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A R Ness

Publications and source records attributed to A R Ness.

At least 19 recordsLinked to original sources
PubMed2001

Milk, coronary heart disease and mortality.

STUDY OBJECTIVE: To study the association between reported milk consumption and cardiovascular and all cause mortality. DESIGN: A prospective study of 5765 men aged 35-64 at the time of examination. SETTING: Workplaces in the west of Scotland between 1970 and 1973. PARTICIPANTS: Men who completed a health and lifestyle questionnaire, which asked about daily milk consumption, and who attended for a medical examination. MAIN RESULTS: 150 (2.6%) men reported drinking more than one and a third pints a day, Some 2977 (51.6%) reported drinking between a third and one and a third pints a day and 2638 (45.8%) reported drinking less than a third of a pint a day. There were a total of 2350 deaths over the 25 year follow up period, of which 892 deaths were attributed to coronary heart disease. The relative risk, adjusted for socioeconomic position, health behaviours and health status for deaths from all causes for men who drank one third to one and a third pints a day versus those who drank less than a third of a pint was 0.90 (95% CI 0.83, 0.97). The adjusted relative risk for deaths attributed to coronary heart disease for men who drank one third to one and a third pints a day versus those who drank less than one third of a pint was 0.92 (95% CI 0.81, 1.06). CONCLUSIONS: No evidence was found that men who consumed milk each day, at a time when most milk consumed was full fat milk, were at increased risk of death from all causes or death from coronary heart disease.

Adult↗
PubMed2000

The effects of dietary supplementation on growth and adult mortality: a re-analysis and follow-up of a pre-war study.

The aim of this study was to re-analyse a diet supplementation study conducted in the 1930s and investigate the effects of food supplementation on children's growth and later adult mortality. A non-randomised controlled trial was carried out in eight of the sixteen centres participating in the Carnegie Survey of Diet and Health in pre-war Britain (1937-39). Food supplements were given for 12 months either at school or as food parcels sent to the family home. 545 children aged 2-14 received food supplements and 494 children of a similar age acted as their controls. The children came from 465 families. The increase in childhood height and its components-leg length and trunk length-over 12 months follow-up were measured. Mortality from all causes over 60 years follow-up to 1998 was also assessed. There were important differences between fed and control children at baseline. Supplemented children came from larger families with poorer diets and most were examined, on average, 12 days later than control children. After adjustment for baseline imbalances those receiving supplements increased in height by 3.7 mm (95% CI 1.9-5.5) more than the controls. After adjustment, most of the difference in growth appeared to arise as a result of increases in leg length. After adjustment for confounding factors measured in childhood, no significant effect of childhood food supplements on adult mortality was seen. The age-adjusted hazard ratio for all cause mortality was higher in the supplemented compared to control subjects: 1.13 95% CI (0.77-1.64). We found that provision of childhood food supplements led to increased growth amongst supplemented children. The increases in height in this study were mainly as a result of increases in leg length and are similar to those found in a more recent randomised trial in South Wales. Whilst other analyses suggest that childhood height is important in predicting adult mortality patterns, we found no significant effect of childhood food supplements on adult mortality patterns in this study, although the study lacked statistical power to detect small but, nevertheless, important differences in mortality. Larger randomised trials with long term follow-up would be required to investigate the impact of childhood food supplementation on adult health.

Adolescent↗
PubMed1999

Plasma vitamin C: what does it measure?

OBJECTIVE: To examine the association between self-reported consumption of foods and plasma vitamin C levels. DESIGN: A cross-sectional analysis of dietary data and plasma vitamin C levels. Subjects placed the following foods into frequency categories: fresh fruit, leafy greens, other vegetables, fatty fish, other fish, chicken, meat, meat products, eggs, cheese and brown bread. The six frequency categories ranged from 'never' to 'at least daily'. Plasma vitamin C was measured by fluorometric assay. SETTING: A population-based cohort study in Norfolk, UK. SUBJECTS: 598 men and 566 women aged 45-74 years not taking vitamin supplements. RESULTS: Plasma vitamin C was positively correlated with intake of fresh fruit (r=0.29 in men and r=0.25 in women, P<0.001), leafy greens (r=0.20 in men P<0.001, r=0.13 in women P<0.01), other vegetables (r=0.20 in men P<0.001, r=0.14 in women P<0.01) and brown bread (r=0.28 in men, r=0.17 in women, P<0.001) and negatively associated with intake of meat products (r=-0.13 in men P=0.02, r=-0.10 in women P<0.01). The difference in plasma vitamin C between never and daily eaters of brown bread was 13.6 micronol l(-1) in men and 9.9 micromol l(-1) in women, P<0.001. CONCLUSIONS: These data suggest that plasma vitamin C is not only a marker of foods rich in vitamin C but of certain patterns of food consumption. Such patterns are likely to be population specific and might explain inconsistencies in biomarker-disease associations.

