Low density lipoprotein related receptor protein 1 (LRP1) is a multi-functional endocytic receptor that is highly expressed in adipocytes and the hypothalamus. Animal models and in vitro studies support a role for LRP1 in adipocyte metabolism and leptin signaling, but genetic polymorphisms have not been evaluated for obesity in people. We examined whether dietary fats (eg., saturated, polyunsaturated) modulated the association of LRP1 variants with anthropometric traits. We studied a population-based sample of Puerto Ricans (n=920, aged 45–74 y) living in the Boston area. In multivariable linear regression models, we dichotomized saturated fat intake and found significant interaction terms between total saturated fatty acids and LRP1 rs1799986 genotype for BMI (P=0.006) and hip (P=0.002). High intake of saturated fat was associated with higher BMI (P=0.001), waist (P=0.008) and hip (P=0.003) in minor allele carriers (CT+TT) compared to CC participants. Further analysis of dichotomized individual saturated fatty acids revealed that interactions were strongest for two individual longer chain fatty acids. High intake of palmitic acid (C16:0; P=0.0007) and high stearic acid intake (C18:0; P=0.005) were associated with higher BMI in T carriers. Interactions were not detected for polyunsaturated fatty acids. Gene-diet interactions at the LRP1 locus support the hypothesis that susceptibility to weight gain based on saturated fatty acids is modified by genotype and possibly by chain length. These results may facilitate the development of a panel of genetic candidates for use in optimizing dietary recommendations for obesity management.
single nucleotide polymorphisms; saturated fatty acids; fatty acid chain length; Puerto Ricans
Puerto Ricans experience a high prevalence of several chronic conditions, including metabolic syndrome. Genetic variants of the CD36 gene have been associated with metabolic syndrome. We aimed to determine the association between 6 single nucleotide polymorphisms (SNPs) for CD36 and metabolic syndrome and its components in Puerto Ricans (45-75 y) living in the Greater Boston area.
Associations between each SNP, metabolic syndrome and its components were examined using multivariate logistic regression models. Haplotype trend regression analysis was used to determine associations between haplotypes and metabolic syndrome.
For two SNPs of CD36 (rs1049673 and rs3211931), homozygous subjects of the minor allele (G and T, respectively) were associated with a higher likelihood of metabolic syndrome (odd ratio (OR) (95% confidence interval (CI): 1.89 (1.0, 3.5) and 1.77 (1.0, 3.1), respectively) relative to carriers of the major allele. Although CD36 haplotypes were not significantly associated with metabolic syndrome overall (global significance, P=0.23), one haplotype (G-C-C vs. C-C-C (reference haplotype) was marginally associated (P=0.049).
SNPs of CD36 were associated with metabolic syndrome in Puerto Ricans. Prospective studies should further explore the role of CD36 variants in the development of this condition.
Puerto Rican; Hispanic; CD36; metabolic syndrome
Epidemiologic research is increasingly being focused on elderly persons, many of whom exhibit mild-to-moderate cognitive impairment. This presents a challenge for collection and interpretation of self-reported dietary data. There are few reports on the impact of cognitive function and dementia on the validity of self-reported dietary intakes. Using plasma phospholipid fatty acid profiles as a biomarker of intake, the authors assessed the validity of an interviewer-administered food frequency questionnaire (FFQ) to estimate intakes of 2 marine-based omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), among 273 community-dwelling adults aged ≥60 years participating in the Nutrition, Aging, and Memory in Elders Study (Boston, Massachusetts, 2002–2008). Age- and energy-adjusted Pearson correlation coefficients for correlations between dietary intakes and plasma phospholipids were consistent across categories of high and low cognitive function (r = 0.48), based on Mini-Mental State Examination score, and were similar across clinically diagnosed categories of normal functioning (r = 0.49), mild cognitive impairment (r = 0.45), and dementia (r = 0.52). The FFQ ranked 78% of subjects to within 1 quartile of their plasma phospholipid EPA + DHA quartile. This frequency was consistently high across all cognitive categories. With interviewer administration, this FFQ seems to be a valid method of assessing dietary EPA + DHA intake in older adults with mild-to-moderate cognitive impairment.
aged; aged, 80 and over; dementia; epidemiologic methods; fatty acids, omega-3; mental recall; nutrition assessment; questionnaires
We examined the cross-sectional relationship between dietary vitamin B6 and plasma pyridoxyl-5′-phosphate concentrations (PLP) with depressive symptomatology among a representative sample of 618 elderly Caribbean Hispanics, and a neighborhood based comparison group of 251 non-Hispanic white (NHW) older adults in Massachusetts.
