Revisiting the hypothesis of syndromic frailty: a cross-sectional study of the structural validity of the frailty phenotype.

BACKGROUND: Fried's Phenotype Model of Frailty (PMF) postulates that frailty is a syndrome. Features of a syndrome are a heterogeneous population that can be split into at least two classes, those presenting and those not presenting the syndrome. Syndromes are characterized by a specific mixture of signs and symptoms which increase in prevalence, from less to more severe classes. So far, the null hypothesis of homogeneity - signs and symptoms of frailty cannot identify at least two classes - has been tested using Latent Class Analysis (LCA) on the five dichotomized components of PMF (unintentional weight loss, exhaustion, weakness, slowness, and low physical activity). The aim of this study is to investigate further the construct validity of frailty as a syndrome using the extension offered by Factor Mixture Models (FMM). METHODS: LCA on dichotomized scores and FMM on continuous scores were conducted to test homogeneity on the five PMF components in a sample of 1643 community-dwelling older adults living in Québec, Canada (FRéLE). RESULTS: With dichotomized LCA, three frailty classes were found: robust, prefrail and frail, and the hypothesis of homogeneity was rejected. However, in FMM, frailty was better represented as a continuous variable than as latent heterogeneous classes. Thus, the PMF measurement model of frailty did not meet the features of a syndrome in this study. CONCLUSION: Using the FRéLE cohort, the PMF measurement model validity is questioned. Valid measurement of a syndrome depends on an understanding of its etiological factors and pathophysiological processes, and on a modelling of how the measured components are linked to these processes. Without these features, assessing frailty in a clinical setting may not improve patient health. Research on frailty should address these issues before promoting its use in clinical settings.

Nutrient Patterns, Cognitive Function, and Decline in Older Persons: Results from the Three-City and NuAge Studies.

Dietary patterns, or the combination of foods and beverages intake, have been associated with better cognitive function in older persons. To date, no study has investigated the link between a posteriori nutrient patterns based on food intake, and cognitive decline in longitudinal analyses. The aim of this study was to evaluate the relationship between nutrient patterns and cognitive function and decline in two longitudinal cohorts of older persons from France and Canada. The study sample was composed of participants from the Three-City study (3C, France) and the Quebec Longitudinal Study on Nutrition and Successful Aging (NuAge, Quebec, Canada). Both studies estimated nutritional intakes at baseline, and carried out repeated measures of global cognitive function for 1,388 and 1,439 individuals, respectively. Nutrient patterns were determined using principal component analysis methodology in the two samples, and their relation with cognitive function and decline was estimated using linear mixed models. In 3C, a healthy nutrient pattern, characterized by higher intakes of plant-based foods, was associated with a higher global cognitive function at baseline, as opposed to a Western nutrient pattern, which was associated with lower cognitive performance. In NuAge, we also found a healthy nutrient pattern and a Western pattern, although no association was observed with either of these patterns in the Canadian cohort. No association between any of the nutrient patterns and cognitive decline was observed in either cohort. There is a need for longitudinal cohorts focusing on nutrient patterns with substantial follow-up, in order to evaluate more accurately associations between nutrition and cognition in older persons.

A framework for measurement and harmonization of pediatric multiple sclerosis etiologic research studies: The Pediatric MS Tool-Kit.

BACKGROUND: While studying the etiology of multiple sclerosis (MS) in children has several methodological advantages over studying etiology in adults, studies are limited by small sample sizes. OBJECTIVE: Using a rigorous methodological process, we developed the Pediatric MS Tool-Kit, a measurement framework that includes a minimal set of core variables to assess etiological risk factors. METHODS: We solicited input from the International Pediatric MS Study Group to select three risk factors: environmental tobacco smoke (ETS) exposure, sun exposure, and vitamin D intake. To develop the Tool-Kit, we used a Delphi study involving a working group of epidemiologists, neurologists, and content experts from North America and Europe. RESULTS: The Tool-Kit includes six core variables to measure ETS, six to measure sun exposure, and six to measure vitamin D intake. The Tool-Kit can be accessed online ( www.maelstrom-research.org/mica/network/tool-kit ). CONCLUSION: The goals of the Tool-Kit are to enhance exposure measurement in newly designed pediatric MS studies and comparability of results across studies, and in the longer term to facilitate harmonization of studies, a methodological approach that can be used to circumvent issues of small sample sizes. We believe the Tool-Kit will prove to be a valuable resource to guide pediatric MS researchers in developing study-specific questionnaire.

