Proposal of reference value for day-to-day blood pressure variability based on two outcomes: the Ohasama study.

BACKGROUND: This study aimed to propose reference values for day-to-day home blood pressure (BP) variability that align with the established hypertension threshold of home BP for the risk of two different outcomes: cardiovascular mortality and cognitive decline. METHODS: This prospective study was conducted in Ohasama town, Japan, with 1212 participants assessed for cardiovascular mortality risk (age: 64.7 years, 33.6% men). Additionally, 678 participants (age: 62.7 years, 31.1% men) were assessed for cognitive decline risk (Mini-Mental Scale Examination score <24). The within-individual coefficient of variation of home morning SBP (HSBP) was used as the index of day-to-day BP variability (%). Adjusted Cox regression models were used to estimate the HSBP-CV values, which provided the 10-year outcome risk at an HSBP of 135 mmHg. RESULTS: A total of 114 cardiovascular deaths and 85 events of cognitive decline (mean follow-up:13.9 and 9.6 years, respectively) were identified. HSBP and HSBP-coefficient of variation (HSBP-CV) were associated with increased risks for both outcomes, with adjusted hazard ratios per 1-standard deviation increase of at least 1.25 for cardiovascular mortality and at least 1.30 for cognitive decline, respectively. The adjusted 10-year risks for cardiovascular mortality and cognitive decline were 1.67 and 8.83%, respectively, for an HSBP of 135 mmHg. These risk values were observed when the HSBP-CV was 8.44 and 8.53%, respectively. CONCLUSION: The HSBP-CV values indicating the 10-year risk of cardiovascular mortality or cognitive decline at an HSBP of 135 mmHg were consistent, at approximately 8.5%. This reference value will be useful for risk stratification in clinical practice.

Changes in physical activity during the year after the Great East Japan Earthquake and future frailty in older survivors.

AIM: This study examines whether changes in physical activity (PA) during the first year after the Great East Japan Earthquake and Tsunami (2011-2012) contributed to preventing the onset of future frailty among older survivors of the disaster. METHODS: This study tracked 2561 physically active Japanese survivors aged ≥ 65 years (43.6% men; mean age 72.9 years) who had completed self-administered questionnaires in 2011 and 2012. PA levels for participants were classified into four categories based on ≥23 and <23 metabolic equivalent hours/week in 2011 and 2012: "consistently low," "decreasing," "increasing," and "consistently high." Frailty was defined as a Kihon Checklist score ≥ 5, which is used in the long-term care insurance system in Japan. Hazard ratios were calculated for the onset of frailty using a Cox proportional hazards model that fitted the proportional sub-distribution hazards regression model with weights for competing risks of death. RESULTS: From 2012 to 2018, 283 men and 490 women developed frailty. Men with consistently high or increasing PA during the first year after the disaster had a lower risk of frailty. Furthermore, even increasing PA by walking for just 30 min/day prevented future frailty in men; however, this association between a change in PA and the decreased risk of frailty was not observed in women. CONCLUSIONS: Older men who remained physically active or resumed PA at an early stage and at a low intensity, even after being physically inactive owing to the disaster, were able to prevent future frailty. Geriatr Gerontol Int 2024; 24: 563-570.