Depressive symptomatology was assessed with the Center for Epidemiologic Studies Depression Scale (CES-D). 41% of Hispanics and 22.6% of NHWs had CES-D scores greater than 16, indicating depressive caseness. Dietary intake was calculated from a semi-quantitative food frequency questionnaire (FFQ) designed for this population.
PLP was significantly associated with CES-D score and depressive caseness in the total sample and in non-supplement users. Deficient levels of plasma PLP (plasma PLP < 20 nmol/L) approximately doubled the likelihood of depressive caseness. Total intake (diet + supplement) of vitamin B6 was not associated with these outcomes. However, dietary vitamin B6 was significantly associated with CES-D score and depressive caseness.
Longitudinal studies are needed to clarify the direction of causality between vitamin B6 and depressive symptoms.
Polyunsaturated fatty acids (PUFAs) may influence bone health. The objective of this work was to examine associations between plasma phosphatidylcholine (PC) PUFA concentrations and hip measures: (1) femoral neck bone mineral density (FN-BMD) (n = 765); (2) 4-year change in FN-BMD (n = 556); and (3) hip fracture risk (n = 765) over 17-year follow-up among older adults in the Framingham Osteoporosis Study. BMD measures were regressed on quintile of plasma PC PUFAs (docosahexaenoic acid [DHA], linoleic acid [LA], and arachidonic acid [AA]), adjusted for covariates. Hazard ratios (HR) and 95% confidence interval (CI) for hip fracture were estimated by quintile of plasma PC PUFAs, adjusted for covariates. Higher concentrations of PC DHA were associated with loss of FN-BMD over 4 years in women (p-trend = 0.04), but was protective in men in the uppermost quintile compared to men grouped in the lower four quintiles, in post hoc analysis (p = 0.01). PC LA concentrations were inversely associated with baseline FN-BMD in women (p-trend = 0.02), and increased hip fracture risk in women and men (p-trend = 0.05), but body mass index (BMI) adjustment attenuated these associations (p-trend = 0.12 and p-trend = 0.14, respectively). A trend toward a protective association was observed between PC AA and baseline FN-BMD in men (p-trend = 0.06). Women and men with the highest PC AA concentrations had 51% lower hip fracture risk than those with the lowest (HR = 0.49, 95% CI = 0.24–1.00). Opposing effects of PC DHA on FN-BMD loss observed in women and men need further clarification. Bone loss associated with PC LA may be confounded by BMI. High PC AA concentrations may be associated with reduced hip fracture risk.
DOCOSAHEXAENOIC ACID; LINOLEIC ACID; ARACHIDONIC ACID; BMD; FRACTURE
Brain-derived neurotrophic factor (BDNF) has been associated with regulation of body weight and appetite. The goal of this study was to examine the interactions of a functional variant (rs6265) in the BDNF gene with dietary intake for obesity traits in the Boston Puerto Rican Health Study. BDNF rs6265 was genotyped in 1147 Puerto Rican adults and examined for association with obesity-related traits. Men (n = 242) with the GG genotype had higher BMI (P = 0.009), waist circumference (P = 0.002), hip (P = 0.002), and weight (P = 0.03) than GA or AA carriers (n = 94). They had twice the risk of being overweight (BMI ≥ 25) relative to GA or AA carriers (OR = 2.08, CI = 1.02–4.23, and P = 0.043). Interactions between rs6265 and polyunsaturated fatty acids (PUFA) intake were associated with BMI, hip, and weight, and n-3 : n-6 PUFA ratio with waist circumference in men. In contrast, women (n = 595) with the GG genotype had significantly lower BMI (P = 0.009), hip (P = 0.029), and weight (P = 0.027) than GA or AA carriers (n = 216). Women with the GG genotype were 50% less likely to be overweight compared to GA or AA carriers (OR = 0.05, CI = 0.27–0.91, and P = 0.024). In summary, BDNF rs6265 is differentially associated with obesity risk by sex and interacts with PUFA intake influencing obesity traits in Boston Puerto Rican men.
