Potentially preventable hospitalization as a complication of CKD: a cohort study

Background: Ambulatory care-sensitive conditions have been described as those that (if appropriately managed in an outpatient setting) generally do not require subsequent hospitalization. Our goal was to identify clinical populations of people who are at the highest risk of ambulatory care-sensitive conditions related to chronic kidney disease (CKD).

Study design: Retrospective cohort study.

Setting & participants: 2,003,054 adults (including 238,747 adults with CKD) residing in Alberta, Canada, with at least one serum creatinine measurement between 2002 and 2009.

Predictors: Estimated glomerular filtration rate and albuminuria categories, CKD status, demographics, and clinical characteristics.

Outcomes: Hospitalization with heart failure, hyperkalemia, volume overload, or malignant hypertension.

Measurements: We used the Alberta Kidney Disease Network database, which incorporates data from Alberta Health, the Northern and Southern Alberta Renal Programs, and clinical laboratories in Alberta.

Results: During a median follow-up of 4.1 years, 43,863 participants were hospitalized for heart failure; 6,274 participants, for hyperkalemia; 2,035 participants, for volume overload; and 481 participants, for malignant hypertension. All 4 conditions were more common at lower estimated glomerular filtration rates and in the presence of albuminuria. In the subset of participants with CKD, heart failure, hyperkalemia, and volume overload were associated most strongly with older age, diabetes, chronic liver disease, and prior heart failure. Malignant hypertension was associated with prior hypertension, aboriginal status, and peripheral vascular disease. Remote-dwelling participants were more likely to experience heart failure and malignant hypertension than those living closer to providers.

Limitations: No data for medication use or potentially important process-based outcomes for study participants.

Conclusions: Our findings suggest that future studies seeking to determine how to prevent ambulatory care-sensitive conditions in people with CKD should target remote dwellers and those with comorbid conditions such as concomitant heart failure and liver disease.