Research Article

Free Triiodothyronine Concentrations Are Inversely Associated with Microalbuminuria

Table 1

General characteristics of the study population.

FT3 quartiles (pmol/L)
Quartile 1Quartile 2Quartile 3Quartile 4 for trend
() () () ()

Male275 (32.8)293 (34.8)329 (38.9)439 (53.6)<0.0001
Age (years)63.6 ± 11.161.0 ± 10.160.1 ± 9.558.4 ± 8.3<0.0001
BMI (kg/m2)24.9 ± 3.725.3 ± 3.725.3 ± 3.825.7 ± 3.5<0.0001
Current smokers120 (14.3)154 (18.3)163 (19.3)251 (30.7)<0.0001
Current drinkers111 (13.2)125 (14.8)129 (15.3)160 (19.5)0.0006
Use of ACEI/ARB drugs33 (3.93)32 (3.80)31 (3.67)33 (4.03)0.98
SBP (mmHg)139.5 ± 23.5137.6 ± 22.2138.6 ± 21.2138.9 ± 20.40.77
DBP (mmHg)76.3 ± 10.177.8 ± 10.278.6 ± 9.681.0 ± 10.5<0.0001
FPG (mmol/L)5.2 (4.7–6.1)5.2 (4.8–6.1)5.2 (4.8–5.8)5.3 (4.8–6.0)0.08
OGTT-2 h PG (mmol/L)8.5 (6.3–14.4)7.8 (6.1–12.5)7.6 (6.1–11.4)7.7 (6.3–11.4)<0.0001
Triglycerides (mmol/L)1.28 (0.89–1.89)1.40 (1.00–2.02)1.46 (1.01–2.14)1.61 (1.10–2.34)<0.0001
TC (mmol/L)5.07 ± 1.045.15 ± 0.985.21 ± 0.935.17 ± 0.990.02
HDL-C (mmol/L)1.37 ± 0.331.36 ± 0.291.37 ± 0.321.32 ± 0.290.01
LDL-C (mmol/L)2.34 ± 0.712.41 ± 0.702.39 ± 0.662.42 ± 0.680.03
FT3 (pmol/L)4.05 (3.84–4.18)4.45 (4.37–4.53)4.76 (4.68–4.85)5.18 (5.05–5.38)
FT4 (pmol/L)13.7 (12.7–14.9)14.1 (13.2–15.1)14.2 (13.3–15.3)14.8 (13.8–15.8)<0.0001
TSH (μIU/mL)1.59 (1.07–2.33)1.50 (1.02–2.18)1.44 (1.01–2.1601.35 (0.92–1.99)<0.0001
TPOAb (IU/mL)0.30 (0.17–0.74)0.31 (0.17–0.77)0.30 (0.16–0.72)0.34 (0.18–0.81)0.93
TgAb (IU/mL)1.09 (0.70–2.73)1.08 (0.70–2.95)1.02 (0.71–2.27)1.05 (0.72–2.25)0.08
eGFR (mL/min/1.73 m2)107.5 ± 28.6112.6 ± 24.4112.8 ± 24.9115.8 ± 22.9<0.0001
UACR (mg/g)6.08 (2.86–12.86)5.93 (2.70–12.39)5.93 (2.79–12.48)5.28 (2.65–12.12)0.03
Hs-CRP (mg/g)0.21 (0.05–1.13)0.18 (0.06–0.85)0.18 (0.07–0.61)0.24 (0.08–0.82)0.58

Data were means ± SD or medians (interquartile range) or numbers (proportions). BMI, body mass index; ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; SBP, systolic blood pressure; DBP, diastolic blood pressure; TC, total cholesterol; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein; FPG, fasting plasma glucose; OGTT-2 h PG, OGTT 2-hour plasma glucose; FT3, free triiodothyronine; FT4, free thyroxine; TSH, thyroid stimulating hormone; TPOAb, thyroid peroxidase antibody; TgAb, thyroglobulin antibody; eGFR, estimate glomerular filtration rate; UACR, urinary albumin-to-creatinine ratio.
FT3 quartiles were as follows: quartile 1, ≤4.28 pmol/L; quartile 2, 4.29–4.60 pmol/L; quartile 3, 4.61–4.93 pmol/L; quartile 4, >4.94 pmol/L.