Greg Martin | Emory University (original) (raw)

Papers by Greg Martin

MedGenMed : Medscape general medicine, 2004

Pulmonary artery catheterization is a frequent procedure for hemodynamic monitoring in critically... more Pulmonary artery catheterization is a frequent procedure for hemodynamic monitoring in critically ill patients or high-risk surgical patients. Mechanical and infectious complications are recognized, though catheter dysfunction and malposition are more frequent and often require clinical intervention. We present the case of a Swan-Ganz catheter with the appearance of a mechanical fracture at the distal end, which required clinical and radiographic investigation to determine the nature of the aberrancy. The evaluation of a malfunctioning pulmonary artery catheter (PAC) is a frequent occurrence in the intensive care unit and requires careful clinical consideration and radiographic examination.

Current Opinion in Critical Care, 2014

Comprehensive Physiology, 2012

Acute lung injury (ALI) and its most severe form, acute respiratory distress syndrome (ARDS), wer... more Acute lung injury (ALI) and its most severe form, acute respiratory distress syndrome (ARDS), were presciently described nearly two centuries ago by René Laennec, later to be described clinically in the 1950s and 1960s. Substantial advances have been made in understanding the pathogenesis of these forms of permeability pulmonary edema, including Starling forces and cellular transport mechanisms involved in the generation and resolution of this form of lung injury. Functional animal models and clinically applicable case definitions for ALI and ARDS were instrumental in gaining these new insights. Although no specific pharmacological therapies for ALI and ARDS yet exist, outcomes have improved with advancements in respiratory and fluid-based supportive therapies, and methods to prevent the development or exacerbation of lung injury. Newer targeted therapies continue to be tested for efficacy in this condition where mortality rates frequently exceed 30%. In this article, we review the history of the pathophysiology of lung fluid and solute movement and the seminal clinical observations that brought that history to clinical relevance. We review the relevant lung structure and function and the dynamics of edema formation and resolution, and we describe the related clinical syndromes and the current treatment modalities.

Open Access Journal of Clinical Trials, 2011

Individual intensive care unit (ICU) characteristics including staffing, expertise, continuity, a... more Individual intensive care unit (ICU) characteristics including staffing, expertise, continuity, and team structure, have been associated with patient outcomes. Separately, some aspects of care in ICUs have been implemented through treatment protocols. The United States Critical Illness and Injury Trials Group-Critical Illness Outcomes Study (USCIITG-CIOS) was designed to determine whether the extent of protocol use in ICUs is associated with hospital survival in a large number of US ICUs. Here, we describe the study protocol and analysis plan approved by the USCIITG-CIOS steering committee. USCIITG-CIOS is a prospective, observational, ecological, multicentered study of mixed ICUs in the US. The data to be collected include organizational information for the ICU (eg, protocol availability and utilization, multidisciplinary staffing assessment), and patient level information (eg, demographics, acute and chronic medical conditions). The primary outcome is all-cause hospital mortality, with the objective being to determine whether there is an association between protocol number and hospital mortality for ICU patients. USCIITG-CIOS is powered to detect a 3% difference in crude hospital mortality between high-protocol and low-protocol use ICUs, dichotomized according to protocol number at the median. The analysis will utilize multivariable regression approaches to adjust for outcome clustering by ICU, with secondary linear analysis of protocol number and mortality and a variety of a priori planned ancillary studies. We anticipate at least 60 ICUs participating in USCIITG-CIOS to enroll approximately 6000 study subjects. USCIITG-CIOS is a multicenter study examining the effect of ICU protocols on patient outcomes. These results will inform our understanding of the relationship between protocol availability, use, and patient outcomes in the ICU. Given the shortage of intensivists worldwide, the results of USCIITG-CIOS can be used to promote more effective and reproducible ICU care and outcomes.

