Risk perception and knowledge of COVID-19 in patients with celiac disease

Table 1 Demographic characteristics of study population

Demographic	CeD, n = 10737
Age (years), median (IQR)	41 (28-57)
Gender, n (%)	10646 (99.2)
Male	1575 (14.8)
Female	9017 (84.7)
CeD diagnosis, n (%)	10570 (98.4)
Bloodwork1	1304 (12.1)
Biopsy	1334 (12.4)
Bloodwork + biopsy	7506 (69.9)
Unsure	426 (4.0)
Years since diagnosis, median (IQR)	7 (3-13)
Member of celiac association, n (%)	2766 (25.8)
Diet, n (%)
Unrestricted	61 (0.6)
Other restrictions-non gluten	29 (0.3)
GFD-sometimes	118 (1.1)
GFD-most of the time	283 (2.6)
GFD-rare intentional gluten	418 (3.9)
GFD-rare accidental gluten	1566 (14.6)
GFD-possible cross-contamination	1136 (10.6)
Strict GFD	7052 (65.7)
Years diet restriction, Median (IQR)	7 (3-12)
Any household member following GFD, n (%)	2688 (25.0)
Some members	1949 (18.2)
All members	409 (3.8)
Other	221 (2.1)
Management of CeD symptoms, n (%)
Well controlled	7336 (68.3)
Symptoms < 2 mo	2362 (22.0)
Symptoms > 2 mo	938 (8.7)
Travel outside of the country2, n (%)	202 (1.9)
Contact with COVID-19 positive, n (%)	175 (1.6)
Tested for COVID-19, n (%)	478 (4.5)
Fever2, n (%)	252 (2.3)
Respiratory symptoms2, n (%)	1124 (10.5)
Hospitalizations for respiratory infection2, n (%)	21 (0.2)
Comorbidities, n (%)
Chronic lung condition	708 (6.6)
Chronic heart condition	376 (3.5)
Diabetes	413 (3.8)
Receiving steroids	322 (3.0)
Receiving immune suppressive medications	393 (3.7)
Pregnancy, n (%)	96 (0.9)
Information about COVID-19 in celiac disease
Internet	2942 (27.4)
My doctor	291 (2.7)
Other healthcare providers	313 (2.9)
Celiac association website	2465 (23.0)
Other	731 (6.8)

¹Bloodwork includes celiac disease-specific serology anti-tissue transglutaminase immunoglobulin (Ig) A, and/or anti-deaminated gliadin IgA/IgG, and/or anti-endomysial antibodies IgA.

²In the last month. CeD: Celiac disease; IQR: Interquartile range; GFD: Gluten-free diet; COVID-19: Coronavirus disease 2019.

Table 2 Relationship between celiac association membership and coronavirus disease 2019 risk perceptions in patients with celiac disease

Member of a celiac association	CeD respondents, n = 7296	Respondents with high COVID-19 risk perceptions	P value
Yes	2766	1368 (49.5)	< 0.0001
No	4530	2600 (57.4)

CeD: Celiac disease; COVID-19: Coronavirus disease 2019.

Table 3 Country-specific risk perceptions of contracting coronavirus disease 2019 in patients with celiac disease

Country	Infection rate1	ORs for contracting COVID-19 (CeD vs controls)	95%CI	CeD patients believing they are more susceptible to COVID-19, n (%)
Argentina	0.14	1.41	0.48-4.12	2637 (62.9)
Canada	0.04	0.80	0.31-2.01	1962 (52.1)
Australia	0	1.92	0.03-99.21	449 (67.3)
New Zealand	0	0.88	0.01-43.32	295 (65.0)
Spain	0.21	0.73	0.21-2.57	85 (19.1)
United States	0.16	3.28	0.61-17.44	304 (73.1)
Uruguay	0	0.24	0.01-6.68	78 (23.3)
Italy	0	0.27	0.01-6.37	85 (41.5)
Mexico	0.6	1.50	0.15-14.42	62 (42.8)
Other2	0.17	0.70	0.08-6.22	62 (68.1)

¹Infection rate: Positive coronavirus disease 2019 test over total tested.

²Full list of other countries can be found in Supplementary Table 1 in the Supplementary material. ORs: Odds ratios; CeD: Celiac disease; COVID-19: Coronavirus disease 2019.

Table 4 Logistic regression analysis of coronavirus disease 2019 risk perception in patients with celiac disease

	Risk perception
	Crude [OR (95%CI)]	P value	Adjusted1 [OR (95%CI)]	P value
Older age	0.99 (0.99-0.99)	0.012	0.99 (0.99-0.99)	< 0.001
Sex (M)	0.84 (0.76-0.93)	0.001	0.84 (0.75-0.93)	0.001
Strict GFD	0.88 (0.81-0.95)	0.002	0.89 (0.82-0.96)	0.007
Comorbidities2	1.29 (1.17-1.43)	< 0.001	1.37 (1.22-1.54)	< 0.001
Use of corticosteroids or immunosuppressants	1.11 (0.91-1.37)	0.28	0.86 (0.68-1.08)	0.19

¹By all variables listed.

²Comorbidities includes chronic lung conditions, chronic heart conditions, and diabetes. GFD: Gluten-free diet; OR: Odds ratio.