Long-Term Trajectories of Body Weight, Diet, and Physical Activity From Midlife Through Late Life and Subsequent Cognitive Decline in Women.
ABSTRACT: Healthy lifestyles are promising targets for prevention of cognitive aging, yet the optimal time windows for interventions remain unclear. We selected a case-control sample nested within the Nurses' Health Study (starting year 1976, mean age = 51 years), including 14,956 women aged ≥70 years who were free of both stroke and cognitive impairment at enrollment in a cognitive substudy (1995-2001). Cases (n = 1,496) were women with the 10% worst slopes of cognitive decline, and controls (n = 7,478) were those with slopes better than the median. We compared the trajectories of body mass index (weight (kg)/height (m)2), alternate Mediterranean diet (A-MeDi) score, and physical activity between groups, from midlife through 1 year preceding the cognitive substudy. In midlife, cases had higher body mass index than controls (mean difference (MD) = 0.59 units, 95% confidence interval (CI): 0.39, 0.80), lower physical activity (MD = -1.41 metabolic equivalent of task-hours/week, 95% CI: -2.07, -0.71), and worse A-MeDi scores (MD = -0.16 points, 95% CI: -0.26, -0.06). From midlife through later life, compared with controls, cases had consistently lower A-MeDi scores but a deceleration of weight gain and a faster decrease in physical activity. In conclusion, maintaining a healthy lifestyle since midlife may help reduce cognitive decline in aging. At older ages, both deceleration of weight gain and a decrease in physical activity may reflect early signs of cognitive impairment.
Project description:A study was undertaken to determine whether better cognitive functioning at midlife among more physically fit individuals reflects neuroprotection, by which fitness protects against age-related cognitive decline, or neuroselection, by which children with higher cognitive functioning select more active lifestyles.Children in the Dunedin Longitudinal Study (N?=?1,037) completed the Wechsler Intelligence Scales and the Trail Making, Rey Delayed Recall, and Grooved Pegboard tasks as children and again at midlife (age?=?38 years). Adult cardiorespiratory fitness was assessed using a submaximal exercise test to estimate maximum oxygen consumption adjusted for body weight in milliliters/minute/kilogram. We tested whether more fit individuals had better cognitive functioning than their less fit counterparts (which could be consistent with neuroprotection), and whether better childhood cognitive functioning predisposed to better adult cardiorespiratory fitness (neuroselection). Finally, we examined possible mechanisms of neuroselection.Participants with better cardiorespiratory fitness had higher cognitive test scores at midlife. However, fitness-associated advantages in cognitive functioning were already present in childhood. After accounting for childhood baseline performance on the same cognitive tests, there was no association between cardiorespiratory fitness and midlife cognitive functioning. Socioeconomic and health advantages in childhood and healthier lifestyles during young adulthood explained most of the association between childhood cognitive functioning and adult cardiorespiratory fitness.We found no evidence for a neuroprotective effect of cardiorespiratory fitness as of midlife. Instead, children with better cognitive functioning are selecting healthier lives. Fitness interventions may enhance cognitive functioning. However, observational and experimental studies testing neuroprotective effects of physical fitness should consider confounding by neuroselection.
Project description:Faster rates of age-related cognitive decline might result in early onset of cognitive impairment and dementia. The relationship between ethanol intake and cognitive decline, although studied extensively, remains poorly understood. Previous studies used single measurements of ethanol, and few were conducted in diverse populations. We assessed the association of 9-year trajectories of ethanol intake (1987-1998) with 15-year rate of decline in cognitive performance from mid- to late life (1996-2013) among 2,169 Black and 8,707 White participants of the US Atherosclerosis Risk in Communities study using multivariable linear regression models. We hypothesized that stable, low to moderate drinking would be associated with lesser 15-year cognitive decline, and stable, heavy drinking with greater 15-year cognitive decline. Stable, low to moderate drinking (for Blacks, adjusted mean difference (MD) = 0.03 (95% confidence interval (CI): -0.13, 0.19); for Whites, adjusted MD = 0.02 (95% CI: -0.05, 0.08)) and stable, heavy drinking (for Blacks, adjusted MD = 0.08 (95% CI: -0.34, 0.50); for Whites, adjusted MD = -0.03 (95% CI: -0.18, 0.11)) in midlife compared with stable never-drinking were not associated with 15-year decline in general cognitive function from mid- to late life. No association was observed for the stable former and "mostly" drinking trajectories with 15-year cognitive decline. Stable low, low to moderate, and stable heavy drinking in midlife are not associated with lesser and greater cognitive decline, respectively, from mid- to late life among Black and White adults.