Open Access Journal of Clinical Trials, 2011

Hepatology, 2005

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Critical Care Medicine, 2006

Sepsis is an increasingly common and lethal medical condition that occurs in people of all ages. ... more Sepsis is an increasingly common and lethal medical condition that occurs in people of all ages. The influence of age on sepsis risk and outcome is incompletely understood. We sought to determine the independent effect of age on the incidence, severity, and outcome of adult sepsis. Longitudinal observational study using national hospital discharge data. Approximately 500 geographically separated nonfederal acute care hospitals in the United States. Patients were 10,422,301 adult sepsis patients hospitalized over 24 yrs, from 1979 to 2002. None. Incident sepsis cases were age adjusted and characterized by demographics, sources and types of infection, comorbid medical conditions, and hospital discharge status. Elderly patients (> or = 65 yrs of age) accounted for 12% of the U.S. population and 64.9% of sepsis cases, yielding a relative risk of 13.1 compared with younger patients (95% confidence interval, 12.6-13.6). Elderly patients were more likely to have Gram-negative infections, particularly in association with pneumonia (relative risk, 1.66; 95% confidence interval, 1.63-1.69) and to have comorbid medical conditions (relative risk, 1.99; 95% confidence interval, 1.92-2.06). Case-fatality rates increased linearly by age; age was an independent predictor of mortality in an adjusted multivariable regression (odds ratio, 2.26; 95% confidence interval, 2.17-2.36). Elderly sepsis patients died earlier during hospitalization, and elderly survivors were more likely to be discharged to a nonacute health care facility. The incidence of sepsis is disproportionately increased in elderly adults, and age is an independent predictor of mortality. Compared with younger sepsis patients, elderly nonsurvivors of sepsis die earlier during hospitalization and elderly survivors more frequently require skilled nursing or rehabilitative care after hospitalization. These findings have implications for patient care and health care resource prioritization and provide insights for expanded scientific investigations and potential patient interventions.

Critical Care, 2008

Sepsis is one of the most common conditions encountered in the intensive care unit and is the 10t... more Sepsis is one of the most common conditions encountered in the intensive care unit and is the 10th leading cause of death overall in the United States. Both long-term survival and health-related quality of life are reduced in survivors of sepsis, yet there is little knowledge of the effect of sepsis-specific interventions on either long-term survival or health-related quality of life. The present article discusses the importance of studying health-related quality of life as it relates to sepsis management strategies, particularly in the context of pharmacologic therapy with recombinant human activated protein C.

Chest, 2008

Methods-Two hundred eighty-eight consecutive patients with sepsis-induced ALI from 14 ICUs at fou... more Methods-Two hundred eighty-eight consecutive patients with sepsis-induced ALI from 14 ICUs at four hospitals in Baltimore,MDwere prospectively classified as having a pulmonary vs nonpulmonary source of sepsis. Multiple logistic regression was conducted to evaluate the independent association of a pulmonary vs nonpulmonary source of sepsis with inpatient mortality.

Critical Care, 2009

Introduction Sepsis-induced acute lung injury (ALI) has been reported to have a higher case fatal... more Introduction Sepsis-induced acute lung injury (ALI) has been reported to have a higher case fatality rate than other causes of ALI. However, differences in the severity of illness in septic vs. non-septic ALI patients might explain this finding.

Journal of graduate medical education, 2014

Simulation training is widely accepted as an effective teaching tool, especially for dealing with... more Simulation training is widely accepted as an effective teaching tool, especially for dealing with high-risk situations. We assessed whether standardized, simulation-based advanced cardiac life support (ACLS) training improved performance in managing simulated and actual cardiac arrests. A total of 103 second- and third-year internal medicine residents were randomized to 2 groups. The first group underwent conventional ACLS training. The second group underwent two 2 1/2-hour sessions of standardized simulation ACLS teaching. The groups were assessed by evaluators blinded to their assignment during in-hospital monthly mock codes and actual inpatient code sheets at 3 large academic hospitals. Primary outcomes were time to initiation of cardiopulmonary resuscitation, time to administration of first epinephrine/vasopressin, time to delivery of first defibrillation, and adherence to American Heart Association guidelines. There were no differences in primary outcomes among the study arms a...

Background: Sepsis represents a substantial health care burden, and there is limited epidemiologi... more Background: Sepsis represents a substantial health care burden, and there is limited epidemiologic information about the demography of sepsis or about the temporal changes in its incidence and outcome. We investigated the epidemiology of sepsis in the United States, with specific examination of race and sex, causative organisms, the disposition of patients,
and the incidence and outcome.

Methods: We analyzed the occurrence of sepsis from 1979 through 2000 using a nationally representative sample of all nonfederal acute care hospitals in the United States. Data on
new cases were obtained from hospital discharge records coded according to the International Classification of Diseases, Ninth Revision, Clinical Modification.

