P0600LONG-TERM PROGNOSIS OF PATIENTS WITH METFORMIN -ASSOCIATED LACTIC ACIDOSIS(MALA) AND ACUTE KIDNEY FAILURE

Abstract

Abstract Background and Aims Although metformin-associated lactic acidosis (MALA) is a very rare event, is frequently seen in patients on metformin with risk factors for developing acute kidney injury (AKI). The long-term prognosis in patients with metformin-associated lactic acidosis (MALA) and renal failure remains unknown. To describe the characteristics and prognosis of AKI in patients with MALA and investigate whether prescription of RRT and previous renal function are associated with long-term outcomes. Method A retrospective single-centre case series. One hundred and nine patients affected with MALA and AKI admitted between Marx 2007 and February 2019 were included. We analysed comorbidities, laboratory tests, clinical parameters and prescription pattern of RRT at admission. After discharging, renal outcomes (doubling serum creatinine or starting dialysis) and mortality were assessed in the long-term. Results We included 109 patients (59 males and 50 females), mean age of 74.2±8.6 years and mean Charlson comorbidity index of 8.0±2.4. 54 out of 109 patients had previous chronic kidney disease (eGFR < 60 ml/min/1.72 m2). Precipitating causes of AKI associated MALA included; acute dehydration (84.4%), exposure to iodinated contrast (7.3%) and non-specified causes (8.3%). During the admission, renal replacement therapy (RRT) was performed in 72 patients (continuous renal replacement therapy in 47 and dialysis in 25). RRT requirements was significantly associated with lactate, acidosis and serum creatinine levels, but not was associated with higher mortality rate during admission. The patients were followed a median time of 33 (10-65) months after discharging. 33 patients had a renal event and 55 patients died. The patients with CKD before admission had higher number of renal events (log Rank 6.346, p=0.012) and higher mortality (log Rank 12.943, p<0.001). In a model adjusted by age and RRT at admission, women were less likely to develop (HR 0.315(0.136-0.730, p=0.007) long-term renal events and previous CKD increased this probability (HR 2,532 (1.190-5.385), p=0.016). Previous CKD and RRT during admission increased mortality in a model adjusted by age, gender and comorbidity (HR 2.315(1.177-4.553), p=0.015 and HR 1.895(1.003-3.580), p=0.049, respectively). Conclusion The renal function prior to the episode of AKI associated to MALA and the RRT at admission are the main factors related to renal outcomes and mortality in the long-term.