Project description:In this large-scale prospective epidemiological study, we examined associations of long-term adherence to the Mediterranean diet (MeDi) and subsequent cognitive function and decline. We included 16,058 women from the Nurses' Health Study, aged ?70 y, who underwent cognitive testing by telephone 4 times during 6 y, beginning in 1995-2001, and provided repeated information on diet between 1984 and the first cognitive exam. Primary outcomes were the Telephone Interview for Cognitive Status (TICS) and composite scores of verbal memory and global cognition. MeDi adherence was based on intakes of: vegetables, fruits, legumes, whole grains, nuts, fish, red and processed meats, moderate alcohol, and the ratio of monounsaturated:saturated fat. Long-term MeDi exposure was estimated by averaging all repeated measures of diet (>13 y, on average). In primary analyses of cognitive change, the MeDi was not associated with decline in global cognition or verbal memory. In a secondary approach examining cognitive status in older age, determined by averaging all 4 repeated measures of cognition, each higher quintile of long-term MeDi score was linearly associated with better multivariable-adjusted mean cognitive scores [differences in mean Z-scores between extreme quintiles of MeDi = 0.06 (95% CI: 0.01, 0.11); = 0.05 (95% CI: 0.01, 0.08); and = 0.06 (95% CI: 0.03, 0.10) standard units; P-trends = 0.004, 0.002, and <0.001 for TICS, global cognition, and verbal memory, respectively]. These associations were similar to those observed in women 1-1.5 y apart in age. In summary, long-term MeDi adherence was related to moderately better cognition but not with cognitive change in this very large cohort of older women.
Project description:Background:Diabetes adversely impacts cognition. Lifestyle change can improve diabetes control and potentially improve cognition. We examined whether weight loss through reduced caloric intake and increased physical activity was associated with slower cognitive aging in older adults with type 2 diabetes mellitus. Methods:The Look AHEAD randomized controlled clinical trial delivered 10 years of intensive lifestyle intervention (ILI) that yielded long-term weight losses. During 5 years spanning the end of intervention and postintervention follow-up, repeated cognitive assessments were obtained in 1,091 individuals who had been assigned to ILI or a control condition of diabetes support and education (DSE). We compared the means and slopes of scores on cognitive testing over these repeated assessments. Results:Compared with DSE, assignment to ILI was associated with a -0.082 SD deficit in mean global cognitive function across repeated assessments (p = .010). However, overweight (body mass index [BMI] < 30 kg/m2) ILI participants had 0.099 (95% confidence interval [CI]: -0.006, 0.259) better mean global cognitive function compared with overweight DSE participants, while obese (BMI ? 30 kg/m2) ILI participants had -0.117 (-0.185, -0.049) SD worse mean composite cognitive function scores (interaction p = .014) compared to obese DSE participants. For both overweight and obese participants, cognitive decline was marginally (-0.014 SD/y overall) steeper for ILI participants (p = .068), with 95% CI for differences in slopes excluding 0 for measures of attention and memory. Conclusions:The behavioral weight loss intervention was associated with small relative deficits in cognitive function among individuals who were obese and marginally greater cognitive decline overall compared to control. ClinicalTrials.gov Identifier: NCT00017953.
