Association between low functional health literacy and mortality in older adults: longitudinal cohort studyBMJ 2012; 344 doi: https://doi.org/10.1136/bmj.e1602 (Published 15 March 2012) Cite this as: BMJ 2012;344:e1602
- Sophie Bostock, research associate,
- Andrew Steptoe, professor of psychology
- Correspondence to: S Bostock
- Accepted 1 February 2012
Objective To investigate the association between low functional health literacy (ability to read and understand basic health related information) and mortality in older adults.
Design Population based longitudinal cohort study based on a stratified random sample of households.
Participants 7857 adults aged 52 or more who participated in the second wave (2004-5) of the English Longitudinal Study of Ageing and survived more than 12 months after interview. Participants completed a brief four item test of functional health literacy, which assessed understanding of written instructions for taking an aspirin tablet.
Main outcome measure Time to death, based on all cause mortality through October 2009.
Results Health literacy was categorised as high (maximum score, 67.2%), medium (one error, 20.3%), or low (more than one error, 12.5%). During follow-up (mean 5.3 years) 621 deaths occurred: 321 (6.1%) in the high health literacy category, 143 (9.0%) in the medium category, and 157 (16.0%) in the low category. After adjusting for personal characteristics, socioeconomic position, baseline health, and health behaviours, the hazard ratio for all cause mortality for participants with low health literacy was 1.40 (95% confidence interval 1.15 to 1.72) and with medium health literacy was 1.15 (0.94 to 1.41) compared with participants with high health literacy. Further adjustment for cognitive ability reduced the hazard ratio for low health literacy to 1.26 (1.02 to 1.55).
Conclusions A third of older adults in England have difficulties reading and understanding basic health related written information. Poorer understanding is associated with higher mortality. The limited health literacy capabilities within this population have implications for the design and delivery of health related services for older adults in England.
Contributors: SB did the statistical analysis, wrote the first draft of the manuscript, and is the guarantor. Both authors designed the study; analysed and interpreted the data; drafted and critically revised the manuscript for important intellectual content; and approved the final version.
Funding: The English Longitudinal Study of Ageing was developed by a team of researchers based at the University College London, National Centre for Social Research, and the Institute for Fiscal Studies. The data were collected by the National Centre for Social Research. The funding is provided by the National Institute of Aging in the United States, and a consortium of UK government departments coordinated by the Office for National Statistics. The developers and funders of the English Longitudinal Study of Ageing and the UK Data Archive do not bear any responsibility for the analyses or interpretations presented here. SB is supported by a PhD Studentship from the British Heart Foundation. AS holds the British Heart Foundation chair of psychology.
Competing interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
Ethical approval: The English Longitudinal Study of Ageing was approved by the London Multicentre Research Ethics Committee (MREC/01/2/91) and informed consent was obtained from all participants.
Data sharing: Users registered with the Economic and Social Data Service (ESDS) have access to the English Longitudinal Study of Ageing datasets, available at www.esds.ac.uk.
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