Sacramento Area Latino Study On Aging Research Articles

Metabolic dysfunction modifies the influence of traffic-related air pollution and noise exposure on late-life dementia and cognitive impairment: A cohort study of older Mexican-Americans.

For 1,612 elderly Mexican-American participants of the Sacramento Area Latino Study on Aging (SALSA) followed for up to 10 years, we estimated residential-based local traffic-related exposures relying on the California Line Source Dispersion Model version 4 (CALINE4) for nitrogen oxides (NOx) and the SoundPLAN software package (Version 8.0; NAVCON, Fullerton, CA) that implements the Federal Highway Administration Traffic Noise Model (TNM) for noise, respectively. We used Cox proportional hazard models to estimate the joint effects of NOx or noise exposures and obesity, hyperglycemia, or low high-density lipoprotein (HDL) cholesterol. The risk of developing dementia/CIND among participants with hyperglycemia who also were exposed to high levels of NOx (≥3.44 parts per billion [ppb] [75th percentile]) or noise (≥65 dB) was 2.4 (1.4, 4.0) and 2.2 (1.7, 3.9), respectively. For participants with low HDL-cholesterol, the estimated hazard ratios for dementia/CIND were 2.5 (1.4, 4.3) and 1.8 (1.0, 3.0) for those also exposed to high levels of NOx (≥3.44 ppb) or noise (≥65 dB), respectively, compared with those without metabolic dysfunction exposed to low traffic-related air pollution or noise levels. Exposure to traffic-related air pollution or noise most strongly increases the risk of dementia/CIND among older Mexican-Americans living in California who also exhibit hyperglycemia or low HDL-cholesterol.

Traffic-related Noise Exposure and Late-life Dementia and Cognitive Impairment in Mexican-Americans.

Recently, it has been suggested that environmental exposures from traffic sources including noise may play a role in cognitive impairment in the elderly. The objective of the study was to investigate the association between local traffic-related noise pollution and incident dementia or cognitive impairment without dementia (CIND) during a 10-year follow-up period. 1612 Mexican-American participants from the Sacramento Area Latino Study on Aging (SALSA) were followed every 12-15 months via home visits from 1998 to 2007. We used the SoundPLAN software package to estimate noise originating from local traffic with the input of Annual Average Daily Traffic (AADT) data from Metropolitan Planning Organizations (MPO) based on geocoded residential addresses at baseline (1998-1999). We estimated the risks of incident dementia or CIND from 24-hour and nighttime noise exposure using Cox proportional hazard models. During the follow-up, we identified 159 incident dementia or CIND cases in total. Per 11.6 dB (interquartile range width) increase in 24-hour noise, the hazard of developing dementia or CIND increased (hazard ratio = 1.3 [1.0, 1.6]) during follow-up; estimates were slightly lower (hazard ratio = 1.2 [0.97, 1.6]) when adjusting for modeled local air pollution exposure from traffic sources. Overall, the risk of dementia/CIND was elevated when 24-hour and nighttime noise were higher than 75 and 65 dB respectively. See video Abstract: http://links.lww.com/EDE/B728. In our study, traffic-related noise exposure was associated with increased risk of dementia or CIND in elderly Mexican-Americans. Future studies taking into account other noise sources and occupational noise exposure before retirement are needed.

Nativity, Neighborhoods, and Body Composition in the Sacramento Area Latino Study on Aging.

Globally, obesity influences the risk of many major chronic diseases. Our study examines the association between individual nativity and neighborhood level concentration of immigrants with 10-year changes in weight, body mass index (BMI), and waist circumference (WC) among older Latinos. The Sacramento Area Latino Study on Aging (SALSA) is a population-based prospective study of community-dwelling older adults of Mexican origin (baseline ages 58-101 years). The primary outcome was repeated measures of weight over a 10-year period for 1,628 respondents. Nativity was defined by participants' reported place of birth (US-born or Latin American foreign born). Neighborhood immigrant concentration was measured as the percentage of foreign born at census tract level (2000 US Census). We used linear mixed models with repeated measures of weight, height, BMI, and WC as dependent variables (level 1), clustered within individuals (level 2) and neighborhood migrant concentration (level 3). Foreign born (FB) respondents had lower baseline weight than the US-born (mean, 160 vs. 171 lbs, p < .0001). Over time, weight differences between the FB and the US-born decreased by 1.7 lbs/5 years as US-born weight decreased more rapidly. We observed a significant interaction between individual nativity and neighborhood immigrant concentration (p = .012). We found similar patterns for BMI, but did not find statistically significant differences in WC trajectories. Our study observed significant differences by foreign born vs. US nativity in baseline weight/BMI and in their trajectories over time. Additionally, we found weight/BMI differences in neighborhood immigrant concentration for the FB, but not for the US-born.

