Background: Infectious disease-related factors that may contribute to or complicate falls have received relatively little attention in the literature. Specifically, the prevalence of coexisting systemic infections (CSIs) in patients presenting with a fall and admitted to the hospital has not been previously reported. We, herein, describe the scope and characteristics of CSIs in hospitalized patients presenting with a fall with the goal of identifying factors that may lead to their earlier recognition and treatment.

Methods: This was a retrospective study involving patients presenting with the chief complaint of fall through the emergency department (ED) of Massachusetts General Hospital (MGH), a teaching tertiary care institution in Boston, from January 1, 2015 through September 30, 2015. Exclusion criteria included age < 18 y, fall caused by seizure, physical trauma or accident, and fall > 6 days prior to ED visit. “Mechanical” fall was defined as a fall caused by tripping over an object, slipping, or loss of balance or muscle tone without syncope. Systemic inflammatory response syndrome (SIRS) was defined as ≥ 2 of 4 widely-accepted criteria. Diagnosis of CSI was based on clinical, laboratory or radiographic assessment by the providing clinician(s) and treatment with systemic antimicrobials, as indicated, either at the time of or within 48 h of admission. Statistical significance was defined as P <0.05.

Results: Of 2224 fall visits to our ED during the study period, 974 met the exclusion criteria resulting in 1250 evaluable cases in 1178 unique patients; 633 (53.7%) were female. The mean age was 71.4 y (range 18-104 y). CSI was diagnosed in 258 (20.6%) falls, of which 145 (56.2% ) were urinary tract infections, 89 (34.5%) were pneumonia, 8 (3.6%) were skin and soft tissue infections, and 10 (3.9%) were bacteremic. CSI prevalence was highest in the ≥75 y age group (26.2%), vs 18.2% for 50-75 y and 5.4% for < 50 y groups (P<0.001). CSI rates between females and males were not significantly different (21.5% vs 20.0%, respectively). Mechanical falls accounted for 43.2% of all falls with CSI. CSI was not initially suspected to be present or to contribute to the fall by providers in 88 (34.1%) and 168 (65.1%) cases, respectively. Evaluable factors significantly associated with CSI included the inability to get up on own following a fall (85.1 % vs 66.3 %), fall location at home or in an extended care facility (83.7% vs 72.5%), presentation ≥1 day (vs < 1 day) after the fall (35.0% vs 20.7%), onset of new symptoms (eg, weakness or confusion) during the 7 days preceding the fall (57.4% vs 23.7%), absence of fracture (62.8% vs 35.3%), and presence of SIRS (28.8% vs 10.5%) or confusion (24.4% vs 8.5%) on presentation (P<0.001 for all). Temperature and white blood cell counts were normal on presentation in 88.0% and 68.6% of CSI patients, respectively. Patients with CSI had significantly longer duration of hospitalization (mean 9 days vs 6.5 days, P<0.001) and higher in-hospital mortality (7.4% vs 4.1%, P=0.03).

Conclusions: CSI particularly among older patients admitted with fall is not uncommon, is often not suspected on the initial healthcare encounter, and is associated with longer length of stay and higher in-hospital mortality. New symptoms prior to the fall, inability to get up on own, presentation ≥ 1 day after a fall, and presence of SIRS or confusion on presentation may serve as potential clues to CSIs and lead to their earlier recognition and treatment. More studies are needed to further delineate the role of CSIs in causing or complicating falls.