Background and objective: Evidence on the elevated cardiovascular risk associated with masked hypertension (MHT) is becoming stronger. Determining the prevalence of MHT in apparently healthy individuals may enable better risk stratification and management.
Methods: This was a cross-sectional study of normotensive healthcare workers recruited from 52 hypertension units. We included individuals aged at least 18 years with no known history of hypertension and office blood pressure (BP) less than 140/90 mmHg. MHT was defined as mean daytime ambulatory BP of at least 135/85 mmHg.
Results: Overall, 485 individuals (mean age 43.1 years, 55% women) were included. The prevalence of MHT was 23.9% [95% confidence interval (CI): 20.1-27.7]. The most prevalent associated cardiovascular risk factors in the total population were smoking (24.9%), dyslipidemia (16.4%), a family history of premature cardiovascular disease (15.9%), and obesity (7.4%). A total of 45.4% of individuals had a family history of hypertension. MHT was associated with male sex [odds ratio (OR) 1.722, 95% CI: 1.091-2.718] and prehypertension (OR 4.561, 95% CI: 2.880-7.222). In univariate analysis, the OR of the diagnosis of MHT increased by 2.3% per year of age.
Conclusion: The prevalence of MHT in normotensive healthcare workers in Spain is almost 25%. Therefore, 24-h ambulatory BP monitoring should be routine in occupational health checks in health workers, especially men.