Machine learning and deep learning in predicting the risk of diabetic kidney disease: A systematic review and meta-analysis

Table 1 Characteristics of included studies

Ref.	Country	Data source	Recruitment period	Single-center/multi-center	Sample size	Inclusion criteria	Definition of positive outcome
Cho et al[22], 2008	South Korea	EHRs	1996-2005	Single-center	292	Confirmed T2DM; age ≥ 18 years; patients underwent up to 20 clinical tests	20 μg/minute to 200 μg/minute in urinary albumin; no microalbumin or renal failure at diabetes diagnosis; prior evidence of diabetic retinopathy
Dagliati et al[23], 2018	Italy	EHRs	2012-2016	Multi-center	943	Confirmed T2DM; no pre-existing complications; sufficient follow-up records	eGFR < 60 mL/minute/1.73 m2; UACR=30 mg/gram to 299 mg/gram (≥ 2 morning samples)
Rodriguez-Romero et al[24], 2019	United States	ACCORD dataset	2001.01-2001.06; 2003.02-2005.10	Multi-center	10251	Confirmed T2DM by ADA criteria; age ≥ 40 with CVD history; age ≥ 55 with high CVD risk; HbA1c 7.5%-9% (multiple drugs); 7.5%-11% (fewer drugs)	Baseline SCr doubling; eGFR < 60 mL/minute/1.73 m2; UACR ≥ 30 mg/gram or 3.4 mg/mmol; UACR ≥ 300 mg/gram or 33.9 mg/mmol; renal failure
Allen et al[25], 2022	United States	EHRs	2007-2020	Multi-center	111046	Confirmed T2DM by ICD-9/10 codes; age ≥ 18 years; ≥5 years follow-up records; required baseline tests (1-year pre-T2DM); albuminuria/reduced eGFR allowed at baseline; no pre-existing CKD or renal transplant	DKD confirmed by ICD-9/10 codes
Dong et al[26], 2022	China	EMRs	2008.10-2019.12	Single-center	2809	Confirmed T2DM by ADA criteria; age ≥ 18 years; 3 years follow-up records	UACR > 30 mg/gram; protein excretion rate > 150 mg/24 hours; urine dipstick test ≥ 1+; eGFR < 60 mL/minute/1.73 m2
Nicolucci et al[27], 2022	Italy	EMRs	NA	Multi-center	147664	Confirmed T2DM by ICD-9 CM codes	Confirmed DKD by ICD-9 CM codes; no pre-existing complication at baseline
Sabanayagam et al[28], 2023	Singapore	SEED study	2004-2011	Multi-center	1365	Random glucose ≥ 11.1 mmol/L; HbA1c ≥ 6.5% (48 mmol/mol); self-reported antidiabetic medication use; diagnosed with diabetes by a physician	eGFR < 60 mL/minute/1.73 m2; ≥ 25% eGFR decline during follow-up
Hosseini Sarkhosh et al[29], 2023	Iran	EHRs	2012-2021	Single-center	1907	Confirmed T2DM by ADA criteria; 5 years follow-up records; no pre-existing DKD at baseline	UACR ≥ 30 mg/gram; eGFR ≤ 60 mL/minute/1.73 m2
Yun et al[30], 2024	China	EHRs	NA	Multi-center	6040	Confirmed T2DM; age ≥ 18 years; ≥ 7 years follow-up records; ≥ 2 hospital visits per year; no pre-existing DKD at baseline or within 2 years	UACR ≥ 30 mg/gram (≥ 3 months); eGFR < 60 mL/minute/1.73 m2; exclude other kidney diseases
Lin et al[31], 2025	China	EHRs	2011-2023	Single-center	3291	Confirmed T2DM by ICD-9/10 codes; age ≥ 18 years; at least one hospital visit following the end of the baseline time window	eGFR < 60 mL/minute/1.73 m2; UACR ≥ 30 mg/gram over 3 months; DKD confirmed by ICD-9/10 codes; protein in urine dipstick test ≥ 1+
Zou et al[32], 2025	China	EHRs	2014.01-2022.12	Single-center	9572	Confirmed T2DM; no pre-existing DKD; ≥ 3 years follow-up records; exclude glomerular/systemic diseases	UACR ≥ 30 mg/gram in 2/3 tests within 3 months to 6 months; eGFR < 60 mL/minute/1.73 m2 for more than 3 months; renal biopsy was consistent with DKD pathological changes
Dei Cas et al[33], 2025	Italy	DARWIN-Renal	2015.01-2021.09	Multi-center	22379	Confirmed T2DM; age ≥ 18 years; ≥ 1 year follow-up records	5 renal disease severity thresholds established by the KDOQI scale based on the eGFR

EHRs: Electronic health records; T2DM: Type 2 diabetes mellitus; eGFR: Estimated glomerular filtration rate; UACR: Urine albumin-creatinine ratio; ACCORD: Action to Control Cardiovascular Risk in Diabetes; ADA: American Diabetes Association; CVD: Cardiovascular disease; SCr: Serum creatinine; ICD-9/10 codes: International Classification of Diseases, 9th/10th Revision; CKD: Chronic kidney disease; DKD: Diabetic kidney disease; EMRs: Electronic medical records; NA: Not available; SEED: Singapore Epidemiology of Eye Diseases; HbA1c: Glycated hemoglobin; DARWIN-Renal: DApagliflozin Real-World evIdeNce-Renal; KDOQI: Kidney Disease Outcomes Quality Initiative.