Dataset Information

Caregiving frequency and physical function: the Women's Health Initiative.

ABSTRACT:

Background

Informal caregiving is common for older women and can negatively affect health, but its impact on physical function remains unclear. Using inverse probability weighting methods, we quantified the association of caregiving with physical function over 6 years.

Methods

Study participants were 5,649 women aged 65 years and older at baseline of the Woman's Health Initiative Clinical Trial (multicenter recruitment, 1993-1998) with complete caregiving data and function at baseline and at least one follow-up. Caregiving was self-reported (low-frequency if ?2 times per week and high-frequency if ?3 times per week). Performance-based measures of physical function including timed walk (meters/second), grip strength (kilograms), and chair stands (number) were measured at baseline and years 1, 3, and 6. Associations and 95% confidence intervals of baseline caregiving with physical function were estimated by generalized estimating equations with inverse probability weighting by propensity and attrition scores, calculated by logistic regression of baseline health and demographic characteristics.

Results

Over follow-up, low-frequency caregivers had higher grip strength when compared with noncaregivers (mean difference = 0.63kg, confidence interval: 0.24, 1.01). There were no observed differences between high-frequency caregivers and noncaregivers on grip strength or for either caregiver group when compared with noncaregivers on walk speed or chair stands. Rates of change in physical function measures did not differ by caregiving status.

Conclusions

Caregiving was not associated with poorer physical function in this sample of older women. Low-frequency caregiving was associated with better grip strength at baseline which persisted through follow-up. This study supports the concept that informal caregiving may not have universally negative health consequences.

SUBMITTER: Rosso AL

PROVIDER: S-EPMC4311185 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Publications

Caregiving frequency and physical function: the Women's Health Initiative.

Rosso Andrea L AL Lee Brian K BK Stefanick Marcia L ML Kroenke Candyce H CH Coker Laura H LH Woods Nancy F NF Michael Yvonne L YL

The journals of gerontology. Series A, Biological sciences and medical sciences 20140724 2

<h4>Background</h4>Informal caregiving is common for older women and can negatively affect health, but its impact on physical function remains unclear. Using inverse probability weighting methods, we quantified the association of caregiving with physical function over 6 years.<h4>Methods</h4>Study participants were 5,649 women aged 65 years and older at baseline of the Woman's Health Initiative Clinical Trial (multicenter recruitment, 1993-1998) with complete caregiving data and function at base ...[more]

PMID: 25060315

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Project description:The dietary modification (DM) clinical trial, within the Women's Health Initiative (WHI), studied a low-fat dietary pattern intervention that included guidance to increase vegetables, fruit, and grains. This study was motivated in part from uncertainty about the reliability of observational studies examining the association between dietary fat and chronic disease risk by using self-reported dietary data. In addition to this large trial, which had breast and colorectal cancer as its primary outcomes, a substantial biomarker research effort was initiated midway in the WHI program to contribute to nutritional epidemiology research more broadly. Here we review and update findings from the DM trial and from the WHI nutritional biomarker studies and examine implications for future nutritional epidemiology research. The WHI included the randomized controlled DM trial (n = 48,835) and a prospective cohort observational (OS) study (n = 93,676), both among postmenopausal US women, aged 50-79 y when enrolled during 1993-1998. Also reviewed is a nutrition and physical activity assessment study in a subset of 450 OS participants (2007-2009) and a related controlled feeding study among 153 WHI participants (2010-2014). Long-term follow-up in the DM trial provides evidence for intervention-related reductions in breast cancer mortality, diabetes requiring insulin, and coronary artery disease in the subset of normotensive healthy women, without observed adverse effects or changes in all-cause mortality. Studies of intake biomarkers, and of biomarker-calibrated intake, suggest important associations of total energy intake and macronutrient dietary composition with the risk for major chronic diseases among postmenopausal women. Collectively these studies argue for a nutrition epidemiology research agenda that includes major efforts in nutritional biomarker development, and in the application of biomarkers combined with self-reported dietary data in disease association analyses. We expect such efforts to yield novel disease association findings and to inform disease prevention approaches for potential testing in dietary intervention trials. This trial was registered at clinicaltrials.gov as NCT00000611.

Dataset Information

Caregiving frequency and physical function: the Women's Health Initiative.

Background

Methods

Results

Conclusions

Publications

Caregiving frequency and physical function: the Women's Health Initiative.

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