ± 1.44	10.06 ± 1.44	p = .241
	T1	9.47 ± 1.31	8.83 ± 1.21	p = .064
	T1–T0 delta	−0.13 ± 0.73 p = .359	−1.23 ± 1.25 p < .001	p < .001
HbA1c (%)	T0	7.89 ± 0.77	8.12 ± 1.04	p = .358
	T1	7.65 ± 0.70	7.18 ± 0.81	p = .025
	T1–T0 delta	−0.24 ± 0.39 p = .004	−0.94 ± 0.88 p < .001	p < .001
Insulin (mE/L)	T0	24.89 ± 13.90	26.03 ± 15.86	p = .778
	T1	24.38 ± 12.82	17.51 ± 10.70	p = .035
	T1–T0 delta	−0.51 ± 4.48 p = .561	−8.52 ± 7.76 p < .001	p < .001
HOMA-IR	T0	10.70 ± 6.52	11.45 ± 7.34	p = .692
	T1	10.18 ± 5.60	6.81 ± 4.18	p = .014
	T1–T0 delta	−0.52 ± 2.07 p = .203	−4.64 ± 4.25 p < .001	p < .001
Total cholesterol (mmol/l)	T0	5.31 ± 0.97	5.31 ± 0.91	p = .978
	T1	4.89 ± 0.74	4.62 ± 0.63	p = .149
	T1–T0 delta	−0.42 ± 0.78 p = .010	−0.70 ± 0.57 p < .001	p = .136
LDL (mmol/l)	T0	2.80 ± 0.95	2.79 ± 0.77	p = .988
	T1	2.54 ± 0.54	2.70 ± 0.59	p = .313
	T1–T0 delta	−0.25 ± 0.85 p = .137	−0.09 ± 0.53 p = .358	p = .407
HDL (mmol/l)	T0	1.05 ± 0.32	1.01 ± 0.22	p = .581
	T1	1.07 ± 0.29	1.04 ± 0.21	p = .648
	T1–T0 delta	0.02 ± 0.21 p = .580	0.03 ± 0.22 p = .452	p = .865
TG (mmol/l)	T0	3.52 ± 3.15	2.86 ± 1.49	p = .324
	T1	3.02 ± 2.08	2.32 ± 1.02	p = .117
	T1–T0 delta	−0.50 ± 1.46 p = .089	−0.54 ± 1.40 p = .052	p = .912
Syst. BP (mmHg)	T0	138.15 ± 13.24	134.64 ± 10.71	p = .284
	T1	135.93 ± 16.99	138.79 ± 13.65	p = .493
	T1–T0 delta	−2.22 ± 15.71 p = .469	4.14 ± 14.99 p = .155	p = .130
Diast. BP (mmHg)	T0	78.89 ± 5.25	77.50 ± 5.85	p = .359
	T1	78.70 ± 10.43	78.14 ± 10.08	p = .840
	T1–T0 delta	−0.16 ± 10.61 p = .928	0.64 ± 10.80 p = .755	p = .775

Data presented as mean ± standard deviation. BMI: body mass index; Diast. BP: diastolic blood pressure; FPG: fasting plasma glucose; group P: placebo group; group T: testosterone group; HbA1c: glycated hemoglobin A1c; HDL: high-density lipoprotein cholesterol; HOMA-IR: homeostasis model assessment insulin resistance index; Insulin: fasting plasma insulin; LDL: low-density lipoprotein cholesterol; p: p values; Syst. BP: systolic blood pressure; TG: triglycerides; T₀: before and T₁: after one year of study; WC: waist circumference.

p values < .05 are displayed in bold.

Figure 2. HOMA-IR in obese hypogonadal DM2 patients before and after one year of TRT or placebo (intra- and inter-group differences and corresponding p values shown in Table 1); HOMA-IR (homeostasis model assessment insulin resistance index), P: placebo group, T: testosterone group, time point T₀: before and T₁: after one year of study.

Table 2. Testosterone levels in obese hypogonadal DM2 patients before and after one year of TRT or placebo.

Parameter	Period	Group P	Group T	P vs. T
Total T (nmol/l)	T0	7.96 ± 1.34	7.24 ± 1.97	p = .120
	T1	9.83 ± 1.51	17.04 ± 3.07	p < .001
	T1–T0 delta	1.87 ± 1.54 p < .001	9.80 ± 3.59 p < .001	p < .001
BT (nmol/l)	T0	4.61 ± 0.95	3.74 ± 0.97	p = .001
	T1	5.73 ± 0.89	9.50 ± 1.89	p < .001
	T1–T0 delta	1.12 ± 0.93 p < .001	5.76 ± 2.16 p < .001	p < .001
cFT (pmol/l)	T0	192.07 ± 44.13	155.54 ± 41.11	p = .002
	T1	242.00 ± 42.23	403.84 ± 90.34	p < .001
	T1–T0 delta	49.93 ± 40.67 p < .001	248.29 ± 99.45 p < .001	p < .001
SHBG (nmol/l)	T0	21.58 ± 6.28	26.89 ± 10.86	p = .031
	T1	21.68 ± 6.54	27.21 ± 8.66	p = .010
	T1–T0 delta	0.10 ± 4.80 p = .915	0.32 ± 9.04 p = .852	p = .910

Data presented as mean ± standard deviation. BT: bioavailable testosterone; cFT: calculated free testosterone; group P: placebo group; group T: testosterone group; p: p values; SHBG: sex hormone binding globulin; Total T: total testosterone; T₀: before and T₁: after one year of study.

p values < .05 are displayed in bold.

Figure 3. FMD in obese hypogonadal DM2 patients before and after one year of TRT or placebo (intra- and inter-group differences and corresponding p values shown in Table 3); FMD (flow mediated dilatation, %), P: placebo group, T: testosterone group, time point T₀: before and T₁: after one year of study.

Table 3. FMD and IMT results in obese hypogonadal DM2 patients before and after one year of TRT or placebo.

Parameter	Period	Group P	Group T	P vs. T
FMD (%)	T0	3.84 ± 2.14	4.68 ± 2.81	p = .221
	T1	3.76 ± 2.41	7.07 ± 3.37	p < .001
	T1–T0 delta	−0.08 ± 3.33 p = .904	2.40 ± 4.16 p = .005	p = .019
NMD (%)	T0	15.81 ± 5.48	16.13 ± 5.20	p = .825
	T1	15.43 ± 6.65	17.25 ± 5.90	p = .287
	T1–T0 delta	−0.38 ± 6.80 p = .774	1.12 ± 6.81 p = .390	p = .416
FMD/NMD	T0	0.28 ± 0.19	0.31 ± 0.21	p = .594
	T1	0.26 ± 0.19	0.43 ± 0.21	p = 0.002
	T1–T0 delta	−0.02 ± 0.28 p = .716	0.12 ± 0.24 p = .013	p = .047
IMT (mm)	T0	0.83 ± 0.10	0.89 ± 0.12	p = .044
	T1	0.78 ± 0.06	0.79 ± 0.09	p = .603
	T1–T0 delta	−0.05 ± 0.09 p = .006	−0.10 ± 0.06 p < .001	p = .025

Data presented as mean ± standard deviation. FMD: flow-mediated dilatation; NMD: nitroglycerine-mediated dilatation; FMD/NMD ratio; IMT: intima media thickness; group P: placebo group; group T: testosterone group; p: p values; T₀: before and T₁: after one year of study.

p values < .05 are displayed in bold.