Air pollution, noise exposure, and metabolic syndrome – A cohort study in elderly Mexican-Americans in Sacramento area

BackgroundPrevious studies suggested that air pollutants may increase the incidence of metabolic syndrome, but the potential impact from traffic sources is not well-understood. This study aimed to investigate associations between traffic-related nitrogen oxides (NOx) or noise pollution and risk of incident metabolic syndrome and its components in an elderly Mexican-American population. MethodsA total of 1,554 Mexican-American participants of the Sacramento Area Latino Study on Aging (SALSA) cohort were followed from 1998 to 2007. We used anthropometric measures and biomarkers to define metabolic syndrome according to the recommendations of the Third Adult Treatment Panel of the National Cholesterol Education Program (NCEP ATP III). Based on participants’ residential addresses at baseline, estimates of local traffic-related NOx were generated using the California Line Source Dispersion Model version 4 (CALINE4), and of noise employing the SoundPLAN software package. We used Cox regression models with calendar time as the underlying time scale to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations of air pollution or noise with metabolic syndrome or its components. ResultsEach per unit increase of traffic-related NOx (2.29 parts per billion (ppb)) was associated with a 15% (HR = 1.15, 95% CI: 1.04–1.28) lower level of high-density lipoprotein cholesterol (HDL-cholesterol), and each 11.6 decibels (dB) increase in noise increased the risk of developing metabolic syndrome by 17% (HR = 1.17, 95% CI: 1.01–1.35). ConclusionPolicies aiming to reduce traffic-related air pollution and noise might mitigate the risk of metabolic syndrome and its components in vulnerable populations.

Allostatic Load, Unhealthy Behaviors, and Depressive Symptoms by Birthplace Among Older Adults in the Sacramento Area Latino Study on Aging (SALSA).

Objective: To assess whether unhealthy behaviors moderated the relationship between allostatic load (AL) and future significant depressive symptoms (SDSs) among 1,789 older Latinos. Method: Longitudinal data included baseline AL, three unhealthy behaviors (UBs), and 2-year follow-up SDS. Multivariable logistic regression analyses, stratified by birthplace (U.S. vs. foreign born), modeled the effects of AL, UB count (range = 0-3), and their interaction on follow-up SDS. Results: Compared with U.S.-born, foreign-born participants engaged in fewer UBs (0.52 vs. 0.60 behaviors, p = .01) and had higher baseline SDS (31% vs. 20%, p < .001). Among foreign-born participants, the effect of AL on future SDS (adjusted odds ratios [aORs]; 95% confidence interval [CI]) significantly increased across UB counts of 0 to 3: 1.06 [0.83, 1.35], 1.46 [1.14, 1.87], 2.00 [1.18, 3.41], and 2.75 [1.18, 6.44], respectively. Discussion: Among foreign-born Latinos, these results were most pronounced for women and adults above age 80, which may represent higher risk groups requiring more intensive screening for depression.

Association of metformin, sulfonylurea and insulin use with brain structure and function and risk of dementia and Alzheimer's disease: Pooled analysis from 5 cohorts.

