Research published in the journal Heart tracked the cardiovascular health of just under 3000 men for 16 years, and found that after controlling for other health factors including fitness level, men with higher resting heart rates had a higher risk of death. This analysis accompanied a roundup.
Title, Date of Publication & Journal
Elevated resting heart rate, physical fitness and all-cause mortality: a 16-year follow-up in the Copenhagen Male study, 15 April 2013, Heart.
Claim supported by evidence?
The paper demonstrates an increased risk of mortality in later years amongst healthy males amongst those with a higher Resting heart Rate (RHR).
This apparent risk factor is shown to be independent of physical fitness, leisure time physical activity and other major cardiovascular risk factors.
In line with previous studies, smoking was more common amongst those with low RHR, and there was some suggestion that the risk from high RHR was greatest in those who smoked.
There was no direct evidence that lowering your HRH improved life expectancy.
Well controlled long term study carried out in a healthy worker population.
Less than a half of those invited to take part in the original study in 1970-71 appear in the analysis. About 20% were non-responders at the second examination in 1985-86.
All hazard ratios in Table 2 are comparison to the lowest RHR group (<50bpm), which is the most extreme 8% of the subjects studied. As a result the paper and especially the press release stresses increased mortality, while in fact this represents the reduced mortality in this extreme group with low RHR.
Conclusions in paper are well supported and carefully presented.
The press release is confusing in that it presents hazards ratios compared to the most extreme subgroup, and as a result stresses high mortality rates.
Table 1 is confusing as the number of subjects’ column (n) is misaligned. See table 2 instead.
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