Research in Medicine

Background: we investigated the association of different hypertension subgroups including isolated systolic hypertension (ISH), isolated diastolic hypertension (IDH), systolic-diastolic hypertension (SDH), controlled blood pressure (CBP), and uncontrolled blood pressure (UBP) for incident CVD and mortality events.

Methods: 6974 middle age and 882 elderly participants were categorized according to their BP measurements, participants. Cox regression analysis was used to estimate the hazard ratio (HR) for hypertension subgroups, considering those with normotension as the reference.

Results: During more than 10 years of follow-up, in the middle-aged group, 490 CVD and 152 deaths occurred; corresponding rates for the elderly group were 194 and 176, respectively. In middle-aged subjects ISH, SDH and UBP increased the risk of CVD; whereas UBP increased the risk of mortality due to CVD and any cause (HR: 5.66 and HR: 2.95, respectively) and IDH increased only the risk of total mortality in this group (HR; 2.01) (all p-values <0.05). In elderly subjects ISH and UBP significantly increased the risks of CVD; whereas IDH, SDH 3.27 and and CBP increased the risks of CVD and all-cause mortality in this group, respectively (all p-value <0.05).

Conclusions: In both middle-aged and elderly population, ISH, SDH and UBP increase the risk of CVD. Controlling of BP to < 140/90 mm Hg decreases the risk of mortality events among middle-age population; however, not suitable for elderly as it was associated with higher risk of mortality.