Table 1 Observational studies investigating the relationship between vitamin B6, B12, methionine and pancreatic cancer risk
From: Vitamin B6, vitamin B12 and methionine and risk of pancreatic cancer: a meta-analysis
Author (year) | Design | Country | cases | Sex | Source | Exposure | Dose | Adjustment factors | Quality |
|---|---|---|---|---|---|---|---|---|---|
Baghurst (1991) [24] | PCC | Australia | 104 | Both | Diet | Vitamin B6 Vitamin B12 | Q4 vs Q1 Q4 vs Q1 | Age, Sex, energy intake, smoking, alcohol intake | 7 |
Stolzenberg-Solomon (1999) [8] | Nest case-control | Finland | 126 | Male | Serum | PLP Vitamin B12 | >  39.46 nmol/L (T3) vs ≤ 26.34 nmol/L (T1) >  550 pg/ml (T3) vs ≤ 427 pg/ml (T1) | Age, month of blood draw, completion of dietary questionnaire, study center, intervention group, serum folate | 7 |
Stolzenberg-Solomon (2001) [25] | Cohort | Finland | 157 | Male | Diet | Vitamin B6 Vitamin B12 methionine | >  2.81 mg/d (Q5) vs ≤ 2.09 mg/d (Q1) >  13.68 μg/d (Q5) vs ≤ 7.57 μg/d (Q1) >  2268 mg/d (Q5) vs ≤ 1720 mg/d (Q1) | Age, intervention, folate | 7 |
Skinner (2004) [26] | Cohort | US | 326 | NHS: women, HPS: men | Diet | Methionine | Q5 vs Q1 | Age, time period, and energy,smoking, diabetes, body mass index, and height | 6 |
Schernhammer (2007) [7] | Nest case-control | US | 208 | NHS: women HPS: men | Plasma | PLP Vitamin B12 | Q4 vs Q1 Q4 vs Q1 | Age, sex, smoking, fasting status, month of blood draw, physical activity, and a history of diabetes | 7 |
Larsson (2007) [27] | Cohort | Sweden | 147 | Male | Diet | Vitamin B6 methionine | ≥ 2.56 mg/d (Q4) vs < 1.83 mg/d (Q1) ≥ 2.02 g/d (Q4) vs < 1.59 g/d (Q1) | Age, sex, energy intake, smoking, BMI, diabetes | 7 |
Gong (2009) [14] | PCC | US | 532 | Both | Diet | Vitamin B6 Vitamin B12 methionine | ≥ 5.0 mg/d (Q5) vs < 1.9 mg/d (Q1) ≥ 14.5 mg/d (Q5) vs < 4.2 mg/d (Q1) ≥ 2060 mg/d (Q5) vs < 1443 mg/d (Q1) | Age, sex, energy intake, smoking, alcohol intake, diabetes, BMI | 7 |
Guo (2009) [28] | PCC | China | 42 | Both | Plasma | PLP | High vs low | Age, sex | 7 |
Bravi (2011) [29] | HCC | Italy | 326 | Both | Diet | Vitamin B6 | Q5 vs Q1 | Age, sex, and center, and adjusted for year of interview, education, tobacco smoking, history of diabetes, body mass index, and total energy intake | 7 |
Chuang (2011) [16] | Cohort | EU | 463 | Both | Plasma | PLP Methionine | >  54.82 nmol/L vs ≤ 23.75 nmol/L > 30.24 μmol/L vs ≤ 20.67 μmol/L | Age,sex, education, smoking status, cotinine concentration in plasma, baseline alcohol drinking, BMI and self-reported diabetes status at baseline. | 8 |
Arendt (2013) [17] | Cohort | Denmark | 698 | Both | Plasma | Vitamin B12 | >  800 pmol/L vs 200–600 pmol/L | Not mentioned | 5 |
Jansen (2013) [30] | HCC | US | 384 | Both | Diet and supplement | Vitamin B6 | Q5 vs Q1 | Age, sex, energy intake, smoking, alcohol intake, BMI | 7 |
Jansen (2014) [31] | HCC | US | 384 | Both | Diet and supplement | Vitamin B12 Methionine | Q5 vs Q1 Q5 vs Q1 | Age, sex, energy intake, smoking, alcohol intake, BMI | 7 |
Huang (2016) [32] | Cohort | Singapore | 271 | Both | Diet | Vitamin B6, Vitamin B12 Methionine | 1.33 mg/d (Q4) vs 0.88 mg/d (Q1) 3.26 μg/d (Q4) vs 0.88 μg/d (Q1) 1625.25 mg/d (Q4) vs 1073.17 (Q1) | Age, sex, year of interview, dialect group, education, BM, smoking status, diabetes, alcohol drinking, and weekly vitamin use. | 9 |
Huang (2016) [32] | Nest case-control | Singapore and China | 187 | Both | Serum | PLP | >  52.4 nmol/L vs < 20.0 nmiol/L | Smoking status, alcohol intkaek, level of education, history of diabetes, BMI, and study site | 9 |
Marley (2018) [33] | PCC | US | 150 | Both | Diet | Vitamin B6, Vitamin B12 Methionine | 3.36 mg/d (Q4) vs 1.38 mg/d (Q1) 12.2 μg/d (Q4) vs 2.7 μg/d (Q1) 2.78 g/d (Q4) vs 1.10 g/d (Q1) | Age, sex, race, education, cigarette smoking, alcohol consumption, and total physical activity, energy, total fat, fiber, vegetables, and fruits | 8 |
Nakagawa (2018) [34] | Nested case-control | Japan | 170 | Both | Plasma | Methionine | 34.0 nmol/L (Q4) vs 19.6 nmiol/L (Q1) | Age, sex, PHC area, duration of the fasting period prior to blood sampling, smoking, body mass index, and past history of diabetes mellitus. | 8 |
Huang (2020) [35] | Nest case-control | Singapore and China | 187 | Both | Serum | Methionine | Q5 vs Q1 | Age,sex, level of education, body mass index, smoking status, serum cotinine concentration, number of alcoholic drinkers per week, history of diabetes, serum pyridoxal 5′-phosphate concentration and estimated glomerular filtration rate | 9 |