Validity and Reliability of a Short Diet Questionnaire to Estimate Dietary Intake in Older Adults in a Subsample of the Canadian Longitudinal Study on Aging.

This study assessed test-retest reliability and relative validity of the Short Diet Questionnaire (SDQ) and usability of an online 24 h recall among 232 participants (62 years ± 9.1; 49.6% female) from the Canadian Longitudinal Study on Aging (CLSA). Participants were asked to complete four 24 h dietary recalls (24HRs) using the Automated Self-Administered 24-h Dietary Assessment Tool (ASA24-Canada-2014), two SDQ administrations (prior to recalls one and four), and the System Usability Scale (SUS) for ASA24. For the SDQ administrations, Intraclass Correlation Coefficients ranged from 0.49 to 0.57 for nutrients and 0.35 to 0.72 for food groups. Mean intakes estimated from the SDQ were lower compared than those from the 24HRs. For nutrients, correlation coefficients were highest for fiber, calcium, and vitamin D (45⁻64 years: 0.59, 0.50, 0.51; >65 years: 0.29, 0.38, 0.49, p < 0.01); Kappas ranged from 0.14 to 0.37 in those 45⁻64 years and 0.17 to 0.32 in participants >65 years. Among the 70% who completed all recalls independently, the SUS indicated poor usability, though the majority reported feeling confident using ASA24. Overall, the SDQ captures intake with varying test-retest reliability and accuracy by nutrient and age. Further research is needed to inform use of a more comprehensive dietary measure in the CLSA.

Even mealtime distribution of protein intake is associated with greater muscle strength, but not with 3-y physical function decline, in free-living older adults: the Quebec longitudinal study on Nutrition as a Determinant of Successful Aging (NuAge study).

Background: Functional status declines with aging, thus impeding autonomy. Recently, a more even mealtime distribution of dietary protein was positively associated with muscle mass, but the relation of this distribution to physical performance remains unknown.Objective: We examined the relation between mealtime protein-intake distribution and physical performance and its 3-y decline in community-dwelling older adults.Design: Three-year follow-up data from 827 men and 914 women (67-84 y) in the longitudinal study on nutrition and aging [Quebec longitudinal study on Nutrition as a Determinant of Successful Aging (NuAge study); Quebec, Canada] were analyzed. Physical performance, which was measured yearly, was grouped into the following 2 functional composite scores: muscle strength (handgrip, arm, and leg) and mobility (timed-up-and-go, chair stand, and walking speed). Dietary data were collected in 2 sets of three 24-h food recalls at baseline and year 2. The individual mealtime protein distribution was calculated as the CV (i.e., SD divided by the mean) of grams of protein per meal. A mixed model analysis was used to examine trajectories of muscle strength and mobility across time by sex as conditioned by the protein distribution and adjusted for potential covariates.Results: Physical performance deteriorated over 3 y with muscle strength declining more than the mobility score in men (-1.51 ± 1.68 compared with -0.66 ± 2.81) and women (-1.35 ± 1.77 compared with -0.78 ± 2.63) (means ± SD, P < 0.001). More-evenly distributed protein intake, independent of the total quantity, was associated with a higher muscle-strength score in both sexes throughout follow-up. It was also associated with a greater mobility score, but only in men and only before adjustment for covariates. Strength and mobility rates of decline were not affected by protein-intake distribution in either sex.Conclusions: In addition to the previously observed association with lean mass, an even distribution of daily protein intake across meals is independently associated with greater muscle strength, but not with the mobility score, in older adults. A longer-term investigation of the role of protein intake and its distribution on physical performance is warranted, as are intervention studies, to support future recommendations.

A prospective evaluation of the depression-nutrient intake reverse causality hypothesis in a cohort of community-dwelling older Canadians.