Aged↗
PubMed1999

The long-term effect of advice to eat more fish on blood pressure in men with coronary disease: results from the diet and reinfarction trial.

BACKGROUND: Systematic reviews of fish and fish oil supplements have reported modest reductions in blood pressure (BP). Many of the trials included in these reviews used high doses of fish oil and most were of short duration. METHOD: Between 1983 and 1987 2033 men under the age of 70, who had recently suffered a myocardial infarction, were enrolled in a 2-year trial of dietary advice-the Diet and Reinfarction Trial (DART). Participants were randomised in a factorial design to receive intensive advice to eat more fish, less fat or more fibre. Those men randomised to receive fish advice were encouraged to eat two portions of fatty fish each week. Intake of eicosapentaenoic acid was 0.33 g per day in the fish advice arm and 0.10 g per day in men not given fish advice. RESULTS: The difference in systolic BP in the fish advice arm, adjusted for age and BP at baseline, was -0.61 mm Hg (95% CI -2.15, 0.92) at 6 months and 0.40 mm Hg (95% CI -1.33, 2.13) at 2 years. The difference in diastolic BP in the fish advice arm, adjusted for age and BP at baseline, was -0.50 mm Hg (95% CI -1.47, 0.46) at 6 months and 0.19 mm Hg (95% CI -0.88, 1.26) at 2 years. CONCLUSIONS: Advice to eat modest amounts of fish has little effect on BP in men with coronary disease.

Aged↗
PubMed1999

Plasma vitamin C levels in men and women from different ethnic backgrounds living in England.

BACKGROUND: People of South Asian origin living in the UK have higher death rates due to coronary heart disease than whites. The reasons for these differences are not fully understood. Previous attempts to relate diet to cardiovascular risk in South Asians have been inconclusive. METHODS: We compared the levels of plasma vitamin C in a cross-sectional population-based study of 1018 men and women aged 40-59 (455 men, 563 women, 328 South Asians, 355 of African descent, 335 whites) co-resident in a geographically defined area of South London, when allowing for potential confounders. RESULTS: Fasting plasma vitamin C levels were significantly higher in women, vegetarians, supplement takers and non-smokers. After adjustment for age, body mass index, current smoking, supplement use and vegetarianism the mean plasma vitamin C levels were 38.8 (SE 1.6) mumol/l in white men, 36.5 (1.6) mumol/l in men of African descent and 32.9 (1.5) mumol/l in South Asian men (P = 0.033 by analysis of co-variance). In women the adjusted mean plasma vitamin C levels were 52.4 (1.6) mumol/l in whites, 46.0 (1.4) mumol/l in women of African descent and 37.3 (1.8) mumol/l in South Asians (P < 0.0001 by analysis of covariance). South Asians had lower levels than whites in both men (difference 6.4 [95% CI: 1.5, 11.3] mumol/l) and women (16.8 [95% CI: 11.5, 22.1] mumol/l). South Asian women, but not men, also had lower levels than those of African descent (8.8 [95% CI: 4.5, 13.1] mumol/l). African women, but not men, had lower levels than white women (6.6 [95% CI: 2.3, 10.9] mumol/l). No significant differences were seen between Caribbeans and West Africans or between South Asian Hindus and Muslims. CONCLUSIONS: These data suggest that important dietary differences in vitamin C exist between different ethnic groups living in England. The larger differences in South Asians may contribute to their increased coronary risk.

Adult↗
PubMed1997

Vitamin C and blood pressure--an overview.

BACKGROUND: Laboratory and some epidemiological studies suggest that antioxidants, such as vitamin C, are protective for cardiovascular disease. This protective effect may be mediated through blood pressure (BP). This is the first systematic review of epidemiological studies of vitamin C and BP. METHOD: Published cross-sectional studies, prospective studies and trials in humans were identified that examined the association between vitamin C intake or plasma vitamin C levels and BP. Relevant references were located by MEDLINE search 1966-1996, EMBASE search 1980-1996, by searching personal bibliographies, books and reviews and from citations in located articles. RESULTS: Cross-sectional data were available from 18 populations. Ten of 14 reported an inverse association between plasma vitamin C and BP and three of four reported an inverse association with vitamin C intake. The two non-randomised and four randomised controlled trials were all small. Of the randomised trials one reported a significant decrease in BP, one a non-significant decrease and two were uninterpretable. CONCLUSIONS: We found a consistent cross-sectional association between higher vitamin C intake or status and lower BP, though no study controlled adequately for confounding by other dietary factors. Further cross-sectional studies are required to establish whether an independent association exists. If this is shown to be the case larger and longer term trials will be needed to confirm the association is causal. Potentially the impact on cardiovascular disease of a modest change in mean population vitamin C intake is large.

