PubMed Health⌕ Search

Biomedical subjects

Mary N Haan

Publications and source records attributed to Mary N Haan.

At least 19 recordsLinked to original sources

Hormone therapy and age-related macular degeneration: the Women's Health Initiative Sight Exam Study.

OBJECTIVE: To determine the effectiveness of treatment with conjugated equine estrogens (CEE) or with CEE combined with progestin (CEE + P) on age-related macular degeneration (AMD). METHODS: In an ancillary study to the Women's Health Initiative clinical trial of hormone therapy, 4262 women 65 years and older underwent fundus photography for the determination of AMD. Participants were recruited from April 2000 to June 2002 at 21 clinical sites an average of 5 years after randomization. Participants were randomized to treatment with CEE, CEE + P, or placebo. Participants had been treated for an average of 5 years at the ophthalmic evaluation for AMD. RESULTS: The overall prevalence of any AMD was 21.0%. No association was found between CEE + P (odds ratio [OR], 0.91; 95% confidence interval [CI], 0.75-1.11) or CEE alone (OR, 0.98; 95% CI, 0.78-1.25) and early-stage AMD. The CEE + P was associated with a reduced risk of soft drusen (OR, 0.83; 95% CI, 0.68-1.00) after adjustment for covariates and with a reduced risk of neovascular AMD (OR, 0.29; 95% CI, 0.09-0.92). CONCLUSIONS: Treatment with CEE alone or CEE + P does not affect early- or late-stage AMD. Treatment with CEE + P may reduce the risk of soft drusen or neovascular AMD.

Aged↗

Therapy Insight: type 2 diabetes mellitus and the risk of late-onset Alzheimer's disease.

A number of well-designed epidemiological studies have linked type 2 diabetes mellitus (T2DM) with an increased risk of Alzheimer's disease (AD). Several mechanisms could help to explain this proposed link, including insulin and insulin resistance, inflammatory cytokines, and oxidative stress. Obesity or physical inactivity might also influence AD through effects on hypertension, insulin sensitivity or inflammation. Typical AD pathology, such as amyloid-beta deposits, might be exacerbated by insulin dysregulation, T2DM itself, or microvascular disease that is a consequence of T2DM. T2DM patients are not routinely evaluated for cognitive outcomes, and cognitive impairment in T2DM is rarely treated. Similarly, AD patients are not routinely evaluated for T2DM or hyperinsulinemia. Current treatments for AD have only modest benefits, and several drugs that target metabolic and inflammatory pathways are being evaluated, most notably the statins, which reduce LDL and inflammation but might not influence amyloid- deposition, an important precursor for AD. Although some evidence supports a potentially important role for peroxisome proliferative activated receptor agonists such as glitazones, at present there are no published randomized clinical trials in AD patients of any drugs that target insulin or insulin resistance. Clinical implications of the T2DM-AD link include cognitive evaluations of patients with T2DM, and potential benefits for such patients through treatment with statins or diabetes drugs that target insulin.

Age of Onset↗

Antidepressant class and dosing among older Mexican Americans: application of geropsychiatric treatment guidelines.

OBJECTIVE: The objective of this study was to characterize patterns and correlates of antidepressant drugs (AD) among older Mexican Americans (MAs). METHODS: This study consisted of a cross-sectional, community-based sample from Northern California. AD class and dosing label information were inventoried and compared with Expert Consensus Guidelines for geriatric depression pharmacotherapy. RESULTS: Overall, 7.1% had been prescribed an AD, but 4.9% were within starting dose ranges. Fewer ADs (3.9%) were consistent with Consensus class and dose guidelines. Depressive symptoms and diabetes were significant positive predictors of ADs. Recent immigrants had lower odds of AD prescriptions. CONCLUSIONS: AD prescriptions among older MAs are low. Omitting AD class and dosing information may overestimate pharmacotherapy for geriatric depression.

Aged↗

Measurement of total vitamin B12 and holotranscobalamin, singly and in combination, in screening for metabolic vitamin B12 deficiency.

