Publications

Low socioeconomic status (SES) is associated with increased risk for adverse health outcomes; those with low SES are thought to experience greater environmental disadvantage and exposure to chronic stress over the life course. The effects of chronic stress on health have been measured by cortisol levels and variations in their diurnal pattern. However, the patterns of association between SES and cortisol have been equivocal in older adults. This paper examined in 98 older adults participating in the Brain Health Substudy of the Baltimore Experience Corps Trial baseline patterns of diurnal variation in salivary cortisol associated with lower versus higher SES using total income and perceived SES relative to others. For each measure, participants stratified into lower versus higher SES showed a more blunted rate of decline in diurnal salivary cortisol over the day in adjusted models (P values ≤ 0.05). There were no SES-related differences in awakening cortisol, cortisol-awakening response, or area under the curve. These findings confirm prior evidence of a biologic pathway through which socioeconomic disadvantage is linked to biologic vulnerability, and through which the impact of volunteer service in Experience Corps may be measured.

To develop a practical informant-based screening tool that reliably identifies patients with mild cognitive impairment (MCI) and dementia, we analyzed data from a sample of patients and normal controls seen in a memory clinic. All patients were evaluated with the Clinical Dementia Rating scale. Individual Clinical Dementia Rating responses were dichotomized and entered into a forward stepwise multivariable logistic regression model. Four independent predictors of MCI and dementia thus identified were combined into a prediction rule that was validated in a separate cohort drawn from the same clinic. Using a cut point of 2 or more positive responses to the 4 questions, the final prediction rule had sensitivity of 95% (95% confidence interval (CI): 92-97%) for MCI or dementia, and a specificity of 91% (95% CI: 86-95%). When applied to the validation cohort, the sensitivity for MCI or dementia was 96% (95% CI: 94-98%), and the specificity was 96% (95% CI: 92-98%). Using both cohorts, the positive likelihood ratio for MCI or dementia was 15.6 (95% CI: 14.0-17.3) and the negative likelihood ratio was 0.05 (95% CI: 0.04-0.07). This tool has the potential to identify patients who warrant further cognitive evaluation in busy outpatient or emergency department settings.