Studies have investigated the potential protective effects that diet may have on late-life depression incidence. This disorder can, however, affect the person's food intake, widely known as the reverse causality hypothesis of depression. To test this hypothesis, we compared mean nutrient intakes from three 24-h recalls during the year depression was detected (Geriatric Depression Scale ≥11 or antidepressant medication) with intakes from 1 year earlier among community-dwelling older adults (67-83 years) followed up annually in the 4-year Québec Longitudinal Study on Nutrition and Aging, who were free of depression and cognitive impairment at baseline. Participants (n 158, 64·4 % female) who became depressed and had data available for all follow-up years were matched by age group and sex with non-depressed participants. General linear mixed models were adjusted for percentage changes in physical activity, functional autonomy and stressful life events reported at the time of positive screening. A significant group effect for the dietary intake of all three B-vitamins was observed, as depression cases had consistently lower dietary intakes than controls (P<0·01). Over time, intakes of dietary vitamin B12 declined within depressed participants in bivariate analysis, but there was no time×group effect for any nutrient tested in the multivariate analyses. Intakes of energy, protein, saturated fat and total dietary fibre did not change in cases v. CONTROLS: Among community-dwelling older adults, declines in dietary vitamins B6, B12 and folate may precede depression incidence. To help preventative efforts by programmes and practitioners, longitudinal cohorts of longer duration should investigate the extent of the decline in dietary intakes relative to the time of depression.

A lower ratio of omega-6 to omega-3 fatty acids predicts better hippocampus-dependent spatial memory and cognitive status in older adults.

OBJECTIVE: Evidence from several cross-sectional studies indicates that an increase in omega-6 to omega-3 fatty acids (FAs) may negatively affect cognition in old age. The hippocampus is among the first neural structures affected by age and atrophy in this brain region is associated with cognitive decline. Therefore, we hypothesized that a lower omega-6:3 FA ratio would predict better hippocampus-dependent spatial memory, and a higher general cognitive status. METHOD: Fifty-two healthy older adults completed a Food Frequency Questionnaire, the Montreal Cognitive Assessment test (MoCA; a test of global cognition) and virtual navigation tasks that assess navigational strategies and spatial memory. RESULTS: In this cross-sectional study, a lower ratio of omega-6 to omega-3 FA intake strongly predicted more accurate hippocampus-dependent spatial memory and faster learning on our virtual navigation tasks, as well as higher cognitive status overall. CONCLUSIONS: These results may help elucidate why certain dietary patterns with a lower omega-6:3 FA ratio, like the Mediterranean diet, are associated with reduced risk of cognitive decline. (PsycINFO Database Record

Outcome of a Targeted Nutritional Intervention Among Older Adults With Early-Stage Alzheimer's Disease: The Nutrition Intervention Study.

A 6-month dietary intervention program was designed for community-dwelling older adults with Alzheimer's disease. Sixty-seven persons aged 70 years and above were recruited with their caregivers from six hospital memory and geriatric outpatient clinics, and allocated to intervention ( n = 34 dyads) or control group ( n = 33 dyads). Usual diet was assessed by a validated food frequency questionnaire and current diet by two nonconsecutive diet recalls or records corroborated by caregivers, at recruitment (T1) and exit from the study (T2). Intervention participants received targeted dietary recommendations; control participants received Canada's Food Guide leaflets. The program was assessed using paired and independent t tests and nonparametric statistics. Fat intakes increased at T2 within intervention participants (54 ± 16 vs. 67 ± 23 g, p = .013), and there was a tendency for higher energy, protein, and calcium intakes at T2 within this group. Proportions with adequate protein intakes almost doubled from T1 to T2 in intervention group women ( p = .028) but decreased in female controls ( p = .030). Longer follow-up is necessary to determine persistence of benefits.

Risk and protective factors for heat-related events among older adults of Southern Quebec (Canada): The NuAge study.

