Keeping an eye on the diabetic foot: The connection between diabetic eye disease and wound healing in the lower extremity

Table 1 Studies examining association of diabetic foot disease and diabetic retinopathy

Ref.	Year	Type of study	Sample size (DFU; no DFU)	Source of population	Main findings
Jayaprakash et al[17]	2009	Prospective Case Study	94	India	73.4% prevalence of DR in patients with DFUs
Hwang et al[22]	2017	Retrospective Cohort	100	South Korea	90% prevalence of DR in patients with type 2 DM and DFUs; 55% had PDR
Karam et al[18]	2018	Cross-sectional	182	India	67.6% prevalence of DR in patients diabetic foot disease (including neuropathy, deformation, DFUs, or amputation)
Zafar et al[19]	2019	Cross-sectional	530 (225; 305)	Pakistan	96% of patients with DFUs had DR
Sellman et al[23]	2020	Case Control	270 (90; 180)	Sweden	31% prevalence of PDR in patients with DFUs
Banik et al[21]	2020	Cross-sectional	680 (8; 672)	Bangladesh	65.9% prevalence of DR in patients with DFUs
Ye et al[20]	2014	Retrospective Cohort	829 (61; 768)	China	OR 2.026 for DFUs in patients with DR
Al-Rubeaan et al[6]	2015	Retrospective Cohort	62681 (2071; 60610)	Saudi Arabia	OR 4.45 for diabetic foot disease (including DFUs, gangrene, and amputation) in patients with DR
Harris Nwanyanwu et al[24]	2013	Retrospective Cohort	4617	United States	1.54 HR for those with comorbid non-healing DFUs to progress from NPDR to PDR in three to five years

DR: Diabetic retinopathy; NPDR: Nonproliferative diabetic retinopathy; PDR: Proliferative diabetic retinopathy; DFU: Diabetic foot ulcer; OR: Odds ratio; HR: Hazard ratios.