Did you ever consider whether a strong hand shake could be useful for more than intimidating the person you shake hands with? Turns out, hand grip strength may be a better predictor of cardiovascular and noncardiovascular death than current methods that measure systolic blood pressure.
Not Just a Catchy Slogan!
One Lancet publication has sparked a flurry of publications on hand shakes, but Dr. Leong insists that this is more of a “catchy slogan they are using to promote the story”.
Descriptions of the case, such as by the Daily Mail, might have missed the point:
A new study shows that a weak handshake may show a higher risk of a heart attack with the greater the loss of strength, the higher the risk.
“I’ve consistently said that there are a lot of social and cultural factors influencing someone’s handshake”, says Dr. Leong, “...the key message is that muscle strength is an important marker”.
We’re all familiar with the regular predictors of health: weight, blood pressure and cholesterol. This month’s Lancet publication suggested that grip strength may trump them all as a predictor of cardiovascular death - the number one global killer. WHO stats reveal that 3 in 10 deaths are attributable to cardiovascular-related problems.
This test also predicted risk of non-cardiovascular death, as well as the risk of having a stroke or heart attack. On top of that, the hand grip test predicted the chances of recovery from cancer and pneumonia.
The results were from the PURE study involving 17 countries from all income levels, totalling 142,861 people between 35 and 70 years old. This epidemiological study followed the participants throughout their lifetimes, and compared changes relative to a baseline measurement.
Why is this such a big deal?
Using a simple Jamar dynamometer (to measure grip strength of a person), this test involves squeezing the device as hard as you can, and can be completed in a few minutes. Because it is so cheap, it has huge potential as a predictive test in low income countries.
Grip strength is a simple, quick, inexpensive and reusable risk-stratifying method for all-cause death, cardiovascular death, and cardiovascular disease. This has excellent applications in low income countries.
How simple, quick, inexpensive and reusable is it?
Does this mean that you should run to the next gym to train your hand muscles?
In an interview with Dr. Leong, he emphasised that there is yet work to be done before applying it. Also, it is likely that hand grip is an indication of general muscle strength and it is important to work on the full body. Doing a giant hand work-out might not do the trick. Nor is it clear if actively improving muscle strength through exercise reduces the risk of mortality and disease.
Who Has the Strongest Grip?
Although it isn't fully clear what the association is between age, hand grip strength, and how this fits into the disease profiles found in the study above, epidemiological studies found that weaker grip strength in later life is associated with disability, morbidity, and mortality. An analysis that looked at grip strength across the life course found that males were on average stronger than females from adolescence onwards: males’ peak median grip was 51 kg between ages 29 and 39, compared to 31 kg in females between ages 26 and 42. Dr Leong said more work needed to be done on defining the healthy ranges and adapting them to ethnicity, age and gender.
Did Age Skew Your Data?
When do we have the strongest hand grip? Cross-cohort centile curves for grip strength
With billions of dollars pouring into the digital health market, there is a big question around if related applications really work. Finally, a systematic review and meta-analysis broke it down to look at the true impact.
It showed that digital health does, in fact, have a significant impact on reducing cardiovascular problems, particularly amongst people who already have an identified ailment. Interactive digital health, like those that using text messaging, were particularly effective.