ObjectiveTo determine whether classes of diabetes medications are associated with cognitive health and dementia risk, above and beyond their glycemic control properties.Research design and methodsFindings were pooled from 5 population-based cohorts: the Framingham Heart Study, the Rotterdam Study, the Atherosclerosis Risk in Communities (ARIC) Study, the Aging Gene-Environment Susceptibility-Reykjavik Study (AGES) and the Sacramento Area Latino Study on Aging (SALSA). Differences between users and non-users of insulin, metformin and sulfonylurea were assessed in each cohort for cognitive and brain MRI measures using linear regression models, and cognitive decline and dementia/AD risk using mixed effect models and Cox regression analyses, respectively. Findings were then pooled using meta-analytic techniques, including 3,590 individuals with diabetes for the prospective analysis.ResultsAfter adjusting for potential confounders including indices of glycemic control, insulin use was associated with increased risk of new-onset dementia (pooled HR (95% CI) = 1.58 (1.18, 2.12);p = 0.002) and with a greater decline in global cognitive function (β = -0.014±0.007;p = 0.045). The associations with incident dementia remained similar after further adjustment for renal function and excluding persons with diabetes whose treatment was life-style change only. Insulin use was not related to cognitive function nor to brain MRI measures. No significant associations were found between metformin or sulfonylurea use and outcomes of brain function and structure. There was no evidence of significant between-study heterogeneity.ConclusionsDespite its advantages in controlling glycemic dysregulation and preventing complications, insulin treatment may be associated with increased adverse cognitive outcomes possibly due to a greater risk of hypoglycemia.

Association of Positive Affect with Cognitive Health and Decline for Elder Mexican Americans.

The goal of this study was to investigate the linkages of positive affect (PA) with cognitive health and its decline among elder Mexican Americans. We conducted secondary analysis of longitudinal data from the Sacramento Area Latino Study on Aging (SALSA). We used the structural equation modeling framework to achieve three specific aims: (1) identify a valid measure of PA, (2) describe within-person trajectories of PA and cognitive health, and (3) test the inter-relations of these two processes over time. Results showed that, on average, PA and cognitive ability (including verbal memory) decreased over time. Yet, there was significant variability in these patterns of change. Bivariate latent growth curve models showed significant correlations of baseline levels and rates of change of PA and cognitive ability even after controlling for age, education, sex, bilingualism, and depression. Results support the hypothesis that increases and decreases in PA tend to be related to increases and decreases in cognitive health at old age among Mexican Americans.

Cross-border ties, nativity, and inflammatory markers in a population-based prospective study of Latino adults

Even after migration, immigrants and their descendants may continue to have ties to family and friends who remain in places of origin. Recent research suggests that these cross-border social ties have implications for health, although this scholarship has been limited to self-reported outcomes. Using data from the Sacramento Area Latino Study on Aging (SALSA), we estimate associations between cross-border social ties and inflammatory biomarkers among Latino adults (n = 1786). We find that immigrants who maintained any cross-border connection to family and friends in Latin America had significantly lower levels of baseline interleukin-6 (IL-6) and C-reactive protein (CRP) compared to their US-born counterparts with no cross-border ties. These results held for values of CRP at five-year follow-up for men only. In contrast, US-born women with cross-border ties to family and friends in Latin America had both significantly higher levels of CRP and significantly lower levels of tumor necrosis factor-alpha (TNF-α) at five-year follow-up relative to their US-born counterparts with no cross-border ties. We find descriptively that men who have cross-border ties are also less likely to be socially isolated within local contexts. Considering place-of-origin social connections may contribute critical nuance to studies of immigrant health, including disparities in inflammatory markers that may serve as indicators of underlying chronic disease.

Association Between Immigration History and Inflammatory Marker Profiles Among Older Adult Mexican Americans

ABSTRACTForeign-born Hispanics have better cardiometabolic health upon arrival in the US than their US-born counterparts, yet this advantage diminishes as duration of residence in the US increases. Underlying mechanisms explaining this paradox have been understudied. Using data from the Sacramento Area Latino Study on Aging (SALSA), this study examined immigration history (immigrant generation and duration of US residence) in relation to biomarkers of inflammation (interleukin-6 (IL-6), soluble forms of type 1 and 2 receptors of tumor necrosis factor-alpha (sTNF-R1 and sTNF-R2), C-reactive protein (CRP), leptin, adiponectin) in a sample of 1,290 predominantly Mexican-origin immigrants. Second and ≥3rd generation immigrants had higher IL-6 and leptin levels than 1st generation immigrants living in the US for less than 15 years (2nd generation percent difference = 45.9; 95% CI: 24.7, 70.7 and 3rd generation percent difference = 41.8; 95% CI: 17.7, 70.4). CRP and sTNF-R1 levels were higher among ≥3rd generation immigrants than 1st generation immigrants with less than 15 years of US residency. Worse inflammatory profiles were observed among Mexican-origin immigrants with longer US immigration histories, independent of health, and behavioral factors. Additional research is warranted to understand the factors that shape trajectories of biological risk across generations of Hispanics.