OBJECTIVES: Extreme heat is known to increase heat-related health outcomes (HRHO). Incidence and predictors of HRHO were examined among older adults living in Quebec (Canada). METHOD: This prospective five-year study used data from the first follow-up of community-dwelling older adults from the NuAge cohort (2005-2006), located in three health regions of Southern Quebec. Medical, social and environmental factors, identified in Health Canada guidelines (2011), were used to develop the Older Adult Health Vulnerability Index (OAHVI). HRHO, obtained from a medico-administrative database, were defined as events occurring on a hot day (maximal temperature ≥30°C) between 2006 and 2010. Two outcomes were examined: heat-related 1) emergency department presentations (EDPs) and 2) health events (i.e., EDP, hospitalizations or deaths). Multivariate logistic regressions were performed to assess the associations between risk and protective factors, including OAHVI, and both outcomes. RESULTS: EDP and hospitalizations were, respectively, 2.6 (95% CI: 2.0-3.5) and 1.7 (95% CI: 1.1-2.6) times more frequent on hot days compared to normal summer days. Low household income and disability increased risk of heat-related EDP (AOR = 3.20; 95% CI: 1.16-8.81 and AOR = 2.66; 95% CI: 1.15-6.14 respectively) and health events (AOR = 2.84; 95% CI: 1.06-7.64 and AOR = 2.51; 95% CI: 1.13-5.61 respectively). High social participation was a protective factor of heat-related EDP (AOR = 0.05; 95% CI: 0.01-0.20) and health events (AOR = 0.04; 95% CI: 0.01-0.18). Older adults presenting ≥6 OAHVI factors out of 9 were 7-8 times more at risk of heat-related EDP (OR = 7.40; 95% CI: 1.51-36.19) and health events (OR = 7.77; 95% CI: 1.63-37.20) compared to participants having 0-1 factor. CONCLUSION: Social participation, reduced autonomy and low income were predictors of HRHO. The OAHVI, also a strong predictor, should help clinicians identify high-risk elderly patients.

Dietary assessment is a critical element of health research - Perspective from the Partnership for Advancing Nutritional and Dietary Assessment in Canada.

Challenges and complexities associated with assessing dietary intakes are numerous, but not insurmountable. This opinion paper from Canadian researchers draws attention to the importance of building capacity and providing funding opportunities for research in dietary assessment methods in Canada and elsewhere. Such strategies would contribute to a better understanding of the roles played by diet in human health and better translation of this information into the most meaningful and effective dietary guidelines, policies, and interventions.

Relation between mealtime distribution of protein intake and lean mass loss in free-living older adults of the NuAge study.

BACKGROUND: Studies have shown that an even protein intake distribution across meals increased 24-h muscle protein synthesis in young adults compared with a skewed intake. Whether this short-term result translates into long-term preservation of lean mass (LM) in older adults remains unknown. OBJECTIVE: The aim was to examine the extent to which protein quantity and distribution are associated with LM and appendicular LM (aLM), and their 2-y decline, in community-dwelling older adults. DESIGN: Baseline and 2-y follow-up data from 351 men and 361 women (aged 67-84 y) in the NuAge study (Quebec Longitudinal Study on Nutrition as a Determinant of Successful Aging) with available body-composition data (by dual-energy X-ray absorptiometry) were used. Food intake was assessed with the use of three 24-h food recalls collected at baseline and 3 collected at the 2-y follow-up. Protein distribution across meals was calculated as the CV of protein ingested per meal, with lower values reflecting evenness of protein intake. Linear mixed-model analysis was performed to examine changes in LM and aLM across time, by sex, as conditioned by the quantity and distribution of protein intake, adjusted for potential covariates. RESULTS: Over 2 y, LM declined in both men (-2.5% ± 4.0%) and women (-2.0% ± 3.4%) (P < 0.05), whereas aLM loss was not significant (men: -1.5% ± 4.8%; women: -1.2% ± 5.3%; P > 0.05). The decline in LM was not independently affected by the quantity and distribution of protein intake. Yet men and women with evenly distributed protein intakes and men with high protein intakes showed higher LM or aLM throughout the entire follow-up period, even after potential confounders were controlled for (P < 0.05). CONCLUSIONS: Our results suggest that greater protein intakes and a more even distribution across meals are modifiable factors associated with higher muscle mass in older adults but not with losses over 2 y. Interventional studies should determine longer-term effects on preserving LM with aging.

The food environment and diet quality of urban-dwelling older women and men: Assessing the moderating role of diet knowledge.