Ascorbic Acid↗
PubMed1997

Fruit and vegetables, and cardiovascular disease: a review.

BACKGROUND: Increased interest in the potential cardio-protective effects of fruit and vegetables is currently unsupported by systematic reviews of the reported associations of these foods with risk. METHOD: All ecological, case-control, cohort studies and unconfounded trials in humans were eligible for inclusion. Eligible outcomes were symptomatic coronary heart disease, stroke and total circulatory disease. Only studies of diet that reported on fresh fruit and vegetables or a nutrient which could serve as a proxy (reversing the usual direction of inference) were included. MEDLINE (1966-1995) and EMBASE (1980-1995) were searched using the terms cerebrovascular disorder, coronary heart disease, fruit(s) and vegetable(s) as keywords. Personal bibliographies, books and reviews were also searched, as were citations in located reports. RESULTS: For coronary heart disease nine of ten ecological studies, two of three case-control studies and six of 16 cohort studies found a significant protective association with consumption of fruit and vegetables or surrogate nutrients. For stroke three of five ecological studies, none (of one) case-control study and six of eight cohort studies found a significant protective association with consumption of fruit and vegetables or surrogate nutrients. For total circulatory disease, one of two cohort studies reported a significant protective association. No attempt was made to arrive at a summary measure of the association because of the differences in study type, study quality and the different exposure measures used. CONCLUSIONS: Although null findings may be underreported the results are consistent with a strong protective effect of fruit and vegetables for stroke and a weaker protective effect on coronary heart disease. Greater use of food-based hypotheses and analyses, would complement existing nutrient-based analyses and help guide the search for underlying causes.

Cardiovascular Diseases↗
PubMed1996

Vitamin c status and undiagnosed angina.

BACKGROUND: Vitamin C has been suggested to be protective for coronary heart disease but the evidence from epidemiological studies is inconclusive and most studies have been conducted in men. We examined the cross-sectional relationship between vitamin C status and previously undiagnosed angina in women. METHODS: Women aged 45-74 years were recruited from general practices. They completed a health and lifestyle questionnaire and attended for a health check and a blood test. Non-fasting plasma vitamin C was used to define vitamin status and a self-completed Rose angina questionnaire was used to identify cases. RESULTS: Forty-two women with previously undiagnosed angina (cases) were compared with 877 women with no reported angina (controls). The mean plasma vitamin C was 50.2 mumol/l in cases and 58.3 mumol/l in controls. The age-adjusted odds ratio for a 50 mumol/l increase in plasma vitamin C was 0.34 (95% confidence interval 0.15-0.79). The odds ratio was unaltered after adjustment for body mass index, smoking and established coronary risk factors, and after stratification by smoking, vitamin supplementation and hormone replacement. CONCLUSIONS: This cross-sectional analysis showed an association in women between lower plasma levels of vitamin C and previously undiagnosed angina. Although we are unable to exclude the possibility that symptomatic prevalent disease modifies plasma vitamin C levels, these data are consistent with a protective effect of vitamin C for coronary heart disease. This relationship requires confirmation in further prospective studies and trials of vitamin C supplementation.

Aged↗
PubMed1996

Vitamin C status and blood pressure.

OBJECTIVE: To examine the cross-sectional relationship between blood pressure and plasma vitamin C. DESIGN: A cross-sectional analysis. SETTING: A population-based study. SUBJECTS: The subjects were 835 men and 1025 women aged 45-75 years registered with general practices in Norfolk. INTERVENTIONS: Completion of health and lifestyle questionnaire and attendance for a health check. MAIN OUTCOME MEASURES: Diastolic blood pressure (DBP), systolic blood pressure (SBP) and plasma vitamin C level. RESULTS: The mean SBP was 135.8 +/- 18.5 mmHg (mean +/- SD) and the mean DBP was 82.5 +/- 11.3 mmHg. The mean plasma vitamin C level was 52.6 +/- 19.7 mumol/l. The plasma vitamin C level was negatively correlated both with SBP and with DBP. These correlations persisted after adjustment for age, sex and body mass index. Adjusting for other confounders including cigarette smoking, physical activity and alcohol intake did not alter the observed association. Exclusion of subjects taking vitamin supplements and those with known hypertension did not affect the results. The differences in SBP and in DBP for a 50 mumol/l difference in vitamin C, estimated using linear regression, were -3.6 and -2.6 mmHg, respectively. CONCLUSIONS: The plasma vitamin C level may be a marker of other factors; nevertheless, these results are consistent with other published work indicating that a high intake of vitamin C from food confers protection against raised blood pressure and strokes.