Education, bilingualism, and cognitive trajectories: Sacramento Area Latino Aging Study (SALSA).

This study examined the influence of education, country where education occurred, and monolingual-bilingual (English/Spanish) language usage on late life cognitive trajectories in the Sacramento Area Latino Study on Aging (SALSA), an epidemiological study of health and cognition in Hispanics, mostly of Mexican origin, age 60 and over (N = 1,499). SALSA followed a large cohort of older Latinos for up to 7 assessment waves from 1998 to 2007. Global cognition was assessed by using the Modified Mini Mental State Examination, and the Spanish English Verbal Learning Test was used to measure episodic memory. Education, country of origin, and language usage patterns were collected at the baseline assessment and used as predictors of longitudinal trajectories of cognition. Parallel process mixed effects models were used to examine effects of education and language variables on baseline cognition and rate of cognitive decline. Mixed effects longitudinal models showed that education had strong effects on baseline global cognition and verbal memory but was not related to decline over up to 9 years of longitudinal follow-up. Differences in education effects between subgroups educated in Mexico and in the United States were minor. Monolingual-bilingual language usage was not related to cognitive decline, and bilinguals did not significantly differ from monolingual English speakers on baseline cognitive scores. Hypotheses that higher education and bilingualism protect against late life cognitive decline were not supported and education effects on late-life cognitive trajectories did not substantially differ across U.S.- and Mexico-educated groups. (PsycINFO Database Record

APOE-related risk of mild cognitive impairment and dementia for prevention trials: An analysis of four cohorts

BackgroundWith the onset of prevention trials for individuals at high risk for Alzheimer disease, there is increasing need for accurate risk prediction to inform study design and enrollment, but available risk estimates are limited. We developed risk estimates for the incidence of mild cognitive impairment (MCI) or dementia among cognitively unimpaired individuals by APOE-e4 dose for the genetic disclosure process of the Alzheimer’s Prevention Initiative Generation Study, a prevention trial in cognitively unimpaired APOE-e4/e4 homozygote individuals.Methods and findingsWe included cognitively unimpaired individuals aged 60–75 y, consistent with Generation Study eligibility criteria, from the National Alzheimer’s Coordinating Center (NACC) (n = 5,073, 158 APOE-e4/e4), the Rotterdam Study (n = 6,399, 156 APOE-e4/e4), the Framingham Heart Study (n = 4,078, 67 APOE-e4/e4), and the Sacramento Area Latino Study on Aging (SALSA) (n = 1,294, 11 APOE-e4/e4). We computed stratified cumulative incidence curves by age (60–64, 65–69, 70–75 y) and APOE-e4 dose, adjusting for the competing risk of mortality, and determined risk of MCI and/or dementia by genotype and baseline age. We also used subdistribution hazard regression to model relative hazard based on age, APOE genotype, sex, education, family history of dementia, vascular risk, subjective memory concerns, and baseline cognitive performance. The four cohorts varied considerably in age, education, ethnicity/race, and APOE-e4 allele frequency. Overall, cumulative incidence was uniformly higher in NACC than in the population-based cohorts. Among APOE-e4/e4 individuals, 5-y cumulative incidence was as follows: in the 60–64-y age stratum, it ranged from 0% to 5.88% in the three population-based cohorts versus 23.06% in NACC; in the 65–69-y age stratum, from 9.42% to 10.39% versus 34.62%; and in the 70–75-y age stratum, from 18.64% to 33.33% versus 38.34%. Five-year incidence of dementia was negligible except for APOE-e4/e4 individuals and those over 70 y. Lifetime incidence (to age 80–85 y) of MCI or dementia for the APOE-e4/e4 individuals in the long-term Framingham and Rotterdam cohorts was 34.69%–38.45% at age 60–64 y, 30.76%–40.26% at 65–69 y, and 33.3%–35.17% at 70–75 y. Confidence limits for these estimates are often wide, particularly for APOE-e4/e4 individuals and for the dementia outcome at 5 y. In regression models, APOE-e4 dose and age both consistently increased risk, as did lower education, subjective memory concerns, poorer baseline cognitive performance, and family history of dementia. We discuss several limitations of the study, including the small numbers of APOE-e4/e4 individuals, missing data and differential dropout, limited ethnic and racial diversity, and differences in definitions of exposure and outcome variables.ConclusionsEstimates of the absolute risk of MCI or dementia, particularly over short time intervals, are sensitive to sampling and a variety of methodological factors. Nonetheless, such estimates were fairly consistent across the population-based cohorts, and lower than those from a convenience cohort and those estimated in prior studies—with implications for informed consent and design for clinical trials targeting high-risk individuals.

