Ambulatory blood pressure monitoring for evaluating the relationships between lifestyle, hypertension and cardiovascular risk.

1. Ambulatory monitoring provides a unique opportunity for studying the temporal relationships between lifestyle factors and blood pressure (BP). These include physical activity, mental activity, environmental stressors, substances ingested for pleasure such as smoking, alcohol and caffeine, and nutrition. 2. Changes in physical activity play a major role in determining the diurnal profile of BP, whereas the influence of mood is small. 3. Environmental stress, in the form of job strain, has been shown to be associated with a sustained increase of BP throughout the day and night in men, and also with an increased left ventricular mass. The effects are most marked in men who drink alcohol regularly. Job strain does not appear to influence BP in women. 4. Although it is recognized that smoking raises BP acutely, its long-term effects have been unclear. Ambulatory monitoring shows that smokers have a larger diurnal swing of BP than non-smokers, because of a higher daytime pressure. Alcohol also increases the diurnal swing of BP. 5. Ambulatory monitoring has been used relatively little for evaluating nutritional factors, but has the possibility of quantifying their effects on BP more reliably than traditional methods, and also elucidating the underlying mechanisms.