Table 1.
Baseline characteristics of participants
| Characteristics | Total | NPDR | PDR | |
|---|---|---|---|---|
| n | 367 | 340 | 27 | p |
| Age (years) | 63.8 ± 10.8 | 63.9 ± 11.0 | 63.0 ± 7.8 | 0.691 |
| Sex, n (%) | 0.242 | |||
| Male | 196 (53.4) | 185 (54.4) | 11 (40.7) | |
| Female | 171 (46.6) | 155 (45.6) | 16 (59.3) | |
| Race/ethnicity, n (%) | 0.104 | |||
| Non-Hispanic white | 133 (36.2) | 128 (37.6) | 5 (18.5) | |
| Non-Hispanic black | 121 (33.0) | 109 (32.1) | 12 (44.4) | |
| Mexican American | 76 (20.7) | 71 (20.9) | 5 (18.5) | |
| Other | 37 (10.1) | 32 (9.4) | 5 (18.5) | |
| Marriage, n (%) | 0.245 | |||
| Married | 225 (61.3) | 212 (62.4) | 13 (48.1) | |
| Unmarried | 21 ( 5.7) | 19 (5.6) | 2 (7.4) | |
| Other | 121 (33.0) | 109 (32.1) | 12 (44.4) | |
| BMI, n (%) | 0.161 | |||
| Underweight/normal | 46 (12.6) | 41 (12.1) | 5 (19.2) | |
| Overweight | 129 (35.2) | 124 (36.5) | 5 (19.2) | |
| Obese | 191 (52.2) | 175 (51.5) | 16 (61.5) | |
| Smoking status, n (%) | 0.171 | |||
| Current smokers | 58 (15.8) | 57 (16.8) | 1 (3.7) | |
| Former smokers | 122 (33.2) | 112 (32.9) | 10 (37.0) | |
| Never smokers | 187 (51.0) | 171 (50.3) | 16 (59.3) | |
| HbA1C, n (%) | 0.351 | |||
| < 6.5 | 91 (24.9) | 87 (25.7) | 4 (15.4) | |
| > = 6.5 | 274 (75.1) | 252 (74.3) | 22 (84.6) | |
| HGB(g/dL) | 13.7 ± 1.7 | 13.8 ± 1.7 | 12.7 ± 1.4 | < 0.001 |
| CRP | 0.6 ± 1.1 | 0.6 ± 1.1 | 0.8 ± 0.9 | 0.388 |
| VitD (nmol/L) | 53.0 ± 22.1 | 52.9 ± 21.7 | 54.0 ± 27.4 | 0.803 |
| HDL (mmol/L) | 1.3 ± 0.4 | 1.3 ± 0.4 | 1.3 ± 0.4 | 0.617 |
| Total cholesterol(mmol/L) | 4.9 ± 1.3 | 4.9 ± 1.3 | 5.2 ± 1.2 | 0.175 |
| Family history of diabetes, n (%) | 237 (64.6) | 216 (63.5) | 21 (77.8) | 0.354 |
| Duration of diabetes (years) | 15.4 ± 11.0 | 14.8 ± 11.1 | 21.6 ± 8.8 | 0.002 |
NPDR, non-proliferative diabetic retinopathy; PDR, proliferative diabetic retinopathy; BMI, body mass index; HGB, hemoglobin; CRP, C-reactive protein; Vitamin D, Vit D; HDL, high-density lipoprotein cholesterol