Publications

While the number of success stories for mapping genes associated with complex diseases using genome-wide association approaches is growing, there is still much work to be done in developing methods for such studies when the samples are collected from a population, which may not be homogeneous. Here we report the first genome-wide association study to identify genes associated with asthma in an admixed population. We genotyped 96 Puerto Rican moderate to severe asthma cases and 88 controls as well as 109 samples representing Puerto Rico's founding populations using the Affymetrix GeneChip Human Mapping 100K array sets. The data from samples representing Puerto Rico's founding populations was used to identify ancestry informative markers for admixture mapping analyses. In addition, a genome-wide association analysis using logistic regression was performed on the data. Although neither admixture mapping nor regression analysis gave any significant association with asthma after correction for multiple testing, an overlap analysis using the top scoring SNPs from different methods suggested chromosomal regions 5q23.3 and 13q13.3 as potential regions harboring genes for asthma in Puerto Ricans. The validation analysis of these two regions in 284 Puerto Rican asthma trios gave significant association for the 5q23.3 region. Our results provide strong evidence that the previously linked 5q23 region is associated with asthma in Puerto Ricans. The detection of causative variants in this region will require fine mapping and functional validation.

OBJECTIVES

To assess engagement in multiple steps of the advance care planning (ACP) process 6 months after exposure to an advance directive. In this study, ACP is conceptualized similarly to the behavior change model.

DESIGN

Descriptive study.

SETTINGS

County general medicine clinic in San Francisco.

PARTICIPANTS

One hundred seventy-three English or Spanish speakers, aged 50 and older (mean 61) given a standard (12th-grade reading level) and an easy-to-read (5th-grade reading level) advance directive.

MEASUREMENTS

Six months after exposure to two advance directives, self-reported ACP contemplation; discussions with family, friends discussions with clinicians; and documentation were measured. Associations were examined between ACP steps and between subject characteristics ACP engagement.

RESULTS

Most participants (73%) were nonwhite and 31% had less than a high school education. Sixty-one percent contemplated ACP, 56% discussed ACP with family or friends, 22% discussed ACP with clinicians, and 13% documented ACP wishes. Subjects who had discussed ACP with their family or friends were more likely to discuss ACP with their clinicians (36% vs 2%, P<.001) and document ACP wishes (18% vs 4%, P=.009) than those who had not. Latinos and subjects with less than a high school education discussed ACP more often with family or friends (P<.06) and clinicians (P<.03) than other ethnic groups and subjects with more education.

CONCLUSIONS

ACP involves distinct steps including contemplation, discussions, and documentation. The ACP paradigm should be broadened to include contemplation and discussions. Promoting discussions with family and friends may be one of the most important targets for ACP interventions, and literacy- and language-appropriate advance directives may help reverse patterns of sociodemographic disparities in ACP.