Do Nationally Representative Cutpoints for Clinical Muscle Weakness Predict Mortality? Results from Nine Years of Follow-up in the Health and Retirement Study.

TitleDo Nationally Representative Cutpoints for Clinical Muscle Weakness Predict Mortality? Results from Nine Years of Follow-up in the Health and Retirement Study.
Publication TypeJournal Article
Year of PublicationForthcoming
AuthorsDuchowny, KA
JournalJournals of Gerontology, Series A: Biological Sciences and Medical Sciences
ISSN Number1758-535X
KeywordsCut points, Health Conditions and Status, Mortality
Abstract

Background: Muscle weakness, as measured by handgrip strength, is associated with cardiovascular and all cause-mortality; however, there are wide inconsistences in the magnitude of these effects due to divergent definitions used to define muscle weakness across studies. Therefore, the objective of this study was to examine the relationship between previously defined sex- and race-specific cutpoints of clinical muscle weakness and early mortality.

Methods: Data come from the 2006-2014 Health and Retirement Study. Time-varying clinical muscle weakness, as defined by handgrip strength cutpoints, was the primary exposure. Time to death, ascertained from the National Death Index, was the outcome of interest. The association between time-varying clinical muscle weakness and early mortality across a 9-year observation period was determined using Kaplan-Meier methods and extended Cox regression.

Results: Out of the 8,326 individuals in the study, 1,799 deaths (21%) occurred during the observation period. Median follow-up time was 8.3 years (SD ±1.9 years). Weak individuals had a steeper decline in their survival trajectory, compared to non-weak individuals (Log-Rank test, p<.001). After adjusting for sociodemographic factors and time-varying smoking history, weak individuals were over 50% more likely to die earlier than non-weak individuals (HR=1.52, 95% CI= 1.15, 1.47).

Conclusions: This is the first study to use muscle weakness cut-points derived in a nationally-representative sample to identify those individuals who may be at greatest risk for premature mortality. Results underscore the importance of muscle weakness, as defined by handgrip strength, as a key risk factor for premature mortality in older Americans.

DOI10.1093/gerona/gly169
User Guide Notes

http://www.ncbi.nlm.nih.gov/pubmed/30052779?dopt=Abstract

Alternate JournalJ. Gerontol. A Biol. Sci. Med. Sci.
Citation Key9813
PubMed ID30052779