Five Years of Follow-Up of Patients with Acute Respiratory Distress Syndrome

The acute respiratory distress syndrome (ARDS) is, according to researchers, “an important and costly public health problem.” There have been few studies designed to obtain extensive, longitudinal data from survivors of ARDS in regard to 5-year pulmonary, functional, and health-related quality-of-life outcomes or healthcare utilization and costs. Noting that prospective systematic evaluation of long-term outcomes of survivors of ARDS has been limited to outcomes after 2 years of follow-up, the researchers recently conducted a prospective, longitudinal cohort study of patients (n=109) with ARDS who survived until they were discharged from the intensive care unit (ICU). Results of the study were reported in the New England Journal of Medicine [2011;364(14):1293-1304]. The patients were recruited from 4 academic medical–surgical ICUs in Toronto between May 1998 and May 2001. At the end of year 1, written permission was obtained from patients for another 4 years of follow-up. The median age of the patients at the time of the onset of ARDS was 4 years; 83% had ≤1 preexisting conditions and 83% were working full time. The most common risk factors for ARDS were pneumonia and sepsis. The researchers evaluated the participants at 3, 6, and 12 months and at 2, 3, 4, and 5 years after discharge from the ICU. Patients were examined and interviewed at each visit. In addition, they underwent pulmonary function tests, the 6-minute walk test, resting and exercise oximetry, chest imaging, and a quality-of-life evaluation at each visit. Participants also reported their use of healthcare services. At the 1-year visit, 83 of the 109 patients consented to an additional 4 years of follow-up. By the final year of follow-up, the cohort included 64 of the 109 patients. At the end of the follow-up period, no patient had demonstrable weakness on examination, but all commented on having varying degrees of perceived weakness and said that their ability to do vigorous exercise was reduced compared with their ability prior to their critical illness. At the 5-year follow-up, the median distance walked in 6 minutes was 436 m, which was 76% of the distance walked in an age- and sex-matched control population. The physical component score on the Medical Outcomes Study 36-Item Short-Form (SF-36) health survey was 41; the mean norm score matched for age and sex is 50. Younger patients had a greater rate of recovery than older patients with respect to the SF-36; those in the 2 younger groups (<38 and 38-52 years of age) had a significantly steeper slope in improvement in the physical component score from discharge to 5 years, compared with those >52 years of age (P=.002). However, none of the 3 age groups had a score as high as the predicted score at 5 years. During the first year of follow-up, 12 patients died; 9 others died over the course of the next 4 years. Of the patients followed for 5 years, 83% were working full time prior to their critical illness (n=53). At the 5-year follow-up, 77% had returned to work; of those, 94% returned to their original work. Patients often required a gradual transition to work, a modified work schedule, or job retraining in collaboration with third-party private insurers. The average costs per patient per year from years 3 through 5 ranged from $5000 to $6000. Medication costs increased to year 3 and then leveled off in years 4 and 5. Costs related to rehospitalizations decreased up to 3 years of follow-up and then remained stable in years 4 and 5. The presence of coexisting disease was the only factor significantly associated with costs incurred over the 5-year follow-up period in regression modeling. In conclusion, the researchers summarized their findings: “Exercise limitation, physical and psychological sequelae, decreased physical quality of life, and increased costs and use of healthcare services are important legacies of severe lung injury.”