Major sources of flavonoids were identified, and mean intakes over several decades were reported, among 1638 participants (mean age 62.1 +/− 16.0 y), of the Baltimore Longitudinal Study of Aging (BLSA). Dietary data were collected using 7-day diet records during three time periods (1980s, 1990s and 2000-present), and the USDA flavonoid, proanthocyanidin and isoflavone databases were used to estimate dietary flavonoid intakes. Dietary intake data were divided according to decade of visit. Foods were matched with appropriate foods in the USDA databases. Mixed dishes were disaggregated to individual foods and a similar procedure was followed. Total flavonoids and five sub-classes of flavonoids, including flavonols, flavones, flavanones, flavan-3-ols and anthocyanidins, were computed by summing appropriate compounds. The median intakes of flavonoids and the contributions of various foods to intakes were calculated by decade. Age and sex adjusted mean (SE) daily intakes of flavonoids increased from 250 (7.4) in the 1980s to 280 (9.9) mg in the 2000s. Top contributors of flavonoids were tea, apple/pear (and juices), citrus fruits (and juices), peaches, plums, grapes, nectarines (and juices) and chocolate. The data show an increase in the consumption of flavonoids over the three decades, which appears to be related to intake of fruit.
Flavonoids; Antioxidants; Aging; Diet records; Database; Food data management; Food composition
Connexins are a widespread family of membrane proteins that assemble into hexameric hemichannels, also known as connexons. Connexons regulate membrane permeability in individual cells or couple between adjacent cells to form gap junctions and thereby provide a pathway for regulated intercellular communication. We have now examined the role of connexins in platelets, blood cells that circulate in isolation, but upon tissue injury adhere to each other and the vessel wall to prevent blood loss and facilitate wound repair.
Methods and Results
We report the presence of connexins in platelets, notably connexin37, and that the formation of gap junctions within platelet thrombi is required for the control of clot retraction. Inhibition of connexin function modulated a range of platelet functional responses prior to platelet-platelet contact, and reduced laser induced thrombosis in vivo in mice. Deletion of the Cx37 gene (Gja4) in transgenic mice reduced platelet aggregation, fibrinogen binding, granule secretion and clot retraction indicating an important role for Cx37 hemichannels and gap junctions in platelet thrombus function.
Together, these data demonstrate that platelet gap junctions and hemichannels underpin the control of haemostasis and thrombosis and represent potential therapeutic targets.
Connexin37; Gap junction; Haemostasis; Platelets; Thrombosis
Cereal fibre and whole-grain intakes have been consistently associated in the epidemiological literature with reduced mortality and risk of chronic disease including obesity, CVD and type 2 diabetes. The present review focuses on intervention trials with three primary aims: (1) understanding the mechanisms through which fibre consumption improves health (for example, examination of intermediate endpoints reflecting improved lipid, glucose and energy metabolism); (2) close evaluation of qualitative factors which modify fibre’s effectiveness including physiochemical properties (for example, solubility, fermentability and viscosity), fibre extract molecular weight, fibre particle size and botanical structure of the fibre source grain; and (3) identification of areas in which additional research is needed. The first two aims typify the goals of nutrition research, in that improved understanding of the specific factors which determine fibre’s health benefits has critical implications for dietary recommendations as well as improving understanding of physiological mechanisms. The third aim acknowledges the substantial gap between recommended and actual fibre intakes in many developed countries including the USA and the UK. In recognition of this deficit in total fibre intake, food manufacturing processes increasingly utilise fibre extracts and concentrates as food additives. However, whether fibre extracts provide similar health benefits to the fibre supplied in the constituents of whole grain is largely unexplored. The relative benefits of fibre extracts compared with whole-grain fibre sources therefore represent a critical area in which additional research is needed.
Dietary fibre; Whole grains; Clinical trials; Cereal fibre
Type 2 Diabetes (T2D) and particulate air pollution are associated with inflammatory dysregulation. We assessed the modifying effects of diabetes medications on the association of C-reactive protein (CRP), a marker of inflammation, and traffic exposure in adults with T2D (n=379). CRP concentrations were significantly positively associated with residence ≤100 m of a roadway, >100m and ≤200m of a roadway and increased traffic density for individuals using insulin. For individuals using oral hypoglycemic medications (OHAs), CRP was significantly negatively associated with residence >100 m - ≤200 m of a roadway and multiple roadway exposure in an interaction model. Among people with diabetes, individuals on insulin appear to be most vulnerable to the effects of traffic exposure. Disease severity among insulin users may promote the pro-inflammatory response to traffic exposure, though diabetes medications may also modify the response. Possible anti-inflammatory effects of OHAs with traffic exposure merit further evaluation.
Residential traffic exposure; C-reactive protein; Type 2 diabetes; Traffic proximity; Traffic density; Puerto Rican; Inflammation
Depression is associated with an increase in the incidence of type 2 diabetes, but the mechanism is unclear. We aimed to study the relationship between depression and glycemic intake in the elderly, and examine whether antidepressant use modified this relationship.
