A blood pressure clinic in a health centre

Mortality amongst patients of the Glasgow Blood Pressure Clinic was high in the 1970s and 80s but has fallen since, why?

Established in 1968 the Glasgow Blood Pressure Clinic has over 11,000 patients on its computer record. Up to 1980, mortality from all-causes and from cardiovascular causes was high: relative risks compared with two local control populations were greater than 2.0. Since 1980, all-cause mortality has decreased to 1.31 (859 deaths, CI 1.23-1.39). Lower mortality from cardiovascular causes, particularly coronary heart disease, contributes to the decrease. Reasons for the decrease are under investigation currently. Referral of patients with slightly lower blood pressure contributes, as may better blood pressure control with newer antihypertensive drugs. ACE inhibitors and calcium channel blockers were introduced in 1980 and during the 16-year period to 1995, all-cause mortality has decreased most in patients taking ACE inhibitor. A decrease also occurred in patients taking antihypertensive drugs other than ACE inhibitor.

Management of hypertension in twelve Oxfordshire general practices

The general practice records of 2371 hypertensive patients on drug therapy in 12 practices were reviewed retrospectively. It was found that the mean systolic blood pressure of the patients had fallen by 29 mmHg and the mean diastolic pressure by 16 mmHg after one year of treatment and that there was a further reduction of 5 mmHg in the systolic pressure and 5 mmHg in the diastolic pressure at the most recent recording of blood pressure. Half of the patients had only a single blood pressure reading recorded before treatment was started and for 56% of the patients there was no record of smoking habit and for 69% no record of weight. Twenty-seven per cent of the patients suffered from mild hypertension, that is blood pressure less than 180/110 mmHg, and 56% were over 65 years of age. These results indicate the need for policies for selection of patients for treatment and for standards of recording. It is suggested that practices should review their results and undertake to treat elderly hypertensive patients and those with mild hypertension only when they can demonstrate that their policies are effective for young hypertensive patients and for those with moderate or severe hypertension.

Community programme for control of hypertension in North Karelia, Finland

A community-based programme to improve awareness and control of hypertension was launched in 1972 in North Karelia. It was incorporated in the existing health-services system. An assessment five years later showed that, compared with a reference area not included in the programme, awareness of hypertension had improved, the prevalence of hypertension had dropped, levels of blood-pressure were lower by age-group, and the number of people on antihypertensive treatment had increased.

Salt and blood pressure in Scotland

Dietary salt intake and urinary sodium excretion were compared in normotensive and hypertensive subjects in Renfrew, Scotland. All groups had high 24-hour urinary salt excretions, and hypertensive subjects did not eat or excrete more salt than normotensive subjects. The only significant relations found were a lower sodium excretion in hypertensive women than in normotensive women (p < 0.02) and a lower urinary sodium concentration in hypertensive men than in normotensive men (p < 0.05). These data provide no support for the hypothesis that dietary salt is a major cause of hypertension.

Alcohol and hypertension

Liver-function data were compared in 158 unselected hypertensives and 105 normotensives aged 45-64 years. Serum concentrations of alanine and aspartate aminotransferase (S.G.O.T. and S.G.P.T.) were higher, and more often raised, in the hypertensive patients. Serum bilirubin and alkaline phosphatase concentrations were similar in both groups. In hypertensive patients aminotransferase concentrations tended to be higher in those with increased alcohol intake.

Blood-cadmium in hypertensives and normotensives

70 hypertensive patients and 70 controls matched for age and sex were investigated for a possible relationship between blood-cadmium and hypertension. No significant differences between the two groups were detected, although the blood-cadmium level was significantly higher in smokers as compared to non-smokers. These data do not support the hypothesis that cadmium is involved in the development of hypertension in man.