Dr. Christopher Cox's long-term objectives for this proposed K23 Career Development Award are to: (1) advance the measurement and understanding of health-related quality of life (HRQL) among survivors of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) and (2) obtain advanced training in epidemiology, biostatistics, and survey methods essential to establishing his career in critical care outcomes research. Dr. Cox, an Assistant Professor at Duke, proposes a combined didactic and clinical research experience to achieve these goals. This training program will include formal coursework at the UNC School of Public Health, attendance at clinical research seminars, and conducting a 5-year clinical research project performed under the mentorship of Dr. James Tulsky, an established investigator. Most ALI/ARDS survivors leave the hospital with multisystemic critical illness-associated problems that may impact their HRQL. To improve their HRQL one must be able to measure it. However, there is no gold standard HRQL measure for ALI/ARDS survivors. Generic questionnaires such as the Short Form 36 (SF36) and the EuroQol (EQ5D) have been used most commonly for this purpose, though they do not assess many concerns unique to ALI/ARDS survivors and their responsiveness and interpretability are not well defined for these patients. To move the field forward, HRQL instruments must be developed that are unique to this population.
My specific aims are to: (1) Identify the important attributes of ALI/ARDS survivors' HRQL, (2) Develop and perform the initial validation of an ALI/ARDS survivor-specific HRQL questionnaire based on these attributes, (3) Perform final validation of the ALI/ARDS questionnaire in a prospective cohort of ALI/ARDS survivors, and (4) Identify clinical factors that predict the rate and magnitude of ALI/ARDS survivors' HRQL recovery using state-of-the-art statistical techniques. I will enroll a total of 380 ALI/ARDS survivors from Duke, the Durham VA Medical Center, and UNC in a single project composed of three related studies. First, qualitative analysis of focus groups of 50 patients and caregivers will identify important ways that ALI/ARDS impacts their lives. Next, these unique attributes will be incorporated into an ALI/ARDS-specific HRQL questionnaire that will be validated and refined in a cross-sectional study of 200 ALI/ARDS survivors using factor analysis and comparison of questionnaire scores with other scales and clinical variables. Lastly, we will collect data prospectively at baseline, 2, 4, and 6 months on 130 ALI/ARDS survivors to evaluate the psychometric measurement performance (e.g., construct validity, sensitivity to change, reliability, interpretability) of the ALI/ARDS questionnaire as well as the SF36 and the EQ5D. Linear mixed effects and general growth mixture modeling will identify specific ICU- and post-discharge factors that are associated with HRQL improvement among ALI/ARDS survivors, as well as define specific subgroups of patients with the greatest need. These results will inform clinical trial outcomes measures as well as highlight targets for interventions designed to improve survivors' HRQL.
