Medicine use and vitamin status in elderly Europeans

The relationship between medicine use and plasma levels of beta-carotene, retinol, alpha-tocopherol, cobalamin, folate and pyridoxal-5'-phosphate was investigated in 676 men and 759 women, aged 74 to 79 years, from 13 towns in 11 European countries. Information on medicine use was obtained by questionnaire. Vitamin concentrations were determined in fasting blood samples. The percentage of subjects using drugs was 83%. Antihypertensive drugs, analgesics, diuretics, sleeping tablets and psychotropics were most frequently used. Plasma retinol concentration, plasma beta-carotene concentration in smokers and plasma alpha-tocopherol concentration in ex-smokers were significantly different between subjects using drugs and those taking no medication. As expected the plasma level of beta-carotene was lower in medicine users (relative adjusted difference: -0.26 micromol/l, 95% CI[-0.45;0.01]). However, plasma levels of retinol and alpha-tocopherol were higher (absolute adjusted difference: 0.07 micromol/l, 95% CI[0.00;0.14] and 2.29 micromol/l, 95% CI[0.56;4.02] respectively). Folate and cobalamin were only significantly different with use of specific drug groups. The results of this study suggest that in rather healthy elderly people medicine use affects plasma levels of beta-carotene and cobalamin in a negative way, and has a positive effect on plasma levels of retinol, alpha-tocopherol and folate.