Design, Setting and Participants
We evaluated 976 homebound elders in a cross-sectional study. Depressed was defined by having a Center for Epidemiological Studies Depression (CES-D) score ≥ 16. Antidepressant use was documented. Glycemic index (GI), Glycemic load (GL), and fasting blood insulin levels were measured.
Depressed elders had slightly higher GI (Mean ± SD: 55.8 ± 3.8 vs. 55.1 ± 3.7, P = 0.003) and higher insulin levels (Median: 84.0 vs. 74.4 pmole/ml, P = 0.05) than non-depressed elders. Depressed elders receiving antidepressants, primarily selective serotonin reuptake inhibitors (SSRI), had lower GI (Mean ± SD: 55.1 ± 4.7 vs. 56.2 ± 3.4, P = 0.002) and GL (Median: 170.3 vs. 6826.3, P = 0.03) than those not taking antidepressants. After adjusting for potential confounding variables, GI remained positively associated with depression (β = + 0.65, SE = 0.28, P = 0.02); logarithm of GL was positively associated with depression (β = + 0.33, SE = 0.17, P = 0.05) and negatively associated with antidepressant use (β = − 0.54, SE = 0.18, P = 0.003).
Prospective studies are needed to examine whether high glycemic intake is a mediating factor between late life depression and the risk of type 2 diabetes.
To examine associations between variants of genes involved in the uptake, retention and metabolism of folate and depressive symptoms, and whether such associations are direct or through mediation by folate or homocysteine.
We performed a cross-sectional analysis of data from 976 Puerto Rican adults, aged 45-75 years, residing in the greater Boston area, Massachusetts. Twelve single nucleotide polymorphisms (SNPs) in genes involved in folate uptake, retention and metabolism were investigated. These include folate hydrolase (FOLH1), folate polyglutamate synthase (FPGS), r-glutamyl hydrolase (GGH), methylene tetrahydrofolate reductase (MTHFR), methionine synthase (MTR), proton-coupled folate transporter (PCFT), and reduced folate carrier (RFC1). The Center for Epidemiologic Studies Depression Scale (CES-D) was used to measure depressive symptoms.
The FOLH1 rs61886492 C>T (or 1561C>T) polymorphism was significantly associated with lower CES-D score (p = .0025), after adjusting for age, sex, population admixture, smoking, and educational attainment. Individuals with the TT and TC genotypes were 49% less likely (odds ratio (OR): 95% confidence interval [CI]: 0.51: 0.29, 0.89) to report mild depressive symptoms (CES-D score ≥16 & ≤26) and 64% less likely (OR: 95% CI: 0.36: 0.18, 0.69) to report moderate to severe depressive symptoms (CES-D score >26), compared to those with the CC genotype. No significant mediation effects by plasma folate or homocysteine on the associations between this SNP and CES-D score were observed.
The FOLH1 1561C>T polymorphism may be associated with risk of depressive symptoms.
Depressive symptoms; genetics; polymorphisms; folate; folate hydrolase; glutamate carboxypeptidase II
The proportion of Latin American population > 60 y is expected to double during the next few decades. Metabolic syndrome (MetS) is associated with high morbidity and mortality worldwide. However, little is known about MetS in Latin America in general, and in Ecuador in particular.
To examine the prevalence of MetS and its association with blood micronutrient, homocysteine (tHcy) and CRP concentrations in elderly living in a low-income urban area.
We performed a cross-sectional study. MetS, using the International Diabetes Federation definition, dietary intake and plasma micronutrient, CRP and tHcy concentrations were assessed.
352 elderly (≥65 y)
MetS was prevalent (40 %)—considerably more so among women (81%) than men (19%) (X2 = 32.6, P<0.0001). Further, 53 % of those without MetS exhibited two or more of its components. Micronutrient deficiencies were prevalent including those of vitamin C, zinc, B12, and folate. Vitamin C and E concentrations were inversely (OR= 0.78, CI = 0.71 – 0.86; OR= 0.16, CI =0.03 – 0.81, respectively), and CRP (OR=1.79, CI =1.04 – 3.06) was positively associated with MetS.
The co-existence of MetS with micronutrient deficiencies suggests that elderly Ecuadorians suffer from the double burden of diseases that is increasingly observed in less-developed countries. More research is needed to determine causal factors, but results presented suggest that these older adults would benefit from interventions to reduce the risk factors for MetS, in particular, higher consumption of micronutrient-rich foods.
