Risk of Thrombosis Following the First Dose of ChAdOx1 nCoV-19 Vaccine in Patients Undergoing Maintenance Hemodialysis: A Self-Controlled Case Series Study

Figures & data

Figure 1 Schematic illustration of the study design.

Figure 2 Flow chart for selection of cases for the main analysis.

Table 1 Baseline Demographics of Cases Selected for the Self-Controlled Case Series Analysis

Characteristics	Hemodialysis Patients (N = 59)	Non-Dialysis Patients (N = 41)
Age in years, mean (SD)	64.7 (11.6)	67.4 (17.1)
Female sex, N (%)	23 (39.0)	19 (46.3)
Northern location, N (%)	44 (74.6)	34 (82.9)
Body mass index in kg/m^2, mean (SD)	26.6 (5.9)	25.1 (3.7)
Systolic blood pressure in mmHg, mean (SD)	137.3 (25.0)	144.7 (27.7)
Diastolic blood pressure in mmHg, mean (SD)	73.9 (13.2)	85.3 (16.6)
Hypertension, N (%)	28 (47.5)	23 (56.1)
Hyperlipidemia, N (%)	29 (49.2)	18 (43.9)
Atrial fibrillation, N (%)	4 (6.8)	4 (9.76)
Ischemic heart disease, N (%)	25 (42.4)	6 (14.6)
Oral antiplatelets, N (%)	44 (74.6)	17 (41.5)
Statins, N (%)	31 (52.5)	17 (41.5)
Phosphorous in mg/dL, mean (SD)	4.9 (1.6)	3.3 (0.7)
Calcium in mg/dL, mean (SD)	9.5 (0.9)	8.8 (0.6)
Albumin in gm/dL, mean (SD)	3.9 (0.3)	3.7 (0.6)
Triglyceride in mg/dL, mean (SD)	165.7 (145.6)	150.6 (149.3)
Total cholesterol in mg/dL, mean (SD)	158.6 (42.6)	191.2 (33.2)
Platelets in 10^3/μL, mean (SD)	198.3 (67.0)	253.1 (82.1)
Intact parathyroid hormone in pg/mL, mean (SD)	377.0 (355.3)	*
Events in study period
Thrombocytopenia, N (%)	1 (1.7)	8 (19.5)
Venous thromboembolism, N (%)	4 (6.8)	3 (7.3)
Arterial thrombosis, N (%)	3 (5.1)	0 (0)
Cerebral venous sinus thrombosis, N (%)	0 (0)	0 (0)
Ischemic stroke, N (%)	24 (40.6)	23 (56.1)
Myocardial infarction, N (%)	27 (45.8)	7 (17.1)

Note: *Insufficient data to be presented.

Abbreviation: SD, standard deviation.

Table 2 Incident Rate and IRR of Thrombosis Events in Each Risk Period Compared to Periods Not at Risk for ESRD Patients Receiving Chronic Maintenance Hemodialysis (Total N = 59)

Period	Number of Events	Observed Person-Days	Incident Rate, 1000 Person-Days (95% CI)	IRR (95% CI)
Periods not at risk	32	14,534	2.20 (1.56–3.11)	Reference
Baseline (−30 to −1 days)	2	1770	1.13 (0.28–4.52)	0.513 (0.123–2.141)
Risk period (0 to 5 days)	1	354	2.82 (0.40–20.05)	1.283 (0.175–9.389)
Risk period (6 to 30 days)	3	1416	2.12 (0.68–6.57)	0.962 (0.295–3.142)
Risk period (31 to 60 days)	11	1770	6.21 (3.44–11.22)	2.823 (1.423–5.600)
Risk period (61 to 120 days)	10	3520	2.84 (1.53–5.28)	1.290 (0.634–2.625)

Abbreviations: ESRD, end-stage renal disease; IRR, incident rate ratio.

Table 3 Incident Rate and IRR of Bone Fracture Events in Each Risk Period, Compared to Periods Not at Risk for ESRD Patients Receiving Chronic Maintenance Hemodialysis (Total N = 83)

Period	Number of Events	Observed Person-Days	Incident Rate, 1000 Person-Days (95% CI)	IRR (95% CI)
Periods not at risk	25	8118	3.08 (2.08–4.56)	Reference
Baseline (−30 to −1 days)	1	990	1.01 (0.14–7.17)	0.328 (0.044–2.421)
Risk period (0 to 5 days)	0	198	n/a	n/a
Risk period (6 to 30 days)	2	792	2.53 (0.63–10.10)	0.820 (0.194–3.462)
Risk period (31 to 60 days)	2	990	2.02 (0.51–8.08)	0.656 (0.155–2.770)
Risk period (61 to 120 days)	3	1980	1.52 (0.49–4.70)	0.492 (0.149–1.630)

Abbreviations: ESRD, end-stage renal disease; IRR, incident rate ratio; n/a, not applicable.

Table 4 Incident Rate and IRR of Thrombosis Events in Each Risk Period, Compared to Periods Not at Risk for the Non-Dialysis Population (Total N = 41)

Period	Number of Events	Observed Person-Days	Incident Rate, 1000 Person-Days (95% CI)	IRR (95% CI)
Periods not at risk	26	10,099	2.57 (1.75–3.78)	Reference
Baseline (−30 to −1 days)	2	1230	1.63 (0.41–0.65)	0.632 (0.150–2.661)
Risk period (0 to 5 days)	1	246	4.07 (0.57–28.86)	1.579 (0.214–11.640)
Risk period (6 to 30 days)	2	984	2.03 (0.51–8.13)	0.789 (0.187–3.326)
Risk period (31 to 60 days)	3	1230	2.44 (0.79–7.56)	0.947 (0.287–3.130)
Risk period (61 to 120 days)	7	2447	2.86 (1.36–6.00)	1.111 (0.482–2.560)

Abbreviation: IRR, incident rate ratio.