Study population
Health questionnaires were sent out to patients quarterly after
discharge and focused on physical as well as mental well-being.
Demographic information was acquired through a baseline questionnaire
and partly through the MST clinical database. For the current study,
questionnaires completed 6 months after hospital discharge were coupled
via patient study number to the retrospectively collected clinical
patient data and selected for analysis. By combining the two databases
it is possible to determine which patients develop post-COVID-19
syndrome and the nature of the treatments and medications these patients
have undergone while admitted to the hospital. Thus, making it possible
to identify possible associations between drug treatments and the
development of post-COVID-19 syndrome. The combined database consists of
patients 18 years or older that were admitted to the hospital (MST) due
to COVID-19 symptoms confirmed using a polymerase chain reaction (PCR)
test, who have completed the informed consent form and have sufficient
proficiency in the Dutch language.
OutcomesPost-COVID-19 syndrome presence 6 months after hospital discharge was
determined using the following questions out of the Post COVID database.
Question 1: “In general, how would you describe your health at the
moment?”. Question 2: “compared to one year ago, how would you rate
your health in general now?”. Question 3: “during the past 4 weeks, to
what extent has your physical health or emotional problems interfered
with your normal social activities with family, friends, neighbors, or
groups?”. Question 4: “For the following 4 statements regarding
fatigue, please indicate how you have been feeling during the past 2
weeks”. Question 5: “have you felt downhearted or anxious?”. Question
6: “are you occasionally short of breath?”. Using the above-stated
questions, three definitions were created to determine post-COVID-19
syndrome status, each consisting of 4 questions (figure 2 ).
Definition 1 consists of questions 1, 2, 3 and 5. Definition 2 consist
of question 1, 2, 3 and 4. Definition 3 consists of questions 1, 2, 3
and 6. If a patient fit one or more definitions based on the answers
they provided, they were categorized as having post-COVID-19 syndrome. A
combination of the first question being answered with “fair” or
“poor” the second question with “Somewhat worse or much worse now
than one year ago” and the third question with “slightly to very
severe” combined with “mostly true” or “definitely true” for
statements regarding experiencing fatigue and “mostly false” or
“definitely false” for statements regarding being fit of the fourth
question or “slightly to very severe” for the fifth or sixth questions
prompted the patient to be categorized as having developed post-COVID-19
syndrome. Due to the broad nature of the definition of
post-COVID-syndrome, the aforementioned questions were implemented to
encompass the essence and to give body to this definition. The first 3
questions were chosen to capture the burden of post-COVID-19 symptoms
and their effect on the physical, mental, and general health of
patients. While the fourth, fifth and sixth questions are meant to
encompass common symptoms of post-COVID-19 syndrome [22,23].