OBJECTIVES: The relationships between local food environments and dietary patterns are important for older adults and could be different in men and women. We examined associations between exposure to neighbourhood food sources and food consumption and the moderating role of diet knowledge separately among older women and men living in Montreal in 2003-2005 (n = 722). METHODS: The proportion of fast-food outlets relative to all restaurants (%FFO) and the proportion of healthy food stores relative to all stores (%HFS) were estimated for 500 m buffers around participants' homes. Two dietary patterns, designated "Western" and "prudent", reflecting lower- and higher-quality diets respectively, were identified from food frequency questionnaire data. The unique and interactive effects of diet knowledge and food-source exposure on diet scores were tested with separate linear regression models for women and men. RESULTS: For men, greater %FFO exposure was related to lower prudent diet scores (ß = -0.18, p = 0.02), but no effect of %HFS exposure was observed and no interactions were statistically significant. For women, an inverse relationship between %FFO and prudent diet scores was strongest among those with low diet knowledge (ß = -0.22, p < 0.01). No other associations were statistically significant. CONCLUSION: Older men's diet patterns may reflect unhealthy cues associated with fast-food outlets. Among women, diet knowledge potentiated both negative and positive relationships with the food environment. In the absence of consistent main effects of the food environment on diet scores, subgroup analysis is a promising avenue for research.

Nutrient Patterns and Their Food Sources in Older Persons from France and Quebec: Dietary and Lifestyle Characteristics.

BACKGROUND: Dietary and nutrient patterns have been linked to health outcomes related to aging. Food intake is influenced by environmental and genetic factors. The aim of the present study was to compare nutrient patterns across two elderly populations sharing a common ancestral cultural background, but living in different environments. METHODS: The diet quality, lifestyle and socioeconomic characteristics of participants from the Three-City Study (3C, France, n = 1712) and the Québec Longitudinal Study on Nutrition and Successful Aging (NuAge, Quebec, Canada, n = 1596) were analyzed. Nutrient patterns and their food sources were identified in the two samples using principal component analysis. Diet quality was compared across sample-specific patterns by describing weekly food intake and associations with the Canadian Healthy Eating Index (C-HEI). RESULTS: Three nutrient patterns were retained in each study: a healthy, a Western and a more traditional pattern. These patterns accounted for 50.1% and 53.5% of the total variance in 3C and NuAge, respectively. Higher education and non-physical occupations over lifetime were associated with healthy patterns in both studies. Other characteristics such as living alone, having a body mass index lower than 25 and being an ex-smoker were associated with the healthy pattern in NuAge. No association between these characteristics and the nutrient patterns was noted in 3C. The healthy and Western patterns from each sample also showed an inverse association with C-HEI. CONCLUSION: The two healthy patterns showed important similarities: adequate food variety, consumption of healthy foods and associations with common sociodemographic factors. This work highlights that nutrient patterns derived using a posteriori methods may be useful to compare the nutritional quality of the diet of distinct populations.

Energy and protein intakes and their association with a decline in functional capacity among diabetic older adults from the NuAge cohort.

PURPOSE: Diabetic older adults (OA) are at greater risk of muscle strength (MS) loss and functional capacity (FC) decline than non-diabetics. Protein and energy intakes are important determinants of muscle mass and MS maintenance and indirectly affect FC. The study sought to determine whether low protein and energy intakes were associated with FC decline and whether this association was mediated by MS in diabetic OA over a 3-year follow-up, in secondary analyses of the Quebec Longitudinal Study on Nutrition and Successful Aging. METHODS: In 172 diabetic OA (62 % men, mean age = 75 years), FC decline was defined as the change between SMAF (Système de Mesure de l'Autonomie Fonctionnelle) scores at baseline (T1) and 3 years later (T4). Baseline adequate protein and energy intakes were set at ≥1 g/kg BW and ≥30 kcal/kg BW, respectively. Sex-stratified linear regressions were controlled for confounding variables. RESULTS: Mean body weight (BW) was 85.42 ± 13.8 in men and 79.7 ± 11.5 in women (p ≤ .001). Adequate protein intake in women was associated with lesser FC decline (mean ± SE) (2.11 ± 0.81 vs. 4.91 ± 0.72; p = .029), while adequate energy intake was not associated with FC decline either in men or in women. In women, 1 g protein/kg BW helped maintain MS, hence minimizing FC decline. CONCLUSIONS: These results demonstrate that protein intake is important in maintaining FC in diabetic OA, albeit with sex differences. This study provides further evidence that protein requirements may be greater than the 0.8 g/kg BW currently recommended for OA. Future research in larger samples over longer follow-up is needed to confirm these results.

Individual and collective factors predicting change in diet quality over 3 years in a subset of older men and women from the NuAge cohort.

