HHS Public Access Author manuscript Author Manuscript
J Am Geriatr Soc. Author manuscript; available in PMC 2017 April 01. Published in final edited form as: J Am Geriatr Soc. 2016 April ; 64(4): 882–883. doi:10.1111/jgs.14047.
Age Modifies the Association Between Obesity and Mortality Among Hospitalizations for Severe Sepsis Lauren M. Abbate, MD, PhD1,2, Sarah M. Perman, MD, MSCE1,2, Eric T. Clambey, PhD1,3, Rachael E. Van Pelt, PhD1,4, and Adit A. Ginde, MD, MPH1,2 1University
of Colorado School of Medicine, Aurora, CO
Author Manuscript
2Department
of Emergency Medicine
3Department
of Anesthesiology
4Department
of Medicine, Division of Geriatric Medicine
Keywords Sepsis; obesity; mortality; epidemiology
To the Editor
Author Manuscript
While obesity is strongly associated with several chronic conditions(1), the role of obesity during acute illness is less clear, with some studies describing an “obesity paradox,” an apparent protective effect of obesity(2). Preliminary studies suggest that obesity may be associated with lower mortality among those with sepsis(3, 4), though some evidence is conflicting(5, 6). While the incidence and case fatality of sepsis is higher among older adults, it is unknown whether obesity-related immune dysregulation and clinical outcomes differs across the age spectrum. The objective was to determine whether the association between obesity and sepsis mortality is modified by age.
METHODS This was a secondary analysis using data from the 2010 and 2011 California State Inpatient Database (SID), part of the Agency for Healthcare Research and Quality’s Healthcare
Author Manuscript
Corresponding Author: Adit A. Ginde, MD, MPH, Department of Emergency Medicine, University of Colorado School of Medicine, Leprino Building, 7th Floor, Campus Box B-215, 12401 E. 17th Avenue, Aurora, CO 80045, Phone: 720-848-6777, Fax: 720-848-7374, [email protected]. Alternate Corresponding Author: Lauren M. Abbate, MD, PhD, [email protected]. These data were presented as a poster presentation the American College of Emergency Physicians annual Scientific Assembly in October 2014. Author Contributions: Dr. Abbate and Adit A. Ginde were involved in the project conception, statistical analysis, data interpretation, and manuscript preparation. Adit A. Ginde had full access to all of the data. Sarah M. Perman, Eric T. Clambey, and Rachael E. Van Pelt were involved in data interpretation and made significant intellectual contributions to the manuscript draft and revisions. All authors reviewed and approved the submitted version of the manuscript. Sponsor’s Role: The sponsors had no role in the design, analysis, interpretation, or presentation of the study. Conflict of Interest: Dr. Abbate was supported by NIH grant T32AG000279, and Dr. Ginde was supported by NIH grant K23AG040708.
Abbate et al.
Page 2
Author Manuscript
Utilization Project (HCUP) (Rockville, MD, USA). We included hospital visits for adults aged ≥ 20 years who were hospitalized from the emergency department with an explicit ICD-9 discharge diagnosis of severe sepsis (995.92) or septic shock (785.52). Obesity was defined by the validated ICD-9-based chronic disease indicator provided by the HCUP. This is a dichotomous (yes/no) variable based on the ICD-9 code for obesity, as actual body mass index (BMI) or other body composition measurements were not available. The primary outcome was in-hospital mortality. Demographic co-variates included age (analyzed in decades), sex, and race/ethnicity. Other factors, coded as dichotomous (yes/no) variables, included skilled nursing facility residence and co-morbidities defined by the validated ICD-9-based chronic disease indicator provided in HCUP for diabetes, hypertension, congestive heart failure, chronic pulmonary disease, cancer and renal failure.
Author Manuscript
Multivariable logistic regression models were constructed to calculate odds ratios (OR) and 95% confidence intervals (CI) for the adjusted association between obesity and in-hospital mortality. In order to evaluate effect modification by age, we constructed separate adjusted obesity-mortality models stratified by each age category. Analyses were performed using Stata 12.1 (StataCorp LP, College Station, TX).
RESULTS There were 116,566 visits that met our inclusion criteria, of which 13,991 (12.0%) visits were coded as having obesity. Overall, 30,712 (26.3%) visits resulted in death during the hospital admission. Visits with obesity had substantially lower in-hospital mortality (18.4%), compared to the 27.4% for non-obese visits (absolute difference -9.0%; 95% CI, -9.7 to -8.3).
Author Manuscript
After adjusting for co-variates, obesity was inversely associated with in-hospital mortality (OR=0.74 [95%CI, 0.71–0.77]). In the adjusted models stratified by age category, the obesity-mortality association differed by age with younger age groups having minimal association (20–29 years (OR=0.96 [95%CI, 0.61–1.51]), 30–39 years (OR=1.09 [95%CI, 0.85–1.42]) and 40–49 years (OR=0.94 [95%CI, 0.80–1.10]) compared to older age groups (50–59 years (OR=0.76 [95%CI, 0.68–0.84], 60–69 years (OR=0.75 [95%CI, 0.68–0.82]), 70–79 years (OR=0.75 [95%CI, 0.68–0.82]), 80–89 years (OR=0.62 [95% CI, 0.55–0.70]), and ≥ 90 years (OR=0.73 [95%CI, 0.51–1.04]) (Figure 1). Similar results were observed when age categories were dichotomized to age
J Am Geriatr Soc. Author manuscript; available in PMC 2017 April 01. Published in final edited form as: J Am Geriatr Soc. 2016 April ; 64(4): 882–883. doi:10.1111/jgs.14047.