The Impact of Neighborhood Socioeconomic Position on Prevalence of Diabetes and Prediabetes in Older Latinos: The Sacramento Area Latino Study on Aging.

Diabetes is a leading cause of morbidity and mortality in Latinos, but few studies of disease risk in this subpopulation examine both area-level socioeconomic position (SEP) and its association with individual-level risk factors. This study sought to examine the cross-sectional relationship between neighborhood socioeconomic position (NSEP) and prevalent diabetes and prediabetes status among older Latinos. Longitudinal health data were collected from 1,789 participants in the Sacramento Area Latino Study on Aging (SALSA). Among SALSA participants, higher NSEP was associated with lower diabetes prevalence (p = .001). Adjustment for body mass index and other individual-level factors did not affect this relationship. No association was observed between NSEP and prediabetes in both unadjusted and adjusted models. Neighborhoods with higher SEP had a lower prevalence of diabetes. This study highlights the importance of considering neighborhood factors that may place older Latinos at high risk for this disease.

Development and validation of a brief dementia risk assessment tool for use in primary care

Undiagnosed dementia is common in older adults, and detection of 'any cognitive impairment' is now federally mandated as part of the Medicare Annual Wellness Visit. Yet screening all older adults for cognitive impairment may result in unacceptably high false positive rates, particularly in younger Medicare patients. The objective of our study was to develop and validate a brief Dementia Risk Assessment (DRA) tool for use in primary care to enable clinicians to identify high-risk patients who should be targeted for cognitive screening. The DRA was developed and validated using data from four existing cohort studies: the Cardiovascular Health Study (CHS), Framingham Heart Study (FHS), Health and Retirement Study (HRS), and Sacramento Area Latino Study on Aging (SALSA). These studies were selected because they included data on incident dementia and a broad palette of potential risk markers and together provided representation of individuals from diverse geographic and race/ethnic backgrounds. We first calculated 6-year dementia risk as a function of age and set ≥80 years as the age at which cognitive screening should be considered based on age alone. In participants age 65–79 years, we then performed Cox proportional hazards analyses and used an iterative process to identify a common set of dementia risk predictors. Meta-analysis was performed to develop a DRA point score based on the predictors retained in the final model. The final DRA tool included age (1 point/year), <12 years education (9 points), stroke (6 points), diabetes mellitus (3 points), body mass index <18.5 kg/m 2 (8 points), requiring assistance with money or medications (10 points), and evidence of depression (anti-depressant use or self-reporting “everything an effort” ≥3 days/week, 6 points). Accuracy based on Harrell's c statistic (95% confidence interval) was CHS, 0.68 (0.65, 0.72); FHS, 0.77 (0.73, 0.82); HRS, 0.76 (0.74, 0.77); and SALSA, 0.78 (0.72, 0.83). Across all 4 studies, a point-value of ≥22 identified a group of 65–79 year-olds whose 6-year dementia risk was comparable to 80–84 year-olds. The DRA is a simple tool that can be used in primary care to identify older patients with an increased risk of developing dementia who should be considered for cognitive screening.

Reduced heart rate variability is associated with worse cognitive function in elderly Mexican-Americans

