Data collection procedure:
To collect the data, we obtained a list of patients who entered the SSCKD during the 2016-2018 period. The SSCKD was created from patients referred from primary care centers attached to the hospital. In the healthcare centers, the physician performed the CKD screening estimating the GFR using the modification dialysis renal disease 4 (MDRD4) formula and the albumin/creatinine ratio in urine at random. Physicians referred patients with an estimated GFR <60 mL/min / 1.73m2 for care with the nephrologist. In the first visit, the nephrologist repeated creatinine and other laboratory data were requested.
Subsequently, we reviewed the laboratory results requested by the nephrologist for the patient’s admission to the database, using the software called ”RESULAB”. We collected serum creatinine (mg/dl), eGFR (ml/min/1,73m2), glucose (mg/dl), total protein (g/dL), albumin (g/dL), glutamic-pyruvic transaminases (U/L), glutamic-oxaloacetic transaminases (U/L), total bilirubin (mg/dL), alkaline phosphatase(U/L), globulin (g/dL), hemoglobin (g/dl), platelets (K/uL), neutrophils (K/uL) and lymphocytes (K/uL). We determined the vital status and date of death through the consultation of the National Registry of Identification and Civil Status (RENIEC, in Spanish) portal. (https://portaladminusuarios.reniec.gob.pe/validacionweb/index.html#no-back-button).
For non-survivors patients, we collected the date of death for any cause to establish the time until the event. For those patients who did not die during the established period, the closure of the follow-up was Oct 31, 2019. We marked the beginning of the follow-up by the patient’s admission to the SSCKD.