One in three older people who have difficulty reading and understanding basic health-related information may be at increased risk of death, concludes a UCL study published by the BMJ today.
The findings have important implications given rising levels of long term conditions and the UK government's plans for patients to become responsible and active partners in their care.
'Health literacy' is a measure of whether someone is able to apply reading skills and basic knowledge in a health context. Low-health literacy is associated with less knowledge of chronic diseases, poorer mental and physical health, limited use of preventive services, and higher rates of admissions to hospital.
However, much of the existing research into health literacy has been conducted in the US and relatively little was known about the scale of the problem in older adults in England. The UCL team set out to investigate the relationship between health literacy and mortality in older adults in England, irrespective of known risk factors like age, socioeconomic position and pre-existing illness.
The study involved 7,857 adults aged 52 years and over who took part in the second wave (2004-5) of the English Longitudinal Study of Ageing (ELSA). Participants completed a test of functional health literacy, which assessed their understanding of the written instructions associated with taking an aspirin tablet. Deaths were monitored until October 2009.
One in three adults was unable to completely understand the medicine label instructions, indicating limited health literacy.
A total of 621 deaths occurred during follow up: 321 (6 per cent) in the high test score group, 143 (9 per cent) in the medium group and 157 (16 per cent) in the low group.
Adults with the lowest health literacy scores were more than twice as likely to die within five years as those with the highest scores. Differences in age, socioeconomic position, and general health at the start of the study accounted for less than half of the increased risk.
Even after adjusting for measures of cognitive (mental) function, low health literacy was still a significant predictor of mortality.
This study suggests that a third of older adults in England have difficulties reading and understanding basic health related written information. Those with the poorest understanding are at greatest risk of mortality, say the authors.
''This study is a reminder that providing information doesn't necessarily equate to understanding,'' says co-author Sophie Bostock, UCL Epidemiology & Public Health. ''The patients most vulnerable to adverse health outcomes are those least likely to understand written health information.
''The findings should remind all healthcare professionals to adopt effective communication techniques for patients with low health literacy. The design and delivery of health related services for older adults in England should be sensitive to the limited health literacy capabilities within this population.''
The study was funded by the National Institute on Aging and the lead researchers, Sophie Bostock and Professor Andrew Steptoe, are supported by the British Heart Foundation.