Association of cholesterol with risk of pancreatic cancer: A meta-analysis

Table 1 Characteristics of studies for dietary cholesterol included in the meta-analysis

Ref.	Country (year)	Study design	Mean age (case/control)Percentage of males (case/control)	Sample size (cases)	Cut-points for cholesterol exposure RR (95%CI)	Adjustment for covariates
Lin et al[13]	Japan	Case-control	64.7/65.1	327	Dietary cholesterol exposure (mg), < 206 (referent), 206-330,	Age and pack-years of smoking
	-2005		NA	-109	> 330 [2.06 (1.11-3.85)]
Chan et al[14]	United States	Case-control	NA	2233	Dietary cholesterol exposure (g/d) median, 122.8 (referent), 192.6, 257.6, 368.9 [1.5 (1.1-2.0)]	Age, sex, BMI, race, education, smoking, history of diabetes and energy intake
	-2007		54.7/51.9	-532
Hu J et al[15]	Canada	Case-control	61.6/57.1	5667	Dietary cholesterol cut-point	Age, sex, BMI, province, education, alcohol drinking, pack year smoking, total of vegetable and fruit intake, saturated fat and total energy intake
	-2012		56.2/50.5	-628	(mg/wk) < 966.261 (referent), 966.262-1412.753, 1412.754-1880.265,
					> 1880.266 [1.57 (1.09-2.26)]
Howe et al[17]	Metropolitan Toronto	Case-control	64.6/64.8	754	Mean difference per day	Caloric and fibre intake, lifetime cigarette consumption
	-1990		56.6/53.5	-249	quartile 4-quartile 1 (569 mg) [0.95 (0.51-1.75)]
Bueno de Mesquita et al[18]	Netherlands	Case-control	NA	644	Dietary cholesterol	Age, sex, response status, total smoking and dietary intake of energy
	-1991		54.9/48.3	-164	[1.33 (0.72-2.45)]
Lucenteforte et al[19]	Italy	Case-control	NA	978	First quintile of cholesterol exposure (referent), second vs first,	Year of interview, education, tobacco smoking, history of diabetes and total energy intake
	-2010		53.4/53.4	-326	third vs first, fourth vs first,
					fifth vs first [1.10 (0.68-1.77)]
Baghurst et al[26]	Australia	Case-control	NA	357	First quintile of cholesterol exposure (referent), second vs first, third vs first, fourth vs first [3.19 (1.58-6.47)]	Age and pack-years of smoking
	-1991		50.0/56.1	-104
Ghadirian et al[27]	Canada	Case-control	63.9/62.1	418	First quintile of cholesterol exposure (referent), second vs first, third vs first, fourth vs first [2.24 (0.83-6.05)]	Age, sex, lifetime cigarette consumption, response status and total energy intake
	-1995		54.2/51.5	-179
Heinen et al[28]	The Netherlands	Case-cohort	NA	120852	Dietary cholesterol (mg/d), first quintile of cholesterol exposure (referent), second vs first, third vs first, fourth vs first, fifth vs first [0.78 (0.52-1.18)]	Age, sex, BMI, energy, smoking, alcohol, history of diabetes mellitus, history of hypertension, vegetables and fruits intake
	-2009		52.9/49.1	-350
Kalapothaki et al[29]	Greece	Case-control	NA	362	Dietary cholesterol (mg), an increment of about one standard deviation of the energy-adjusted residual of the corresponding nutritional variable [1.19 (0.96-1.47)]	Age, sex, hospital, past residence, years of schooling, smoking, diabetes mellitus and energy intake
	-1993		NA	-181
Michaud et al[30]	United States	Cohort	NA	88802	Median of cholesterol exposure (g/d) 212 (referent), 275, 322, 371, 466 [1.11 (0.67-1.83)]	Pack-years of smoking, BMI, history of diabetes mellitus, caloric intake, height, physical activity, menopausal status and glycemic load intake
	-2003		NA	-178
Nöthlings et al[31]	Hawaii and Los Angeles	Cohort	65/60	190545	Cholesterol density (mg/1000 kcal per day) median intake 56.8 (referent), 81.6, 100.4, 120.8, 156.8 [1.09 (0.89-1.32)]	Age, ethnicity, history of diabetes mellitus, familial history of pancreatic cancer, smoking status and energy intake
	-2005		51.2/45.3	-482
Stolzenberg-Solomon et al[32]	Finland	Cohort	58/57	27111	First quintile of cholesterol exposure (referent), second vs first,	Energy intake, age, years of smoking and energy-adjusted saturated fat intake
	-2002		NA	-163	third vs first, fourth vs first,
					fifth vs first [0.92 (0.53-1.59)]
Zatonski et al[33]	Poland	Case-control	62.2/63.2	305	First quintile of cholesterol exposure (referent), second vs first, third vs first, fourth vs first [4.31 (1.60-11.59)]	Cigarette lifetime consumption and calories
	-1991		61.8/45.6	-110

NA: Not available; BMI: Body mass index.