Elderly; metabolic syndrome; Ecuador; micronutrient deficiency; C-reactive protein
The effect of protein on bone is controversial, and calcium intake may modify protein's effect on bone. We evaluated associations of energy-adjusted tertiles of protein intake (ie, total, animal, plant, animal/plant ratio) with incident hip fracture and whether total calcium intake modified these associations in the Framingham Offspring Study. A total of 1752 men and 1972 women completed a baseline food frequency questionnaire (1991–1995 or 1995–1998) and were followed for hip fracture until 2005. Hazard ratios (HRs) were estimated using Cox proportional hazards regression adjusting for confounders. Baseline mean age was 55 years (SD 9.9 years, range 26 to 86 years). Forty-four hip fractures occurred over 12 years of follow-up. Owing to significant interaction between protein (total, animal, animal/plant ratio) and calcium intake (p interaction range = .03 to .04), stratified results are presented. Among those with calcium intakes less than 800 mg/day, the highest tertile (T3) of animal protein intake had 2.8 times the risk of hip fracture [HR = 2.84, 95% confidence interval (CI) 1.20–6.74, p = .02] versus the lowest tertile (T1, p trend = .02). In the 800 mg/day or more group, T3 of animal protein had an 85% reduced hip fracture risk (HR = 0.15, 95% CI 0.02–0.92, p = .04) versus T1 (p trend = .04). Total protein intake and the animal/plant ratio were not significantly associated with hip fracture (p range = .12 to .65). Our results from middle-aged men and women show that higher animal protein intake coupled with calcium intake of 800 mg/day or more may protect against hip fracture, whereas the effect appears reversed for those with lower calcium intake. Calcium intake modifies the association of protein intake and the risk of hip fracture in this cohort and may explain the lack of concordance seen in previous studies. © 2010 American Society for Bone and Mineral Research.
NUTRITION; PROTEIN INTAKE; HIP FRACTURE; CALCIUM; COHORT STUDY
DNA oxidative stress has been suggested as an important pathogenic mechanism in
cognitive impairment and dementia. With baseline data collected from 2004 to
2008, the authors examined whether urinary 8-hydroxy-2-deoxyguanosine (8-OHdG),
a biomarker of global DNA oxidation, was associated with cognitive function in a
sample of 1,003 Puerto Rican adults, aged 45–75 years, living in
Boston, Massachusetts, and the surrounding area. Cognitive function was measured
by using a battery of 7 tests: the Mini-Mental State Examination, word list
learning, digit span, clock drawing and figure copying, Stroop, and verbal
fluency tests. The primary outcome was a global cognitive score, averaging
standardized scores across all cognitive tests. A higher 8-OHdG concentration
was significantly associated with lower global cognitive scores, after
adjustment for age, education, status of the gene for apolipoprotein E
(APOE), and other covariates
(Ptrend = 0.01). The difference in the
global score, comparing participants in the 2 extreme 8-OHdG quartiles, was
−0.11 (95% confidence interval: −0.20, −0.02),
which was equivalent to accelerating cognitive aging by about 4 years, as
observed in this population. Prospective studies are needed to elucidate whether
elevated urinary 8-OHdG concentrations can predict the rate of cognitive decline
and incident dementia.
biological markers; DNA damage; Hispanic Americans; neurobehavioral manifestations; oxidative stress
Puerto Ricans living in the United States mainland present multiple disparities in prevalence of chronic diseases, relative to other racial and ethnic groups. Allostatic load (AL), or the cumulative wear and tear of physiological responses to stressors such as major life events, social and environmental burden, has been proposed as a possible mechanism for the inequalities observed in minority groups, but has not been studied in Puerto Ricans. The aim of this study was to determine the association of AL to six chronic diseases (abdominal obesity, hypertension, diabetes, and self-reported cardiovascular disease (CVD), arthritis and cancer) in Puerto Ricans, and to contrast AL to metabolic syndrome (MetS). Participants of the Boston Puerto Rican Health Study (n=1,116, ages 45–75 years) underwent a home-based interview, where questionnaires were completed and biological samples collected. A summary definition of AL was constructed using clinically-defined cutoffs and medication use for 10 physiological parameters in different body systems. Logistic regression models were run to determine associations between AL score and disease status, controlling for age, sex, smoking, alcohol use, physical activity, total fat intake and energy intake. Parallel models were also run with MetS score replacing AL. We found that increasing categories of AL score were significantly associated with abdominal obesity, hypertension, diabetes and self-reported cardiovascular disease (CVD) and arthritis, but not with self-reported cancer. The strength of associations of AL with all conditions, except diabetes and cancer, was similar to or larger than those of MetS score. In conclusion, Puerto Rican older adults experienced physiological dysregulation that was associated with increased odds of chronic conditions. AL was more strongly associated with most conditions, compared to MetS, suggesting that this cumulative measure may be a better predictor of disease. These results have prospective research implications for Puerto Ricans and other ethnic groups.
allostatic load; health disparities; Puerto Ricans; chronic diseases; metabolic syndrome; USA
Dietary antioxidants such as vitamin C may play a role in bone health. We evaluated associations of vitamin C intake (total, dietary and supplemental) with incident hip fracture and non-vertebral osteoporotic fracture, over a 15 to 17-y follow-up, in the Framingham Osteoporosis Study.
