Biomarkers for progressive multifocal leukoencephalopathy: emerging data for use of JC virus DNA copy number in clinical trials.

Progressive multifocal leukoencephalopathy is a rare but devastating demyelinating disease caused by the JC virus (JCV), for which no therapeutics are approved. To make progress towards addressing this unmet medical need, innovations in clinical trial design are needed. Quantitative JCV DNA in CSF has the potential to serve as a valuable biomarker of progressive multifocal leukoencephalopathy disease and treatment response in clinical trials to expedite therapeutic development, as do neuroimaging and other fluid biomarkers such as neurofilament light chain. Specifically, JCV DNA in CSF could be used in clinical trials as an entry criterion, stratification factor, or predictor of clinical outcomes. Insights from the investigation of candidate biomarkers for progressive multifocal leukoencephalopathy might inform approaches to biomarker development for other rare diseases.

The Role of Marital Status in Physical Activity Among African American and White Men.

Racial differences in physical activity among men are well documented; however, little is known about the impact of marital status on this relationship. Data from the National Health and Examination Survey (NHANES) 1999-2006 was used to determine whether the association of race and physical activity among men varied by marital status. Marital status was divided into two categories: married and unmarried. Physical activity was determined by the number of minutes per week a respondent engaged in household/yard work, moderate and vigorous activity, or transportation (bicycling and walking) over the past 30 days. The sample included 7,131 African American (29%) and White(71%) men aged 18 years and older. All models were estimated using logistic regression. Because the interaction term of race and marital status was statistically significant (p < .001), the relationship between race, physical activity, and marital status was examined using a variable that reflects the different levels of the interaction term. After adjusting for age, income, education, weight status, smoking status, and self-rated health, African American married men had lower odds (odds ratio = 0.53, 95% confidence interval = [0.46-0.61], p < .001) of meeting federal physical activity guidelines compared with White married men. Possible dissimilarities in financial and social responsibilities may contribute to the racial differences observed in physical activity among African American and White married men.