Cardiovascular Surveys in Areas with Different Water Supplies

Elwood, Peter Creighton; Bainton, David; Moore, Frederick; Davies, D.F.; Wakley, E. J.; Langman, M. J. S.; Sweetnam, P. M.

doi:10.1136/bmj.2.5758.362

Cited by 21 publications

(6 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Various studies linked water softness to ischemic heart disease (2), to hypertension (3), to atherosclerosis (4), and to stroke (4). However, other studies do not confirm these observations (5,6).…”

contrasting

confidence: 46%

Atherosclerosis and hypertension induction by lead and cadmium ions: an effect prevented by calcium ion.

Revis¹,

Zinsmeister²,

Bull³

1981

Proc. Natl. Acad. Sci. U.S.A.

143

View full text Add to dashboard Cite

In epidemiological studies, both positive and negative correlations have been found between cardiovascular disease and mortality and the presence of several inorganic ions in the drinking water. In an attempt to resolve this apparent disagreement, we exposed White Carneau pigeons to drinking water containing calcium (100 ppm), magnesium (30 ppm), lead (0.8 ppm), or cadmium (0.6 ppm) and used a 24-factorial design to measure the effects of these elements in atherosclerosis and hypertension. The results indicate that (i) lead and cadmium induced aortic atherosclerosis and hypertension, and (ii) calcium protects against the cardiovascular effects of cadmium. Furthermore, the effects of lead and cadmium were promoted by magnesium, and there were indications that magnesium antagonized the atherosclerotic protective effect ofcalcium. We suggest that, if these results with the pigeon can be applied to humans, the incidence of aortic atherosclerosis and hypertension should be significantly higher in areas where the drinking water contains magnesium, lead, and cadmium with a relatively low calcium concentration. Furthermore, if hard and soft water produce similar levels of lead and cadmium uptakes, the level of magnesium may be an additional factor in aortic atherosclerosis.Over the past 20 years, epidemiological and clinical evidence on the relationship between the quality of drinking water and the death rate from cardiovascular disease has been conflicting and inconclusive. Earlier studies correlated soft water with a higher cardiovascular death rate (1). Later studies showed a similar relationship but did not agree on the type of cardiovascular disease related to soft water. Various studies linked water softness to ischemic heart disease (2), to hypertension (3), to atherosclerosis (4), and to stroke (4). However, other studies do not confirm these observations (5, 6).Several specific elements in drinking water have been implicated in epidemiological studies of cardiovascular mortality.Noting that the relative concentration ofcalcium is lower in soft water than in hard water, several investigators studied the relationship between drinking-water calcium concentration and cardiovascular mortality and observed an increase in mortality when the relative concentration of calcium was lower (7). Furthermore, some studies have shown a higher incidence of cardiovascular mortality associated with consumption of soft water with relatively high concentrations of lead and cadmium (8). Again, however, other studies fail to confirm these correlations (9).The objective of the present studies was to determine the effects of calcium, magnesium, lead, and cadmium on the induction and progression of atherosclerosis and hypertension. We chose the male White Carneau pigeon (3 months ofage) for these studies because, unlike many other experimental models, it develops spontaneous atherosclerotic lesions ofboth the aorta and coronary arteries (10). METHODSMale pigeons 3 months ofage were housed indoors (in climatecontrolled, uncrowde...

show abstract

contrasting

confidence: 46%

Atherosclerosis and hypertension induction by lead and cadmium ions: an effect prevented by calcium ion.

Revis¹,

Zinsmeister²,

Bull³

1981

Proc. Natl. Acad. Sci. U.S.A.

143

View full text Add to dashboard Cite

show abstract

“…Depending on the geographic region and the presence or absence of soft water (the latter usually being associated with areas of increased prevalence of cardiovascular disease), different metals would become dissolved in the drinking water (Schroeder and Kraemer, 1974). There have been conflicting reports regarding the possibility of increased risk factors for CAHD disease in populations drinking soft water (Elwood et al, 1971;Stitt et al, 1973). If there were differences in known risk factors, such as blood pressure or plasma cholesterol, it is not clear whether these are secondary to the difference in the hardness of the drinking water or a cause of the difference in the observed CAHD mortality.…”

Section: Metals and Trace Elementsmentioning

confidence: 99%

Cardiovascular disease and environmental exposure.

