Geographical variation in use of intensive care: a nationwide study

Purpose: To examine whether there is geographical variation in the use of intensive care resources in Denmark concerning both intensive care unit (ICU) admission and use of specific interventions. Substantial variation in use of intensive care has been reported between countries and within the US, however, data on geographical variation in use within more homogenous tax-supported health care systems are sparse. Methods: We conducted a population-based cross-sectional study based on linkage of national medical registries including all Danish residents between 2008 and 2012 using population statistics from Statistics Denmark. Data on ICU admissions and interventions, including mechanical ventilation, noninvasive ventilation, acute renal replacement therapy, and treatment with inotropes/vasopressors, were obtained from the Danish Intensive Care Database. Data on patients' residence at the time of admission were obtained from the Danish National Registry of Patients. Results: The overall age- and gender standardized number of ICU patients per 1000 person-years for the 5-year period was 4.3 patients (95 % CI, 4.2; 4.3) ranging from 3.7 (95 % CI, 3.6; 3.7) to 5.1 patients per 1000 person-years (95 % CI, 5.0; 5.2) in the five regions of Denmark and from 2.8 (95 % CI, 2.8; 3.0) to 23.1 patients per 1000 person-years (95 % CI, 13.0; 33.1) in the 98 municipalities. The age-, gender-, and comorbidity standardized proportion of use of interventions among ICU patients also differed across regions and municipalities. Conclusions: There was only minimal geographical variation in the use of intensive care admissions and interventions at the regional level in Denmark, but more pronounced variation at the municipality level.