Table 1

Characteristics of the study population

VariableControlsCasesp Value*
Data are mean (95% confidence interval) or per cent.
*Adjusted for age and sex.
†Geometric mean.
CAMCOG, [spell out]; holoTC, holotranscobalamin; MMA, methylmalonic acid; MMSE, mini-mental state examination; tHcy, total homocysteine.
Age (years)70.5 (68.4 to 72.7)75.2 (72.8 to 77.7)0.005
Female (%)67.856.70.232
Smokers (%)14.516.70.758
MMSE score28.9 (27.5 to 30.3)11.4 (9.8 to 13.0)<0.001
CAMCOG score100.4 (95.6 to 105.2)39.3 (33.9 to 44.8)<0.001
ApoE ε4 polymorphism (%)19.573.2<0.001
Serum cobalamin (pmol/l)†302 (269 to 340)261 (228 to 298)0.107
Serum holoTC (pmol/l)†57.1 (51.1 to 64.1)41.1 (36.1 to 46.8)<0.001
Serum MMA (μmol/l)†0.23 (0.20 to 0.26)0.28 (0.25 to 0.32)0.027
Serum tHcy (μmol/l)†12.2 (11.4 to 13.1)15.0 (13.9 to 16.3)<0.001
Serum folate (nmol/l)†21.5 (18.9 to 24.5)15.2 (13.1 to 17.6)0.001
Creatinine (μmol/l)†94 (90 to 98)90 (85 to 94)0.196
Low cobalamin (<200 pmol/l) (%)19.030.70.158
Low holoTC (<40 pmol/l) (%)21.547.10.004
Raised MMA (≥0.30 μmol/l) (%)20.343.10.012
Raised tHcy (>14 μmol/l) (%)20.951.8<0.001
Low folate (<15 nmol/l) (%)20.554.2<0.001
Raised creatinine (>115 μmol/l) (%)17.03.80.027