Osteoporotic fracture rates in chronic hemodialysis and effect of heparin exposure: a retrospective cohort study.

BACKGROUND: Patients receiving chronic hemodialysis treatments are at a higher risk of fracture compared to the general population. While the use of heparin during dialysis is crucial to avoid thrombosis of the extracorporeal circuit, the association of unfractionated heparin (UFH) and the risk of osteoporotic fracture has been shown for many years. However, this association was not as clear for low-molecular-weight heparin (LMWH) and the few collected data originated from studies among pregnant women. Our aim was to measure osteoporotic fracture rate among hemodialysis patients and to evaluate the association of LMWH compared to UFH in hemodialysis. METHODS: A retrospective cohort study was conducted on data extracted from the RAMQ and Med-Echo databases from January 2007 to March 2013 with patients chronically hemodialyzed in 21 participating centers. Incidence rates for each fracture sites were measured per 1000 patient-year (p-y) and their 95% confidence intervals (CI). Osteoporotic fracture risk for a first event with LMWH compared to UFH was estimated using a cox proportional hazard model using demographics, comorbidities and drug use as covariates. RESULTS: 4796 patients undergoing chronic hemodialysis were identified. The incidence rate for all fracture sites was 22.7 /1000 p-y (95% CI: 19.6-26.1) and 12.8 /1000 p-y (95% CI: 10.5-15.4) for hip and femur fractures. We found a similar risk of osteoporotic fracture for LMWH compared to UFH (adjusted HR = 1.01; 95%CI: 0.72-1.42). Age and malignancy increased the risk of fracture while cerebrovascular disease decreased the risk of fracture. CONCLUSIONS: Compared to UFH, LMWH did not change the risk of osteoporotic fracture when used for the extracorporeal circuit anticoagulation in chronic hemodialysis.

Association between acetylsalicylic acid and the risk of dialysis-related infections or septicemia among incident hemodialysis patients: a nested case-control study.

BACKGROUND: Vascular access-related infections and septicemia are the main causes of infections among hemodialysis patients, the majority of them caused by Staphylococcus species. Acetylsalicylic acid (ASA) has recently been reported with a probable antistaphylococcal activity. This study aimed to evaluate the effect of ASA on the risk of dialysis-related infection and septicemia among incident chronic hemodialysis patients. METHODS: In a nested case-control study, we identified 449 cases of vascular access-related infections and septicemia, and 4156 controls between 2001 and 2007 from our incident chronic hemodialysis patients' cohort. Cases were defined as patients hospitalized with a main diagnosis of vascular access-related infection or septicemia on the discharge sheet (ICD-9 codes). Up to ten controls per case were selected by incidence density sampling and matched to cases on age, sex and follow-up time. ASA exposure was measured at the admission and categorized as: no use, low dose (80-324 mg/d), high dose (≥325 mg/d). Odds ratios (OR) for infections were estimated using multivariable conditional logistic regression analysis, adjusting for potential confounders. RESULTS: Compared to no use, neither dose of ASA was associated with a decreased risk of infection: low dose (OR 1.03, 95 % CI 0.82-1.28) and high dose (OR 1.30, 95 % CI 0.96-1.75). However, diabetes (OR = 1.32, 95 % CI = 1.07-1.62) and anticoagulant use (OR = 1.62, 95 % CI = 1.30-2.02) were associated with a higher risk. CONCLUSION: Among hemodialysis patients, ASA use was not associated with a reduced risk of hospitalizations for dialysis-related infections or septicemia. However, ASA may remain beneficial for its cardiovascular indications.

Outcomes of Infection-Related Hospitalization according to Dialysis Modality.

BACKGROUND AND OBJECTIVES: Peritoneal dialysis (PD) is associated with an increased risk of infection-related hospitalization (IRH) compared with hemodialysis. The objective of this study was to compare mortality and overall readmission after an IRH between PD and hemodialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This propensity score-matched retrospective cohort study assessed patients undergoing long-term dialysis patients, derived from the Canadian Organ Replacement Register and Régie de l'assurance maladie du Québec, who had at least one IRH between January 2001 and December 2007. Patients were followed until death, kidney transplantation, or end of the study period. To estimate the probability of receiving PD versus hemodialysis, propensity scores were obtained using multivariable logistic regression. Mortality and overall readmission risks after the initial IRH were compared using a Cox survival model. RESULTS: A total of 354 pairs of patients who had at least one IRH were matched for propensity score. During follow-up (median, 1.25 years), 138 hemodialysis patients (24.7/100 patient-years; 95% confidence interval [95% CI], 20.7 to 29.1) and 130 PD patients (21.2/100 patient-years; 95% CI, 17.7 to 25.1) died; 265 hemodialysis patients (144.6/100 patient-years; 95% CI, 127.7 to 163.1) and 299 PD patients (173.2/100 patient-years; 95% CI, 154.1 to 194.0) were readmitted for any cause; and 121 hemodialysis patients (29.7/100 patient-years; 95% CI, 24.7 to 35.5) and 168 PD patients (44.7/100 patient-years; 95% CI, 38.2 to 52.0) were readmitted for an infection. Compared with hemodialysis, PD was not associated with a different mortality risk after an IRH (hazard ratio [HR], 0.87; 95% CI, 0.69 to 1.11). PD was associated with a higher risk of infection-related overall readmission compared with hemodialysis (HR, 1.44; 95% CI, 1.14 to 1.81), but not with the risk of all-cause overall readmission (HR, 1.15; 95% CI, 0.98 to 1.36). CONCLUSIONS: PD was not associated with higher mortality or all-cause overall readmission following an IRH compared with hemodialysis, but PD patients were at higher risk of infection-related overall readmission after IRH. IRHs are associated with significant mortality and overall readmissions. Evaluation of strategies to reduce infections in both hemodialysis and PD recipients are needed to improve patient care and outcomes.

Association between vitamin D receptor activator and the risk of infection-related hospitalizations among incident hemodialysis patients: a nested case-control study.

BACKGROUND: Patients suffering from chronic kidney disease are at greater risk of developing infection than the normal population, and infections are the second cause of mortality after cardiovascular complications in this population. Some reports suggest that the intake of active vitamin D might be beneficial to prevent infections. Therefore, we aimed to determine if the oral intake of vitamin D receptor activator (VDRA) is associated with a lower risk of infection-related hospitalization (IRH) among incident chronic hemodialysis patients. METHODS: We conducted a nested case-control study in a cohort of 4933 patients initiating chronic hemodialysis between 1 January 2001 and 31 December 2007 in Quebec, Canada, using administrative databases. We identified cases of hospital admission indicating an infection as main diagnosis on the hospital's discharge sheet. Up to 10 controls were randomly selected for each case. Association between oral VDRA use and risk of IRH was estimated using conditional logistic regression. RESULTS: We identified 1136 cases of IRH and 10396 controls during the study period. The intake of VDRA was not associated with the risk of being hospitalized due to an infection (odds ratio [OR], 1.07; 95% confidence interval [CI], 0.95-1.20). Using the prior 6-month cumulative dose of VDRA, we also found that a cumulative VDRA dose of less than 45 mcg (OR, 1.05; 95%CI, 0.92-1.19) or greater than 45 mcg (OR, 1.15; 95%CI, 0.96-1.36) was not associated with the IRH risk. CONCLUSIONS: The oral intake of VDRA was not associated with the risk of IRH in incident hemodialysis patients.