Is Baseline Orthostatic Hypotension Associated With a Decline in Global Cognitive Performance at 4‐Year Follow‐Up? Data From TILDA (The Irish Longitudinal Study on Ageing)

BACKGROUND: It is postulated that orthostatic hypotension (OH), a reduction in blood pressure (≥20/10 mm Hg) within 3 minutes of standing, may increase cognitive decline because of cerebral hypoperfusion. This study assesses the impact of OH on global cognition at 4‐year follow‐up, and the impact of age and hypertension on this association. METHODS AND RESULTS: Data from waves 1 and 3 of TILDA (The Irish Longitudinal Study on Ageing) were used. Baseline blood pressure response to active stand was assessed using beat‐to‐beat blood pressure monitoring. Two measures of OH were used—at 40 seconds (OH40) and 110 seconds (OH110). Global cognition was measured using the Montreal Cognitive Assessment. Mixed‐effects Poisson regression assessed whether baseline OH was associated with a decline in global cognition at 4‐year follow‐up. The analysis was repeated, stratifying by age (age 50–64 years and age ≥65 years), and including an interaction between OH and hypertension. Baseline OH110 was associated with an increased error rate in Montreal Cognitive Assessment at follow‐up (incident rate ratio 1.17, P=0.028). On stratification by age, the association persists in ages 50 to 64 years (incident rate ratio 1.25, P=0.048), but not ages ≥65 years. Including an interaction with hypertension found those with co‐existent OH110 and hypertension (incident rate ratio 1.27, P=0.011), or OH40 and hypertension (incident rate ratio 1.18, P=0.017), showed an increased error rate; however, those with isolated OH110, OH40, or isolated hypertension did not. CONCLUSIONS: OH is associated with a decline in global cognition at 4‐year follow‐up, and this association is dependent on age and co‐existent hypertension.