Introduction: Homoeostatic blood pressure responses to standing play a pivotal role in identifying individuals at risk of syncope and unexplained falls. To date no study has examined the spectrum of beat-to-beat blood pressure responses and prevalence of orthostatic hypotension (OH) at a population level.
Methods: Participants (n = 4,463) were recruited from The Irish Longitudinal Study on Ageing, a nationally representative cohort study of Irish adults aged 50 and over. Analysis was applied to beat-to-beat blood pressure records from those who underwent an active stand test using continuous non-invasive photoplethysmography (Finometer™). Individuals were identified as having OH according to ESC guidelines. The spectrum of blood pressure profiles and prevalence of OH was reported across age, gender and at each time point following standing after reweighting for non-response.
Results: Drops in systolic blood pressure increase with age and are higher in females. Males: (50–59) 36.5 mmHg versus (80–89) 48.1 mmHg; females: (50–59) 42.8 mmHg versus (80–89) 49.1 mmHg (P < 0.05). The proportion of those with drops of >20 mmHg systolic and/or >10 mmHg diastolic within 3 min of standing was 97.8 % of males and 98.3% of females. The proportion of those with a sustained drop after 40 s of standing increased with age from 6.3% in males and 10.8% in females aged 50–59 to 32% of males and 29% of females in the over 80 s.
Conclusion: The proportion of those with OH using beat-to-beat technology is high according to the 20/10 definition. Timing of the response is important with over a quarter of oldest adults aged >80 demonstrating a sustained blood pressure drop after 40 s. The definition of OH requires refinement to include timing and response morphology to explicitly define a sustained drop.