Aged↗
PubMed1996

Vitamin C status and respiratory function.

OBJECTIVE: To examine the cross sectional relationship between respiratory function and plasma vitamin C. DESIGN: Cross sectional analysis. SETTING: Population based study. SUBJECTS: 835 Men and 1025 women aged 45 to 75 registered with GP practices in Norfolk. INTERVENTIONS: Completion of health and lifestyle questionnaire and attendance for a health check. MAIN OUTCOME MEASURES: Forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and non fasting plasma vitamin C. RESULTS: Plasma vitamin C was positively correlated, after adjustment for age and height, with both FEV1 (r = 0.17, P < 0.001) and FVC (r = 0.14, p < 0.001) in men. The association in women was weaker and not statistically significant. Adjusting for other possible factors and exclusion of various groups did not alter the observed associations. The differences in FEV1 and FVC in men, adjusted for age, height and cigarette smoking, for a 50 micromol/L difference in vitamin C were 0.22 litres (95% CI 0.10-0.33) and 0.23 litres (95% CI 0.09-0.37) respectively. The population distribution was shifted such that 12.1% of men with vitamin C levels < or = 30 micromol/L had an FEV1 of less than two litres, compared with 4.6% with levels > or = 60 micromol/L. CONCLUSIONS: These findings are consistent with other studies of vitamin C and respiratory function and suggest that vitamin C may be protective for lung function through the whole normal range of dietary intake and lung function.

Aged↗
PubMed1996

Vitamin C status and serum lipids.

OBJECTIVES: To examine the cross sectional relationship between plasma vitamin C and serum lipids. DESIGN: Cross-sectional analysis. SETTING: Population based study. SUBJECTS: 835 Men and 1025 women aged 45-75 registered with GP practices in Norfolk. INTERVENTIONS: Completion of health and lifestyle questionnaire and attendance for a health check. MAIN OUTCOME MEASURES: Non fasting plasma vitamin C and serum lipids. RESULTS: Plasma vitamin C was not correlated with serum total cholesterol or LDL cholesterol in men or women. In women plasma vitamin C was positively correlated with HDL cholesterol r = 0.15 (P < 0.001) and negatively correlated with triglyceride r = -0.17 P < 0.001). These correlations persisted after adjustment for age and body mass index. The association in men was weaker and after adjustment for age and body mass index was no longer statistically significant. Exclusion of subjects taking vitamin supplements and those with known hyperlipidaemic did not affect the findings. The difference in HDL cholesterol, adjusted for age, body mass index and alcohol intake, for a 50 micromol/l difference in vitamin C, estimated using linear regression, was 0.11 mmol/l in women. The difference in triglyceride, adjusted for age and body mass index was -0.16 mmol/l in women. CONCLUSIONS: Plasma vitamin C level may be a marker of other factors; nevertheless these results are consistent with other published work indicating that a high intake of vitamin C from food raises serum HDL cholesterol and lowers serum triglyceride.

Aged↗
PubMed1996

Vitamin C and cardiovascular disease: a systematic review.

BACKGROUND: Laboratory studies suggest that antioxidants, such as Vitamin C, are important inhibitors of atherosclerotic lesions. Most epidemiological reviews have considered all antioxidants together. This review seeks to clarify the current state of knowledge specifically concerned with vitamin C. METHODS: All ecological studies, case-control studies, prospective studies and trials in humans that examined the association between vitamin C intake or blood levels of vitamin C and cardiovascular disease were included. Relevant references were located by MEDLINE search for articles published from 1966 to 1996, by an EMBASE search for articles published from 1980 to 1996, by searching personal bibliographies, books and reviews and from citations in located articles. RESULTS: For coronary heart disease four of seven ecological studies, one of four case-control studies and three of 12 cohort studies found a significant protective association with vitamin C intake or status. For strokes two of two ecological studies, none of one case-control study and two of seven cohort studies found a significant protective association. For total circulatory disease, two of three cohort studies reported a significant protective association. CONCLUSIONS: The evidence, albeit limited, is consistent with vitamin C having protective effect against stroke whereas the evidence that vitamin C is protective against coronary heart disease is less consistent. The lack of an association for coronary heart disease could be explained in terms of there being a true lack of effect, dietary measurement error, a threshold effect, and effect of seasonal variations in intake, an interaction with other dietary constituents or a relatively short duration of follow-up.

Ascorbic Acid↗