To characterize relationships among blood pressure, pulse rate, vitamin C status and other protective and risk factors for older British people, from a national survey.
A cross-sectional analysis of survey data.
A population study, representative of mainland Britain.
Among 914 people of both sexes living in the community, 373 were taking blood-pressure-lowering drugs and were therefore excluded from the analyses.
Completion of an interview on health, lifestyle and dietary habits, recording of a 4-day dietary record, anthropometry and taking of a blood sample to determine haematological and biochemical status.
Systolic and diastolic blood pressures, pulse rate, indices of micronutrient status including plasma ascorbate concentration, nutrient intake and haematology.
Plasma ascorbate concentration was inversely correlated to systolic and diastolic blood pressures and pulse rate. Other covariates of blood pressure included age, sex, domicile, plasma retinol, fibrinogen and γ-tocopherol concentrations, erythrocyte count, prothrombin time and urine sodium: creatinine ratio. Covariates of pulse rate included sex, domicile, plasma fibrinogen and platelet count. Blood pressure was also correlated to intake of vitamin C.
Plasma ascorbate concentration and intake of vitamin C are covariates of blood pressure in older people living in Britain. New intervention studies are now needed, to test for possible causalities.
1Medical Research Council Dunn Nutrition Unit, Milton Road, Cambridge, UK
2Social and Community Planning Research, London, UK
3Correspondence and requests for reprints to Dr C.J. Bates, MRC Dunn Nutrition Unit, Milton Road, Cambridge CB4 1XJ, UK.
Sponsorship: The National Diet and Nutrition Survey of People Aged 65 Years or Over was funded jointly by the Ministry of Agriculture, Fisheries and Food and the Department of Health. It was conducted by Social and Community Planning Research in conjunction with the Medical Research Council's Dunn Nutrition Unit. The authors acknowledge financial support for this further analysis of the survey data from the Department of Health and the Ministry of Agriculture, Fisheries and Food.
Received 22 December 1997 Revised 2 February 1998 Accepted 20 February 1998