Follow-Up Period for Assessing Mortality Outcomes in Injured Older Adults
Follow-Up Period for Assessing Mortality Outcomes in Injured Older Adults
Objectives: To compare mortality rates of hospitalized injured aged 67 and older across commonly used follow-up periods (e.g., in-hospital, 30-day, 1-year) and to determine the postinjury time after which mortality rates stabilize.
Design: Retrospective analysis of Medicare claims.
Setting: Oregon and Washington Medicare patients.
Participants: Patients admitted to 171 Oregon and Washington facilities during 2001/02 with injuries identified according to International Classification of Diseases, Ninth Revision, code and followed for 1 year.
Measurements: The primary outcome was in-hospital mortality and mortality at 30, 60, 90, 180, and 365 days. Kaplan-Meier survival curves and daily postadmission mortality rates were also evaluated. The rate of change (slope) of the survival curves and daily mortality rates were analyzed to select the point after which mortality rates were no longer decreasing.
Results: There were 32,135 injured older adults hospitalized over the 2-year period, with a median age of 82 (interquartile range 77–88). Cumulative in-hospital mortality and at 30, 60, 90, 180, and 365 days was 4.1%, 9.7%, 13.6%, 16.1%, 21.3%, and 28.4%, respectively. Mortality rates stabilized by 6 months after injury, with 89% of the change occurring within 60 days. Although serious injuries, medical comorbidities, and preinjury nursing facility residence were all associated with higher mortality, they did not affect the pattern of mortality after injury.
Conclusion: In-hospital mortality is much lower than postdischarge mortality in injured older adults, with a substantial portion of persons dying shortly after discharge from the hospital. Mortality appears to stabilize by 6 months after injury, although 60-day postadmission follow-up captures most of the excess daily mortality rate.
Injuries in older adults are a common cause of morbidity and mortality. Although mortality is a crude measure of global function and health, it is easily categorized and represents a commonly assessed outcome in research and clinical care. However, a preferred follow-up period after injury for assessing mortality remains unclear. Follow-up periods used in previous geriatric injury studies are highly variable, ranging from the in-hospital period to up to 6 years after injury. Commonly used follow-up periods include in hospital; 30, 60, and 90 days; 6 months; and 1 year. Selection of the follow-up period is often based on convenience, availability of data, available resources, costs, and other factors. Many existing sources of data (e.g., administrative hospital discharge databases, and most trauma registries) track clinical outcomes only during the acute hospital stay. Mortality estimates based solely on the in-hospital period might underestimate the significance of injuries, because early mortality after discharge is greater than observed hospital mortality. For researchers, factors unrelated to injury severity or quality of care, which may include provider practices, regional standards of care, insurance status, social circumstances (e.g., living alone), hospital availability of a case manager, and access to skilled nursing and rehabilitation facilities, may heavily bias comparisons of in-hospital mortality.
An ideal duration for follow-up will balance the missed injury-associated mortality seen when patients are followed for too short a period with the costs, resources, and proportion of patients lost to follow-up seen with longer surveillance. Assessment of the duration of follow-up after which there is minimal change in the mortality rate would provide a guideline for future geriatric injury research, assist in measuring the effect of interventions, and better define the high-risk period after injury for greater clinical vigilance.
The objective of this study was to compare mortality differences of hospitalized injured older adults across commonly used follow-up periods (e.g., in-hospital, 30-day, 1-year) and to determine the postinjury point after which daily mortality rates have minimal change.
Abstract and Introduction
Abstract
Objectives: To compare mortality rates of hospitalized injured aged 67 and older across commonly used follow-up periods (e.g., in-hospital, 30-day, 1-year) and to determine the postinjury time after which mortality rates stabilize.
Design: Retrospective analysis of Medicare claims.
Setting: Oregon and Washington Medicare patients.
Participants: Patients admitted to 171 Oregon and Washington facilities during 2001/02 with injuries identified according to International Classification of Diseases, Ninth Revision, code and followed for 1 year.
Measurements: The primary outcome was in-hospital mortality and mortality at 30, 60, 90, 180, and 365 days. Kaplan-Meier survival curves and daily postadmission mortality rates were also evaluated. The rate of change (slope) of the survival curves and daily mortality rates were analyzed to select the point after which mortality rates were no longer decreasing.
Results: There were 32,135 injured older adults hospitalized over the 2-year period, with a median age of 82 (interquartile range 77–88). Cumulative in-hospital mortality and at 30, 60, 90, 180, and 365 days was 4.1%, 9.7%, 13.6%, 16.1%, 21.3%, and 28.4%, respectively. Mortality rates stabilized by 6 months after injury, with 89% of the change occurring within 60 days. Although serious injuries, medical comorbidities, and preinjury nursing facility residence were all associated with higher mortality, they did not affect the pattern of mortality after injury.
Conclusion: In-hospital mortality is much lower than postdischarge mortality in injured older adults, with a substantial portion of persons dying shortly after discharge from the hospital. Mortality appears to stabilize by 6 months after injury, although 60-day postadmission follow-up captures most of the excess daily mortality rate.
Introduction
Injuries in older adults are a common cause of morbidity and mortality. Although mortality is a crude measure of global function and health, it is easily categorized and represents a commonly assessed outcome in research and clinical care. However, a preferred follow-up period after injury for assessing mortality remains unclear. Follow-up periods used in previous geriatric injury studies are highly variable, ranging from the in-hospital period to up to 6 years after injury. Commonly used follow-up periods include in hospital; 30, 60, and 90 days; 6 months; and 1 year. Selection of the follow-up period is often based on convenience, availability of data, available resources, costs, and other factors. Many existing sources of data (e.g., administrative hospital discharge databases, and most trauma registries) track clinical outcomes only during the acute hospital stay. Mortality estimates based solely on the in-hospital period might underestimate the significance of injuries, because early mortality after discharge is greater than observed hospital mortality. For researchers, factors unrelated to injury severity or quality of care, which may include provider practices, regional standards of care, insurance status, social circumstances (e.g., living alone), hospital availability of a case manager, and access to skilled nursing and rehabilitation facilities, may heavily bias comparisons of in-hospital mortality.
An ideal duration for follow-up will balance the missed injury-associated mortality seen when patients are followed for too short a period with the costs, resources, and proportion of patients lost to follow-up seen with longer surveillance. Assessment of the duration of follow-up after which there is minimal change in the mortality rate would provide a guideline for future geriatric injury research, assist in measuring the effect of interventions, and better define the high-risk period after injury for greater clinical vigilance.
The objective of this study was to compare mortality differences of hospitalized injured older adults across commonly used follow-up periods (e.g., in-hospital, 30-day, 1-year) and to determine the postinjury point after which daily mortality rates have minimal change.
Source...