Age Modifies the Association Between Obesity and Mortality Among Hospitalizations for Severe Sepsis Lauren M. Abbate, MD, PhD1,2, Sarah M. Perman, MD, MSCE1,2, Eric T. Clambey, PhD1,3, Rachael E. Van Pelt, PhD1,4, and Adit A. Ginde, MD, MPH1,2 1University
of Colorado School of Medicine, Aurora, CO
Author Manuscript
2Department
of Emergency Medicine
3Department
of Anesthesiology
4Department
of Medicine, Division of Geriatric Medicine
Keywords Sepsis; obesity; mortality; epidemiology
To the Editor
Author Manuscript
While obesity is strongly associated with several chronic conditions(1), the role of obesity during acute illness is less clear, with some studies describing an “obesity paradox,” an apparent protective effect of obesity(2). Preliminary studies suggest that obesity may be associated with lower mortality among those with sepsis(3, 4), though some evidence is conflicting(5, 6). While the incidence and case fatality of sepsis is higher among older adults, it is unknown whether obesity-related immune dysregulation and clinical outcomes differs across the age spectrum. The objective was to determine whether the association between obesity and sepsis mortality is modified by age.
METHODS This was a secondary analysis using data from the 2010 and 2011 California State Inpatient Database (SID), part of the Agency for Healthcare Research and Quality’s Healthcare
Author Manuscript
Corresponding Author: Adit A. Ginde, MD, MPH, Department of Emergency Medicine, University of Colorado School of Medicine, Leprino Building, 7th Floor, Campus Box B-215, 12401 E. 17th Avenue, Aurora, CO 80045, Phone: 720-848-6777, Fax: 720-848-7374, [email protected]. Alternate Corresponding Author: Lauren M. Abbate, MD, PhD, [email protected]. These data were presented as a poster presentation the American College of Emergency Physicians annual Scientific Assembly in October 2014. Author Contributions: Dr. Abbate and Adit A. Ginde were involved in the project conception, statistical analysis, data interpretation, and manuscript preparation. Adit A. Ginde had full access to all of the data. Sarah M. Perman, Eric T. Clambey, and Rachael E. Van Pelt were involved in data interpretation and made significant intellectual contributions to the manuscript draft and revisions. All authors reviewed and approved the submitted version of the manuscript. Sponsor’s Role: The sponsors had no role in the design, analysis, interpretation, or presentation of the study. Conflict of Interest: Dr. Abbate was supported by NIH grant T32AG000279, and Dr. Ginde was supported by NIH grant K23AG040708.
Abbate et al.
Page 2
Author Manuscript
Utilization Project (HCUP) (Rockville, MD, USA). We included hospital visits for adults aged ≥ 20 years who were hospitalized from the emergency department with an explicit ICD-9 discharge diagnosis of severe sepsis (995.92) or septic shock (785.52). Obesity was defined by the validated ICD-9-based chronic disease indicator provided by the HCUP. This is a dichotomous (yes/no) variable based on the ICD-9 code for obesity, as actual body mass index (BMI) or other body composition measurements were not available. The primary outcome was in-hospital mortality. Demographic co-variates included age (analyzed in decades), sex, and race/ethnicity. Other factors, coded as dichotomous (yes/no) variables, included skilled nursing facility residence and co-morbidities defined by the validated ICD-9-based chronic disease indicator provided in HCUP for diabetes, hypertension, congestive heart failure, chronic pulmonary disease, cancer and renal failure.
Author Manuscript
Multivariable logistic regression models were constructed to calculate odds ratios (OR) and 95% confidence intervals (CI) for the adjusted association between obesity and in-hospital mortality. In order to evaluate effect modification by age, we constructed separate adjusted obesity-mortality models stratified by each age category. Analyses were performed using Stata 12.1 (StataCorp LP, College Station, TX).
RESULTS There were 116,566 visits that met our inclusion criteria, of which 13,991 (12.0%) visits were coded as having obesity. Overall, 30,712 (26.3%) visits resulted in death during the hospital admission. Visits with obesity had substantially lower in-hospital mortality (18.4%), compared to the 27.4% for non-obese visits (absolute difference -9.0%; 95% CI, -9.7 to -8.3).
Author Manuscript
After adjusting for co-variates, obesity was inversely associated with in-hospital mortality (OR=0.74 [95%CI, 0.71–0.77]). In the adjusted models stratified by age category, the obesity-mortality association differed by age with younger age groups having minimal association (20–29 years (OR=0.96 [95%CI, 0.61–1.51]), 30–39 years (OR=1.09 [95%CI, 0.85–1.42]) and 40–49 years (OR=0.94 [95%CI, 0.80–1.10]) compared to older age groups (50–59 years (OR=0.76 [95%CI, 0.68–0.84], 60–69 years (OR=0.75 [95%CI, 0.68–0.82]), 70–79 years (OR=0.75 [95%CI, 0.68–0.82]), 80–89 years (OR=0.62 [95% CI, 0.55–0.70]), and ≥ 90 years (OR=0.73 [95%CI, 0.51–1.04]) (Figure 1). Similar results were observed when age categories were dichotomized to age