PURPOSE: This study examined individual and collective factors as predictors of change in global diet quality (DQ). METHODS: Subjects were 373 older adults (57 % female) aged 68-82 years at recruitment (T1) into the NuAge Cohort Study, and followed for three years. Data were collected by questionnaires, physical performance tests and anthropometric measurements. Diet was assessed at T1 and T4 using three non-consecutive 24-h diet recalls (24HR) and DQ (Canadian Healthy Eating Index), and was computed on the means of the 24HR. DQ change over three years was determined as "DQT4-DQT1". Baseline (T1) measures significantly correlated with DQ at T1 were entered into backward stepwise linear regression analyses along with selected theoretical constructs and controlled for baseline DQ to determine predictors of change in DQ over 3 years. RESULTS: Among men, education (p = .009) and sensations of hunger (p = .01) were positive predictors of DQ change over time, while DQ at T1 (p < .0001), cognition (p = .003) and social network (p = .019) were negative predictors (adjusted R (2) = 30.4 %). Finally, among women, diet knowledge (p = .044) was a positive predictor of DQ change, while DQ at T1 (p < .0001) and social network (p = .033) were negative predictors of DQ change over 3 years (adjusted R (2) = 24.1 %). CONCLUSIONS: These results can inform dietary intervention programmes targeting gender-specific determinants of diet quality in older adults.

Relation entre la mastication et la qualité de l'alimentation des aînés de l'Étude longitudinale québécoise sur la nutrition et le vieillissement (NuAge).

The objective of this study was to assess the relationship between the quality of mastication and dietary intake among community-dwelling older adults (67-84 years). A secondary analysis of data collected upon entry of participants in the NuAge study was effected. Perceived masticatory efficiency (n=1793) was measured using a questionnaire inspired by the Oral Health Impact Profile. Direct assessment of masticatory efficiency was carried out in a subsample (n=94), using a validated clinical test (Swallowing Threshold Test Index, 0-100%). Dietary intake was calculated from three non-consecutive 24h recalls. Mean scores indicate good perceived masticatory efficiency (Men:26.22±0.19/28;Women:25.81±0.21/28), but weak assessed efficiency (Men:60.8% [CI(57.3-64.2)]; Women:61.2% [CI(57.7-64.7)]). Multivariate regression analysis, adjusting for confounding variables (age, sex, schooling, living alone, income, smoking, chronic conditions, functional autonomy), showed that masticatory efficiency (measured or perceived) was not associated with intake of fruits/vegetables, protein, vitamin C or folic acid.

Prevalence of risk and protective factors associated with heat-related outcomes in Southern Quebec: A secondary analysis of the NuAge study.

OBJECTIVES: Heat vulnerability is increasing owing to climate change, aging and urbanization. This vulnerability may vary geographically. Our study examined the prevalence and distribution of risk and protective factors of heat-related outcomes among older adults across three health regions of Southern Quebec (Canada). METHOD: This secondary cross-sectional study used data from the 1st follow-up of the NuAge longitudinal study, a cohort of community-dwelling older adults, aged 68-82 years at baseline, of three health regions: Eastern Townships, Montreal and Laval. Prevalence of factors, identified in Health Canada guidelines, was measured. An Older Adult Heat Vulnerability Index (OAHVI) simultaneously considering medical, social and environmental factors was constructed. The distribution of each factor and OAHVI was examined across the three regions. Results were weighted for age, sex (overall and region-specific analyses) and region (overall analyses). RESULTS: Ninety percent of participants had ≥1 risk factor, the most prevalent being: cardiovascular medication (50.8%), hypertension (46.7%), living alone (39.2%), cardiovascular disease (36.9%), living in an urban heat island (34.7%) and needing help in activities of daily living (26.5%). Two thirds of participants had ≥1 protective factor, the most prevalent being talking on the phone daily (70.9%). Heat vulnerability varied greatly by region and this variation was mainly attributable to social and environmental rather than medical factors. According to the OAHVI, 87.2% of participants cumulated ≥2 factors (median = 3.0 factors/participant). CONCLUSION: Our results support the need for small-scale assessment of heat vulnerability. This study could help stakeholders tackle heat-related illness and develop regionally tailored prevention programs.

Prevention of Age-Related Cognitive Decline: Which Strategies, When, and for Whom?