Results: Review of discharge data on approximately 750 million hospitalizations in the United States over the 22-year period identified 10,319,418 cases of sepsis. Sepsis was more
common among men than among women (mean annual relative risk, 1.28 [95 percent confidence interval, 1.24 to 1.32]) and among nonwhite persons than among white persons
(mean annual relative risk, 1.90 [95 percent confidence interval, 1.81 to 2.00]). Between 1979 and 2000, there was an annualized increase in the incidence of sepsis of 8.7 percent, from about 164,000 cases (82.7 per 100,000 population) to nearly 660,000
cases (240.4 per 100,000 population). The rate of sepsis due to fungal organisms increased by 207 percent, with gram-positive bacteria becoming the predominant pathogens after 1987. The total in-hospital mortality rate fell from 27.8 percent during the
period from 1979 through 1984 to 17.9 percent during the period from 1995 through 2000, yet the total number of deaths continued to increase. Mortality was highest among
black men. Organ failure contributed cumulatively to mortality, with temporal improvements in survival among patients with fewer than three failing organs. The average length of the hospital stay decreased, and the rate of discharge to nonacute care medical facilities increased.

Conclusions: The incidence of sepsis and the number of sepsis-related deaths are increasing, although the overall mortality rate among patients with sepsis is declining. There are also disparities among races and between men and women in the incidence of sepsis. Gram-positive bacteria and fungal organisms are increasingly common causes of sepsis.

International journal of cardiology, 2015

A low testosterone level in men is associated with increased adiposity, insulin resistance, and d... more A low testosterone level in men is associated with increased adiposity, insulin resistance, and dyslipidemia. Whether low testosterone level is associated with arterial stiffness and endothelial and microvascular dysfunction remains unknown and was investigated in this study. Serum testosterone was measured in 237 healthy men aged 50years (SD 12). Endothelial and microvascular function were assessed as brachial artery flow-mediated dilation (FMD) and digital reactive hyperemia index (RHI), respectively. Arterial stiffness was evaluated by tonometry-derived pulse wave velocity (PWV) and central augmentation index (AIX). Mean total testosterone level was 16.3nmol/L (SD 6.11) and 25% of subjects had low levels (<12.0nmol/L). Testosterone level correlated positively with RHI (r=0.24, p<0.001) and inversely with AIX (r=-0.14, p=0.033) but not with FMD or PWV, indicating impaired microvascular hyperemia and arterial elasticity with lower testosterone levels. After multivariate adjus...

The American Journal of Emergency Medicine, 2015

The British journal of nutrition, Jan 16, 2015

Vitamin D deficiency is highly prevalent in the US population and is associated with numerous dis... more Vitamin D deficiency is highly prevalent in the US population and is associated with numerous diseases, including those characterised by inflammatory processes. We aimed to investigate the link between vitamin D status and anaemia, hypothesising that lower vitamin D status would be associated with increased odds of anaemia, particularly anaemia with inflammation. A secondary aim was to examine the effects of race in the association between vitamin D status and anaemia. We conducted a cross-sectional analysis in a cohort of generally healthy adults in Atlanta, GA (n 638). Logistic regression was used to evaluate the association between vitamin D status and anaemia. Serum 25-hydroxyvitamin D (25(OH)D) < 50 nmol/l (compared to 25(OH)D ≥ 50 nmol/l) was associated with anaemia in bivariate analysis (OR 2·64, 95 % CI 1·43, 4·86). There was significant effect modification by race (P= 0·003), such that blacks with 25(OH)D < 50 nmol/l had increased odds of anaemia (OR 6·42, 95 % CI 1·8...

PloS one, 2015

To identify patient characteristics associated with low serum 25-hydroxyvitamin D (25(OH)D) conce... more To identify patient characteristics associated with low serum 25-hydroxyvitamin D (25(OH)D) concentrations in the medical intensive care unit (ICU) and examine the relationship between serum 25(OH)D and the risk for hospital-acquired infections. This is a prospective observational cohort of adult patients admitted to the medical ICU at an urban safety net teaching hospital in Atlanta, Georgia from November 1, 2011 through October 31, 2012 with an anticipated ICU stay ≥ 1 day. Phlebotomy for serum 25(OH)D measurement was performed on all patients within 5 days of ICU admission. Patients were followed for 30 days or until death or hospital discharge, whichever came first. Hospital-acquired infections were determined using standardized criteria from review of electronic medical record. Among the 314 patients analyzed, 178 (57%) had a low vitamin D at a serum 25(OH)D concentration < 15 ng/mL. The patient characteristics associated with low vitamin D included admission during winter m...