366 men and 592 women (mean age 75 yr ± 5) completed a food frequency questionnaire (FFQ) in 1988–89 and were followed for non-vertebral fracture until 2003 and hip fracture until 2005. Tertiles of vitamin C intake were created from estimates obtained using the Willett FFQ, after adjusting for total energy (residual method). Hazard Ratios were estimated using Cox-proportional hazards regression, adjusting for covariates.
Over follow-up 100 hip fractures occurred. Subjects in the highest tertile of total vitamin C intake had significantly fewer hip fractures (P trend=0.04) and non-vertebral fractures (P trend=0.05) compared to subjects in the lowest tertile of intake. Subjects in the highest category of supplemental vitamin C intake had significantly fewer hip fractures (P trend=0.02) and non-vertebral fractures (P trend=0.07) compared to non-supplement users. Dietary vitamin C intake was not associated with fracture risk (all P>0.22).
These results suggest a possible protective effect of vitamin C on bone health in older adults.
ageing; bone; fracture; nutrition; population studies; vitamin C
The objective of this study was to examine the association between 25-hydroxyvitamin D, 25(OH)D, and cognitive function.
A cross-sectional investigation of 25(OH)D and cognition was completed in 377 black and 703 non-black (mainly Caucasian) elders (65–99 years) participating in the nutrition and memory in elders study. Participants underwent a comprehensive neuropsychological battery, and 25(OH)D concentrations were obtained.
More than 65% of elders had suboptimal 25(OH)D concentrations (≤20 ng/mL or ≤50 nmol/L). Approximately 18% were deficient in 25(OH)D (<10 ng/mL or <25 nmol/L). After adjusting for age, sex, race, body mass index, education, center, kidney function, seasonality, physical activity, and alcohol use, 25(OH)D was associated with better performance on trails A (β = –0.49, p < .03), trails B (β = –0.73, p < .02), digit symbol (β = 0.19, p < .001), matrix reasoning (β = 0.04, p < .02), and block design (β = 0.07, p < .04) tests. Associations remained after adjustment for homocysteine, apoE4 allele, plasma B vitamins, and multivitamin use (y/n). 25(OH)D concentrations >20 ng/mL were associated with better performance on tests of executive function, including trails A (80.5 vs 95, p < .05), trails B (205s vs 226s, p < .05), matrix reasoning (7.8 vs 7.0, p = .03), and digit symbol (31.5 vs 37, p < .01). There were no associations between 25(OH)D and memory tests. Factor analysis yielded factors for memory, executive function, and attention/processing speed. After adjustment, 25(OH)D was associated with the executive function (β = 0.01, p < 0.01) and attention/processing speed factors (β = 0.01, p = .03), but not the memory factor (β = –0.001, p = 0.65).
25(OH)D was positively associated with cognitive performance, particularly with measures of executive function in this elderly population.
Cognitive function; Vitamin D; Elderly people; Dementia
Traffic exposure may increase cardiovascular disease (CVD) risk via systemic inflammation and elevated blood pressure, two important clinical markers for managing disease progression.
We assessed degree and consistency of association between traffic exposure indicators as predictors of C-reactive protein (CRP) and pulse pressure (PP) in an adult U.S. Puerto Rican population (n = 1,017).
Cross-sectional information on health and demographics and blood data was collected. Using multiple linear regression, we tested for associations between CRP, PP, and six traffic exposure indicators including residential proximity to roads with > 20,000 vehicles/day and traffic density [vehicle miles traveled per square mile (VMT/mi2)]. Diabetes and obesity [body mass index (BMI) ≥ 30 kg/m2] were tested as effect modifiers.
