. 2022 Mar 23;91(6):756–771. doi: 10.1002/ana.26339

TABLE 6.

Observed to Expected Rates of Neurological events Reported after COVID Vaccination Compared to Rates of Neurological Events During the Acute Phase of SARS‐CoV‐2 Infection. Person‐years of Observation for all COVID Vaccines

Adverse event	Characteristic	All COVID vaccines^ (n = 306,907,697 doses)	Pfizer (n = 166,981,930 doses)	Moderna (n = 128,084,622 doses)	Janssen (n = 11,606,202 doses)
Any neurological event	Observed N	105,214	44,896	42,368	17,622
	Expected N (post‐COVID rate 69,416¹⁴‐324,109¹⁹/100,000 person‐yr)	13,908,927‐64,941,552	7,189,668‐33,568,956	5,803,962‐27,099020	915,298‐4,273,575
	O:E, (95% CI)	0.002 (0.002–0.002) to 0.008 (0.008–0.008)	0.001 (0.001–0.001) to 0.006 (0.006–0.006)	0.002 (0.002–0.002) to 0.007 (0.007–0.007)	0.004 (0.004–0.004) to 0.02 (0.02–0.02)
Encephalo‐pathy	Observed N	3,180	1,303	1,286	579
	Expected N (post‐COVID rate 35,395¹⁴‐204,844¹⁹/100,000 person‐yr)	7,092,176‐41,044,572	3,666,019‐21,216,361	2,959,446‐17,127,211	466,711‐2,700,999
	O:E, (95% CI)	0.0004 (0.0004–0.0005) to 0.00008 (0.00008–0.00008)	0.0004 (0.0003–0.0004) to 0.00006 (0.00006–0.00006)	0.0004 (0.0004–0.0005) to 0.00008 (0.00007–0.00008)	0.001 (0.001–0.001) to 0.0002 (0.0002–0.0002)
Guillain‐Barre Syndrome	Observed N	265	115	87	61
	Expected N (post‐COVID rate 344¹⁴/100,000 person‐yr)	68,847	35,588	28,729	4,531
	O:E, (95% CI)	0.004 (0.003–0.004)	0.003 (0.003–0.004)	0.003 (0.002–0.004)	0.013 (0.01–0.02)
Bell's Palsy	Observed N	1846	917	809	117
	Expected N (post‐COVID rate 82¹⁷/100,000 person‐yr)	16,430	8,493	6,856	1,081
	O:E, (95% CI)	0.11 (0.11–0.12)	0.11 (0.10–0.11)	0.12 (0.11–0.13)	0.11 (0.09–0.13)
Headache	Observed N	41,710	16,128	17,260	8,163
	Expected N (post‐COVID rate 97,358²⁰/100,000 person‐yr)	19,507,599	10,083,679	8,140,194	1,284,727
	O:E, (95% CI)	0.002 (0.002–0.002)	0.002 (0.002–0.002)	0.002 (0.002–0.002)	0.006 (0.006–0.006)
Anosmia/dysgeusia	Observed N	1932	983	712	232
	Expected N (post‐COVID rate 23,621²⁰/100,000 person‐yr)	4,732,934	2,446,502	1,974,974	311,458
	O:E, (95% CI)	0.0004 (0.0004–0.0004)	0.0004 (0.0004–0.0004)	0.0004 (0.0003–0.0004)	0.0007 (0.0007–0.0008)
Cerebral venous thrombosis	Observed N	128	40	34	53
	Expected N (post‐COVID rate 112¹⁸/100,000 person‐yr)	22,441	11,600	9,364	1,477
	O:E, (95% CI)	0.006 (0.005–0.007)	0.003 (0.002–0.005)	0.004 (0.003–0.005)	0.04 (0.03–0.05)
Ischemic Stroke	Observed N	1704	688	750	255
	Expected N (post‐COVID rate 6987.4¹⁴/100,000 person‐yr)	1,400,064	723,707	584,223	92,133
	O:E, (95% CI)	0.001 (0.001–0.001)	0.001 (0.001–0.001)	0.001 (0.001–0.001)	0.003 (0.002–0.003)
Intracerebral Hemorrhage	Observed N	173	77	60	36
	Expected N (post‐COVID rate 2290.9¹⁴/100,000 person‐yr)	459,027	237,276	191,544	30,207
	O:E, (95% CI)	0.0004 (0.0003–0.0004)	0.0003 (0.0003–0.0004)	0.0003 (0.0002–0.0004)	0.001 (0.0008–0.001)
Subarachnoid Hemorrhage	Observed N	72	30	22	10
	Expected N (post‐COVID rate 343.6¹⁴/100,000 person‐yr)	68,847	35,588	28,729	4,531
	O:E, (95% CI)	0.001 (0.0008–0.001)	0.0008 (0.0006–0.001)	0.0008 (0.0005–0.001)	0.002 (0.001–0.004)
Seizure	Observed N	1933	905	680	340
	Expected N (post‐COVID rate 4,387¹⁹–8477¹⁴/100,000 person‐yr)	878,956‐1,698,454	454,341‐877,949	366,774‐708,737	57,841‐111,769
	O:E, (95% CI)	0.001 (0.001–0.001) to 0.002 (0.002–0.002)	0.001 (0.001–0.001) to 0.002 (0.002–0.002)	0.001 (0.001–0.001) to 0.002 (0.002–0.002)	0.003 (0.003–0.003) to 0.006 (0.005–0.007)

O:E = observed to expected ratio; Bold represents O:E >1; ^note that the sum of events for Pfizer, Moderna and Janssen does not equal the total number of events because some entries did not specify COVID vaccine manufacturer.