MedGenMed : Medscape general medicine, 2004

Pulmonary artery catheterization is a frequent procedure for hemodynamic monitoring in critically... more Pulmonary artery catheterization is a frequent procedure for hemodynamic monitoring in critically ill patients or high-risk surgical patients. Mechanical and infectious complications are recognized, though catheter dysfunction and malposition are more frequent and often require clinical intervention. We present the case of a Swan-Ganz catheter with the appearance of a mechanical fracture at the distal end, which required clinical and radiographic investigation to determine the nature of the aberrancy. The evaluation of a malfunctioning pulmonary artery catheter (PAC) is a frequent occurrence in the intensive care unit and requires careful clinical consideration and radiographic examination.

Current Opinion in Critical Care, 2014

Comprehensive Physiology, 2012

Acute lung injury (ALI) and its most severe form, acute respiratory distress syndrome (ARDS), wer... more Acute lung injury (ALI) and its most severe form, acute respiratory distress syndrome (ARDS), were presciently described nearly two centuries ago by René Laennec, later to be described clinically in the 1950s and 1960s. Substantial advances have been made in understanding the pathogenesis of these forms of permeability pulmonary edema, including Starling forces and cellular transport mechanisms involved in the generation and resolution of this form of lung injury. Functional animal models and clinically applicable case definitions for ALI and ARDS were instrumental in gaining these new insights. Although no specific pharmacological therapies for ALI and ARDS yet exist, outcomes have improved with advancements in respiratory and fluid-based supportive therapies, and methods to prevent the development or exacerbation of lung injury. Newer targeted therapies continue to be tested for efficacy in this condition where mortality rates frequently exceed 30%. In this article, we review the history of the pathophysiology of lung fluid and solute movement and the seminal clinical observations that brought that history to clinical relevance. We review the relevant lung structure and function and the dynamics of edema formation and resolution, and we describe the related clinical syndromes and the current treatment modalities.

Open Access Journal of Clinical Trials, 2011

Individual intensive care unit (ICU) characteristics including staffing, expertise, continuity, a... more Individual intensive care unit (ICU) characteristics including staffing, expertise, continuity, and team structure, have been associated with patient outcomes. Separately, some aspects of care in ICUs have been implemented through treatment protocols. The United States Critical Illness and Injury Trials Group-Critical Illness Outcomes Study (USCIITG-CIOS) was designed to determine whether the extent of protocol use in ICUs is associated with hospital survival in a large number of US ICUs. Here, we describe the study protocol and analysis plan approved by the USCIITG-CIOS steering committee. USCIITG-CIOS is a prospective, observational, ecological, multicentered study of mixed ICUs in the US. The data to be collected include organizational information for the ICU (eg, protocol availability and utilization, multidisciplinary staffing assessment), and patient level information (eg, demographics, acute and chronic medical conditions). The primary outcome is all-cause hospital mortality, with the objective being to determine whether there is an association between protocol number and hospital mortality for ICU patients. USCIITG-CIOS is powered to detect a 3% difference in crude hospital mortality between high-protocol and low-protocol use ICUs, dichotomized according to protocol number at the median. The analysis will utilize multivariable regression approaches to adjust for outcome clustering by ICU, with secondary linear analysis of protocol number and mortality and a variety of a priori planned ancillary studies. We anticipate at least 60 ICUs participating in USCIITG-CIOS to enroll approximately 6000 study subjects. USCIITG-CIOS is a multicenter study examining the effect of ICU protocols on patient outcomes. These results will inform our understanding of the relationship between protocol availability, use, and patient outcomes in the ICU. Given the shortage of intensivists worldwide, the results of USCIITG-CIOS can be used to promote more effective and reproducible ICU care and outcomes.

Open Access Journal of Clinical Trials, 2011

Hepatology, 2005

Skip to Main Content. ...

