Table 1.

Characteristics of the case-control studies included in meta-analysis.

First author	Year	Ethnicity	Age	Sex	Case (n)	Control (n)	BCHE K allele frequency (%)		APOE ɛ4 allele frequency (%)
							Case	Control	Case	Control
Lehmann	1997	Caucasian	>65	Mixed	74	104	13	9	41	16
Brindle	1998	Caucasian	75.4	Mixed	138	165	20.3	18.8	31.4	14
Crawford	1998	Caucasian	76.4	Mixed	391	201	17.2	14.4	75	67.4
Hiltunen	1998	Caucasian	73	Mixed	59	59	12	22	100	100
Kehoe	1998	Caucasian	NA	Mixed	181	262	21	22	56.5	28.1
Singleton	1998	Caucasian	78.3	Mixed	119	83	20	17	65.5	21.4
Yamada	1998	Asian	85.1	Mixed	48	107	31.7	31.2	NA	NA
Grubber	1999	Caucasian	NA	Mixed	169	193	18.8	23	18	25.4
Ki	1999	Asian	73	Mixed	78	74	23	16	28	7
Tilley	1999	Caucasian	81	Mixed	177	118	20	19	31	11
Wiebusch	1999	Caucasian	78	Mixed	135	70	25	16	43	18
Yamamoto	1999	Asian	68.2	Mixed	149	200	15.9	15.7	NA	NA
Lee	2000	Asian	69.1	Mixed	89	101	13.5	12.3	24.2	6.9
Mattila	2000	Caucasian	>65	Mixed	80	67	21	15	13	11
McIlroy	2000	Caucasian	77.7	Mixed	175	187	26.8	14.4	34.5	31.6
Kim	2001	Asian	71.7	Mixed	164	293	11.7	10.1	NA	NA
Prince	2001	Caucasian	NA	Mixed	204	186	20.9	20.1	NA	NA
Raygani	2004	Caucasian	75	Mixed	105	129	24.2	12	25.9	6.2
Combarros	2005	Caucasian	75	Mixed	187	172	10	15	12	8
Cook	2005	Caucasian	NA	Mixed	212	316	27	20	NA	NA
Deniz-Naranjo	2007	Caucasian	>60	Mixed	282	312	19.5	19.4	48.9	22.1
Piccardi	2007	Caucasian	76.8	Mixed	158	118	21	19	18.9	5.5
Mateo	2008	Caucasian	71.3	Mixed	231	221	12	10	NA	NA
Bizzarro	2010	Caucasian	73.3	Mixed	167	129	10.1	10.2	NA	NA
Simão-Silva	2013	Caucasian	74.5	Mixed	78	80	23	21	NA	NA

NA – not available.