Correlation of gut microbiota metabolite trimethylamine N-oxide with inflammatory levels and osteoporosis in patients with diabetic nephropathy

Table 1 The results of the statistical comparison of general data between the two groups of patients, n (%)

	DN group (n = 115)	T2DM group (n = 115)	t/χ2	P value
Age (years old)	70.32 ± 7.41	68.88 ± 8.29	1.468	0.144
Sex			1.430	0.232
Male (cases)	69 (60.00)	60 (52.17)
Female (cases)	46 (40.00)	55 (47.83)
BMI (kg/m2)	24.40 ± 2.15	24.21 ± 2.43	0.630	0.529
Smoking (cases)	43 (37.39)	37 (32.17)	0.690	0.406
Drinking (cases)	39 (33.91)	47 (40.87)	1.189	0.276
Hypertension (cases)	65 (56.52)	73 (63.48)	1.159	0.282
Hyperlipidemia (cases)	79 (68.70)	84 (73.04)	0.527	0.468
Duration of diabetes (years)	12.64 ± 3.91	9.57 ± 2.85	6.896	0.000
eGFR (mL/min/1.73 m2)	48.52 ± 9.77	78.92 ± 14.65	-23.227	0.000
Fasting blood glucose (mmol/L)	7.59 ± 1.85	6.97 ± 1.88	2.507	0.013
Fasting insulin level (mIU/L)	9.53 ± 1.72	8.39 ± 1.19	5.847	0.000
Blood uric acid (μmol/L)	377.65 ± 65.23	358.07 ± 33.29	4.333	0.000
Urea nitrogen (mmol/L)	11.84 ± 2.03	8.67 ± 1.67	12.999	0.000

BMI: Body mass index; eGFR: Estimated glomerular filtration rate; T2DM: Type 2 diabetes mellitus; DN: Diabetic nephropathy.

Table 2 Comparison of inflammatory indicators and trimethylamine N-oxide between the two groups of patients (mean ± SD)

	DN group (n = 115)	T2DM group (n = 115)	t	P value
CRP (mg/L)	12.16 ± 5.44	6.95 ± 1.77	5.760	0.000
IL-6 (ng/L)	331.14 ± 72.13	245.57 ± 42.04	9.749	0.000
IL-8 (ng/L)	345.04 ± 86.16	314.12 ± 75.13	10.659	0.000
TNF-α (ng/L)	11.28 ± 4.55	7.15 ± 1.80	2.972	0.003
TMAO (ng/mL)	123.47 ± 22.65	108.06 ± 17.62	9.041	0.000

T2DM: Type 2 diabetes mellitus; DN: Diabetic nephropathy; TMAO: Trimethylamine N-oxide; CRP: C-reactive protein; IL-6: Interleukin-6; IL-8: Interleukin-8; TNF-α: Tumor necrosis factor.

Table 3 Comparison of bone metabolism indexes between the two groups (mean ± SD)

	DN group (n = 115)	T2DM group (n = 115)	t	P value
PINP (μg/L)	43.13 ± 6.11	35.51 ± 4.87	10.461	0.000
β-CTX (ng/mL)	0.51 ± 0.11	0.43 ± 0.08	5.996	0.000
ALP (U/L)	69.16 ± 7.12	65.61 ± 7.09	3.788	0.000
Lumbar spine BMD (g/cm2)	0.77 ± 0.14	0.81 ± 0.14	-2.552	0.011
Hip BMD (g/cm2)	0.66 ± 0.11	0.71 ± 0.12	-3.624	0.000

BMD: Bone mineral density; PINP: Procollagen type I N-terminal propeptide; β-CTX: Β-CrossLaps; ALP: Alkaline phosphatase; T2DM: Type 2 diabetes mellitus; DN: Diabetic nephropathy.