Table1.

Factors affecting diabetic retinopathy

Factors	Correlation with DR	Modifiable		Comments	Reference
		Yes	No
Age	Positive		No	Patient age (≥50 years) is associated with increased frequency of DR	[38]
Duration of diabetes	Positive		No	Longer duration of diabetes (≥20 years) increases the risk of DR	[39];[40]
Pregnancy	Positive		No	Pregnancy increase the risk of DR	[41];[42]
Hyperglycemia	Positive	Yes		HbA1c > 7% would increase the risk of DR development	[43, 44]
Systolic blood pressure	Positive	Yes		Every increase of 10mmHg in systolic blood pressure leads to 10% risk of early DR and 15% risk of PDR or DME.	[32];[45]
Hyperlipidemia	Indeterminate	Yes		Inconsistent results on the effect of lipid associated with the development and progression of DR and DME	[45];[46]
Obesity	Positive	Yes		Increased waist-hip ratio and waist circumference are positively associated with DR	[47];[40]
Smoking	Positive	Yes		Non-significant positive trend	[48];[49];[50]
Physical activity	Moderate	Yes		Slightly protective effect	[51];[52]
Male Sex	Positive		No	Increased incidence in male	[48];[53]
Myopia	Negative		No	Protective effect towards DR	[54];[55]