ABSTRACT
BACKGROUND: Although hemodialysis (HD) adequacy, single-pool Kt/Vurea (spKt/V), is inversely correlated with body size, each is known to affect patient survival in the same direction. Therefore, we sought to examine the relationship between HD adequacy and mortality according to body mass index (BMI) in HD patients and explore a combination effect of BMI and HD adequacy on mortality risk. METHODS: We retrospectively reviewed patient data from the Korean Society of Nephrology registry, a nationwide database of medical records of HD patients, from January 2001 to June 2017. We included patients ≥18 years old who were receiving maintenance HD. Patients were categorized into three groups according to baseline BMI (< 20 (low), 20 to < 23 (normal), and ≥ 23 (high) kg/m2). Baseline spKt/V was divided into six categories. RESULTS: Among 18,242 patients on HD, the median follow-up duration was 5.2 (IQR, 1.9-8.9) years. Cox regression analysis showed that, compared to the reference (spKt/V 1.2-1.4), lower and higher baseline spKt/V were associated with greater and lower risks for all-cause mortality, respectively. However, among patients with high BMI (n = 5588), the association between higher spKt/V and lower all-cause mortality was attenuated in all adjusted models (Pinteraction < 0.001). Compared to patients with normal BMI and spKt/V within the target range (1.2-1.4), those with low BMI had a higher risk for all-cause mortality at all spKt/V levels. However, the gap in mortality risk became narrower for higher values of spKt/V. Compared to patients with normal BMI and spKt/V in the target range, those with high BMI and spKt/V < 1.2 were not at increased risk for mortality despite low dialysis adequacy. CONCLUSIONS: The association between spKt/V and mortality in HD patients may be modified by BMI.
Subject(s)
Body Mass Index , Kidney Failure, Chronic/mortality , Kidney Failure, Chronic/therapy , Renal Dialysis/standards , Adult , Aged , Female , Humans , Male , Middle Aged , Mortality , Proportional Hazards Models , Retrospective StudiesABSTRACT
The ratio of the area under the free (unbound) concentration-time curve to minimum inhibitory concentration (fAUC/MIC) was proposed to be the pharmacokinetic/pharmacodynamic index most strongly linked to the antibacterial effect of colistin against Acinetobacter baumannii. A retrospective study of patients who received colistin to treat pneumonia caused by extensively drug-resistant (XDR) A. baumannii over a 4-year period was performed to assess the impact of the colistin MIC on mortality. A total of 227 patients were included in the analysis. The 7-day and 14-day mortality rates of patients with XDR A. baumannii pneumonia receiving colistin therapy were 15.0% and 23.8%, respectively. In the multivariate analysis, Acute Physiology and Chronic Health Evaluation (APACHE) II score, days from index culture to first dose of colistin, underlying tumour and septic shock at presentation were independent predictors of mortality in patients with XDR A. baumannii pneumonia receiving colistin therapy. In the univariate analysis, the colistin dose based on ideal body weight (IBW) correlated with patient outcome. Therefore, the use of IBW appeared to be more appropriate to calculate the colistin dosage. In addition, these results highlight the clinical significance of colistin MIC in patients with XDR A. baumannii pneumonia receiving colistin therapy. Although MICs were in the 'susceptible' range, patients infected with isolates with high colistin MICs showed a poorer clinical response rate than patients infected with isolates with low colistin MICs. Further clinical studies are needed to evaluate the roles of colistin MIC for predicting mortality in XDR A. baumannii pneumonia with a high colistin MIC.