BACKGROUND: The standard screening test for vitamin B12 deficiency, measurement of total plasma vitamin B12, has limitations of sensitivity and specificity. Plasma vitamin B12 bound to transcobalamin (holoTC) is the fraction of total vitamin B12 available for tissue uptake and therefore has been proposed as a potentially useful alternative indicator of vitamin B12 status. METHODS: We compared the diagnostic accuracy of total vitamin B12, holoTC, and a combination of both measures to screen for metabolic vitamin B12 deficiency in an elderly cohort (age > or = 60 years). Plasma methylmalonic acid and homocysteine were used as indicators of vitamin B12 deficiency. RESULTS: Low total vitamin B12 (< 148 pmol/L) and low holoTC (< 35 pmol/L) were observed in 6.5% and 8.0%, and increased methylmalonic acid (> 350 nmol/L) and homocysteine (> 13 micromol/L) were observed in 12.1% and 17.0% of the study participants. In multiple regression models, holoTC explained 5%-6% more of the observed variance in methylmalonic acid and homocysteine than did total vitamin B12 (P < or = 0.004). ROC curve analysis indicated that total vitamin B12 and holoTC were essentially equivalent in their ability to discriminate persons with and without vitamin B12 deficiency. Individuals with low concentrations of both total vitamin B12 and holoTC had significantly higher concentrations of methylmalonic acid and homocysteine than did individuals with total vitamin B12 and/or holoTC within the reference intervals (P < 0.001). CONCLUSIONS: HoloTC and total vitamin B12 have equal diagnostic accuracy in screening for metabolic vitamin B12 deficiency. Measurement of both holoTC and total vitamin B12 provides a better screen for vitamin B12 deficiency than either assay alone.

Aged↗

Education, income, occupation, and the 34-year incidence (1965-99) of Type 2 diabetes in the Alameda County Study.

BACKGROUND: Lower socioeconomic position (SEP) is related to higher prevalence of Type 2 diabetes, yet little is known about the relationship of SEP with incident diabetes. METHODS: The association between SEP, measured by self-reported education, income, and occupation, and Type 2 diabetes incidence was examined in a community sample of 6147 diabetes-free adults from Alameda County, CA. Cox proportional hazards models estimated the effect of baseline (1965) and time-dependent (value changes over time) measures of SEP on incident diabetes over a 34-year study period (1965-99). Demographic confounders (age, gender, race, and marital status) and potential components of the causal pathway (physical inactivity, smoking, alcohol consumption, body composition, hypertension, depression, and health care access) were included as fixed or time-dependent covariates. RESULTS: Education, income, and occupation were associated with increased diabetes risk in unadjusted models. In baseline models adjusted for demographics, respondents with <12 years of education had 50% excess risk compared with those with more education [hazard ratio (HR) = 1.5, 95% confidence interval (95% CI) 1.11-2.04], but income and occupation were no longer significantly associated with increased risk. Further adjustment minimized the significance of all associations. Time-dependent effects were consistently elevated for low education and male blue-collar occupation, but non-significant after full adjustment (HR = 1.1, 95% CI 0.79-1.47 and HR = 1.3, 95% CI 0.91-1.89, respectively). CONCLUSIONS: Socioeconomic disadvantage, especially with low educational attainment, is a significant predictor of incident Type 2 diabetes, although associations were largely eliminated after covariate adjustment. Obesity and overweight appear to mediate these associations.

Adolescent↗

Comparing SF-36 scores across three groups of women with different health profiles.

BACKGROUND: The widespread use of the Medical Outcomes Study (MOS) 36-item Short-Form Health Survey (SF-36) facilitates the comparison of health-related quality of life (HRQL) across independent studies. OBJECTIVES: To compare the scores of eight scales and two summary scales of the SF-36 across participants in the Women's Healthy Eating and Living (WHEL) trial, the Women's Health Initiative-Dietary Modification trial (WHI-DM), and the MOS, and to illustrate the use of effect sizes for interpreting the importance of group differences. METHODS: WHEL and WHI-DM are both multi-center dietary interventions; only data from the UC Davis sites were used in our study. WHEL participants had a recent history of breast cancer, WHI-DM participants were healthy, postmenopausal women, and women in the MOS had a history of hypertension, diabetes, heart disease, or depression. General linear models were used to identify statistically significant differences in scale scores. Meaningful differences were determined by effect sizes computed using a common within-group standard deviation (SD) and SDs from normative data. RESULTS: After adjusting for age and marital status, SF-36 scores for the WHI-DM and WHEL samples were similar and both had statistically significantly higher scores than the MOS sample. Relative to the WHEL or WHI-DM studies, MOS scores for scales related to the physical domain were clearly meaningfully lower whereas scale scores related to the mental health domain were potentially meaningfully lower. CONCLUSIONS: The HRQL of breast cancer survivors is comparable to that of healthy women and better than that of women with chronic health conditions, particularly with respect to physical health. This study illustrated the use of ranges of effects sizes for aiding the interpretation of SF-36 scores differences across independent studies.

Activities of Daily Living↗

A semantic verbal fluency test for English- and Spanish-speaking older Mexican-Americans.