Heart rate variability (HRV) is a subclinical measure of central autonomic function. Reduced HRV has been found to be a strong predictor of cardiovascular risk factors, cardiovascular events and mortality. Therefore, reduced HRV may be associated with cognitive neurodegeneration. Yet this has been relatively unexplored, particularly in minority populations. We investigated whether autonomic nervous system dysfunction, measured as reduced heart rate variability, was associated with worse cognitive function in elderly Mexican Americans. The Sacramento Area Latino Study on Aging (SALSA) is a prospective cohort study of 1,789 community-dwelling Mexican-Americans aged 60–101 years at baseline in 1998–1999. SALSA includes seven annual study visits. HRV was measured in a total of 869 subjects who participated in either visit 5 or 6 and thus constituted our analytical sample. HRV was assessed using the ANS2000 which is an ECG monitor and respiration pacer measuring variability in heart rate in response to deep breathing. Cognitive function was assessed using the Modified Mini Mental State Exam (3MS), a 100-point test of global cognitive function. For ease of interpretation, we categorized HRV into quartiles (Q1 to Q4: reduced to high HRV). We fit linear regression models to estimate the associations between quartile of HRV and cognitive function (3MS). Our sample of 869 participants had a mean age of 75 years (SD=6.1) and included 59% females. A total of 14% of the participants reported having had a stroke, 41% had type-2 diabetes, and more than 90% had hypertension. Reduced HRV was associated with older age, lower education, having had a stroke, a diagnosis of type-2 diabetes, hypertension, and elevated depressive symptoms. In models adjusted for age, gender, education, diabetes, stroke, and depressive symptoms, compared to subjects in the highest quartile of HRV, those in quartile 1 had a 4-point lower mean 3MS score (p<0.01), those in quartile 2 had a 2-point lower mean 3MS score (p=0.04), and those in quartile 3 had a 1-point lower mean 3MS score (p=0.35). Reduced HRV is associated with worse performance on the test of global cognitive function, above and beyond traditional cardiovascular risk factors.

Abstract 175: Stroke and 10-year Risk of Dementia and Cognitive Impairment Among Older Mexican Americans

Background: Stroke is a leading cause of death in the United States and has been linked to an increased risk of dementia and cognitive impairment. The prevalence of stroke and vascular risk factors are higher among Mexican Americans than non-Hispanic whites, but the literature on stroke and dementia and cognitive impairment among this growing ethnic group remains largely unexplored. Objective: We evaluated the association between non-fatal stroke and incidence of dementia/cognitive impairment without dementia (CIND) in a cohort of older Mexican Americans, accounting for the competing risk of mortality. Methods: The present study included 1,617 participants from the Sacramento Area Latino Study on Aging (SALSA), a population-based study of Mexican Americans aged 60-98 years, who were free of dementia/CIND at baseline in 1998-1999 and followed through 2007. At annual study visits, stroke events were identified by self-report of a physician diagnosis or hospitalization and dementia and CIND cases were identified with a three-phase clinical assessment protocol. We evaluated the association between baseline and time dependent stroke and incidence of dementia/CIND with Fine and Gray competing risk regression models to account for the competing risk of mortality. Results: There were 221 participants with a history of stroke at baseline or who experienced a non-fatal stroke during the study. Over a mean follow-up of 6.5 years, there were 159 incident dementia/CIND cases and 298 deaths (n=61 deaths due to stroke). After accounting for the competing risk of mortality and adjusting for sex, education, waist circumference, diabetes, and systolic blood pressure, individuals with a stroke event had a three-fold increased risk of dementia/CIND compared to those with no stroke event (hazard ratio=2.97, 95% CI: 2.05-4.30). Conclusions: These results suggest that among older Mexican Americans, stroke is strongly associated with incidence of dementia/CIND, even after accounting for traditional vascular risk factors and the competing risk of mortality.

Impact of Gender and Blood Pressure on Poststroke Cognitive Decline among Older Latinos

Poststroke cognitive decline (PSCD) is an important consequence of stroke that may be more severe in women than in men. The existence of any gender differences in PSCD among Mexican Americans, and their potential mechanisms, such as blood pressure (BP), remain unknown. We assessed PSCD stratified on gender in older Mexican Americans and explored the influence of pre- and poststroke systolic BP on PSCD. Among 1576 nondemented, stroke-free adults 60 years of age or older when recruited between 1998 and 1999 in the Sacramento Area Latino Study on Aging (SALSA) cohort, we examined pre- and poststroke longitudinal changes in Spanish English Verbal Learning test scores (WL), a verbal memory test, and errors on the Modified Mini Mental State Examination (3MSE) scores, a global cognition test, stratified by gender, adjusting for baseline and time-varying covariates with linear mixed effects models. We identified 151 adults (mean age 72 ± 8 years) with incident first-ever stroke during 10 years of follow-up. After adjustment for age, education, and time-varying depressive symptoms, 3MSE errors increased by 22% per year (95% confidence interval [CI] 6.8-36.7%) in men and 13.2% per year (95% CI 3.5-22.9%) in women over the poststroke period. Poststroke WL scores improved by 0.05 words per year (95% CI -0.24 to 0.33) in men and by 0.09 words per year (95% CI -0.16 to 0.34) in women. Results persisted after adjustment for time-varying systolic BP. Among this population of older Mexican Americans, PSCD did not differ by gender. We found no evidence that systolic BP influenced PSCD in women or men.

