Table 4. Ratio of ORs for association between the prevalence of diabetes and each socioeconomic and behavioral factor.

Variables		Overall (2015 to 2021)	Pre-pandemic era (2015 to 2019)	During pandemic era (2020 to 2021)
		Weighted OR (95% CI)	Weighted OR (95% CI)	Weighted OR (95% CI)	Ratio of ORs (95% CI), during pandemic versus pre-pandemic (reference)	P-value
Cataract
Age	40-59 years (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	20-39 years	0.14 (0.09 to 0.24)	0.19 (0.12 to 0.33)	0.01 (0.00 to 0.10)	0.07 (0.01 to 0.56)	0.012
	≥ 60 years	10.47 (8.83 to 12.41)	11.56 (9.45 to 14.15)	8.23 (6.02 to 11.25)	0.71 (0.49 to 1.03)	0.074
Sex	Male (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Female	2.01 (1.81 to 2.22)	2.08 (1.84 to 2.35)	1.82 (1.49 to 2.23)	0.88 (0.69 to 1.11)	0.269
Region of residence	Rural (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Urban	1.08 (0.97 to 1.21)	1.00 (0.88 to 1.14)	1.32 (1.06 to 1.64)	1.31 (1.02 to 1.70)	0.037
Education background	High school or lower (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	College or higher	0.23 (0.20 to 0.26)	0.21 (0.18 to 0.25)	0.26 (0.21 to 0.34)	1.24 (0.92 to 1.67)	0.152
Economic level of family	Low (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	High	0.32 (0.29 to 0.36)	0.29 (0.26 to 0.33)	0.43 (0.35 to 0.53)	1.49 (1.17 to 1.90)	0.001
BMI groupa	Underweight to normal (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Overweight to obese	1.68 (1.52 to 1.86)	1.76 (1.57 to 1.97)	1.49 (1.21 to 1.84)	0.85 (0.67 to 1.08)	0.175
Smoking status	Non-smoker (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Ex-smoker	0.53 (0.44 to 0.64)	0.53 (0.42 to 0.66)	0.54 (0.37 to 0.77)	1.01 (0.66 to 1.55)	0.953
	Smoker	1.14 (1.02 to 1.28)	1.10 (0.97 to 1.26)	1.25 (1.00 to 1.55)	1.13 (0.88 to 1.46)	0.346
Alcohol consumption frequency	Non-drinker (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	1–5 days/month	0.52 (0.46 to 0.59)	0.52 (0.45 to 0.60)	0.53 (0.41 to 0.68)	1.01 (0.76 to 1.35)	0.935
	6–30days/month	0.58 (0.50 to 0.68)	0.57 (0.47 to 0.68)	0.62 (0.46 to 0.82)	1.09 (0.78 to 1.52)	0.623
Glaucoma
Age	40-59 years (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	20-39 years	0.19 (0.11 to 0.33)	0.29 (0.16 to 0.52)	0.02 (0.00 to 0.17)	0.08 (0.01 to 0.63)	0.017
	≥ 60 years	4.01 (3.13 to 5.14)	4.55 (3.40 to 6.08)	3.11 (1.97 to 4.90)	0.68 (0.40 to 1.17)	0.167
Sex	Men (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Women	0.97 (0.79 to 1.18)	0.94 (0.74 to 1.20)	1.03 (0.71 to 1.48)	1.09 (0.70 to 1.69)	0.700
Region of residence	Rural (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Urban	1.03 (0.84 to 1.26)	1.07 (0.84 to 1.36)	0.98 (0.67 to 1.45)	0.92 (0.58 to 1.45)	0.718
Education background	High school or lower (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	College or higher	0.40 (0.32 to 0.50)	0.38 (0.29 to 0.50)	0.42 (0.27 to 0.65)	1.09 (0.65 to 1.83)	0.740