Brain aging is characterized by the progressive and gradual accumulation of detrimental changes in structure and function, which increase risk of age-related cognitive decline and dementia. This devastating chronic condition generates a huge social and economic burden and accounts for 11.2% of years of disability. The increase in lifespan has contributed to the increase in dementia prevalence; however, there is currently no curative treatment for most causes of dementias. This paper reviews evidence-based strategies to build, enhance, and preserve cognition over the lifespan by examining approaches that work best, proposing when in the life course they should be implemented, and in which population group(s). Recent work shows a tendency to decreased age-specific prevalence and incidence of cognitive problems and dementia among people born later in the first half of the 20th century, citing higher educational levels, improvements in lifestyle, and better handling of vascular risk factors. This implies that we can target modifiable environmental, lifestyle, and health risk factors to modify the trajectory of cognitive decline before the onset of irreversible dementia. Because building cognitive reserve and prevention of cognitive decline are of critical importance, interventions are needed at every stage of the life course to foster cognitive stimulation, and enable healthy eating habits and physical activity throughout the lifespan. Preventive interventions to decrease and delay cognitive decline and its consequences in old age will also require collaboration and action on the part of policy-makers at the political and social level.

Evaluation of the Relative Validity of the Short Diet Questionnaire for Assessing Usual Consumption Frequencies of Selected Nutrients and Foods.

A 36-item Short Diet Questionnaire (SDQ) was developed to assess usual consumption frequencies of foods providing fats, fibre, calcium, vitamin D, in addition to fruits and vegetables. It was pretested among 30 community-dwelling participants from the Québec Longitudinal Study on Nutrition and Successful Aging, "NuAge" (n = 1793, 52.4% women), recruited in three age groups (70 ± 2 years; 75 ± 2 years; 80 ± 2 years). Following revision, the SDQ was administered to 527 NuAge participants (55% female), distributed among the three age groups, both sexes and languages (French, English) prior to the second of three non-consecutive 24 h diet recalls (24HR) and validated relative to the mean of three 24HR. Full data were available for 396 participants. Most SDQ nutrients and fruit and vegetable servings were lower than 24HR estimates (p < 0.05) except calcium, vitamin D, and saturated and trans fats. Spearman correlations between the SDQ and 24HR were modest and significant (p < 0.01), ranging from 0.19 (cholesterol) to 0.45 (fruits and vegetables). Cross-classification into quartiles showed 33% of items were jointly classified into identical quartiles of the distribution, 73% into identical and contiguous quartiles, and only 7% were frankly misclassified. The SDQ is a reasonably accurate, rapid approach for ranking usual frequencies of selected nutrients and foods. Further testing is needed in a broader age range.

Assessing Older Adults' Masticatory Efficiency.

OBJECTIVES: To determine internal consistency and criterion validity of a questionnaire assessing perception of masticatory efficiency in community-dwelling older adults. DESIGN: Secondary cross-sectional analysis of baseline data from the Québec Longitudinal Study on Nutrition and Successful Aging (NuAge). SETTING: NuAge is a 5-year (2003-08) observational study of 1,793 men and women aged 67 to 84 in good general health at recruitment. PARTICIPANTS: A sample of 1,789 was used to determine internal consistency of the questionnaire. A subsample (n = 94) of the cohort who underwent a clinical test directly measuring masticatory efficiency was used to determine criterion validity of the questionnaire. MEASUREMENTS: The questionnaire was a subset of the Oral Health Impact Profile containing 7 Likert-scale questions (score 0-28 points). Masticatory efficiency was assessed using a validated clinical test measuring ability to chew a raw carrot (Swallowing Threshold Test Index, score 0-100%). For perceived and measured data, a higher score indicated better masticatory efficiency. RESULTS: Internal consistency of the questionnaire was deemed good (Cronbach alpha = 0.803). Mean scores were generally high (men, 25.3, 95% confidence interval (CI) = 24.7-25.9; women, 24.3, 95% CI = 23.7-25.0), indicating good perceived masticatory efficiency for men and women. Mean performance test scores were low (men, 60.8%, 95% CI = 57.3-64.2; women, 61.2%, 95% CI = 57.7-64.7). No significant relationship between perceived and measured masticatory efficiency was observed (Pearson correlation coefficient = -0.14, P = .22). CONCLUSION: Despite good internal consistency of the questionnaire and the recognized validity of the test, people's perception of their masticatory efficiency does not reflect objective efficiency as measured using a clinical test.