[Impact of isolated diastolic hypertension on new-onset cardiovascular and cerebro-vascular diseases].

Objective: To explore the impact of isolated diastolic hypertension (IDH) on new-onset cardio-cerebral vascular diseases (CVD).

Methods: This cohort study involved 101 510 participants who were employees of the Kailuan Group-a state-run coal mining company, in 2006 and 2007. Among them, 6 780 subjects were diagnosed with IDH, 35 448 subjects were diagnosed with high-normal blood pressure and 19 460 subjects were diagnosed with normal tension. However, none of them had the history of either cardio-cerebral vascular disease or malignant cancer. Cardio-cerebral vascular events including cerebral infarction, cerebral hemorrhage, acute myocardial infarction were recorded every 6 months during the follow-up (47.1 ± 4.8) period. Multivariable Cox proportional hazards regression models were used to analyze the risk factors of first-ever CVD events.

Results: 1) There were 675 CVD events occurred during the follow-up period. The incidence rates of CVD events (1.7% vs. 0.9%), cerebral infarction (1.0% vs. 0.6%) and cerebral hemorrhage (0.4% vs. 0.1%) were significantly higher in IDH group than that in the normal tension group (all P < 0.05). 2) After adjustment for other established CVD risk factors, the hazards ratios became 1.67 (95% CI: 1.28-2.17) for total CVD events and 1.59 (95% CI: 1.12-2.27) for cerebral infarction and 2.67 (95% CI: 1.54-4.65) for cerebral hemorrhage in the IDH group. 3). In stratified analysis on age, after adjustment for other established CVD risk factors, the hazards ratio was 2.22 (95% CI: 1.41-3.50) for cerebral infarction in lower 60 years old group, while the it was 7.27 (95% CI: 2.58-20.42) for cerebral hemorrhage in groups older than 60 years of age.

Conclusion: IDH was the independent risk factor for the total cardio-cerebral vascular events, on both cerebral infarction and cerebral hemorrhage. The predicted values of IDH for different CVD events were diverse on different age groups.