Abstract 047: Impact of Acculturation on Framingham Cardiovascular Risk Factors Among Elderly Mexican Americans

Background: Acculturation is the process by which immigrant groups adopt the cultural practices and values of the host country. Higher levels of acculturation among Latinos have been shown to be associated with a higher prevalence of traditional CVD Framingham risk factors (FRFs) in some studies. The association of acculturation and prevalence of traditional CVD risk factors in elderly Latinos is less well established. Hypothesis: Higher acculturation is associated with higher CVD FRFs prevalence. Methods: We evaluated the association of acculturation with prevalence of FRF among 1,789 elderly men and women from the Sacramento Area Latino Study on Aging (SALSA) using multivariate linear and logistic regression. SALSA is a well-characterized, NIH funded cohort study of Mexican Americans aged &gt; 60 followed since 1998–1999. Acculturation was measured using the validated bidimensional Acculturation Rating Scale for Mexican Americans-II and modeled as a continuous variable per interquantile range increase (IQR). We adjusted for age, gender, nativity status, income, insurance and the use of antihyperglycemic and antihypertensive medications. To evaluate whether differences in behavior may mediate the association of acculturation and FRFs we further adjusted for social and behavioral factors (marital status, physical activity, smoking, alcohol). We tested for the interaction of acculturation with FRF by nativity status. Results: Median age was 69.8 ± 7.1 and the overall IQR was 24 points. The mean acculturation score for US born Mexican Americans was 30.7 ±9.9 compared to 13.5 ± 9.4 for foreign born (p&lt;0.001). Higher acculturation was associated with lower SBP (beta −1.79, 95%CI [−3.55, −0.02] per IQR increase in acculturation score) and lower LDL (beta −3.59, 95% CI [−6.79, −0.39] per IQR increase in acculturation score) after age and sex adjustment. Acculturation was not associated with total cholesterol, HDL, DM, BMI or smoking (all p values &gt;0.05). The association of acculturation and SBP was attenuated after adjustment (beta −0.90, 95% CI [−2.99, 1.19] per IQR increase in acculturation score. Higher acculturation remained associated with lower LDL levels (β=−4.82, 95% CI [−8.7, −0.9] per IQR increase in acculturation score) after full adjustment. Stratification by nativity status did not affect these results. Conclusions: Contrary to other reports in middle-aged persons, higher levels of acculturation were associated with lower LDL and not higher prevalence of CVD FRFs in a large cohort of elderly Mexican Americans. The effect of acculturation in CVD risk factors may differ across the life course.

Abstract P148: C-Reactive Protein (CRP) and the Prediction of Cardiovascular Death Among Mexican-Americans

