SCIENTIFIC REPORT CHAPTER 1. INTRODUCTORY CHAPTER
CHAPTER 4. PATIENT SURVEY:
3.3 Data collection process
The survey was launched on the 27th of January 2021 and ran until the 14th of February 2021. The call was relaunched approximately one week after the start of the survey to reach as many people as possible. We also asked the patient organisations LUSS and VPP to re-launch their invitation to their networks. The call was also mentioned by the Sciensano representative during the daily press briefing of the national COVID crisis center (date:
09/02/2021) and was picked up by general media (online newspapers).
3.4 Analysis
Subgroup analyses were performed to more accurately assess the needs of patients with long COVID. Subgroup variables were: hospitalisation status (hospitalised versus non-hospitalised), duration of COVID-19 symptoms groups (short: 4 weeks to 3 months; mid: 3 to 6 months; long: more than 6 months) and age of respondents (children (<18 years) versus others).
Individual subjective health states described with the EQ-5D-5L tool (e.g.
11111 for perfect health and 55555 for the worst health conditions) were valued using the most recent Belgian valuation set (2021).198
Statistical analysis performed and software used
ANOVA one-way and Tukey post-hoc pairwise comparisons were used to compare average Delta (VAS before-VAS after COVID), Beta (EQ-5D-5L before-EQ-5D-5L after) and the number of symptoms by duration of symptoms groups (short: 4 weeks to 3 months, mid: 3 to 6 months, long: >
6months). Univariate and multivariate linear regression analysis were used to estimate the factors significantly associated with Beta. The factors introduced in the regression analysis were: gender (male/female), language (French/Dutch), region (Brussels, Flanders and Wallonia), age group (French <18,18-30,31-40,41-50,51-60, >60; Dutch <18,18-24,25-44,45-64,65-74, >74), education level (no diploma/primary, lower secondary, upper secondary, short type, long type), paid job (Yes/No), health job (Yes/No), number of comorbidities, duration of COVID symptoms groups (short, mid, long), Delta, hospitalisation (Yes/No), emergency care (Yes/No), number of long COVID symptoms, type of long COVID symptoms (breathing difficulties (Yes/No), fatigue (Yes/No), lack of energy (Yes/No), concentration problem (Yes/No), headache (Yes/No), difficulty or loss of memory (Yes/No), muscle pain and weakness (Yes/No), joint pain (Yes/No), insomnia (Yes/No)), long COVID treatment (Yes/No), inability to work (Yes/No), financial impact of long COVID (Yes/No), help for daily activities (Yes/no), needs (to talk to other people (Yes/No), to health professional (Yes/No), to other patients (Yes/No), need for additional help (Yes/No), for administrative support (Yes/No), for religious support (Yes/No)) and type of long COVID information received (none received, not clear at all, not very clear, fairly clear and very clear). Paired t-tests were applied to compare average Delta and Beta by hospitalisation status. T-tests (unequal variance) were used to compare the number of reported symptoms by hospitalisation status. Chi-squared tests were applied to compare proportions of comorbidities groups, most commonly reported symptoms, incapacity to work, social support needs, financial impact of COVID-19, back to work status, duration of symptoms (short, mid, long) by hospitalisation status, healthcare utilisation and treatment for long COVID by hospitalisation status and by duration of symptoms groups. The statistical analyses were performed with SAS Entreprise Guide (7.1) and the figures plotted with R Studio (1.4.1106). A p-value below 0.05 was considered as significant.
116 Long COVID – Scientific report KCE Report 344
Open-ended questions analysis
Responses to the open-ended questions were re-coded by theme and grouped to be analysed in a quantitative way. The recoding of the healthcare professions was done based on the medical specialties defined for the question on the use of healthcare professionals. We focused on professionals providing care and/or seeing patients in consultation; other professions such as administrative professions were categorised as 'other'.
For reported comorbidities, open-ended responses were merged with existing categories (i.e. categories proposed in the online questionnaire) and if not possible, new categories were created based on the literature and/or after consultation among researchers. This was the same process for open-ended questions related to symptoms, treatments, side effects and type of health professionals consulted.
Responses to open-ended questions related to tedious treatment, long-term side effects, financial aspects, support needs, network and unmet medical needs were illustrated through quotes (one in each national language if possible).
4 RESULTS
4.1 Description of the participants
4.1.1 Demographic dataAt the end of the online survey, 1 395 participants had fully completed the questionnaire and after applying the exclusion criteria (section 3.2), 1 320 participants were retained for the analysis (33 participants did not live in Belgium, 15 had COVID symptoms for less than four weeks and 31 reported no symptoms of long COVID (4 participants met two exclusion criteria)). The majority of respondents were women (74.8%) and from Flanders (59.0%).
The most represented provinces among the participants were Antwerpen (16.5%), Oost-Vlaanderen (13.0%) and Vlaams-Brabant (13.2%). There was a relatively large proportion of people with a high level of education (non-university higher education (30.5%); university education (25.4%)) and who had paid work before acute COVID-19 (82.0%) (Table 10). Most of the respondents (97.1%) answered the online questionnaire for themselves and only a minority for another adult (1.8%) or a child (1.1%) (Table 10).
