TABLE 2.
Characteristics of the negative studies regarding the relationship of Klotho with adverse clinical outcomes (low versus high sKlotho level).
| Author | Year | Country | Study design | N | Sample | Age | eGFR (ml/min) | Follow-up | Outcomes | Conclusion | NOS |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Ciardullo | 2022 | Italy | Observational | 2509 DM | Serum | 60.0 ± 0.2 | CKD1-5 | — | CV events | sKlotho levels were not linked | 8 stars |
| 480 CKD | with CV events | ||||||||||
| Adamska | 2020 | Poland | Prospective | 217 | Serum | 72 ± 11, 72 | No data eGFR<60 | 3 years | Death | sKlotho levels were not related | stars |
| 80 CKD | 50.1 ± 14.0 | to long-term outcomes. | |||||||||
| Bob | 2019 | Romania | Retrospective | 63 CKD | Serum | 58.13 ± 12 | 65.2 ± 32.5 | 12 months | △decline of eGFR | Increased sKlotho was linked with rapid annual decline of eGFR | stars |
| Qian | 2018 | China | Prospective | 112 CKD | Serum | 64.5 ± 12.7 | 37.5 ± 1.9 | 1.5 years | RRT | Changes in sKlotho level, not baseline sKlotho, correlated with RRT or CV | 7 stars |
| CV events | |||||||||||
| events | |||||||||||
| Brandenburg | 2015 | Germany | Prospective | 2,948 | Unknown | 63 ± 10 | eGFR>90 | 9.9 years | CV events | Klotho did not predict | 7 stars |
| eGFR<90 | Death | CV events or death | |||||||||
| Seiler | 2013 | Germany | Prospective | 312 CKD | Plasma | 65.5 ± 12.1 | 43.8 ± 15.6 | 2.2 ± 0.8 years | RRT | Lower sKlotho failed to predict | 8 stars |
| Death | combined adverse outcomes |
N, number; RRT, renal replacement therapy; Scr, serum creatinine; CV, cardiovascular