CRP was positively associated with traffic density in the total population [36% CRP difference with 95% confidence interval (CI) 2.5–81%] for residence within the highest versus lowest VMT/mi2 level. With BMI ≥ 30, CRP showed significant positive associations with five of six traffic indices including residence ≤ 200 m versus > 200 m of a roadway [22.7% CRP difference (95% CI, 3.15–46.1)] and traffic density in the third highest versus lowest VMT/mi2 level [28.1% difference (95% CI, 1.0–62.6)]. PP was positively associated with residence within ≤ 100 m of a roadway for the total population [2.2 mmHg (95% CI, 0.13–4.3 mmHg)] and persons with BMI ≥ 30 [3.8 mmHg (95% CI, 0.88–6.8)]. Effect estimates approximately doubled for residence within ≤ 200 m of two or more roadways, particularly in persons with diabetes [8.1 mmHg (95% CI, 2.2–14.1)].
Traffic exposure at roadway volumes as low as 20,000–40,000 vehicles/day may increase CVD risk through adverse effects on blood pressure and inflammation. Individuals with elevated inflammation profiles, that is, BMI ≥ 30, may be more susceptible to the effects of traffic exposure.
C-reactive protein; inflammation; Puerto Rican; pulse pressure; residential traffic exposure; traffic analysis zone; traffic density; traffic proximity
Adipose (adp) is an obesity gene in Drosophila and mice with crucial functions in fat metabolism. We investigated the correlation between genetic variation of the WDTC1 locus, the ortholog of adp, and human obesity. Five WDTC1 single nucleotide polymorphisms (SNPs) were genotyped in 935 and 1115 adults of two ethnically diverse US populations. In the Boston Puerto Rican population, we demonstrated that two WDTC1 SNPs strongly associated with obesity. Homozygote and heterozygote carriers of the major allele i22835A, representing about 96% of the population, had significantly higher mean BMI (31.5 and 31.0 kg/m2, respectively) than non-carriers (28.6 kg/m2). Conversely, homozygotes of the minor allele i22835G were leaner and were 74% less likely to be overweight or obese (OR=0.26, P=0.003) compared to homozygote carriers of the major allele. Haplotype analyses based on two SNPs further supported these findings. In addition, we found a strong interaction of monounsaturated fatty acid (MUFA) intake by genotype in this population. As dietary MUFA intake increased, minor allele carriers of SNPs i22835A>G had higher BMIs, whereas major allele carriers had lower BMIs. A White population also exhibited a pattern of association between WDTC1 genotypes and obesity although of a different nature. Those WDTC1 variants associated with obesity likely have experienced strong positive selection in human history, when food supply was unpredictable. Given the high frequency of the major alleles in both populations, we suggest that WDTC1 variation may be an important risk factor contributing to obesity in these populations.
WDTC1; adipose; obesity; overweight; BMI
With the upsurge in online dietary modification programmes, online dietary assessment tools are needed to capture food intake. Although the DASH (Dietary Approaches to Stop Hypertension) diet is recommended by the US Department of Agriculture, there are no online instruments that capture DASH food servings. Our objective was to assess the validity of a new, short, online dietary questionnaire developed to capture intake of DASH food servings. The DASH Online Questionnaire (OLQ) was validated against the well-known Block Food Frequency Questionnaire (FFQ).
This was a cross-sectional validation of the DASH OLQ, which contained eleven food groups (breakfast cereals; dairy; drinks; fats and oils; fruits; grains and snacks; meat, fish and poultry; mixed dishes; sweets; vegetables; and nuts, seeds and legumes). Each subject completed a DASH OLQ once weekly for four weeks and one 98.2 Block FFQ (110 questions) between weeks 2 and 4. DASH OLQ were averaged and then compared with the Block FFQ for nutrient intakes as well as intakes of DASH food groups.
Boston University Medical Center, Boston, Massachusetts.
One hundred and ninety-one faculty and staff at Boston University Medical Center aged 20–70 years.
There were significant positive correlations between the Block FFQ and the DASH OLQ for all food groups ranging from r=0·8 for the nuts/seeds/legumes category to r = 0·3 for vegetables and mixed dishes. A comparison of nutrient intakes found strong positive correlations in all nutrient categories. Of particular interest in the DASH diet and the web-based nutrition and physical activity programme were total fat (r=0·62), total carbohydrate (r=0·67), total K (r=0·68), total Ca (r =0·69), total vitamin C (r=0·60) and total energy intake (r=0·68).
The DASH OLQ captures food and nutrient intake well in relation to the more established Block FFQ.
