. Author manuscript; available in PMC: 2019 May 1.

Published in final edited form as: Br J Haematol. 2018 Apr 20;181(4):505–514. doi: 10.1111/bjh.15229

Table III.

Association of putative risk factors with BL risk in participants aged 20–59 years and 60+ years.

	20–59 years						60+ years
	Case (N=69)	Control (N=268)	OR (95% CI)	P	aOR (95% CI)^*	P	Case (N=60)	Control (N=232)	OR (95%CI)	P	aOR (95% CI)^**	P
BMI^†
T1	14	40	Ref.				17	55	Ref.
T2	12	42	0.80 (0.32 – 2.04)	0.65			12	58	0.64 (0.27 – 1.53)	0.31
T3	14	40	1.07 (0.44 – 2.56)	0.89			13	55	0.80 (0.35 – 1.84)	0.60
Missing	29	146	N/A				18	64	N/A
Trend				0.63						0.73

Smoking
Never	32	54	Ref.		Ref.		15	41	Ref.		Ref.
Former	22	111	0.25 (0.12 – 0.50)	0.001	0.22 (0.09 – 0.52)	<0.001	41	134	0.76 (0.36 – 1.58)	0.61	0.61 (0.27 – 1.34)	0.22
Current	11	74	0.20 (0.09 – 0.46)	<0.001	0.12 (0.04 – 0.35)	<0.001	3	45	0.18 (0.05 – 0.67)	0.01	0.14 (0.03 – 0.58)	0.007
Missing	4	29	N/A		N/A	N/A	1	12	N/A		N/A
P_trend				<.0001		<0.001				0.013		0.007

Any Infection
Never	13	76	Ref.				7	27	Ref.
Ever	56	192	1.76 (0.87 – 3.54)	0.12			53	205	0.95 (0.37 – 2.47)	0.92

Hepatitis
Never	56	232	Ref.				54	223	Ref.		Ref.
Ever	13	36	1.59 (0.77 – 3.31)	0.21			6	9	3.41 (1.01 – 11.5)	0.05	3.21 (0.89 – 11.6)	0.08

EBV
Never	62	263	Ref.		Ref.		58	230	Ref.		Ref.
Ever^*	7	5	5.60 (1.78 – 17.6)	0.003	5.69 (1.29 – 25.1)	0.021	2	2	4.00 (0.56 – 28.4)	0.17	11.8 (0.96 – 144.2)	0.05

HIV/AIDS
Never	53	264	Ref.		Ref.		57	232
Ever^*	16	4	20.6 (5.98 – 70.7)	<0.001	40.4 (7.74 – 211.1)	<0.0001	3	0

Malaria
Never	65	266	Ref.		Ref.		59	225	Ref.
Ever	4	2	8.00 (1.46 – 43.7)	0.016	44.0 (2.63 – 735.3)	0.008	NS	NS	0.57 (0.07 – 4.64)	0.60

Use of Prednisone
Never	67	262	Ref.				53	225	Ref.		Ref.
Ever	2	6	1.33 (0.27 – 6.60)	0.73			7	7	7.30 (1.81 – 29.4)	0.009	7.78 (1.85 – 32.5)	0.005

The estimates are from multivariable models including smoking, EBV, HIV/AIDS, malaria controlling for one another, and adjusted for years of observation in the CPRD.

^**

The estimates are from multivariable models including smoking, hepatitis, EBV, use of prednisone controlling for one another, and adjusted for years of observation in the CPRD.

^†

BMI tertile values for adults aged 20–59 years are: T1 (<24.63), T2 (>=24.63 to 28.88) and T3 (>28.88); the corresponding values for adults aged 60++ years are T1 (<25.57), T2 (>=25.57 to 28.74) and T3 (>=28.74)

Abbreviations: 95% CI: 95% Confidence Interval; AIDS: acquired immune deficiency syndrome; BL: Burkitt lymphoma; BMI: body mass index; CPRD: Clinical Practice Research Datalink; EBV: Epstein–Barr virus; HIV: human immunodeficiency virus; N/A; not applicable due to missing data; NS; cell numbers suppressed because one cell has one subject; OR: Odds ratio; P: P value for heterogeneity; P_trend: P value for trend across categories; Ref.: Reference category