Project description:BACKGROUND/AIMS:25-hydroxyvitamin D (25[OH]D) concentrations have been associated with cognitive decline and incident dementia in elderly populations; however, these relationships are susceptible to reverse causation. Less is known about the association of midlife 25(OH)D with long-term cognitive decline. METHODS:This was a prospective cohort study of 13,044 participants (mean age 57 years at baseline) in the Atherosclerosis Risk in Communities Study. 25(OH)D was measured from serum collected at baseline (1990-1992) using liquid chromatography tandem high-sensitivity mass spectrometry. Cognition was assessed using 3 neuropsychological tests at 3 time points, which were combined into a composite cognitive Z-score. Multivariable-adjusted linear mixed-effects models with random intercepts and slopes were used to estimate associations between 25(OH)D and cognitive change over 20 years. RESULTS:Compared to persons with sufficient 25(OH)D (?30 ng/mL), those with deficient (< 20 ng/mL) and intermediate (20-< 30 ng/mL) 25(OH)D concentrations had similar cognitive decline in composite cognitive Z-scores (deficient versus sufficient: -0.035 [95% CI -0.104 to 0.033] and intermediate versus sufficient: -0.029 [95% CI -0.080 to 0.023]). CONCLUSIONS:Lower concentrations of 25(OH)D measured in midlife were not significantly associated with more rapid cognitive decline over a 20-year follow-up period. The results of this prospective study are less susceptible to reverse causation than prior studies.
Project description:The Mediterranean dietary pattern has been associated with a decreased risk of many degenerative diseases and cognitive function in particular; however, relevant information from Mediterranean regions, where the prototype Mediterranean diet is typically adhered to, have been very limited. Additionally, predefined Mediterranean diet (MeDi) scores with use of a priori cut-offs have been used very rarely, limiting comparisons between different populations and thus external validity of the associations. Finally, associations between individual components of MeDi (i.e., food groups, macronutrients) and particular aspects of cognitive performance have rarely been explored. We evaluated the association of adherence to an a priori defined Mediterranean dietary pattern and its components with dementia and specific aspects of cognitive function in a representative population cohort in Greece.Participants from the Hellenic Longitudinal Investigation of Ageing and Diet (HELIAD), an on-going population-based study, exploring potential associations between diet and cognitive performance in a representative sample from Greek regions, were included in this analysis. Diagnosis of dementia was made by a full clinical and neuropsychological evaluation, while cognitive performance was assessed according to five cognitive domains (memory, language, attention-speed, executive functioning, visuospatial perception) and a composite cognitive score. Adherence to MeDi was evaluated by an a priori score (range 0-55), derived from a detailed food frequency questionnaire.Among 1,865 individuals (mean age 73±6 years, 41% male), 90 were diagnosed with dementia and 223 with mild cognitive impairment. Each unit increase in the Mediterranean dietary score (MedDietScore) was associated with a 10% decrease in the odds for dementia. Adherence to the MeDi was also associated with better performance in memory, language, visuospatial perception and the composite cognitive score; the associations were strongest for memory. Fish consumption was negatively associated with dementia and cognitive performance positively associated with non-refined cereal consumption.Our results suggest that adherence to the MeDi is associated with better cognitive performance and lower dementia rates in Greek elders. Thus, the MeDi in its a priori constructed prototype form may have cognitive benefits in traditional Mediterranean populations.
Project description:To conduct a systematic review of all studies to determine whether there is an association between the Mediterranean diet (MeDi) and cognitive impairment.We conducted a comprehensive search of the major databases and hand-searched proceedings of major neurology, psychiatry, and dementia conferences through November 2012. Prospective cohort studies examining the MeDi with longitudinal follow-up of at least 1 year and reporting cognitive outcomes (mild cognitive impairment [MCI] or Alzheimer's disease [AD]) were included. The effect size was estimated as hazard-ratio (HR) with 95% confidence intervals (CIs) using the random-effects model. Heterogeneity was assessed using Cochran's Q-test and I2-statistic.Out of the 664 studies screened, five studies met eligibility criteria. Higher adherence to the MeDi was associated with reduced risk of MCI and AD. The subjects in the highest MeDi tertile had 33% less risk (adjusted HR = 0.67; 95% CI, 0.55-0.81; p < 0.0001) of cognitive impairment (MCI or AD) as compared to the lowest MeDi score tertile. Among cognitively normal individuals, higher adherence to the MeDi was associated with a reduced risk of MCI (HR = 0.73; 95% CI, 0.56-0.96; p = 0.02) and AD (HR = 0.64; 95% CI, 0.46-0.89; p = 0.007). There was no significant heterogeneity in the analyses.While the overall number of studies is small, pooled results suggest that a higher adherence to the MeDi is associated with a reduced risk of developing MCI and AD, and a reduced risk of progressing from MCI to AD. Further prospective-cohort studies with longer follow-up and randomized controlled trials are warranted to consolidate the evidence. Systematic review registration number: PROSPERO 2013: CRD42013003868.
