Low systolic blood pressure and mortality in elderly

• hypertension is a thoroughly studied and well-documented risk factor for cardiovascular disease, such as myocardial infarction, heart failure, and stroke
• blood pressure, as well as the prevalence of hypertension, has been shown to rise with age
• however systolic hypotension in the elderly is more prevalent in the very elderly population
  • in a Swedish study, systolic blood pressure (SBP) increased until aged 75 to 79 and then decreased, whereas diastolic blood pressure (DBP) started to decrease earlier (1)
  • low blood pressure in the very elderly is associated with increased mortality
    • a number of studies have suggested a correlation between low, as opposed to high, blood pressure and mortality in the very elderly population (2,3,4)
    • studies exclusively designed for individuals aged 85 and older have suggested that low blood pressure is a predictor of death on its own, regardless of health status
  • a large population based cohort study revealed that (4)
    • lower SBP seems to be associated with greater mortality in people aged 85 and older, irrespective of health status
      • there are indications of a U-shaped correlation between SBP and mortality, and the optimal SBP for this age group could be above 140 mmHg.

Reference:

1. Lernfelt B, Svanborg A. Change in blood pressure in the age interval 70-90. Late blood pressure peak related to longer survival. Blood Press 2002;11:206-212.
2. Satish S, Freeman DH Jr., Ray L et al. The relationship between blood pressure and mortality in the oldest old. J Am Geriatr Soc 2001;49:367-374.
3. Hakala SM, Tilvis RS, Strandberg TE. Blood pressure and mortality in an older population. A 5-year follow-up of the Helsinki Ageing Study. Eur Heart J 1997;18:1019-1023.
4. Molander L, Lövheim H, Norman T, Nordström P, Gustafson Y. Lower systolic blood pressure is associated with greater mortality in people aged 85 and older. J Am Geriatr Soc. 2008 Oct;56(10):1853-9.