Postural hypotension and dizziness in a general aged population: a four-year follow-up of the Helsinki Aging Study.

OBJECTIVE

To evaluate the frequency, risk factors, and prognostic significances of postural hypotension (PH) and dizziness on postural testing (DPT).

DESIGN

A prospective cohort study.

SETTING

General community, The Helsinki (Finland) Aging Study.

SUBJECTS

Persons of three age cohorts (75, 80, and 85 years, n = 569) were chosen randomly and followed for 4 years.

MEASURES

Postal questionnaires, structured interview, extensive clinical and laboratory examinations, blood pressure (BP) changes in a postural test using different definitions for PH, history of dizziness, dizziness on testing postural blood pressure reactions (DPT), and date of death during a 4-year follow-up.

RESULTS

The frequency of a fall in systolic blood pressure greater than 20 mm Hg or a fall in diastolic pressure greater than 10 mm Hg (PH-I) was 30.3%. Both criteria occurred simultaneously (PH-II) in 7.5%, and if dizziness on postural testing (DPT) was an additional symptom (PH-III), the prevalence was 2.6%. The overall prevalence of DPT was 19.7%. PH-I, PH-II, and DPT were also frequent among the healthy aged (26.6%, 6.6%, and 17.3%, respectively). The postural change in BP correlated inversely with the initial supine BP levels (systolic r = -.149, P < .001 and diastolic r = -.218, P < .001), but in persons with isolated systolic hypertension PH was rather less frequent (21.9% and 2.3%). DPT was more common in the subjects with heart failure (26.3%, P < .05), impaired exercise tolerance (NYHA III-IV) (33.7%, P < .05), and PH-II (37.2%, P < .05) compared with the healthy controls (17.3%). The 1-year mortality was higher in subjects with than without DPT (7.1% vs 4.8%, P < .05), but the difference was not significant after controlling for age and gender. PH-I, PH-II, and PH-III were not significantly related to 4-year mortality.

CONCLUSIONS

In this study of older people in Helsinki, Finland, asymptomatic hypotensive postural BP reactions and DPT were found frequently among healthy older people, and they tended to be increased in people with some diseases. Neither PH nor DPT were of prognostic significance for mortality in this population.