Table 2.
Evaluation of non-continuous variables impacting on cognitive impairment among non-dialysis CKD patients by odd ratios.
| Risk factor | No. of studies included | Effect estimate (OR) | 95% CI | p Value | Heterogeneity tau2, I2 |
|---|---|---|---|---|---|
| Female | 7 | 1.33 | 0.92–1.90 | <.01 | 0.1726, 78% |
| Lower education | 5 | 2.59 | 1.32–5.09 | <.01 | 0.5101, 90% |
| Smoking | 5 | 0.78 | 0.61–1.01 | .13 | 0.0906, 44% |
| Hypertension | 6 | 1.26 | 0.78–2.05 | <.01 | 0.2305, 69% |
| Type 2 diabetes mellitus | 6 | 1.55 | 1.33–1.81 | .11 | 0.0359, 44% |
| Cardiovascular disease | 6 | 1.63 | 1.20–2.22 | .05 | 0.0724, 55% |
| Cerebrovascular disease | 5 | 1.95 | 1.55–2.45 | .12 | 0.0657, 45% |
OR: odds ratio.
The data were obtained by statistical analysis using R software (R Foundation for Statistical Computing, Vienna, Austria). I2 was used to assess the degree of consistency among study results. If I2 < 50%, the heterogeneity between the included studies can be ignored, and the fixed-effect model combined with the effect size was selected, or the random effect model was selected.