What is the clinical evidence from this study?

Study design: Cohort. Population: First acute myocardial infarction (n=26163). Intervention: Estimated cardiorespiratory fitness (eCRF) highest tertile vs. Lowest tertile of eCRF. Primary outcome: First acute myocardial infarction (AMI) (SHR 0.75 (women) / SHR 0.90 (men), 95% CI 0.60-0.95 (women) / 0.77-1.05 (men)).

April 17, 2019Open Access

Cardiorespiratory Fitness and the Risk of First Acute Myocardial Infarction: The HUNT Study

Key Result

High estimated cardiorespiratory fitness was associated with a 25% lower risk of first acute myocardial infarction in women (SHR 0.75; 95% CI 0.60-0.95), but not significantly in men.

Study Design

Type

Cohort (n=26,163)

Structured PICO

Does high estimated cardiorespiratory fitness reduce the risk of first acute myocardial infarction in adults without baseline cardiovascular disease?

Population

26,163 participants from the HUNT study (Nord-Trøndelag Health Study), mean age 55.7 years, 51.5% women, without cardiovascular disease at baseline.

Intervention

Highest tertiles of estimated cardiorespiratory fitness (eCRF)

Comparator

Lowest tertile of estimated cardiorespiratory fitness (eCRF)

Outcome

First acute myocardial infarction (AMI)hard clinical

Higher estimated cardiorespiratory fitness is associated with a significantly reduced risk of first acute myocardial infarction in women, highlighting its value as a cardiovascular risk marker.

Main Result

Effect estimate: SHR 0.75 (women) / SHR 0.90 (men) (95% CI 0.60-0.95 (women) / 0.77-1.05 (men))

Abstract

Background The majority of studies evaluating cardiorespiratory fitness ( CRF ) as a cardiovascular risk factor use cardiovascular mortality and not cardiovascular disease events as the primary end point, and generally do not include women. The aim of this study was to investigate the association of estimated CRF ( eCRF ) with the risk of first acute myocardial infarction ( AMI ). Methods and Results We included 26 163 participants (51.5% women) from the HUNT study (Nord-Trøndelag Health Study), with a mean age of 55.7 years, without cardiovascular disease at baseline. Baseline eCRF was grouped into tertiles. AMI was derived from hospital records and deaths from the Norwegian Cause of Death Registry. We used Fine and Gray regression modeling to estimate subdistribution hazards ratio ( SHR ) of AMI , accounting for competing risk of death. During a mean (range) follow-up of 13 (0.02-15.40) years (347 462 person-years), 1566 AMI events were recorded. In fully adjusted models men in the 2 highest eCRF had 4% ( SHR : 0.96, 95% CI : 0.83-1.11) and 10% ( SHR : 0.90, 95% CI : 0.77-1.05) lower SHR of AMI , respectively, when compared with men in the lowest tertile. The corresponding numbers in women were 12% ( SHR : 0.88, 95% CI : 0.72-1.08) and 25% ( SHR : 0.75, 95% CI : 0.60-0.95). Conclusions eCRF was inversely associated with risk of AMI event among women but not in men. Our data suggest that high eCRF may have substantial benefit in reducing the risk of AMI . Therefore, our data suggest that an increased focus on eCRF as a cardiovascular disease risk marker in middle-aged and older adults is warranted.