Objectives

To explore the prognostic value of signs of prior myocardial infarction (MI) and atrial fibrillation (AF) on routine electrocardiograms (ECGs) at the age of 85 with respect to mortality and changes in functional status.

Design

Observational, prospective cohort study with complete 6-year follow-up.

Setting

General population.

Participants

A population-based sample of 566 85-year-old participants (377 women, 189 men), without exclusion criteria.

Measurements

Annual ECG recording and evaluation using automated Minnesota Coding; annual assessment of functional status using validated questionnaires and tests; complete mortality data from civic and national registries.

Results

Participants with prior MI at the age of 85 (prevalence 9%) showed greater all-cause mortality (relative risk (RR)=1.7, 95% confidence interval (CI)=1.2-2.2) and cardiovascular mortality (RR=2.5, 95% CI=1.6-3.8) but no accelerated decline in functional status during follow-up. Participants with AF at the age of 85 (prevalence 10%) showed greater all-cause (RR=1.5, 95% CI=1.2-2.0) and cardiovascular (RR=2.0, 95% CI=1.3-3.0) mortality, as well as an accelerated decline in functional status during follow-up.

Conclusion

Very elderly people with prior MI or AF on a routine ECG have markedly greater (cardiovascular) mortality risks. In addition, AF, but not prior MI, is associated with accelerated decline in functional status. These findings suggest that older patients with occasional findings of prior MI or AF on a routine ECG should receive optimal secondary preventive therapy. Furthermore, programmatic ECG recording could be of significant value for cardiovascular risk stratification in old age and needs further exploration.