Review of the benefits of treating hypertension.

The main points covered in this review are as follows: 1. Hypertension is a major determinant of cardiovascular disease (CVD). As such it is a major cause of mortality, potential years of life lost, morbidity and long-term disability. 2. The incidence of CVD is directly related to BP. It is likely that this extends over the full range of BP although some writers believe that a J-curve of risk exists for CHD. 3. The relationship between long-term disability from CVD and BP requires further study. 4. Because of regression dilution bias, the gradient in risk of stroke and CHD with BP has been underestimated in the past. Recent research suggests that the risk of stroke increases at least tenfold and CHD sixfold over a range of usual DBP of 30 mmHg (equivalent to approximately 50 mmHg baseline DBP). 5. The population attributable risk (PAR) of CVD related to general elevation of BP in the population from a mean daily excess of sodium intake of 100 mmol/day is at least 30%. In typical industrialised countries the PAR for stroke and CHD from clinical hypertension is 36% and 22%, respectively. These estimates of PAR provide a guide to the maximum benefit that could result from either restriction of sodium intake in the whole population or ideal management of all persons with hypertension. In practice such targets are unlikely to be realised. 6. Recent analyses of clinical trials of treatment of hypertension suggest that the risk of stroke is reduced at all levels of initial BP to the extent predicted from observational studies.(ABSTRACT TRUNCATED AT 250 WORDS)