Background: Addition of C-reactive protein (CRP) improves risk stratification provided by traditional Framingham risk factors (FRFs) in some populations, but findings vary by gender and by race/ethnicity. Whether CRP levels can improve risk prediction of cardiovascular mortality (CVD) among elderly Hispanics is unknown. Hypothesis: CRP will add incremental CVD risk prediction in addition to FRFs. Methods: We evaluated whether addition of baseline CRP to the Framingham risk score can improve CVD risk stratification for CVD death among 1,422 participants (536 males, 886 females) from the Sacramento Area Latino Study on Aging (SALSA). SALSA is a well-characterized, NIH funded cohort study of Mexican Americans aged &gt; 60 followed since 1998–1999. Death was ascertained by participant contacts, obituary reviews and cause of death from death certificates. We evaluated the association of CRP levels with CVD death using Cox proportional hazards models adjusting for FRFs stratified by gender. We calculated gender stratified net reclassification improvement (NRI) in models with and without CRP to predict 10-year CVD risks using the established FRFs categories (&lt;5%, 5–10%, 10–20%, &gt; 20%). Results: Mean baseline age was 70.7 and mean CRP level was 5.86 ng/ml. There were 167 CVD male deaths (mortality rate 39.2 per 1,000 person years) and174 among women (mortality rate 27.8 per 1,000 person years). Higher CRP levels were significantly associated with higher CVD mortality risk in men, HR of 1.29 (95% CI 1.11 – 1.50) but not women, HR 0.94 (95% CI 0.81 – 1.08) after adjustment for covariates. Addition of CRP was useful in reclassifying CVD death risk among men defined by FRF alone, and this was due to correct reclassification of those who did not experience CVD death from the highest risk group to a lower risk category. The majority of male participants (619/745=83%) were classified as having &gt;20%risk in the model without CRP. Mortality rate for men initially classified as having &gt; 20% risk was 37.9 per 1,000 person years. After addition of CRP, 6% were reclassified into an intermediate risk category (NRI 7.4%, p&lt; 0.001) and their mortality rate was 10.3 per 1,000 person years. Overall, NRI for men was 4.2% (p=0.05). In contrast, addition of CRP among women was associated with increased misclassification to a higher risk category (NRI= − 13.4%, p=0.0001). Conclusion: A risk prediction model that includes CRP improves cardiovascular risk classification among elderly Mexican-American men but not women as defined by traditional FRFs.

Transcobalamin C776G genotype modifies the association between vitamin B12 and homocysteine in older Hispanics

BackgroundA common polymorphism, C776G, in the plasma B12 transport protein transcobalamin (TC), encodes for either proline or arginine at codon 259. This polymorphism may affect the affinity of TC for B12 and subsequent delivery of B12 to tissues.MethodsTC genotype and its associations with indicators of B12 status, including total B12, holotranscobalamin (holoTC), methylmalonic acid, and homocysteine, were evaluated in a cohort of elderly Latinos (N=554, age 60–93y) from the Sacramento Area Latino Study on Aging (SALSA).ResultsThe distribution of TC genotypes was 41.3% homozygous reference (776CC) and 11.6% homozygous variant (776GG). No differences between the homozygous genotypes were observed in total B12, holoTC, methylmalonic acid, or homocysteine. The holoTC/total B12 ratio was lower in the 776GG group compared with the 776CC group (p=0.04). Significant interactions of TC genotype with total B12 (p=0.04) and with holoTC (p≤0.03) were observed such that mean homocysteine concentrations and the odds ratios for hyperhomocysteinemia (>13 µmol/L) were higher in the 776CC subjects compared with all carriers of the G allele (776CG and 776GG combined) when total B12 (<156 pmol/L) or holoTC (<35 pmol/L) were low.ConclusionsThis population of older Latinos has a lower prevalence of the TC 776GG variant than reported for Caucasian populations. The association between vitamin B12 and homocysteine concentrations is modified by TC 776 genotype. It remains to be determined if the TC C776G polymorphism has a significant effect on the hematological and neurological manifestations of B12 deficiency or on vascular and other morbidities associated with hyperhomocysteinemia.

Persistent Infection, Inflammation, and Functional Impairment in Older Latinos

The objective of this study was to examine whether cytomegalovirus (CMV), herpes simplex virus type-1 (HSV-1), and C-reactive protein (CRP) are associated with functional impairment in older Latinos. A cross-sectional analysis of a cohort study was conducted with a community-dwelling elderly population. The sample was a subset (N = 1559/1789) of participants in the Sacramento Area Latino Study on Aging (SALSA) ages 60-101 with available serum samples and functional impairment measures. Baseline serum samples were assayed for levels of immunoglobulin G antibodies to CMV and HSV-1 and for levels of CRP. Several measures were used to assess functional impairment, including activities of daily living (ADL), instrumental activities of daily living (IADL), and walking pace. CMV and CRP showed statistically significant graded associations with ADL functional impairment, even after controlling for age and gender. The relationship between CMV and ADL was slightly attenuated, and the confidence interval contained the null value when adjusted for total number of health conditions, body mass index, and household income. Only high levels of CRP were significantly related to ADL and IADL impairment even after adjusting for all other covariates. Inflammation is clearly linked to physical functioning among aging Latinos. This study also suggests a role for CMV infection in relation to ADL impairment. Further research examining the influence of infection, immune response, and inflammation on longitudinal trajectories of physical functioning is warranted.