Objective: Approximately 10-20% of the general population have masked hypertension. However, how best to identify affected individuals is uncertain, and what predicts future masked hypertension is largely unknown. This study aimed to identify longitudinal predictors of masked hypertension.
Methods: A long-term follow-up study of 100 healthy young men who had normal (n = 28) or high (n = 72) screening blood pressure (BP) at the compulsory military draft was carried out. They were examined in a detailed and highly standardized way for cardiovascular risk markers at baseline and at follow-up after a mean of 17.4 years.
Results: At follow-up, 40% had masked hypertension. Participants with high screening BP had a 4.8 times higher likelihood of having masked hypertension at follow-up compared to men with low screening BP (odds ratio 4.8, 95% confidence interval 1.7-13.5, p = 0.003). Furthermore, only 25% of the men with masked hypertension had high normal office BP at follow-up, and the remaining 75% would, according to guidelines, not be recommended ambulatory BP measurements, and thus go undiagnosed.
Conclusion: Our data suggest that high screening BP at a young age is an important predictor of future masked hypertension in young men, and that BP measurement according to guidelines is insufficient to uncover masked hypertension.
Keywords: Ambulatory blood pressure monitoring; cardiovascular diseases; follow-up study; masked hypertension; risk factors.