Temporal dynamics of blood pressure, functional status and cognitive function in adults aged 85 years and older: a dynamic time warping approach in the Leiden 85-plus study

Abstract Introduction High blood pressure (BP), functional decline, and cognitive decline commonly co-occur in late life. The temporal dynamics between changes in BP and changes in functional or cognitive status remain unclear. The aim of this study is to explore these temporal dynamics in adults aged 85 years and older using dynamic time warping (DTW). Methods This study used data from the Leiden 85-plus Study. BP, functional status and cognitive function were measured at baseline (age 85) and annually over 5 years. Participants with at least three measurements were included (n = 429 of 599). Functional status was assessed using the Groningen Activity Restriction Scale for Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL). Cognitive function was measured with the Mini-Mental State Examination (MMSE). DTW was applied to assess temporal relationships. Results The 429 participants were all aged 85 years at baseline, 69% were female and 39% used antihypertensive medication. Increases in BP over time were associated with later IADL decline, while BP decreases were associated with later IADL improvement (P .05). Similarly, decreases in diastolic BP over time were associated with later decreases in MMSE, while increases in diastolic BP were linked to later improvements in MMSE (P .05). Conclusion BP changes were associated with subsequent inverse IADL changes over time, while changes in diastolic BP preceded concordant changes in cognitive function. These findings highlight the importance of BP changes in old age, as they might indicate later functional or cognitive decline.