Critical Care Medicine, 2006

Sepsis is an increasingly common and lethal medical condition that occurs in people of all ages. ... more Sepsis is an increasingly common and lethal medical condition that occurs in people of all ages. The influence of age on sepsis risk and outcome is incompletely understood. We sought to determine the independent effect of age on the incidence, severity, and outcome of adult sepsis. Longitudinal observational study using national hospital discharge data. Approximately 500 geographically separated nonfederal acute care hospitals in the United States. Patients were 10,422,301 adult sepsis patients hospitalized over 24 yrs, from 1979 to 2002. None. Incident sepsis cases were age adjusted and characterized by demographics, sources and types of infection, comorbid medical conditions, and hospital discharge status. Elderly patients (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or = 65 yrs of age) accounted for 12% of the U.S. population and 64.9% of sepsis cases, yielding a relative risk of 13.1 compared with younger patients (95% confidence interval, 12.6-13.6). Elderly patients were more likely to have Gram-negative infections, particularly in association with pneumonia (relative risk, 1.66; 95% confidence interval, 1.63-1.69) and to have comorbid medical conditions (relative risk, 1.99; 95% confidence interval, 1.92-2.06). Case-fatality rates increased linearly by age; age was an independent predictor of mortality in an adjusted multivariable regression (odds ratio, 2.26; 95% confidence interval, 2.17-2.36). Elderly sepsis patients died earlier during hospitalization, and elderly survivors were more likely to be discharged to a nonacute health care facility. The incidence of sepsis is disproportionately increased in elderly adults, and age is an independent predictor of mortality. Compared with younger sepsis patients, elderly nonsurvivors of sepsis die earlier during hospitalization and elderly survivors more frequently require skilled nursing or rehabilitative care after hospitalization. These findings have implications for patient care and health care resource prioritization and provide insights for expanded scientific investigations and potential patient interventions.

Critical Care, 2008

Sepsis is one of the most common conditions encountered in the intensive care unit and is the 10t... more Sepsis is one of the most common conditions encountered in the intensive care unit and is the 10th leading cause of death overall in the United States. Both long-term survival and health-related quality of life are reduced in survivors of sepsis, yet there is little knowledge of the effect of sepsis-specific interventions on either long-term survival or health-related quality of life. The present article discusses the importance of studying health-related quality of life as it relates to sepsis management strategies, particularly in the context of pharmacologic therapy with recombinant human activated protein C.

Chest, 2008

Methods-Two hundred eighty-eight consecutive patients with sepsis-induced ALI from 14 ICUs at fou... more Methods-Two hundred eighty-eight consecutive patients with sepsis-induced ALI from 14 ICUs at four hospitals in Baltimore,MDwere prospectively classified as having a pulmonary vs nonpulmonary source of sepsis. Multiple logistic regression was conducted to evaluate the independent association of a pulmonary vs nonpulmonary source of sepsis with inpatient mortality.

Critical Care, 2009

Introduction Sepsis-induced acute lung injury (ALI) has been reported to have a higher case fatal... more Introduction Sepsis-induced acute lung injury (ALI) has been reported to have a higher case fatality rate than other causes of ALI. However, differences in the severity of illness in septic vs. non-septic ALI patients might explain this finding.

Journal of graduate medical education, 2014

Simulation training is widely accepted as an effective teaching tool, especially for dealing with... more Simulation training is widely accepted as an effective teaching tool, especially for dealing with high-risk situations. We assessed whether standardized, simulation-based advanced cardiac life support (ACLS) training improved performance in managing simulated and actual cardiac arrests. A total of 103 second- and third-year internal medicine residents were randomized to 2 groups. The first group underwent conventional ACLS training. The second group underwent two 2 1/2-hour sessions of standardized simulation ACLS teaching. The groups were assessed by evaluators blinded to their assignment during in-hospital monthly mock codes and actual inpatient code sheets at 3 large academic hospitals. Primary outcomes were time to initiation of cardiopulmonary resuscitation, time to administration of first epinephrine/vasopressin, time to delivery of first defibrillation, and adherence to American Heart Association guidelines. There were no differences in primary outcomes among the study arms a...

Background: Sepsis represents a substantial health care burden, and there is limited epidemiologi... more Background: Sepsis represents a substantial health care burden, and there is limited epidemiologic information about the demography of sepsis or about the temporal changes in its incidence and outcome. We investigated the epidemiology of sepsis in the United States, with specific examination of race and sex, causative organisms, the disposition of patients,
and the incidence and outcome.

Methods: We analyzed the occurrence of sepsis from 1979 through 2000 using a nationally representative sample of all nonfederal acute care hospitals in the United States. Data on
new cases were obtained from hospital discharge records coded according to the International Classification of Diseases, Ninth Revision, Clinical Modification.