Economic level of family	Low (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	High	0.48 (0.39 to 0.59)	0.45 (0.36 to 0.57)	0.53 (0.35 to 0.81)	1.17 (0.72 to 1.91)	0.528
BMI groupa	Underweight to normal (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Overweight to obese	1.35 (1.11 to 1.66)	1.41 (1.11 to 1.79)	1.22 (0.85 to 1.76)	0.87 (0.56 to 1.34)	0.522
Smoking status	Non-smoker (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Ex-smoker	1.22 (0.91 to 1.63)	1.18 (0.85 to 1.64)	1.33 (0.74 to 2.38)	1.12 (0.58 to 2.20)	0.733
	Smoker	1.86 (1.47 to 2.35)	1.77 (1.35 to 2.32)	2.00 (1.29 to 3.10)	1.13 (0.67 to 1.88)	0.651
Alcohol consumption frequency	Non-drinker (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	1–5 days/month	0.87 (0.68 to 1.11)	0.84 (0.63 to 1.11)	0.95 (0.60 to 1.51)	1.14 (0.67 to 1.95)	0.636
	6–30 days/month	0.92 (0.70 to 1.20)	0.96 (0.70 to 1.32)	0.84 (0.50 to 1.39)	0.87 (0.48 to 1.59)	0.660
Macular degeneration
Age	40-59 years (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	20-39 years	0.19 (0.11 to 0.33)	0.35 (0.15 to 0.80)	0.21 (0.04 to 1.12)	0.61 (0.09 to 3.91)	0.599
	≥ 60 years	4.01 (3.13 to 5.14)	3.67 (2.35 to 5.74)	3.32 (1.80 to 6.14)	0.90 (0.42 to 1.93)	0.794
Sex	Men (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Women	1.06 (0.79 to 1.42)	1.10 (0.77 to 1.57)	1.00 (0.61 to 1.63)	0.91 (0.50 to 1.66)	0.754
Region of residence	Rural (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Urban	1.08 (0.81 to 1.43)	1.11 (0.78 to 1.58)	1.09 (0.67 to 1.77)	0.98 (0.54 to 1.79)	0.950
Education background	High school or lower (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	College or higher	0.41 (0.30 to 0.56)	0.41 (0.28 to 0.60)	0.39 (0.23 to 0.69)	0.97 (0.49 to 1.91)	0.925
Economic level of family	Low (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	High	0.60 (0.45 to 0.79)	0.63 (0.45 to 0.89)	0.53 (0.32 to 0.87)	0.83 (0.46 to 1.53)	0.556
BMI groupa	Underweight to normal (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Overweight to obese	1.45 (1.09 to 1.94)	1.56 (1.10 to 2.21)	1.24 (0.75 to 2.06)	0.80 (0.43 to 1.48)	0.469
Smoking status	Non-smoker (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Ex-smoker	0.83 (0.51 to 1.34)	0.96 (0.54 to 1.71)	0.62 (0.25 to 1.55)	0.64 (0.22 to 1.89)	0.423
	Smoker	2.03 (1.46 to 2.81)	2.12 (1.43 to 3.15)	1.83 (1.05 to 3.19)	0.86 (0.44 to 1.71)	0.673
Alcohol consumption frequency	Non-drinker (ref)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
	1–5 days/month	0.51 (0.35 to 0.74)	0.40 (0.23 to 0.69)	0.70 (0.41 to 1.21)	1.77 (0.82 to 3.82)	0.143
	6–30 days/month	0.67 (0.45 to 1.00)	0.81 (0.51 to 1.27)	0.44 (0.18 to 1.09)	0.54 (0.20 to 1.50)	0.236

BMI, body mass index; CI, confidence interval; KNHANES, Korea National Health and Nutrition Examination Survey; ORs, Odds Ratios.
BMI is divided into two groups: underweight to normal (<23.0 kg/m²), overweight to obese (≥ 23.0 kg/m²)
The numbers in bold indicate a significant difference (p <0.05).