Rosenman

1979

Occupational and Environmental Medicine

View full text Add to dashboard Cite

This paper reviews the possible association between cardiovascular disease and occupational and environmental agents. The effects ofcarbon monoxide, fibrogenic dusts, carbon disulphide, heavy metals, noise, radiation, heat, cold, solvents and fluorocarbons are discussed. New directions for investigation are suggested.There has been a growing awareness of the relationship between the quality of the environment and the incidence of human disease, particularly in relation to chemical carcinogenesis and lung disease. In contrast, studies of the aetiology of coronary arteriosclerotic heart disease (CAHD) have not usually been concerned with exposure to environmental toxins. Those studies which have examined cardiovascular disease in relation to occupation have largely been concerned with the effect of sedentary as opposed to active work (Morris, 1959;Karvonen et al., 1961;Pell and D'Alonzo, 1963;Paffenbarger and Hale, 1975;Baxter et al., 1976;Menotti and Puddu, 1976) or the psychological stress of the work (Jenkins, 1976 The information presented in the following discussion will explore possible environmental risk factors and, in the process, new means of intervention may be suggested. The inconclusiveness of much of the data, rather than indicating an absence of effect, underlines the need for further study.The discussion of cardiovascular disease will be mainly limited to possible environmental aetiological factors of CAHD. By inference one might assume that many of these same factors would be important in the incidence of cerebrovascular disease. Included in the discussion of CAHD will be agents that cause arrhythmias or vasospasm. Although these two physiological responses are not necessarily related to arteriosclerosis it is impossible, without good autopsy data, to separate sudden death caused by these mechanisms from sudden death secondary to myocardial infarcts of atherosclerotic origin. Agents having a direct effect on myocardial tissue will also be reviewed. Environmental causes of congenital heart disease will not be discussed.The Table lists of men in the workplace, where one finds the highest exposure to the agents in the Table, may contribute, to some extent, to the known differences in incidence of heart disease between the sexes. Carbon monoxide may be an important factor in the strong association between cigarette smoking and CAHD. Carbon disulphide-exposed workers may have more CAHD because of increased blood pressure and/or cholesterol levels. Certain heavy metals may increase the incidence of CAHD by their toxic renal effect which may subsequently cause hypertension.The monoclonal theory ofarteriosclerosis (Benditt, 1977) suggests a possible mechanism for environmental agents. Cells in aortic atherosclerotic plaques from women heterozygous for X-linked glucosephosphate dehydrogenase deficiency were examined at autopsy for their clonal origin. The cells in fibrous plaques were found to be of monoclonal origin, compared with cells in normal intima (Benditt and Benditt, 1973 (Benditt, 1977)...

show abstract

“…This association may arise because of an effect of water on a known 'risk factor' such as blood pressure, or the susceptibility of the myocardium could be affected, or some process relevant to intravascular thrombosis could be involved.In an earlier study (Elwood et al, 1971) we presented data which showed no evidence of any important difference in certain of the known 'risk factors' such as serum cholesterol and blood pressure, or in two measures of the excitability of the myocardium (QT interval and the presence of extrasystoles). In this paper we present data relating to blood clotting and fibrinolysis.…”

mentioning

confidence: 92%

“…In an earlier study (Elwood et al, 1971) we presented data which showed no evidence of any important difference in certain of the known 'risk factors' such as serum cholesterol and blood pressure, or in two measures of the excitability of the myocardium (QT interval and the presence of extrasystoles). In this paper we present data relating to blood clotting and fibrinolysis.…”

mentioning

confidence: 92%

Blood clotting and fibrinolysis in areas with different water supplies.

Elwood¹,

Chadd²,

Burr³

et al. 1972

Journal of Epidemiology & Community Health

View full text Add to dashboard Cite

There is an apparent association between water hardness and mortality from cardiovascular disease (Kobayashi, 1957; Crawford, Gardner, and Morris, 1968). This association may arise because of an effect of water on a known 'risk factor' such as blood pressure, or the susceptibility of the myocardium could be affected, or some process relevant to intravascular thrombosis could be involved.In an earlier study (Elwood et al., 1971) we presented data which showed no evidence of any important difference in certain of the known 'risk factors' such as serum cholesterol and blood pressure, or in two measures of the excitability of the myocardium (QT interval and the presence of extrasystoles). In this paper we present data relating to blood clotting and fibrinolysis. METHOD Two villages, one of which has a hard water supply (350-380 p.p.m. total hardness) and the other a soft water supply (around 30-40 p.p.m.), were chosen. Random samples of male and female electors were selected and asked to co-operate.A sample of venous blood was taken from each subject. Some of this (5 ml) was mixed with fresh 3 * 8 % sodium citrate, 9 : 1 volumes blood to citrate, spun immediately at 3,000 r.p.m. for 10 minutes in a MSE centrifuge and the plasma was separated and deep frozen immediately. Two millilitres of blood were mixed with 20J1 of Trasylol and allowed to clot overnight, and then the serum was separated and deep frozen.Clinics were arranged on two days each week, one day in the hard and the other day in the soft water area, and the order of the clinics each week was alternate. Care was taken to ensure that the blood and serum samples were always handled in exactly the same way. Samples were numbered at random and submitted to the laboratory in batches of roughly equal numbers from the two areas. All laboratory work on the samples was therefore done without knowledge of the area of their origin, and all tests were completed within a few days of taking the blood.In order to obtain further data on fibrinolysis five other hard water areas (all with supplies over 240 p.p.m.) and five with soft water (all under 70 p.p.m.) were selected and a further 910 subjects were seen in exactly the same way as in the main study, though only estimations of fibrin degradation products were made.The tests used were the thrombin clotting time and the kaolin cephalin clotting time estimated by standard methods. Circulating fibrinogen and plasminogen were estimated by a modification of standard immunological methods of Wolf (personal communication); clotting fibrinogen was also estimated by the method of Farrell and Wolf (1971). Fibrin degradation products were estimated by the Wellcome modification of the methods of Murakami, Sekimoto, and Yasuda (1965) and Merskey, Kleiner, and Johnson (1966). Because the estimation of fibrinogen and plasminogen is tedious and supplies of the necessary immune sera are limited, these were made only on a subsample of the male subjects, chosen at random from all those seen. RESULTSThe number of subjects seen is shown in...

show abstract

Cardiovascular Surveys in Areas with Different Water Supplies

Cited by 21 publications

References 6 publications

Atherosclerosis and hypertension induction by lead and cadmium ions: an effect prevented by calcium ion.

Atherosclerosis and hypertension induction by lead and cadmium ions: an effect prevented by calcium ion.

Cardiovascular disease and environmental exposure.

Blood clotting and fibrinolysis in areas with different water supplies.

Contact Info

Product

Resources

About