Table 2.

Correlates of anti-S1 IgG levels after COVID-19 vaccination in unadjusted and multivariable adjusted analyses

	Unadjusted	Multivariable-adjusted
Correlates	Estimated mean percent difference in anti-S1 IgG level (95% confidence interval)	P-value	Estimated mean percent difference in anti-S1 IgG level (95% confidence interval)	P-value
Age
Less than 65 years	0.0 (ref)		0.0 (ref)
65–79 years	−28.9 (−34.5 to −22.7)	6.32e10−16	−20 (−25.5 to −14)	1.19e10−9
80 years and greater	−28.2 (−34.6 to −21.1)	6.13e10−12	−40.2 (−45.1 to −34.8)	1.45e10−31
Sex
Female	0.0 (ref)		0.0 (ref)
Male	−23.9 (−28.8 to −18.6)	1.39e10−15	−21.9 (−26.1 to −17.6)	1.40e10−18
Race/ethnicity
Non-Hispanic white	0.0 (ref)		0.0 (ref)
American Indian or Alaskan Native	22.1 (−3.5 to 54.8)	0.10	−26.2 (−40.3 to −8.8)	0.005
Asian	30.0 (7.3 to 57.5)	0.007	35 (15.6 to 57.8)	1.57e10−4
Black	1.3 (−7.1 to 10.6)	0.77	4.4 (−3.1 to 12.4)	0.26
Hispanic	2.6 (−27.7 to 45.8)	0.88	10 (−17.1 to 45.8)	0.51
Education attainment
College or beyond	0.0 (ref)		0.0 (ref)
Less than high school	12.9 (−5.1 to 34.2)	0.17	0.5 (−12.7 to 15.7)	0.94
High school	5.9 (−2.7 to 15.1)	0.18	−0.4 (−7 to 6.7)	0.90
Some college	−15.6 (−22.7 to −7.9)	1.49e10−4	−1.4 (−8.1 to 5.9)	0.70
Smoking history
Never	0.0 (ref)		0.0 (ref)
Former	−12.3 (−18.1 to −5.9)	2.27e10−4	−9.7 (−14.8 to −4.3)	5.72e10−4
Current	−17.6 (−26.8 to −7.0)	0.002	−19.3 (−26.9 to −11.0)	1.81e10−5
Body mass index
<25 kg/m2	0.0 (ref)		0.0 (ref)
25–29.9 kg/m2	3.4 (−5.1 to 12.6)	0.44	6.8 (−0.3 to 14.6)	0.06
30–34.9 kg/m2	−0.8 (−10.1 to 9.3)	0.87	3.3 (−4.7 to 11.9)	0.44
>35 kg/m2	−10.3 (−19.9 to 0.4)	0.06	−12.0 (−20.0 to −3.1)	0.009
Diabetes
No	0.0 (ref)		0.0 (ref)
Yes	−21.0 (−27.4 to −14.1)	3.56e10−8	−12.7 (−18.7 to −6.3)	1.79e10−4
Hypertension
No	0.0 (ref)		0.0 (ref)
Yes	−17.1 (−22.4 to −11.3)	3.78e10−8	−3.9 (−9.2 to 1.7)	0.17
Cardiovascular disease
No	0.0 (ref)		0.0 (ref)
Yes	−23.7 (−35.1 to −10.4)	0.003	−6.8 (−15.6 to 3.0)	0.17
Chronic kidney disease
No	0.0 (ref)		0.0 (ref)
Yes	−7.7 (−27.8 to 17.9)	0.52	−10.2 (−25.8 to 8.7)	0.27
Asthma
No	0.0 (ref)		0.0 (ref)
Yes	−12.2 (−24.0 to 1.4)	0.08	−7.6 (−16.5 to 2.2)	0.13
Chronic obstructive pulmonary disease
No	0.0 (ref)		0.0 (ref)
Yes	−29.4 (−38.9 to −18.5)	1.49e10−5	−18.3 (−26.8 to −8.7)	5.69e10−4
Log-transformed anti-N MFI (per 1-unit increment)	42.2 (38.3 to 46.2)	1.50e10−129	37.4 (33.2 to 41.8)	1.01e10−64
COVID-19 infection prior to serosurveycollection
No infection	0.0 (ref)		0.0 (ref)
Infection prior to vaccine-not hospitalized	52.3 (38.0 to 68.0)	4.40e10−16	58.7 (44.5 to 74.2)	2.42e10−20
Infection prior to vaccine-hospitalized	67.0 (35.4 to 106.1)	4.90e10−6	80.9 (51.1 to 116.4)	2.32e10−9
Infection after vaccine	90.4 (57.6 to 130.0)	3.40e10−9	−0.7 (−17.2 to 19.2)	0.94
COVID-19 vaccine type
BNT162b2 mRNA (Pfizer-BioNTech)	0.0 (ref)		0.0 (ref)
mRNA-1273 (Moderna)	77.9 (66.7 to 89.8)	1.06e10−66	90.4 (80.6 to 100.6)	5.19e10−123
Time between vaccine and serosurvey collection (per 30 days)	−26.4 (−27.7 to −25.1)	1.35e10−239	−17.7 (−19.7 to −15.8)	3.40e10−58

MFI median fluorescence intensity.

Chronic kidney disease defined as estimated glomerular filtration rate below 45 mL/min/1.73 m.

Multivariable adjusted results arise from a linear regression model including all variables present in this table.

Statistical significance was assessed using two-sided tests. P-values are reported without adjustment for multiple comparisons.

Results from 6245 C4R participants with serology results from February 2021 through August 2022.