(HealthDay)—Patients in the intensive care unit (ICU) who survive one week or more of mechanical ventilation can be stratified into disability groups based on age and ICU length of stay, according to a study published online March 14 in the American Journal of Respiratory and Critical Care Medicine.

Margaret S. Herridge, M.D., M.P.H., from the University of Toronto, and colleagues evaluated a multicenter cohort of 391 medical/surgical ICU patients who received one or more week of at seven days, and three, six, and 12 months after ICU discharge. Recursive partitioning modeling was used to identify disability risk groups.

The researchers found that the recovery trajectory to one year after ICU discharge was determined by the seven-day post-ICU Functional Independence Measure (FIM), which was also an for one-year mortality. Age and ICU length of stay predicted the seven-day post-ICU FIM. ICU patients could be categorized into four disability groups by two weeks of mechanical ventilation, based on increasing risk for post-ICU disability, ICU and post-ICU health care utilization and disposition.

"ICU survivors of [at least] one week of mechanical ventilation may be stratified into four disability groups based on age and ICU length of stay," the authors write. "These groups determine one-year recovery and health care utilization and are independent of admitting diagnosis and illness severity."