Currently, there are few semantic verbal fluency tests available with appropriate and adequate normative data for older Latinos of Mexican ancestry. The purposes of this study were to examine the effects of language and socioeconomic variables on a semantic verbal fluency test, derive normative data and develop statistical corrections for the effects of significant variables. A large, community-dwelling sample of Latinos of primarily Mexican ancestry over age 60 was asked to name animals with four legs within 1 min in their preferred language of English or Spanish. The total sum of animals named was influenced by age, education, gender, and, to a much lesser extent, language of test administration. Regression coefficients derived from demographic variables were used to adjust raw scores in a general correction formula, and specific percentile cutoff values were identified for these adjusted scores. Normative data tables stratified on demographic variables are also presented.

Aged↗

Spanish and English neuropsychological assessment scales: relationship to demographics, language, cognition, and independent function.

This study examined the relationship of the Spanish and English Neuropsychological Assessment Scales (SENAS) to demographic, cultural, and language fluency variables and to measures of cognition and independent functioning. Participants were 367 Hispanics and 160 Caucasians in the 60+ years age range, all living in the community. In Study 1, education and language use had strong influences on SENAS scores and largely explained ethnic group differences in mean scale scores. Age had weak effects on most scales except for verbal memory measures. Acculturation effects in Hispanics were largely accounted for by education and language use. Study 2 showed equivalent sensitivity of SENAS to cognitive and functional status in Hispanics and Caucasians. Results indicate that interpretation of SENAS scores must be informed by effects related to education and language fluency but provide evidence of equivalent validity in Hispanics and Caucasians with respect to concurrent measures of cognition and independent function.

Aged↗

Low folate status is associated with impaired cognitive function and dementia in the Sacramento Area Latino Study on Aging.

BACKGROUND: Low folate status is associated with poor cognitive function and dementia in the elderly. Since 1998, grain products in the United States have been fortified with folic acid, which has reduced the prevalence of folate deficiency and hyperhomocysteinemia. OBJECTIVE: We investigated whether folate status is associated with cognitive function and dementia in a cohort of elderly Latinos (aged >or= 60 y; n = 1789) exposed to folic acid fortification. DESIGN: Global cognitive function was assessed by the Modified Mini-Mental State Examination (3MSE) and specific cognitive functions by cross-culturally validated neuropsychological tests. Dementia was diagnosed according to the American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders, 3rd edition revised, and California Alzheimer Disease Diagnostic and Treatment criteria. Red blood cell (RBC) folate was measured by automated chemiluminescence and total plasma homocysteine by HPLC. RESULTS: The prevalence of folate deficiency (RBC folate <or= 160 ng/mL) was <1%. After control for confounding by homocysteine, vitamin B-12, creatinine, demographic variables, and depressive symptom score, RBC folate was directly associated with 3MSE (P = 0.005) and delayed recall (P = 0.007) scores. In addition, adjusted odds ratios for low 3MSE score (<or=78) and dementia diagnosis per unit increase in RBC folate were significantly below unity (P <or= 0.008), which indicated that the relative risks of cognitive impairment and dementia decreased with increasing RBC folate concentration. In contrast, adjusted odds ratios for low 3MSE score and dementia diagnosis per unit increase in homocysteine were not significant. CONCLUSION: RBC folate is directly associated with cognitive function scores and is inversely associated with dementia in elderly Latinos despite folic acid fortification.

Aged↗

Everyday functioning in relation to cognitive functioning and neuroimaging in community-dwelling Hispanic and non-Hispanic older adults.

The purpose of this study was to examine how a specific informant-based measure of everyday functioning, the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE; Jorm & Korten, 1988) relates to cognition and structural neuroimaging in a large multicultural, multilingual sample of Caucasians and Hispanics. Cognitive variables included selected subtests from the Spanish and English Neuropsychological Assessment Scales (SENAS; Mungas et al., 2000): Verbal Memory, Object Naming, Verbal Attention Span, Verbal Conceptual Thinking, and Pattern Recognition. The association between the IQCODE and selected neuroimaging variables, hippocampal volume and white matter hyperintensity, was evaluated in a subsample of English- and Spanish-speaking Hispanic individuals. The cognitive variables showed strong bivariate relationships with the IQCODE, although only Verbal Memory and Object Naming independently predicted level of functional ability. Verbal Memory was the strongest predictor of functional status, accounting for 23% of the variance in the IQCODE. White matter hyperintensity was also independently related to the IQCODE, accounting for 18% of the variance. Hippocampal volume was related to the IQCODE in a simple bivariate analysis, but was not an independent predictor of reported functional status after controlling for age. The relationships between cognitive variables and functional status, as well as between the imaging variables and the IQCODE, did not differ across language-ethnic groups.

