|Title||Physical Functioning Decline and Mortality in Older Adults with Multimorbidity: Joint Modeling of Longitudinal and Survival Data.|
|Publication Type||Journal Article|
|Year of Publication||2019|
|Authors||Wei, MY, Kabeto, MU, Galecki, AT, Langa, KM|
|Journal||Journals of Gerontology Series A: Biological Sciences & Medical Sciences|
|Keywords||Comorbidity, Mortality, Physical Ability|
Background: Multimorbidity is common among older adults and strongly associated with physical functioning decline and increased mortality. However, the full spectrum of direct and indirect effects of multimorbidity on physical functioning and survival has not been quantified. We aimed to determine the longitudinal relationship of multimorbidity on physical functioning and quantify the impact of multimorbidity and multimorbidity-attributed changes in physical functioning on mortality risk.
Methods: The Health and Retirement Study is a nationally-representative population-based prospective cohort of adults aged 51 or older. In 2000, participants were interviewed about physician-diagnosed chronic conditions, from which their multimorbidity-weighted index (MWI) was computed. Between 2000-2011, participants reported their current physical functioning using a modified Short Form-36. With MWI as a time-varying exposure, we jointly modeled its associations with physical functioning and survival.
Results: The final sample included 74,037 observations from 18,174 participants. At baseline, participants had a weighted mean MWI of 4.64.2 (range 0-36.8). During follow-up, physical functioning declined -1.72 (95% CI: -1.77, -1.67, p<0.001) HRS physical functioning units per point MWI in adjusted models. Over follow-up, 6,362 (34%) participants died. Mortality risk increased 8% (HR 1.08, 95% CI 1.07-1.08, p<0.001) per point MWI in adjusted models. Across all population subgroups, MWI was associated with greater physical functioning decline and mortality risk.
Conclusions: Multimorbidity and its associated decline in physical functioning were significantly associated with increased mortality. These associations can be predicted with an easily interpreted and applied multimorbidity index that can better identify and target adults at increased risk for disability and death.
|User Guide Notes|
|Alternate Journal||J. Gerontol. A Biol. Sci. Med. Sci.|
|PubMed Central ID||PMC6599282|
|Grant List||P30 AG053760 / AG / NIA NIH HHS / United States |
U01 AG009740 / AG / NIA NIH HHS / United States
P30 AG024824 / AG / NIA NIH HHS / United States
P60 AG008808 / AG / NIA NIH HHS / United States
K23 AG056638 / AG / NIA NIH HHS / United States