Worldwide trends in alcohol and drug impaired driving.

Improved laws, enhanced enforcement, and public awareness brought about by citizens' concern, during the 1980s led to dramatic declines in drinking and driving in the industrialized world. The declines included about 50% in Great Britain, 28% in The Netherlands, 28% in Canada, 32% in Australia, 39% in France, 37% in Germany, and 26% in the United States. Some of these declines may be due in part to lifestyle changes, demographic shifts, and economic conditions. In most countries the declines reversed in the early 1990s and drinking and driving began to increase. By the middle of that decade the increases stabilized and the rates of drinking and driving again began to decline. These decreases were much less dramatic than those in the 1980s. Approaching the end of the 1990s and early in the new century, the record has been mixed. Some countries (France and Germany (until 2002)) continued to reduce drinking and driving while in other countries (Canada, the Netherlands, Great Britain, and the United States), there was stagnation and in some cases small increases or even large increase as was the case in Sweden. Complacency and attention to other issues in recent years have been difficult to overcome in some countries. Harmonization of traffic safety laws in the European Union has strengthened laws in some countries but threatens existing strong policies in others. It may be that the major gains have already been made and that additional progress will require a much greater level of scientific knowledge, use of new and emerging technologies, and political and social commitment to put in place proven countermeasures.

Evaluation of screening for hypertension in general practice with an automatic machine.

An automatic device for measuring blood pressure was used to screen all patients aged 30 to 65 years registered at a health centre. Of those who were eligible, 55% attended. Patients with previously recognised hypertension were more common among the attenders than among the non-attenders. High readings obtained on the automatic device possibly deterred some patients from reattending for follow up measurements of blood pressure. Although the device is quick and easy to use, the logistic challenge of formal blood pressure screening is considerable. Hypertension was discovered in 52 patients (mean diastolic pressure greater than 100 mm Hg). Retrospective analysis of their medical records showed that a third had had an abnormal blood pressure reading noted during the past 10 years and no further action had been taken, and almost three quarters had attended their practitioner during the previous year without having a blood pressure measurement recorded. One year after the screening procedure two fifths of the newly discovered hypertensive patients had defaulted from follow up and treatment. Automatic devices are not a short cut to the discovery of occult hypertension. Case finding by routine measurement of blood pressure at surgery visits is more efficient.

Pregnancy-associated hypertension, a comparison of its prediction by 'roll-over test' and plasma noradrenaline measurement in 100 primigravidae.

One hundred primigravidae had a 'roll-over test' between 28 and 32 weeks of gestation. Of the 10 women with positive results (a rise of greater than or equal to 20 mmHg in diastolic blood pressure after roll-over) only two later developed diastolic blood pressures greater than 90 mmHg. Of the 90 patients with a negative result, 17 subsequently sustained diastolic pressures of greater than 90 mmHg. The change in plasma noradrenaline levels measured before and after roll-over, in all patients, did not distinguish between those patients who remained normotensive and those who subsequently developed hypertension. At 28-32 weeks gestation, those patients who subsequently developed hypertension had a higher mean plasma noradrenaline level and a higher systolic blood pressure than the patients who remained normotensive.

Plasma noradrenaline in normal pregnancy and in hypertension of late pregnancy.

Plasma noradrenaline was measured by radioenzymatic assay on 90 occasions in 72 women throughout normal pregnancy. Plasma noradrenaline levels declined as pregnancy advanced. A total of 21 patients who developed hypertension in late pregnancy were found to have plasma noradrenaline levels significantly lower than controls at the same stage of pregnancy. It is concluded that plasma noradrenaline is reduced in hypertension of late pregnancy. This indicates a compensatory reduction in sympathetic nervous system activity.

Ethnic differences in blood pressure with observations on noradrenaline and renin. A hospital hypertensive population.

100 patients with essential hypertension (77 whites, 23 black) were studied with measurements of plasma noradrenaline concentration and plasma renin activity. Black patients had higher blood pressure than whites. There were no ethnic differences in mean plasma noradrenaline, but plasma renin activity was lower in blacks than whites, and this difference was not related to differences in sodium intake. Plasma noradrenaline increased with age in blacks, and in a white control group. Young white hypertensive patients (< 45 years) had higher plasma noradrenaline than controls, and in white hypertensives plasma noradrenaline was positively correlated with plasma renin.

Are racial differences in essential hypertension due to different pathogenetic mechanisms?

1. Plasma noradrenaline concentration and plasma renin activity were measured in a control, British, urban population (n = 115) in which blacks were matched for age and sex with whites. 2. Similar measurements were made in subjects with essential hypertension (77 white and 23 black), and 48 healthy normotensive white civil servants. 3. In controls blood pressure was significantly higher in blacks; it correlated with age in both races and with pulse rate in blacks. There were no significant racial differences in plasma noradrenaline which was positively correlated with age in both blacks and whites. Mean plasma renin activity was 55% lower in blacks, and this difference was not related to urinary sodium excretion. 4. In hypertensive subjects plasma noradrenaline positively correlated with age in blacks. This relationship was not found in whites in whom 20% of young hypertensive subjects (less than 45 years) had significantly raised plasma noradrenaline. Plasma renin activity was again significantly lower in blacks. In white hypertensives plasma noradrenaline and renin activity were significantly correlated. 5. There may be racial differences in the pathogenesis of essential hypertension.

Plasma-noradrenaline in essential hypertension.

Plasma-noradrenaline (P.N.A.) has been determined in normotensive controls and in patients with essential hypertension while resting and after postural stimulation. A linear relationship was found between age and P.N.A. in normotensives during recumbency and in the upright posture. This relationship did not occur in the hypertensives and was due to raised P.N.A. levels in many younger patients. On standing, ten out of thirty-four patients under the age of 50 years with essential hypertension had significantly greater P.N.A. than the age-matched controls. No differences were found, however, between controls and patients in the older age-group. It is proposed that stimulation of the sympathetic nervous system by postural challenge provides a means for identifying a subgroup of younger patients with essential hypertension in whom sympathetic overactivity may play an important rule.

Reliability and cost of diabetic diets.

In 1968 the actual food intake of 63 diabetic patients was recorded for a period of one week. The food consumption of 19 was found to be within 10% of that which had been prescribed for them at the diabetic clinic, but the food actually eaten by many of the other patients differed appreciably from the prescribed diet. Dietary control was more reliable in the younger patients and in those who required insulin. In many patients the food intake varied widely from day to day.There was no obvious relation between the reliability of dietary control during this survey and the standard of diabetic control as recorded in the diabetic clinic. The findings of this survey were compared, where possible, with the results of a previous and similar survey conducted in 1948. In both surveys it was confirmed that the cost of the diet per week for diabetics was above that for the general population.