Hypertension and prehypertension can increase the risk of developing cardiovascular disease (CVD) and diabetes. However, whether the harmful effects of high blood pressure (BP) are also seen with high normotension remains unknown. This 10-year longitudinal follow-up study aimed to investigate the relationships among normal-range BP, metabolic syndrome (MetS), and CVD.
A total of 9133 nonmedicated normotensive participants, 4634 males and 4499 females, aged 60 years or older were enrolled in a standard health examination program at 2 academic hospitals and a health screening center in Taiwan. The study subjects were divided into 3 groups according to their BP. The systolic BP (SBP) ranges of groups 1, 2, and 3 were 91 to 100, 101 to 110, and 111 to 119 mmHg, whereas the diastolic BP (DBP) ranges of groups 1, 2, and 3 were 51 to 60, 61 to 70, and 71 to 79 mmHg, respectively.
In the SBP3 group, both sexes had a higher odds ratio (OR) for having MetS or abnormal MetS components, except for triglycerides. Females in the DBP3 group had a higher OR for having MetS at baseline. After the follow-up period, the SBP3 group had a significantly higher hazard ratio (HR) for developing MetS. Males in the DBP3 group and females in the DBP2 and DBP3 groups had a significantly higher HR for developing MetS. Neither the SBP3 group nor the DBP3 group had a higher HR for developing nonfatal CVD. In the Kaplan-Meier analysis, SBP and DBP in both sexes showed statistical significance as predictors of MetS, but not of nonfatal CVD.
High normotensive elderly individuals have an elevated risk of developing MetS at baseline and within 10 years of follow-up, but they are not at increased risk of CVD. Preventive interventions, such as life-style modification, should be offered early even to the apparently healthy elderly.