One in three older people who have difficulty reading and understanding basic health related information may be at increased risk of death, concludes a study published in the British Medical Journal 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.
Poor literacy skills are already associated with a wide range of adverse health outcomes. Much of the existing research into health literacy (being able to apply reading skills and basic knowledge in a health context) has been conducted in the US. 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, the scale of literacy problems in older adults in England is not known.
So a team of researchers at University College London 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 understanding of written instructions for taking an aspirin tablet. Deaths were monitored until October 2009.
A total of 621 deaths occurred during follow up: 321 (6%) in the high test score group, 143 (9%) in the medium group and 157 (16%) in the low group.
One in three adults was unable to completely understand the medicine label instructions, indicating limited health literacy.
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.
The findings should remind all healthcare professionals to adopt effective communication techniques for patients with low health literacy, they conclude. At a broader level, 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."