Table 10 – Description of the participants in the online survey (n=1 320)
Variable N (%)
Status of the respondent: completing the survey for
Yourself 1 282 (97.1) Another adult 24 (1.8)
A minor 14 (1.1) Gender
Women 987 (74.8) Men 331 (25.1) Other 2 (0.1) Language
Dutch 769 (58.3) French 551 (41.7)
KCE Report 344 Long COVID – Scientific report 117
Region
Flanders 779 (59.0) Wallonia 398 (30.0) Brussels 143 (11.0) Province
Antwerpen 218 (16.5) Vlaams-Brabant 174 (13.2) Oost-Vlaanderen 172 (13.0) Bruxelles 143 (10.8) West-Vlaanderen 115 (8.7)
Liège 113 (8.6) Hainaut 109 (8.3) Limburg 100 (7.6) Brabant Wallon 83 (6.3)
Namur 68 (5.2) Luxembourg 25 (1.9) Paid job
Yes 1 076 (82.0) Education level
No diploma 10 (0.8)
Primary education 18 (1.4)
Lower secondary education or 1st or 2nd level
secondary education 58 (4.4)
Upper secondary education or general secondary
education at the 3rd level 204 (15.5)
Post-secondary non-tertiary 71 (5.4)
Non-university higher education of the short type 403 (30.5)
Academic baccalaureate 95 (7.2)
Non-university higher education of the long type,
master's degree at a university 72 (5.5)
University education, bachelor's, engineer or master's
degree 335 (25.4)
Doctorate with thesis 36 (2.7)
Other diploma 13 (1.0)
I don't know 5 (0.4)
The Dutch-speaking population (n=769) was predominantly female and aged between 25 and 64. Women were also more numerous in all age groups. There were relatively few respondents under 18 (1%) and over 75 (1%) years of age (Figure 3).
118 Long COVID – Scientific report KCE Report 344 Figure 3 – Gender and age distribution of the participants, by language (Dutch (n=769), French (n=551))
KCE Report 344 Long COVID – Scientific report 119
4.1.2 Employment status
More than 80% of the respondents were in paid employment before being infected with SARS-COV-2 and 30% were working in the health sector (38% were nurses). Information on the impact of COVID-19 on
employment status is available in subsection 4.2.2.1.
4.1.3 Existing comorbidities
64% reported no comorbidities prior to COVID-19
Slightly more than 36% of respondents reported having at least one comorbidity before COVID-19. Yet the vast majority of respondents had no (63.7%) comorbidities and 23.9% of the patients reported only one to two comorbidities (Figure 4).
Figure 4 – Number of comorbidities among participants (n=1 320)
Most frequent reported pre-existing co-morbidities
The four most frequently reported comorbidities among patients who reported suffering from comorbidities (n=489) were disease of the locomotor system (bones, joints, muscles) (12.1%), respiratory diseases (10.0%), heart and blood vessel disease (7.6%) and digestive disease (7.2%).
Patients who were hospitalised reported more pre-existing comorbidities
Patients who were hospitalised reported significantly more comorbidities than patients who were not hospitalised (p<0.001). One quarter of the patients who were hospitalised for COVID-19 (26.4%) reported at least three comorbidities while among the non-hospitalised patients, only 10.7%
reported at least three comorbidities (Table 11).
Table 11 – Number of comorbidities, by hospitalisation status (n=1 320) Number of
comorbidities Hospitalised (n=174)
N (%)
Not hospitalised (n=1 146)
N (%)
p-value Total N (%)
None 87 (50.0) 754 (65.8) *** 841 (63.7)
1 to 2 41 (23.6) 269 (23.5) 310 (23.5)
3 to 4 26 (14.9) 91 (7.9) 117 (8.9)
5 or more 20 (11.5) 32 (2.8) 52 (3.9)
** Chi-squared, p<0.001
In the subgroup of patients with the longest duration of COVID-19 symptoms, the number of comorbidities is higher
The number of comorbidities is also significantly related to the duration of the acute COVID-19. The higher the number of comorbidities, the longer the duration of COVID-19. Six percent of the patients who have (had) symptoms of COVID-19 for more than 6 months reported five comorbidities or more vs.. 1.1% and 3.1% in the short and mid duration categories (Table 12).
120 Long COVID – Scientific report KCE Report 344
Table 12 – Number of comorbidities, by COVID-19 duration (n=1 318*) Short
(N=267)
Mid (N=484)
Long (N=567)
p-value Total (N=1 318)
**
None 177 (66.3%) 312 (64.5%) 351 (61.9%) 840 (63.7) 1 to 2 71 (26.6%) 115 (23.8%) 123 (21.7%) 309 (23.4) 3 to 4 16 (6.0%) 42 (8.7%) 59 (10.4%) 117 (8.9) 5 or more 3 (1.1%) 15 (3.1%) 34 (6.0%) 52 (3.9)
**Chi-squared, p=0.01; *Missing duration for two respondents; Short = 4 weeks to 3 months; Mid=3 to 6 months; Long=More than 6 months
Pre-existing co-morbidities in minors with long COVID
In the less than 18 years population (n=16), 13 (81.2%) reported no comorbidities, two (12.5%) reported one to two comorbidities and one (6.3%) reported three to four comorbidities.
