Predictors of In-Hospital Mortality in Older Inpatients with Suspected Infection

OBJECTIVES

To determine the rate and predictors of death in older individuals with suspected infection at any time during hospital stay in a geriatric acute ward and the prognostic ability of different tools [quick Sequential (Sepsis-related) Organ Failure Assessment (qSOFA), Modified and National Early Warning Scores (MEWS) and (NEWS)] in such population.

DESIGN

Prospective observational single-center cohort study.

SETTING AND PARTICIPANTS

Among patients admitted to an acute geriatric unit of an Italian University Hospital with at least 1 sepsis risk factor, all subjects with suspected infection at admission or during hospital stay (defined as antibiotic prescription and associated culture test) were considered.

METHODS

A geriatric assessment including comorbidity and social, functional, and cognitive status was performed for each patient. Clinical parameters were evaluated at least twice daily throughout hospital stay; qSOFA, MEWS, and NEWS were derived, with positive cutoffs set at ≥2, ≥5, and ≥7, respectively.

RESULTS

Among 305 older inpatients (median age 86.0 years, 49.2% female), 21% died during hospital stay. Sepsis was diagnosed in 31.8% of the overall sample and in 64.1% of deceased patients. Deceased patients showed a significantly higher prevalence of prior institutionalization, functional dependence, cognitive impairment, and multimorbidity. The prognostic accuracy of the qSOFA score at infection onset was only fair (area under the receiver operating characteristic curve 0.72; 95% CI, 0.65-0.79, P < .001) and comparable with that of MEWS and NEWS. After multivariable analysis, in-hospital death was positively associated with male sex [odds ratio (OR), 2.11; 95% CI, 1.01-4.44; P = .048] and abnormal white blood cells count (OR, 4.93; 95% CI, 2.36-10.29; P < .001), platelet count (OR, 2.61; 95% CI, 1.10-6.16; P = .029) and serum creatinine (OR, 2.70; 95% CI, 1.30-5.61; P = .008), along with any of the score considered, and negatively associated with autonomy in instrumental activities (OR, 0.78; 95% CI, 0.68-0.90; P < .001).

CONCLUSIONS

Prognosis in older inpatients with infection or sepsis appears to be determined both by the geriatric characteristics and by the severity of the acute event, expressed by recommended tools and blood test results.

Comparison of Diagnostic Accuracies of qSOFA, NEWS, and MEWS to Identify Sepsis in Older Inpatients With Suspected Infection

OBJECTIVES

To determine and compare the accuracies of the quick Sequential (Sepsis-related) Organ Failure Assessment (qSOFA) and Modified and National Early Warning Scores (NEWS and MEWS) to identify sepsis in older inpatients with suspected infection.

DESIGN

Prospective diagnostic accuracy study.

SETTING AND PARTICIPANTS

Patients admitted to an acute geriatric unit of an Italian University Hospital with at least one sepsis risk factor and suspected infection defined as antibiotic prescription and associated culture test during hospital stay.

METHODS

Sepsis diagnosis was defined as the presence on discharge documents of International Classification of Diseases, Ninth revision, Clinical Modification codes for severe sepsis, septic shock, or for infection and acute organ disfunction. For each patient, clinical parameters were evaluated at least twice daily throughout hospital stay; qSOFA, NEWS, and MEWS were derived, and worst scores recorded. Positive cutoffs were set at ≥2, ≥7, and ≥5, respectively. Sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively), and positive and negative likelihood ratios, as well as areas under the receiver operating characteristic curve (AUROCs) were calculated.

RESULTS

Among 230 geriatric patients with suspected infection at risk for sepsis (median age 86 years, 49% women), 30.9% had a sepsis diagnosis. A qSOFA ≥2 was recorded in 111 (48.3%) patients, a MEWS ≥5 in 65 (28.3%), and a NEWS ≥7 in 115 (50.0%). The qSOFA showed the highest sensitivity [81.7%, 95% confidence interval (CI) 71.7%-89.5%], but low specificity (66.7%, 95% CI 59.1%-73.7%), resulting in a high NPV (89.1%; 95% CI 82.7%-93.8%) and poor PPV (52.3%, 95% CI 43.0%-61.4%). The AUROC for qSOFA was 0.76 (95% CI 0.69-0.83), comparable with that of NEWS (0.74, 95% CI 0.67-0.81, P = .44), but significantly higher than that of MEWS (0.70, 95% CI 0.63-0.77, P = .04).

CONCLUSIONS AND IMPLICATIONS

Repeated qSOFA determinations are useful to rule out sepsis in geriatric inpatients with suspected infection, but poorly support its diagnosis due to low specificity. More complex MEWS and NEWS do not perform better. Implementation of clinical scores to reliably identify sepsis in older patients is urgently needed.