Activities of Daily Living↗

Correlates of memory function in community-dwelling elderly: the importance of white matter hyperintensities.

We sought to identify magnetic resonance- (MR)-imaged structures associated with declarative memory in a community-dwelling sample of elderly Mexican-American individuals with a spectrum of cognitive decline. Measured structures were the hemispheric volumes of the hippocampus (HC), parahippocampal gyrus, and remaining temporal lobes, as well as severity of white matter signal hyperintensities (WMH). Participants were an imaged subsample from the Sacramento Area Latino Study of Aging (SALSA), N = 122. Individuals were categorized as normal, memory impaired (MI), cognitively impaired non-demented (CIND), or demented. We show that WMH was the strongest structural predictor for performance on a delayed free-recall task (episodic memory) in the entire sample. The association of WMH with delayed recall was most prominent in elderly normals and mildly cognitively impaired individuals with no dementia or impairment of daily function. However, the left HC was associated with verbal delayed recall only in people with dementia. The right HC volume predicted nonverbal semantic-memory performance. We conclude that WMH are an important pathological substrate that affects certain memory functions in normal individuals and those with mild memory loss and discuss how tasks associated with WMH may rely upon frontal lobe function.

Aged↗

Spanish and English Neuropsychological Assessment Scales (SENAS): further development and psychometric characteristics.

The Spanish and English Neuropsychological Assessment Scales were devised to be a broad set of psychometrically matched measures with equivalent Spanish and English versions. Study 1 in this report used item response theory methods to refine scales. Results strongly supported psychometric matching across English and Spanish versions and, for most scales, within English and Spanish versions. Study 2 supported in both English and Spanish subsamples the 6-domain model of ability that guided scale construction. Study 3 examined differential item functioning (DIF) of one scale (Object Naming) in relation to education, ethnicity, gender, and age. Effects of DIF on scale-level ability scores were limited. Results demonstrate an empirically guided psychometric approach to test construction for multiethnic and multilingual test applications.

Cognition↗

Plasma folate concentrations are associated with depressive symptoms in elderly Latina women despite folic acid fortification.

BACKGROUND: A relation between low folate status and depression has been recognized since the 1960s. Since 1998, flour in the United States has been fortified with folic acid, and the prevalence of folate deficiency has decreased dramatically. OBJECTIVE: We investigated whether, in this era of folic acid fortification, low folate status is a determinant of depressive symptoms in a cohort of elderly Latinos (aged >/=60 y) participating in the Sacramento Area Latino Study on Aging (SALSA). DESIGN: In a cross-sectional logistic regression analysis of data from SALSA (n = 627 M, 883 F), odds ratios (ORs) were ascertained for elevated depressive symptoms [Center for Epidemiologic Studies Depression Scale (CES-D) score >/=16] among tertiles of plasma folate. Depressive symptoms were assessed by using the CES-D. Plasma folate concentrations were determined by radioassay. RESULTS: The prevalence of folate deficiency (plasma folate </= 6.8 nmol/L) in the SALSA population was <1%. For men, no significant association between folate tertile and high CES-D score was observed. The adjusted OR for high CES-D score in women in the lowest tertile of folate was 2.04 (95% CI: 1.38, 3.02), which was significantly different from that in women in the highest tertile of folate (P < 0.001). CONCLUSION: These data indicate that, despite folic acid fortification, low folate status is associated with depressive symptoms in elderly Latina women (but not elderly Latino men).

Acculturation↗

Can dementia be prevented? Brain aging in a population-based context.

As a consequence of global aging of the human population, the occurrence of cognitive impairment and dementia is rapidly becoming a significant burden for medical care and public health systems. By the year 2020, the WHO predicts there will be nearly 29 million demented people in both developed and developing countries. Primary and secondary prevention of dementia through individual and population-level interventions could reduce this imminent risk. Vascular risk factors such as type 2 diabetes, hypertension, dietary fat intake, high cholesterol, and obesity have emerged as important influences on the risk of both vascular and Alzheimer's dementia. Understanding the reasons for differences between populations in genetic vulnerability and environmental exposures may help to identify modifiable risk factors that may lead to effective prevention of vascular and Alzheimer's dementia.

Aged↗

Impact of diabetes on cognitive function among older Latinos: a population-based cohort study.

