Data collection
At baseline, both demographic and clinical variables were collected for
each patient. Severity was assessed using the PSI scale (pneumonia
severity index)18. Comorbidity was collected using the
Charlson comorbidity index19 and autonomy in
activities of daily living was measured using the Katz
index20. Vital signs were collected daily to assess
clinical stability. Clinical cure and symptoms of pneumonia were
assessed using a validated questionnaire21. Originally
follow-up for all patients took place for up to 30 days, this period was
extended to one year in this new study.
The main outcome variables that this study assessed were mortality at 90
days, 180 days, and 1 year, as well as new admissions that took place
after the 30-day clinical trial follow-up and up to 1 year of index
admission. Similarly, the occurrence of cardiovascular events was
assessed during that same period of time, defined as the occurrence of
hypertension, cardiac arrhythmia, valvulopathy, heart failure, coronary
heart disease, decompensation of previous heart disease, intermittent
claudication, thrombosis, embolism or stroke. The principal investigator
at each hospital reviewed the medical records to confirm the occurrence
of complications, in addition to conducting phone consultations when
considered necessary. Patients or the public were not involved in the
design, or conduct, or reporting, or dissemination plans of our
research.
On the other hand, a subanalysis was carried out in one of the
hospitals, where biomarker levels were measured at admission, at 5 days
and at 30 days. PCR levels quantified by immunoturbidimetry with an
analytical sensitivity of 1 mg/L were analyzed. PCT was analyzed via
electrochemiluminescence, with an analytical sensitivity of 0.02 ng/mL
and 5 pg/mL respectively. On the other hand, ProADM was analyzed via
sandwich immunoassay using TRACE (time-resolved amplified cryptate
emission) technology with an analytical sensitivity of 0.05 nmol/L.