4.1.4 Acute COVID-19 episode 4.1.4.1 Test/diagnosis
Small minority without a test or clinical diagnosis of COVID-19
Three percent of the participants (40/1 320) responded that they were not diagnosed or tested positive for COVID-19 at all. For 27.5% of them (n=11), it was because there was no test available at the time of infection.
Eleven percent with a clinical diagnosis but no test
10.7% of the respondents (141/1 320) were diagnosed as positive by a physician based on symptoms, without being tested positive by a PCR-test, blood sample or diagnostic imaging techniques.
Vast majority tested positive for COVID-19
Of those who tested positive (n=1 139), most were tested by a nose swap PCR test only (51.4%) and 22.3% were tested by multiple techniques. Some participants (n=121) responded being tested positive for COVID-19 but did not select any diagnostic technique (Table 13).
Table 13 – Diagnosis techniques among tested positive respondents (n= 1 139)
N (%)
Blood 152 (13.3)
Nose swap PCR 586 (51.4)
Imaging 25 (2.2)
Blood, nose swap PCR and imaging 56 (4.9)
Blood and nose swap PCR 136 (11.9)
Blood and imaging 22 (1.9)
Nose swap PCR and imaging 41 (3.6)
None of the proposed diagnosis techniques 121 (10.6) Finally, 78.3% (1 034/ 1 320) responded “Yes” to the question “Has a doctor or other health care professional confirmed that the symptoms you are currently experiencing (or have experienced) are the result of COVID-19?”
4.1.4.2 COVID-19-related hospitalisation
Table 14 shows the main information reported by the respondents with regard to their hospitalisation in the context of COVID-19. Thirteen percent (174/1 320) of respondents were hospitalised for a duration of less than one week (33.9%), one to two weeks (37.4%) or more than two weeks (28.7%).
Just over thirty percent of those hospitalised were admitted to an intensive care unit and the majority of them (73.6%) had been on respiratory assistance (Table 14).
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Table 14 – Description of hospitalised respondents (n= 174) N (%) Length of stay
1 to 2 weeks 65 (37.4)
< 1 week 59 (33.9)
> 2 weeks 50 (28.7) Intensive care (n=174)
No 121 (69.5) Yes 53 (30.5) Respiratory assistance (n= 53)
Yes 39 (73.6) No 14 (26.4)
4.1.5 Duration COVID-19-related symptoms
Most patients still had symptoms at the time of completion of the questionnaire
1 255 out of 1 320 respondents (95%) still had COVID-19-related symptoms at the time of the online survey. In Figure 5, patients still having symptoms at the time of the survey are shown in red, while those without symptoms are shown in blue.
For those who no longer had symptoms at the time of survey completion, more than 59% (n= 38) reported that their symptoms lasted between 4 weeks and 3 months.
Most patients with ongoing symptoms has symptoms for more than 3 months
For those who still had symptoms, this had been going on for more than 3 months at the time of the survey (37% between 3 and 6 months and 45% 6 months and more).
122 Long COVID – Scientific report KCE Report 344 Figure 5 – Duration of COVID-19-related symptoms, by recovering status
Half of the participants who had been hospitalised in the acute phase of COVID-19 have (had) symptoms for more than 6 months (52.3%). The proportion of hospitalised participants is significantly higher in the mid (3-6 months) and long (>6 months) duration of symptoms groups than in the proportion of non-hospitalised participants (Table 14). However, the duration of symptoms was not significantly related to hospitalisation in the intensive care unit (Table 16).
KCE Report 344 Long COVID – Scientific report 123
Table 15 – Duration of symptoms, by hospitalisation status Hospitalised
N=174 N (%)
Not Hospitalised N=1 144 N (%)
p-value Total N=1 318 N (%)
**
Short (4
weeks-3months) 39 (22.4) 228 (19.9) NS 267
(20.3) Mid (3 to 6 months) 44 (25.3) 440 (38.5) ** 484
(36.7) Long (>6 months) 91 (52.3) 476 (41.6) * 567
(42.0)
*Chi-squared p-value<0.05, ** Chi-squared p-value<0.01, NS=Not significant, Duration is missing for n=2
Table 16 - Duration of symptoms, by hospitalisation in ICU status Hospitalised
ICU N=53 N (%)
Hospitalised not ICU N=121 N (%)
p-value Total N=174 N (%) NS
Short (4
weeks-3months) 7 (13.2) 32 (26.5) 39 (22.4)
Mid (3 to 6 months) 16 (30.2) 28 (23.1) 44 (25.3) Long (>6 months) 30 (56.6) 61 (50.4) 91 (52.3) NS=Not significant (Chi-squared), ICU=Intensive Care Unit