Do dietary patterns in older men influence change in homocysteine through folate fortification? The Normative Aging Study.

OBJECTIVE: We aimed to describe the difference in B-vitamin intake and in plasma B-vitamin and homocysteine concentrations before and after folic acid fortification, in relation to dietary patterns. DESIGN: The Normative Aging Study (NAS) is a longitudinal study on ageing. Between 1961 and 1970, 2280 male volunteers aged 21-80 years (mean 42 years) were recruited. Dietary intake data have been collected since 1987 and assessment of plasma B vitamins and homocysteine was added in 1993. SETTING: Boston, Massachusetts, USA. SUBJECTS: In the present study, 354 men who had completed at least one FFQ and one measurement of homocysteine, both before and after the fortification period, were included. RESULTS: Three dietary patterns were identified by cluster analysis: (i) a prudent pattern, with relatively high intakes of fruit, vegetables, low-fat milk and breakfast cereals; (ii) an unhealthy pattern, with high intakes of baked products, sweets and added fats; and (iii) a low fruit and vegetable but relatively high alcohol intake pattern. Dietary intake and plasma concentrations of folate increased significantly (P < 0.05) among all dietary patterns after the fortification period. Homocysteine tended to decrease in supplement non-users and in subjects in the high alcohol, low fruit and vegetable dietary pattern (both P = 0.08). CONCLUSIONS: After fortification with folic acid, folate intake and plasma folate concentration increased significantly in all dietary patterns. There was a trend towards greatest homocysteine lowering in the high alcohol, low fruit and vegetable group.

Supplement use and mortality: the SENECA study.

BACKGROUND: It is hypothesis that in relatively healthy older people supplement usage can be consider as healthy life style habit and as such can positively influence longevity. AIM OF THE STUDY: To determine whether supplement use was associated with all-cause mortality in the participants of the SENECA study. METHODS: Baseline measurements were carried out in 1988/1989 among 75 to 80-year-old people living in 15 European small towns. All-cause mortality was followed up to April 30, 1999. Data from 920 men and 980 women who were ischemic heart diseases-, stroke- and cancer-free at baseline were included. The multivariate adjusted (for sex, age, years of education, physical activity, BMI, chronic diseases, Mediterranean Diet Score, alcohol use and the place of living) hazard ratio (HRs) and 95% confidence intervals (CIs) of mortality by use of any type of nutrient supplement and by particular nutrient supplement use were estimated by Cox proportional hazards regression models. RESULTS: At baseline, 13% of participants used nutritional supplements, 19% of subjects were smokers. During 10 years of follow-up 445 men and 252 women died. Among non-smokers no significant associations between total supplement use and particular nutrient supplement use were observed. Among smokers use of any type of supplements (Multivariate HR: 1.52; 95%CI: 1.02-2.28), use of vitamin B(1) (Multivariate HR: 1.57; 95%CI: 1.00-2.48) and vitamin B(2) supplements (Multivariate HR: 1.60; 95%CI: 1.00-2.56) were associated with a significantly higher risk of all-cause mortality. The similar tendencies were observed among vitamin B(6) and vitamin C supplement users who were smokers. CONCLUSIONS: Among smokers, participants of the SENECA study, supplement use increased all-cause mortality risk.

Assessment of susceptibility of Plasmodium falciparum to chloroquine, quinine, mefloquine, sulfadoxine-pyrimethamine and artemisinin in southern Viet Nam.

Resistance to antimalarial chemotherapy is a major concern for malaria control in Viet Nam. In this study undertaken in 1998, 65 patients with uncomplicated Plasmodium falciparum malaria were monitored for 28 days after completion of a 5-day treatment course with artemisinin. Overall 36.9% (24/65) of patients had recurrent parasitaemia during the surveillance period. P. falciparum isolates were tested for sensitivity in vitro to chloroquine, mefloquine, quinine, sulfadoxine-pyrimethamine and results were compared to those from a similar study in 1995. Increased parasite sensitivity to sulfadoxine-pyrimethamine, chloroquine and quinine was demonstrated, with significantly lower mean EC50 and EC99 values in 1998 compared to 1995. Parasite sensitivity to mefloquine did not differ significantly in the 2 surveys. Isolates were also tested for sensitivity in vitro to artemisinin in the 1998 survey. The mean EC50 was 0.03 mumol/L and the EC99 was 0.94 mumol/L. Parasite sensitivity to artemisinin will need to be monitored in view of its increasing use in Viet Nam.

Resistance of Plasmodium falciparum to antimalarial drugs in a highly endemic area of southern Viet Nam: a study in vivo and in vitro.

To assess the antimalarial sensitivity of Plasmodium falciparum in vivo and in vitro in a highly endemic area of southern Viet Nam, a field study was conducted (in 1999) at a rubber plantation in Binh Phuoc Province north of Ho Chi Minh City. Fifty patients were treated with either artesunate (4 mg/kg on day 0, then 2 mg/kg on day 1 to 4) or mefloquine (10 mg/kg at 0 h, then 5 mg/kg at 6 h), and their progress was followed for 28 days under standard WHO protocols. Blood spots were taken at baseline from all patients, as well as from those who redeveloped parasitaemia during follow-up, for polymerase chain reaction (PCR) determination of parasite genotypes to assist differentiation of re-infection from recrudescence. Both treatments cleared parasites within 5 days. Of the 25 mefloquine-treated patients, 2 (8%) re-presented with probable re-infections. For artesunate, 4 patients (16%) had re-infections and 5 (20%) had recrudescences. Sensitivity tests in vitro of pre-treatment P. falciparum isolates showed geometric mean IC50 values of 29, 38, 209 and 15 nmol/L for chloroquine (n = 32), mefloquine (n = 33), quinine (n = 31) and artemisinin (n = 31), respectively. There were significant correlations between IC50s for artemisinin and mefloquine (r = 0.72, P = 0.004), and chloroquine and quinine (r = 0.44, P = 0.05). These data show that, although mefloquine has been used for 10 years in Binh Phuoc Province, it remains fully effective, perhaps because an artemisinin derivative is commonly given at the same time. The recrudescence rate for artesunate is similar to those reported in other epidemiological contexts. The present in-vitro data imply that quinine remains effective and that reduced drug pressure has been associated with increased sensitivity of local strains of P. falciparum to chloroquine. Although from one hyperendemic area, these results may have implications for antimalarial prophylaxis and treatment strategies for residents and travellers to southern Viet Nam.