Low health numeracy is associated with higher disease activity in systemic lupus erythematosus

Objective Evidence suggests low health literacy is prevalent in the United States and associated with worse clinical outcomes, yet few studies have investigated health literacy in systemic lupus erythematosus (SLE). The objective of this study was to determine the prevalence of low health literacy and numeracy in lupus patients and to examine its association with disease characteristics. Methods Patients with SLE were recruited from an academic center clinic. Participants completed in-person assessments of health literacy (Rapid Estimate of Adult Literacy in Medicine, REALM) and numeracy (Numeracy Understanding in Medicine Instrument Shortened Version, S-NUMi). Clinical disease activity measures were obtained, including urine protein to creatinine ratio (UPC), Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and physician global assessment (PhGA) scores. Results Ninety-five SLE patients participated in the study; 13% had low health literacy and 73% had limited health numeracy. Patients with lower health literacy and numeracy were more likely to be Black, have Medicaid insurance, and earn income <$50 K annually. In linear regression models, patients with limited health numeracy had, on average, PhGA scores 0.31 points higher (95% CI: 0.02, 0.60) than patients with adequate numeracy, after adjusting for race and age. No clinical outcomes were associated with health literacy. Conclusion In this exploratory study, we found SLE patients with low numeracy had higher disease activity. Our findings indicate that lower health literacy and numeracy are more common among Black and socioeconomically disadvantaged patients. Additional research will be needed to investigate the impact of health literacy on other outcomes and racial disparities in SLE.

Effects of Cognitive Functioning and Education on Later-Life Health Numeracy

<b><i>Introduction:</i></b> Previous studies have shown an association between a high health numeracy and good cognitive functioning. <b><i>Objective:</i></b> To investigate the moderation effect of education on this relationship and which brain structures support health numeracy. <b><i>Methods:</i></b> We examined 70 healthy older persons (66% females; mean ± SD: age, 75.73 ± 4.52 years; education, 12.21 ± 2.94 years). The participants underwent a T1-weighted 3-T MRI and a neuropsychological assessment including a health numeracy task. Statistical parametric mapping was applied to identify focal changes in cortical thickness throughout the entire brain and to correlate image parameters with behavioral measures. <b><i>Results:</i></b> Executive functions and mental calculation emerged as predictors of health numeracy (<i>B</i> = 0.22, <i>p</i> &#x3c; 0.05, and <i>B</i> = 0.38, <i>p</i> &#x3c; 0.01). An interaction was found between education and executive functions (<i>B</i> = –0.16, <i>p</i> = 0.01) and between education and mental calculation (<i>B</i> = –0.11, <i>p</i> &#x3c; 0.05). Executive functions and mental calculation had an impact on health numeracy in participants with a low to intermediate edu­cation (≤12 years) but not in those with a higher education (&#x3e;12 years). Health numeracy scores were associated with cortical thickness in the right dorsomedial prefrontal cortex and the right superior temporal gyrus (<i>p</i> = 0.01). <b><i>Conclusions:</i></b> Older people with a higher education perform better in health numeracy tasks than those with a lower education. They have access to previously acquired knowledge about ratio concepts and do not need to rely on executive functions and computational skills. This is highly relevant when decisions about health care have to be made.