Objectives: To determine the mortality rate and risk factors after experiencing symptomatic hyperlactatemia in HIV-infected patients receiving antiretroviral therapy (ART).
Methods: A retrospective cohort study was conducted among patients who were diagnosed with symptomatic hyperlactatemia (lactate >2.5mmol/l) between January 2004 and April 2006. All patients were followed until 3 months after the diagnosis.
Results: One hundred and twenty-five patients were included in the study. The mean+/-standard deviation (SD) age was 39.9+/-10.1 years and body weight was 58.2+/-16.9kg; 60.8% were male. Symptomatic hyperlactatemia in 114 (91.2%) was associated with receiving d4T, in five (4.0%) with d4T+ddI, in four (3.2%) with ZDV+ddI, and in two (1.6%) with ddI (d4T, stavudine; ddI, didanosine; ZDV, zidovudine). The median duration of ART was 13 months. Nine (7.2%) patients died. Patients who died had a higher mean lactate level (8.0 vs. 5.1mmol/l) and mean alanine aminotransferase (ALT; 164 vs. 48U/l) at the time of diagnosis when compared to those who survived (p<0.05). Patients who died had a lower mean weight than those who survived (48 vs. 59kg, p=0.008). By logistic regression, mortality was associated with patients whose body weight was <45kg (p=0.014, odds ratio (OR) 9.090, 95% confidence interval (CI) 1.575-52.632) and whose serum lactate was >10mmol/l (p=0.004, OR 20.372, 95% CI 2.610-159.001).
Conclusions: The mortality rate of symptomatic hyperlactatemia among HIV-infected patients receiving ART is substantial. Almost all patients received d4T. Patients who have a low body weight and high serum lactate level are at a higher risk of mortality.