Purpose
The study was conducted to investigate metabolic syndrome (MS) incidence within the normal blood pressure (BP) range in a population over 40 years old in an urban area of Guiyang, Guizhou Province, China, and to identify a valid BP cutoff value for predicting MS.
Materials and Methods
Data from this study are based on the Risk Evaluation of cAncers in Chinese diabeTic Individuals: a lONgitudinal (REACTION) study. In total, 2935 subjects in the normal BP range and without MS (795 males, 2140 females) aged 40–80 years were included in this study. Follow-up subjects were classified by baseline BP and grouped by age. After the 3-year follow-up, the MS incidence and valid BP cutoff value for predicting MS were calculated for subjects within the normal BP range.
Results
After the 3-year follow-up study, the crude and standardized MS incidences in the cohort were 19.83% and 16.89% for follow-up subjects, respectively, with incidences of 10.94% and 10.50% for males and 23.13% and 20.66% for females. The incidence of MS in normotensive subjects (15.53%) was lower than that in subjects with high-normal BP (29.08%). After adjusting for age, sex, BMI, smoking, and drinking, the risk of having MS in the high-normal BP group was 1.823-fold [HR 1.823 95% CI (1.538–2.162)] higher than that in the normotensive group. The ROC curve showed that the BP cutoff values were more than 117/74 mmHg in males and 112/74 mmHg in females.
Conclusion
When BP was within the normal range, the incidence of MS in participants was very high. The MS incidence was higher among high-normal BP subjects than among normotensive subjects, as was the risk of having MS. The valid BP cutoff value for predicting MS in the population was 117/74 mmHg in males and 112/74 mmHg in females. Currently, epidemiological investigations are needed to determine whether a lower BP cutoff value is needed in diagnosing MS.