Impact of body mass index on adverse kidney events in diabetes mellitus patients: A systematic-review and meta-analysis

Table 1 Baseline characteristic of clinical studies included in the analysis

Ref.	Huang etal[18], 2014	Bentata etal[22], 2014	Chen etal[19], 2013	Drion etal[20], 2011	Haupt etal[14], 1999	Mohsen etal[23], 2012	Zhang etal[13],2019	Nakanishi etal[12], 2019	Kanauchi etal[21], 2003	Kim etal[17], 2021	Belhatem etal[16], 2015
Country	Chinese	African	Chinese	Dutchman	Germany	British	Chinese	Japanese	Japanese	Korean	France
Study design	Prospective	Prospective	Retrospective	Retrospective	Prospective	Prospective	Retrospective	Retrospective	Retrospective	Prospective	Retrospective
Institution	Single-center	Single-center	Single-center	Single-center	Single-center	Single-center	Single-center	Single-center	Single-center	Single-center	Single-center
BMI Categories Reported	18.5-22.9: 23-24.9: ≥ 25	18.5–24.9: 25–29.9: ≥ 30	< 25: 25-28: ≥ 28	18-24.9: 25-29.9: ≥ 30	< 25: 25-30: 30–35: > 35	< 30: ≥ 30	< 21.62: 21.62–23.50: 23.51–25.16: 25.17–27.33: > 27.33	Controlled HbA1c non-overweight BMI < 25: controlled HbA1c overweight BMI ≥ 25): UNCONTROLLEd HbA1c non-overweight BMI < 25: uncontrolled HbA1c overweight BMI ≥ 25	≤ 25: > 25	< 23: 23- 25: ≥ 25	< 25: 25-30: 30-40: > 40
BMI Groups	18.5-25: ≥ 25	18.5-25: ≥ 25	< 25: ≥ 25	18-25: ≥ 25	< 25: ≥ 25	< 30: ≥ 30	< 25.17: ≥ 25.17	< 25: ≥ 25	< 25: ≥ 25	< 25: ≥ 25	< 25: ≥ 25
Patient characteristics by BMI groups
Sample size	105	292	264	844	698	229	3224	2306	49	1060	855
Age (yr)	61.98 ± 9.27: 60.60 ± 10.37	61.00 ± 11.00: 59.15 ± 9.28	54.10 ± 9.34: 53.63 ± 8.81	61.84 ± 18.64: 63.18 ± 12.29	46.00 ± 8.40: 45.11 ± 8.93	71.00 ± 9.90: 68.00 ± 9.40	60.72 ± 1.98: 62.18 ± 11.16	64.2 ± 10.4: 57.4 ± 12.9	55.7 ± 9.0: 53.2 ± 9.1	56.48 ± 8.44: 54.10 ± 8.70	60 ± 12: 60.22 ± 10.03
Gender (Male %)	0.6476	0.3801	0.5833	0.5403	0.692	0.655	0.507	0.6015	0.673	0.4557	0.6023
BMI value	22.53 ± 1.36: 22.76 ± 2.09	23.06 ± 1.68: 3.19 ± 3.97	22.60 ± 1.59: 28.44 ± 2.79	23.00 ± 1.49: 30.58.00 ± 54.76		25.90 ± 2.60: 35.00 ± 4.90		21.70 ± 2.30: 28.70 ± 3.40	21.70 ± 2.50: 27.50 ± 2.30	22.65 ± 1.83: 29.4 ± 2.7	22.70 ± 2.00: 32.21 ± 5.88
RAS	51:53:00	64:217	NR	NR	NR	NR	216:243	NR	NR	NR	NR
Hypertension	50:51:00	NR	NR	NR	NR	NR	1130:946	NR	NR	370:344	NR
Follow-up (m)	24	40.51 ± 14.00: 44.85 ± 11.21	The median follow-up time was 39.0 0months (range 0–87.00)	NR	NR	31.00 ± 19.50: 31.00 ± 19.40	NR	NR	NR	NR	NR
Baseline renal characteristics
Serum creatinine (mg/dL)	0.95 ± 0.43: 2.03 ± 0.47	NR	2.39 ± 2.27: 1.72 ± 1.76	0.89 ± 0.23: 0.94 ± 0.27	0.8 ± 0.2: 0.85 ± 0.34	NR	0.69 ± 0.21: 0.73 ± 0.26	0.74 ± 0.28: 0.62 ± 0.15	NR	NR	0.89 ± 0.25: 0.92 ± 0.32
eGFR (ml/min/1.73 m2)	38.83 ± 8.36: 38.33 ± 9.34	85.59 ± 40.93: 80.67 ± 38.19	81.60 ± 51.00: 111.92 ± 60.52	NR	NR	NR	114.01 ± 36.71: 104.35 ± 35.08	NR	108.00 ± 41.00: 134.00 ± 37.00	74.93 ± 12.41: 70.50 ± 13.00	87.00 ± 9: 83.89 ± 30.48
Proteinuria	Daily urinary protein (g/24 h): 3.09 ± 2.62: 2.90 ± 2.35		Urine protein excretion (g/24 h): 3.19 ± 2.19: 3.02 ± 2.55		Albumin (mg in 24-h urine): 64.4 ± 294.9: 170.69 ± 776				Urine protein (g/24 h): 72 (30-266): 67 (30-210)
Follow-up end kidney adverse events	Serum creatinine ≥ 2-fold vs Baseline, Dialysis, or Death	ESRD. ESRD was defined by eGFR < 15 ml/min/1.73 m2 and/or initiation of dialysis.	ESRD. ESRD was defined as the requirement for permanent renal replacement therapy or serum creatinine exceeding 6.0 mg/dL for more than 1 mo without other causes of renal dysfunction	NR	NR	Deceased or commenced on renal replacement therapy	NR	eGFR of < 30 mL/min/1.73 m2 and/or microalbuminuria value of ≥ 30 mg/gCr	NR	eGFR < 60 mL/min/1.73 m2, or albumin/creatinine ratio in spot urine of 30–300 mg/g	NR
The risk of kidney adverse events			RR: 2.88 (95%CI: 1.24-6.66)			RR: 1.26 (95%CI: 0.72-2.22)	OR: 1.32 (95%CI: 1.00-1.71)	HR: 1.03 (95%CI: 1.01-1.07)		OR: 1.40 (95%CI: 1.08-2.04 )	OR: 1.34 (95%CI: 1.03-1.43)

BMI: Body mass index; HbA1c: Glycated hemoglobin; RAS: Renin-angiotensin system blockers; eGFR: Estimated glomerular filtration rate; ESRD: End stage renal disease; RR: Relative risk; HR: Hazard ratio; OR: Odds ratio; CI: Confidence interval.