Categorical parameters including the previous ulceration, callus and amputation history along with the lifestyle factors like smoking and drinking habits for all participants and for each group with and with no future ulceration occurrence.
| Categorical variable | All (1810) | No ulcer occurrence (1687 (93.2%)) | With ulcer occurrence (123 (6.8%)) | Survival analysis Cox univariate regression | Univariate logistic regression | Chi-square test of independence | Kaplan-Meier survival analysis | ||||||
| Count | % | Count | % | Count | % | HR (95% CI)* | P value Cox survival analysis * | OR (95% CI)† | P value univariate logistic regression† | P value for differences‡ | Estimated mean reduction in survival (days)§ | P value for reduction in survival § | |
| Male | 1012 | 55.9 | 944 | 56.0 | 68 | 53.3 | 1.023 (0.717 to 1.460) | 0.898 | 0.973 (0.673 to 1.406) | 0.885 | 0.959 | 2 | 0.899 |
| Previous ulceration | 14 | 0.8 | 10 | 0.6 | 4 | 3.3 | 2.796 (1.029 to 7.598) | 0.035 | 5.624 (1.738 to 18.198) | 0.004 | 0.007 | 869 | 0.035 |
| Amputation | 6 | 0.3 | 5 | 0.3 | 1 | 0.8 | 1.851 (0.258 to 13.263) | 0.534 | 2.757 (0.320 to 23.788) | 0.356 | 0.881 | 875 | 0.534 |
| Presence of callus | 297 | 16.4 | 260 | 15.4 | 37 | 30.1 | 1.474 (0.999 to 2.174) | 0.049 | 2.361 (1.571 to 3.549) | 0.000 | 0.000 | 191 | 0.049 |
| No smoking | 1404 | 77.6 | 1313 | 77.8 | 91 | 74.0 | 0.209 | ||||||
| Past smoker | 300 | 16.6 | 273 | 16.2 | 27 | 22.0 | 1.686 (1.097 to 2.592) | 0.017 | 1.427 (0.911 to 2.235) | 0.121 | 324 | 0.016 | |
| Current smoker | 106 | 5.9 | 101 | 6.0 | 5 | 4.1 | 0.754 (0.306 to 1.856) | 0.539 | 0.714 (0.284 to 1.797) | 0.475 | 57 | 0.546 | |
| Never consumed alcohol | 996 | 55.0 | 928 | 55.0 | 68 | 55.3 | 0.351 | ||||||
| Used to consume alcohol in the past | 568 | 31.4 | 525 | 31.1 | 43 | 35.0 | 1.319 (0.898 to 1.936) | 0.158 | 1.118 (0.752 to 1.662) | 0.582 | 90 | 0.161 | |
| Currently consume alcohol | 246 | 13.6 | 234 | 13.9 | 12 | 9.8 | 0.720 (0.389 to 1.330) | 0.294 | 0.700 (0.373 to 1.314) | 0.267 | 109 | 0.299 | |
| Dry skin | 1623 | 89.7 | 1506 | 89.3 | 117 | 95.1 | 1.926 (1.273 to 2.914) | 0.001 | 2.344 (1.017 to 5.400) | 0.046 | 0.076 | 470 | 0.001 |
P values <0.05 indicate a significant association and are shown in bold in the table.
*Based on univariate Cox survival analysis.
†Based on univariate logistic regression.
‡P values based on χ2 test of independence (with Yates continuity correction).
§Based on Kaplan-Meier survival analysis.