Table 3. Geometrical measures of retinal venules by ethnic group.
Vessel measure | Europeans (n = 144) | South Asians (n = 143) | P |
Venular vessels, n | 15.1 [14.0, 16.2] | 12.0 [11.2, 12.8] | <0.001 |
Venular vessels (adjusted)§, n | 14.6 [13.6, 15.6] | 12.4 [11.4, 13.4] | 0.006 |
Venular bifurcations, n | 12.8 [11.9, 13.7] | 10.3 [9.6, 11.0] | <0.001 |
Venular bifurcations (adjusted)§, n | 12.9 [12.0, 13.5] | 10.5 [9.7, 11.2] | <0.001 |
Venular diameter, pixels | 25.6 [24.9, 26.2] | 26.3 [25.5, 27.1] | 0.1 |
1st order venular diameter, pixels | 27.0 [26.3, 27.7] | 27.8 [27.0, 28.5] | 0.1 |
Venular length*, pixels | 257 [244, 269] | 282 [267, 299] | 0.01 |
Venular length*(adjusted)§, pixels | 258 [245, 271] | 280 [266, 295] | 0.02 |
Venular LDR | 10.6 [10.0, 11.1] | 11.7 [10.9, 12.5] | 0.02 |
Venular tortuosity (×102) | 0.53 [0.41, 0.67] | 0.83 [0.66, 1.02] | 0.007 |
Venular tortuosity (×102) (adjusted)§ | 0.55 [0.42, 0.70] | 0.78 [0.62, 0.96] | 0.02 |
AVR | 0.87 [0.85, 0.89] | 0.85 [0.83, 0.87] | 0.1 |
Values are mean [95% confidence interval] either unadjusted or § following adjustment for age, sex, body mass index, systolic blood pressure, heart rate, smoking and diabetes. Abbreviations: AVR, arterio-venular ratio; LDR, length diameter ratio.