Infection-related hospitalizations in older patients with ESRD.
BACKGROUND
Infection is an important cause of hospitalization and death in patients receiving dialysis. Few studies have examined the full range of infections experienced by dialysis patients. The purpose of this study is to examine types, rates, and risk factors for infection in older persons starting dialysis therapy.


METHODS
Retrospective observational cohort study.


METHODS
The cohort was assembled from the US Renal Data System and included patients aged 65-100 years who initiated dialysis therapy between January 1, 2000, and December 31, 2002. Exclusions included prior kidney transplant, unknown dialysis modality, or death, loss to follow-up, or transplant during the first 90 days of dialysis therapy. Patients were followed up until death, transplant, or study end on December 31, 2004.


METHODS
Baseline demographics, comorbid conditions, and serum albumin and hemoglobin levels.


METHODS
Infection-related hospitalizations were ascertained using discharge International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Hospitalization rates were calculated for each type of infection. The Wei-Lin-Weissfeld model was used to examine risk factors for up to 4 infection-related events.


RESULTS
119,858 patients were included, 7,401 of whom were on peritoneal dialysis therapy. During a median follow-up of 1.9 years, infection-related diagnoses were observed in approximately 35% of all hospitalizations. Approximately 50% of patients had at least 1 infection-related hospitalization. Rates (per 100 person-years) of pulmonary, soft-tissue, and genitourinary infections ranged from 8.3-10.3 in patients on peritoneal dialysis therapy and 10.2-15.3 in patients on hemodialysis therapy. Risk factors for infection included older age, female sex, diabetes, heart failure, pulmonary disease, and low serum albumin level.


CONCLUSIONS
Use of ICD-9-CM codes, reliance on Medicare claims to capture hospitalizations, use of the Medical Evidence Form to ascertain comorbid conditions, and absence of data for dialysis access.


CONCLUSIONS
Infection-related hospitalization is frequent in older patients on dialysis therapy. A broad range of infections, many unrelated to dialysis access, result in hospitalization in this population.
Dalrymple
Lorien S
LS
Medicine, University of California, Davis, Sacramento, CA 95817, USA. lorien.dalrymple@ucdmc.ucdavis.edu
Johansen
Kirsten L
KL
Chertow
Glenn M
GM
Cheng
Su-Chun
SC
Grimes
Barbara
B
Gold
Ellen B
EB
Kaysen
George A
GA
D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007239:Infections / Q000453:epidemiology* / Q000209:etiology*; D007676:Kidney Failure, Chronic / Q000150:complications*; D008297:Male; D012189:Retrospective Studies