Diet; Dietary pattern; Food frequency; Food intake; Energy intake; Dietary assessment; Questionnaire; Validation; Internet; Online; Web-based; DASH diet; Block FFQ
Psychological stress can contribute to health disparities in populations that are confronted with the recurring stress of everyday life. A number of biomarkers have been shown to be affected by psychological stress. These biomarkers include allostatic load, which is a summary measure of the cumulative biological burden of the repeated attempts to adapt to daily stress. Allostatic load includes effects on the hypothalamic-pituitary axis, the sympathetic nervous system and the cardiovascular system. These in turn affect the immune system via bidirectional signaling pathways. Evidence is also building that psychological stress, perhaps via heightened inflammatory states, can increase oxidative stress levels and DNA damage. The inter-relationships of ethnicity, genotype, gene expression and ability to adequately mitigate stress response are just starting to be appreciated. The need to conduct these studies in disadvantaged populations is clear and requires methods to address potential logistical barriers. Biomarkers can help characterize and quantify the biological impact of psychological stress on the etiology of health disparities.
Psychosocial stress; health disparities; allostatic load; oxidative stress
Older Puerto Ricans living in the continental U.S. suffer from higher rates of diabetes, obesity, cardiovascular disease and depression compared to non-Hispanic White populations. Complex diseases, such as these, are likely due to multiple, potentially interacting, genetic, environmental and social risk factors. Presumably, many of these environmental and genetic risk factors are contextual. We reasoned that racial background may modify some of these risk factors and be associated with health disparities among Puerto Ricans. The contemporary Puerto Rican population is genetically heterogeneous and originated from three ancestral populations: European settlers, native Taíno Indians, and West Africans. This rich mixed ancestry of Puerto Ricans provides the intrinsic variability needed to untangle complex gene-environment interactions in disease susceptibility and severity. Herein, we determined whether a specific ancestral background was associated with either of four major disease outcomes (diabetes, obesity, cardiovascular disease and depression). We estimated the genetic ancestry of 1129 subjects from the Boston Puerto Rican Health Study, based on genotypes of 100 ancestry informative markers (AIMs). We examined the effects of ancestry on tests of association between single AIMs and disease traits. The ancestral composition of this population was 57.2% European, 27.4% African, and 15.4% Native American. African ancestry was negatively associated with type 2 diabetes and cardiovascular disease, and positively correlated with hypertension. It is likely that the high prevalence rate of diabetes in Africans, Hispanics, and Native Americans is not due to genetic variation alone, but to the combined effects of genetic variation interacting with environmental and social factors.
population admixture; Puerto Ricans; ancestry informative markers
The Boston Puerto Rican Health Study is an ongoing longitudinal cohort study designed to examine the role of psychosocial stress on presence and development of allostatic load and health outcomes in Puerto Ricans, and potential modification by nutritional status, genetic variation, and social support.
Self-identified Puerto Ricans, aged 45-75 years and residing in the Boston, MA metro area, were recruited through door-to-door enumeration and community approaches. Participants completed a comprehensive set of questionnaires and tests. Blood, urine and salivary samples were extracted for biomarker and genetic analysis. Measurements are repeated at a two-year follow-up.
A total of 1500 eligible participants completed baseline measurements, with nearly 80% two-year follow-up retention. The majority of the cohort is female (70%), and many have less than 8th grade education (48%), and fall below the poverty level (59%). Baseline prevalence of health conditions is high for this age range: considerable physical (26%) and cognitive (7%) impairment, obesity (57%), type 2 diabetes (40%), hypertension (69%), arthritis (50%) and depressive symptomatology (60%).
The enrollment of minority groups presents unique challenges. This report highlights approaches to working with difficult to reach populations, and describes some of the health issues and needs of Puerto Rican older adults. These results may inform future studies and interventions aiming to improve the health of this and similar communities.
Our objective was to identify major dietary sources of whole grains and to describe the construction of a database of whole grain content of foods. Dietary information was collected with 7-d food records from men and women in the Baltimore Longitudinal Study of Aging, mean age 62.1 ± 16.0 years, who participated in the dietary assessment portion of the study (n = 1516), and estimates of whole grain intake were obtained from a newly developed database. The Pyramid Servings database and 1994–1996 Continuing Survey of Food Intakes by Individuals (CSFII) recipe ingredients database were then used to calculate both servings and gram weights of whole grain intakes. Mean intakes of whole grains, refined grains, and total grains, as well as frequency of intake for major whole grain food groups and whole grain content for each group, were calculated. Top contributors of whole grains were ready-to-eat breakfast cereals (made with whole grain as well as bran), hot breakfast cereals (made with whole grain), multi-grain bread, and whole wheat bread. While more research is needed to better understand the benefits of whole grains, the development of research tools, including databases to accurately assess whole grain intake, is a critical step in completing such research.
Whole grains; Wheat; Bran; Germ; Fiber; Database; Food composition