Occupational and other risk factors for hand-grip strength: the Honolulu-Asia Aging Study

Background: In certain occupations, including farm work, workers are exposed to hazardous substances, some of which are known to be toxic to the nervous system and may adversely affect muscle strength. Measurement of hand-grip strength may be useful for detecting neurotoxic exposure. Methods: The authors studied 3522 participants of the Honolulu Heart Program and the Honolulu-Asia Aging Study to determine whether occupational exposures to pesticides, solvents, and metals assessed at exam I (1965 - 68) are associated with hand-grip strength at exam IV (1991 - 93) and change in hand-grip strength over 25 years. Correlation, analysis of variance and covariance, and linear regression were used to evaluate the associations. Results: At exam IV, participants ranged in age from 71 - 93 years; mean hand- grip strength was 39.6 kg at exam I and 30.3 kg at exam IV. Over 25 years, the decline in hand- grip strength was an average of 8 - 9 kg for all exposures. Hand-grip strength was inversely associated with age and glucose but directly associated with cognitive function, BMI, and haemoglobin level. No other exposures were associated with hand- grip strength. Conclusion: This study did not provide evidence that occupational exposure to pesticides, solvents, and metals adversely affected hand- grip strength in this population, but confirmed other important associations with hand- grip strength.