Lower systolic blood pressure is associated with greater mortality in people aged 85 and older.
OBJECTIVE
To investigate the association between blood pressure and mortality in very old people.


METHODS
Population-based cohort study.


METHODS
County of Västerbotten, Sweden.


METHODS
Half of all subjects aged 85 and all of those aged 90 and 95 and older (N=348) in one urban and five rural municipalities in the north of Sweden.


METHODS
Among others, supine blood pressure, Mini-Mental State Examination, Barthel Index of activities of daily living, Mini Nutritional Assessment, and body mass index. Information on diagnoses, medications, and 4-year mortality was collected. Associations between blood pressure and mortality were investigated using Cox regression analyses, controlling for a number of diagnoses and health factors.


RESULTS
Baseline systolic blood pressure (SBP), diastolic blood pressure, and pulse pressure were all inversely associated with mortality within 4 years according to univariate analysis. SBP was the strongest predictor. In Cox regression analyses, low SBP (<or=120 mmHg) correlated with greater 4-year all-cause mortality alone and when controlling for health status. This connection persisted after exclusion of deaths within the first year. There was a tendency toward a U-shaped mortality curve for the adjusted model, with SBP of 164.2 mmHg (95% confidence interval=154.1-183.8 mmHg) being associated with the lowest mortality.


CONCLUSIONS
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.
Molander
Lena
L
Department of Community Medicine and Rehabilitation, Geriatric Medicine, Umeå University, Umeå, Sweden. lena.molander@germed.umu.se
Lövheim
Hugo
H
Norman
Tove
T
Nordström
Peter
P
Gustafson
Yngve
Y
D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D015897:Comorbidity; D005260:Female; D006801:Humans; D006973:Hypertension / Q000401:mortality; D008297:Male; D009026:Mortality; D012959:Socioeconomic Factors; D016019:Survival Analysis; D013548:Sweden / Q000453:epidemiology; D013599:Systole