The Clinical Significance of Procalcitonin Elevation in Patients over 75 Years Old Admitted for COVID-19 Pneumonia

Abstract

Aim. To investigate the clinical significance of procalcitonin (PCT) elevation on hospital admission for coronavirus disease-19 (COVID-19) and its association with mortality in oldest old patients ( age > 75 years ). Methods. The clinical records of 1074 patients with chest high-resolution computed-tomography (HRCT) positive for interstitial pneumonia and symptoms compatible for COVID-19, hospitalized in medical wards during the first pandemic wave in a single academic center in Northern Italy, were retrospectively analyzed. All patients had serum PCT testing performed within six hours from admission. Information on COVID-19-related symptoms, comorbidities, drugs, autonomy in daily activities, respiratory exchanges, other routine lab tests, and outcomes were collected. Clinical characteristics were compared across different admission PCT levels and ages. The association of admission PCT with mortality was tested separately in participants aged > 75 and ≤75 years old by stepwise multivariate Cox regression model with forward selection. Results. With increasing classes of PCT levels (<0.05, 0.05-0.49, 0.5-1.99, and ≥2 ng/ml), there was a significant trend ( P < 0.0001 ) towards older age, male gender, wider extension of lung involvement on HRCT, worse respiratory exchanges, and several other laboratory abnormalities. Each incremental PCT class was associated with increased risk of hospital death at multivariate models in subjects older than 75 (hazard ratio for PCT ≥ 2 vs. <0.05 ng/ml: 30.629, 95% confidence interval 4.176-224.645, P = 0.001 ), but not in subjects aged 75 or younger. Conclusions. In patients admitted for COVID-19, PCT elevation was associated with several clinical, radiological, and laboratory characteristics of disease severity. However, PCT elevation was strongly associated with hospital mortality only in oldest old subjects ( age > 75 ).

Routine laboratory parameters, including complete blood count, predict COVID-19 in-hospital mortality in geriatric patients

“…In a recent study on patients admitted for COVID-19, PCT elevation was associated with several clinical, radiological, and laboratory characteristics of disease severity. However, PCT elevation was strongly associated with hospital mortality only in subjects older than 75 years ( Ticinesi et al, 2021 ).…”

Co-Administration of Remdesivir and Azithromycin May Protect against Intensive Care Unit Admission in COVID-19 Pneumonia Requiring Hospitalization: A Real-Life Observational Study

“…However, the majority of severe cases of COVID-19 generally involve older subjects, with several comorbidities and relevant pneumonia extension on chest imaging [ 22 , 34 , 35 ]. Age-related frailty represents a consistent risk factor for adverse outcomes in COVID-19 [ 35 , 36 ], also for the increased risk of bacterial superinfection [ 37 ]. Many older subjects included in our study were excluded from remdesivir treatment because their clinical presentation on admission was not compatible with the criteria of prescription [ 27 ].…”

Laboratory Biomarkers for Diagnosis and Prognosis in COVID-19

“…As for systemic biomarkers of infection, procalcitonin is a predictor of disease severity ( 31 ), and can be useful to guide antimicrobial stewardship ( 32 , 33 ). Another study found an association between procalcitonin and mortality in COVID-19 patients more than 75 years old ( 34 ). Neutrophil count was also predictive of clinical outcome in hospitalized COVID-19 patients ( 35 ), while the neutrophil-to-lymphocyte ratio was strongly associated with severity and mortality in COVID-19 ( 36 ).…”