title: Ambulatory Blood Pressure Variability Increases Over a 10-Year Follow-Up in Community-Dwelling Older People.
abstract: BACKGROUND
  Greater ambulatory blood pressure variability (ABPV) is associated with end-organ damage and increased mortality. Age-related changes in the cardiovascular and autonomic nervous systems make age-associated increases in ABPV likely. Cross-sectional studies support this hypothesis, showing greater ABPV among older compared to younger adults. The only longitudinal study to examine changes in ABPV, however, found ABPV decreased over 5 years follow-up. This unexpected observation probably reflected the highly selected nature of the study participants.
  
  
  METHODS
  In this longitudinal study, we assessed changes in ABPV over 10 years in a community-cohort of older people. In addition, we examined the extent to which ABPV was predicted by demographics, cardiovascular risk factors, and medication. Clinical examination and 24-hour ambulatory blood pressure monitoring were carried out at baseline and at 10 years follow-up in 83 people, median age 70 years. ABPV was calculated using SD and coefficient of variation (Cv). Three time periods were examined: daytime, nighttime, and 24 hours.
  
  
  RESULTS
  Daytime and 24-hour, systolic and diastolic, SD, and Cv were significantly greater at follow-up than at baseline (P < 0.001 in all cases). Mean BP did not change.
  
  
  CONCLUSIONS
  Multilevel modeling showed follow-up interval had a significant, positive effect on SD and Cv (P < 0.004), independent of age, sex, and medication.ABPV increased over a 10-year follow-up despite stable mean BP. ABPV may therefore be an additional target for treatment in older people. Future studies should examine what degree of ABPV is harmful and if control of ABPV reduces adverse outcome.
authors: Institute of Cellular Medicine, Newcastle University, Newcastle, UK; Newcastle Hospitals NHS Foundation Trust, Newcastle, UK; Claire.mcdonald@ncl.ac.uk.
authors: Claire
authors: C
authors: McDonald
authors: Institute of Health & Society, Newcastle University, Newcastle, UK;
authors: Mark S
authors: MS
authors: Pearce
authors: Institute of Neuroscience, Newcastle University, Newcastle, UK.
authors: Joanna
authors: J
authors: Wincenciak
authors: Institute of Cellular Medicine, Newcastle University, Newcastle, UK; Newcastle Hospitals NHS Foundation Trust, Newcastle, UK;
authors: Simon R J
authors: SR
authors: Kerr
authors: Institute of Cellular Medicine, Newcastle University, Newcastle, UK; Newcastle Hospitals NHS Foundation Trust, Newcastle, UK;
authors: Julia L
authors: JL
authors: Newton
mesh_terms: D000367:Age Factors; D000368:Aged; D000375:Aging; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D002940:Circadian Rhythm; D004739:England; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D057187:Independent Living; D008137:Longitudinal Studies; D008297:Male; D015233:Models, Statistical; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors
keywords: aging; ambulatory blood pressure variability; blood pressure monitoring; hypertension; longitudinal study.