Grip Strength, BMI and Mortality

[Guest guest]

Hi folks:

Here are some interesting data, from the abstract below:

Grip strength is periodically noted to be a biomarker for longevity.

The higher the better. Here are this study's mortality data broken

out by BMI and grip strength:

Mortality (Indexed to the rate for BMI 20-25 with stronger grip

strength as equal to 100)

------- ----- grip strength -----

------- weaker - medium - stronger

--BMI-- ------- -------- ---------

--<20-- --136-- --127--- ---92----

-20-25- --125-- --114--- --100----

--25+-- --139-- --127--- --114----

Observations:

These data indicate that: it is better to be stronger than weaker;

people with a BMI above 25 have highest mortality at each level of

grip strength! : ^ ))) ; people with BMI below 20 have high

mortality if they have weaker grip strength, but THE LOWEST MORTALITY

if they have good grip strength.

This looks very supportive of the idea that the higher mortality

often reported at low BMIs is a function of sub-clinical illness that

may often also be reflected in poor muscle strength.

Yes I know. Someone is gonna say that it suggests there may be a

benefit to exercise to increase muscle strength : ^ )))

====================================================================

J Gerontol A Biol Sci Med Sci. 2000 Mar;55(3):M168-73.

" Muscle strength and body mass index as long-term predictors of

mortality in initially healthy men. "

Rantanen T, T, Leveille SG, Visser M, Foley D, Masaki K,

Guralnik JM.

Epidemiology, Demography and Biometry Program, National Institute on

Aging, National Institutes of Health, Bethesda, land, USA.

Taina@...

" BACKGROUND: Muscle weakness, low body weight, and chronic diseases

are often observed in the same people; however, the association of

muscle strength with mortality, independent of disease status and

body weight, has not been elucidated. The aim was to assess hand grip

strength as a predictor of all-cause mortality within different

levels of body mass index (BMI) in initially disease-free men.

METHODS: Mortality was followed prospectively over 30 years. Maximal

hand grip strength tests and BMI assessments were done at baseline in

1965 to 1970. The participants were 6040 healthy men aged 45 to 68

years at baseline living on Oahu, Hawaii. RESULTS: The death rates

per 1000 person years were 24.6 in those with BMI <20, 18.5 in the

middle BMI category, and 18.0 in those with BMI > or = 25. For grip

strength tertiles, the mortality rates were 24.8 in the lowest, 18.5

in the middle, and 14.0 in the highest third. In regression

models, within each tertile of grip strength, BMI showed only minimal

effect on mortality. In contrast, in each category of BMI there was a

gradient of decreasing mortality risk with increasing grip strength.

Among those with BMI <20, the adjusted relative risks (RRs) of

mortality over 30 years were 1.36 (95% confidence interval 1.14-1.63)

for those in the lowest third of strength at baseline, 1.27 (1.02-

1.58) in the middle, and 0.92 (0.66-1.29) in the highest third.

Correspondingly, for those with BMI 20-24.99, the RRs of death were

1.25 (1.08-1.45), 1.14 (1.00-1.32), and 1.0 (reference) in the

lowest, middle, and highest third of grip strength, respectively. In

those with BMI > or =25, the RRs were 1.39 (1.16-1.65) in the lowest,

1.27 (1.08-1.49) in the middle, and 1.14 (0.98-1.32) in the highest

third of grip strength. Models were adjusted for age, education,

occupation, smoking, physical activity, and body height. CONCLUSIONS:

In healthy middle-aged men, long-term mortality risk was associated

with grip strength at baseline, independent of BMI. The possible

interpretation of the finding is that early life influences on muscle

strength may have long-term implications for mortality. Additionally,

higher strength itself may provide greater physiologic and functional

reserve that protects against mortality. "

PMID: 10795731

Rodney.