The associations of diastolic blood pressure with the risk of stroke in western and eastern populations
Ni Mhurchu C., Rodgers A., MacMahon S.
This paper reviews evidence from two overviews of prospective, observational studies of the association of diastolic blood pressure (DBP) with the risk of stroke in populations from the US and Europe and populations from China and Japan. The Western overview included seven studies involving a total of 405,511 individuals. During a mean follow-up period of 11 years, 843 strokes were observed. The Eastern overview included 18 cohorts involving a total of 124,774 participants. During a mean follow-up duration of 9 years, 1,798 strokes were observed. The shape of the association between usual DBP and the risk of stroke was similar in Western and Eastern populations, but in Eastern populations the size of the association was about 50% steeper than that in Western populations. This may be due, at least in part, to cerebral haemorrhage comprising a greater proportion of total stroke in Eastern populations. This finding, together with the high stroke rates in many Eastern Asian populations, suggests that the potential benefits of blood pressure lowering may be greater in Eastern Asia.