BACKGROUND AND OBJECTIVES: Type 2 diabetes, which is highly prevalent in older Mexican Americans, may influence cognitive functioning. We examined the association of diabetes with decline in global cognitive function and memory function over a 2-year period. METHODS: Study subjects were derived from an existing cohort of Latinos aged 60 and over in the SALSA project (n=1,789). Statistical analysis was conducted using logistic regression and a generalized estimating equation (GEE). RESULTS: Logistic regression analysis indicated that baseline diabetes was a significant predictor of major cognitive impairment in Modified Mini Mental State Exam (3MSE) (OR=1.68, 95% CI=1.21, 2.34) and word-list test (OR=1.31, 95% CI=0.99, 1.75). GEE analysis showed that there was no significant difference between diabetic and nondiabetic subjects in change of cognitive scores over 2 years (3MSE, mean=-0.58, 95% CI=-1.48, 0.32; word-list test, mean=-0.10, 95% CI=-0.32, 0.11). CONCLUSIONS: More diabetic complications were associated with major cognitive decline among diabetic subjects. Research on long-term impact of treatment for type 2 diabetes is warranted.

Aged↗

Impact of antidiabetic medications on physical and cognitive functioning of older Mexican Americans with diabetes mellitus: a population-based cohort study.

PURPOSE: The current study was designed to evaluate the utility of antidiabetic medications in affecting changes in physical and cognitive functioning among older Mexican Americans with diabetes over a 2-year period. METHODS: A longitudinal analysis with repeated measurements between 1999 and 2001 was performed in a cohort of Mexican Americans, 60 or older, in the SALSA Project. Statistical analysis was conducted using a generalized estimating equation. RESULTS: For subjects with diagnosed diabetes </= 5 years (N = 381), there was less decline in physical and cognitive functioning over 2 years among subjects on treatment, compared to those without treatment. For subjects with diagnosed diabetes of 5+ years (N = 337), the effect of antidiabetic medications was more significant in preventing the decline in physical and cognitive functioning (ADL: mean in log scale = -0.10, 95% CI = -0.16, -0.04, 3MS: mean = 6.35, 95% CI = 3.23, 9.48). Combination therapy of antidiabetic agents appeared to be more effective than monotherapy in preventing the decline in physical and cognitive functioning for subjects. CONCLUSIONS: Antidiabetic drugs appear to be useful in alleviating the decline in physical and cognitive functioning among older Mexican Americans with diabetes, especially for those with a longer duration of the disease.

Activities of Daily Living↗

Prevalence of dementia in older latinos: the influence of type 2 diabetes mellitus, stroke and genetic factors.

OBJECTIVES: To estimate dementia prevalence in older Mexican Americans, determine the distribution of dementia by etiology, and evaluate the contribution of type 2 diabetes mellitus, stroke, and apolipoprotein E (ApoE) genotype to dementia. DESIGN: Analysis of baseline data from an epidemiological cohort study. SETTING: Sacramento Valley, California. PARTICIPANTS: One thousand seven hundred eighty-nine Latinos aged 60 and older residing in targeted census tracts during 1998-99. MEASUREMENTS: Each subject was interviewed and screened for dementia and cardiovascular risk factors and diseases. Fasting blood samples were drawn for glucose, insulin, and lipids. Buccal cells were obtained for genetic analysis of ApoE. A three-stage process of screening was used to diagnose dementia, including cognitive testing, a clinical examination, and imaging to determine etiology. Presence of dementia was established according to National Institute of Neurological Disorders and Stroke/Alzheimers and Related Disorders Association criteria and California Alzheimer's Disease Diagnostic and Treatment Criteria. RESULTS: Overall dementia prevalence was 4.8%. Prevalence in those aged 85 and older was 31%. Education and Anglo cultural orientation was negatively associated with dementia risk. Risk of dementia was nearly eight times higher in those with both type 2 diabetes mellitus and stroke. Forty-three percent of dementia was attributable to type 2 diabetes mellitus, stroke, or a combination of the two. ApoE allele frequency was E2 5.9%, E3 90.1%, and E4 4%. Those with any E4 and 4-4 combinations had a higher risk for dementia than those with the E3-3 combination. CONCLUSIONS: Dementia prevalence in this ethnic group is similar to that reported in Canadian and European studies but lower than in Caribbean-Hispanics residing in the United States. The etiological fraction of dementia attributable to type 2 diabetes mellitus and stroke is substantial and points toward the need for intervention research and treatment with the goal of reducing neurological sequelae in groups with high prevalence of type 2 diabetes mellitus. The allele frequency of ApoE was similar to that in other published studies on Mexican Americans. The low frequency of the E4 allele may contribute to the difference in etiology of dementia in older Mexican Americans and older people of European background. Dementia in this ethnic group may be related to preventable causes, with a smaller genetic component than in Europeans.

Age Factors↗