Table 4.

RRs for quartiles of plasma concentrations of B vitamins and metabolites

AnalyteCases/controlsRR*
P
2nd quartile3rd quartile4th quartile (high)
Betaine522/9591.16 (0.84-1.61)1.31 (0.94-1.81)1.36 (0.98-1.88)0.08
Choline522/9590.91 (0.65-1.28)1.05 (0.74-1.47)1.48 (1.07-2.04)0.03
Cysteine551/10350.84 (0.63-1.13)0.91 (0.68-1.23)0.73 (0.53-1.00)0.20
MMA548/10250.68 (0.50-0.92)0.88 (0.66-1.18)0.81 (0.60-1.09)0.03
Methionine551/10350.98 (0.73-1.31)1.15 (0.85-1.55)0.94 (0.69-1.29)0.63
Vitamin B2543/10141.06 (0.78-1.43)1.03 (0.76-1.40)1.36 (1.02-1.83)0.04
Vitamin B6543/10140.99 (0.74-1.33)1.07 (0.80-1.43)0.91 (0.67-1.23)0.94
  • * Unadjusted RRs relative the 1st quintile. Adjusting for potential confounders had essentially no effect on the RR estimates (data not shown).

  • Odds ratios were calculated as estimates of RRs with the use of conditional logistic regression.

  • P values were calculated by replacing the categorical quartile variables with the base 2 logarithm of the observed concentration in the logistic regression model.