Results: Review of discharge data on approximately 750 million hospitalizations in the United States over the 22-year period identified 10,319,418 cases of sepsis. Sepsis was more
common among men than among women (mean annual relative risk, 1.28 [95 percent confidence interval, 1.24 to 1.32]) and among nonwhite persons than among white persons
(mean annual relative risk, 1.90 [95 percent confidence interval, 1.81 to 2.00]). Between 1979 and 2000, there was an annualized increase in the incidence of sepsis of 8.7 percent, from about 164,000 cases (82.7 per 100,000 population) to nearly 660,000
cases (240.4 per 100,000 population). The rate of sepsis due to fungal organisms increased by 207 percent, with gram-positive bacteria becoming the predominant pathogens after 1987. The total in-hospital mortality rate fell from 27.8 percent during the
period from 1979 through 1984 to 17.9 percent during the period from 1995 through 2000, yet the total number of deaths continued to increase. Mortality was highest among
black men. Organ failure contributed cumulatively to mortality, with temporal improvements in survival among patients with fewer than three failing organs. The average length of the hospital stay decreased, and the rate of discharge to nonacute care medical facilities increased.

Conclusions: The incidence of sepsis and the number of sepsis-related deaths are increasing, although the overall mortality rate among patients with sepsis is declining. There are also disparities among races and between men and women in the incidence of sepsis. Gram-positive bacteria and fungal organisms are increasingly common causes of sepsis.

International journal of cardiology, 2015

A low testosterone level in men is associated with increased adiposity, insulin resistance, and d... more A low testosterone level in men is associated with increased adiposity, insulin resistance, and dyslipidemia. Whether low testosterone level is associated with arterial stiffness and endothelial and microvascular dysfunction remains unknown and was investigated in this study. Serum testosterone was measured in 237 healthy men aged 50years (SD 12). Endothelial and microvascular function were assessed as brachial artery flow-mediated dilation (FMD) and digital reactive hyperemia index (RHI), respectively. Arterial stiffness was evaluated by tonometry-derived pulse wave velocity (PWV) and central augmentation index (AIX). Mean total testosterone level was 16.3nmol/L (SD 6.11) and 25% of subjects had low levels (<12.0nmol/L). Testosterone level correlated positively with RHI (r=0.24, p<0.001) and inversely with AIX (r=-0.14, p=0.033) but not with FMD or PWV, indicating impaired microvascular hyperemia and arterial elasticity with lower testosterone levels. After multivariate adjus...

The American Journal of Emergency Medicine, 2015

The British journal of nutrition, Jan 16, 2015

Vitamin D deficiency is highly prevalent in the US population and is associated with numerous dis... more Vitamin D deficiency is highly prevalent in the US population and is associated with numerous diseases, including those characterised by inflammatory processes. We aimed to investigate the link between vitamin D status and anaemia, hypothesising that lower vitamin D status would be associated with increased odds of anaemia, particularly anaemia with inflammation. A secondary aim was to examine the effects of race in the association between vitamin D status and anaemia. We conducted a cross-sectional analysis in a cohort of generally healthy adults in Atlanta, GA (n 638). Logistic regression was used to evaluate the association between vitamin D status and anaemia. Serum 25-hydroxyvitamin D (25(OH)D) < 50 nmol/l (compared to 25(OH)D ≥ 50 nmol/l) was associated with anaemia in bivariate analysis (OR 2·64, 95 % CI 1·43, 4·86). There was significant effect modification by race (P= 0·003), such that blacks with 25(OH)D < 50 nmol/l had increased odds of anaemia (OR 6·42, 95 % CI 1·8...

PloS one, 2015

To identify patient characteristics associated with low serum 25-hydroxyvitamin D (25(OH)D) conce... more To identify patient characteristics associated with low serum 25-hydroxyvitamin D (25(OH)D) concentrations in the medical intensive care unit (ICU) and examine the relationship between serum 25(OH)D and the risk for hospital-acquired infections. This is a prospective observational cohort of adult patients admitted to the medical ICU at an urban safety net teaching hospital in Atlanta, Georgia from November 1, 2011 through October 31, 2012 with an anticipated ICU stay ≥ 1 day. Phlebotomy for serum 25(OH)D measurement was performed on all patients within 5 days of ICU admission. Patients were followed for 30 days or until death or hospital discharge, whichever came first. Hospital-acquired infections were determined using standardized criteria from review of electronic medical record. Among the 314 patients analyzed, 178 (57%) had a low vitamin D at a serum 25(OH)D concentration < 15 ng/mL. The patient characteristics associated with low vitamin D included admission during winter m...