Project description:Accumulating research has linked Mediterranean diet (MeDi) adherence with slower cognitive decline and reduced Alzheimer's disease (AD) risk. However, no study to-date has examined the relationship between MeDi adherence and accumulation of cerebral A?-amyloid (A?; a pathological hallmark of AD) in older adults. Cognitively normal healthy control participants of the Australian Imaging, Biomarkers and Lifestyle (AIBL) Study of Ageing completed the Cancer Council of Victoria Food Frequency Questionnaire at baseline, which was used to construct a MeDi score for each participant (score range 0-9; higher score indicating higher adherence). Cerebral A? load was quantified by Pittsburgh Compound B positron emission tomography at baseline, 18 and 36 months: Only individuals categorised as "A? accumulators", and thus considered to be on the AD pathway, were included in the analysis (N?=?77). The relationship between MeDi adherence, MeDi components, and change in cerebral A? load (baseline to 36 months) was evaluated using Generalised Linear Modelling, accounting for age, gender, education, Apolipoprotein E ?4 allele status, body mass index and total energy intake. Higher MeDi score was associated with less A? accumulation in our cohort (??=?-0.01?±?0.004, p?=?0.0070). Of the individual MeDi score components, a high intake of fruit was associated with less accumulation of A? (??=?-0.04?±?0.01, p?=?0.00036). Our results suggest MeDi adherence is associated with reduced cerebral AD pathology accumulation over time. When our results are considered collectively with previous data linking the MeDi to slower cognitive decline, it is apparent that MeDi adherence warrants further investigation in the quest to delay AD onset.
Project description:<h4>Objective</h4>To determine if following a Mediterranean-like diet (MeDi) relates to cognitive functions and <i>in vivo</i> biomarkers for Alzheimer's disease (AD), we analyzed cross-sectional data from the German Longitudinal Cognitive Impairment and Dementia Study METHOD: The sample (n=512, mean age: 69.5±5.9 years) included 169 cognitively normal participants and subjects at higher AD risk (53 AD relatives, 209 SCD and 81 MCI). We defined MeDi adherence based on the Food Frequency Questionnaire. Brain volume outcomes were generated via voxel-based morphometry on T1-MRI and cognitive performance with an extensive neuropsychological battery. AD-related biomarkers (Aβ42/40 ratio, pTau181) in cerebrospinal fluid were assessed in n=226 individuals. We analyzed the associations between MeDi and the outcomes with linear regression models controlling for several covariates. Additionally, we applied hypothesis-driven mediation and moderation analysis.<h4>Results</h4>Higher MeDi adherence related to larger mediotemporal gray matter volume (p<0.05 FWE corrected), better memory (β±SE = 0.03 ± 0.02; p=0.038), and less amyloid (Aβ42/40 ratio, β±SE = 0.003 ± 0.001; p=0.008) and pTau181 pathology (β±SE = -1.96±0.68; p=0.004). Mediotemporal volume mediated the association between MeDi and memory (40% indirect mediation). Finally, MeDi favorably moderated the associations between Aβ42/40 ratio, pTau181 and mediotemporal atrophy. Results were consistent correcting for ApoE-ε4 status.<h4>Conclusion</h4>Our findings corroborate the view of MeDi as a protective factor against memory decline and mediotemporal atrophy. Importantly, they suggest that these associations might be explained by a decrease of amyloidosis and tau-pathology. Longitudinal and dietary intervention studies should further examine this conjecture and its treatment implications.
Project description:Previous studies examined midlife risk factors separately for old-age impaired physical and cognitive functioning. We determined the overlap of risk factors for both domains of functioning within the same setting.Biological and behavioral risk factors at age 50 years and cognitive and physical functioning were assessed 18 (SD = 5) years later in the Whitehall II study (N = 6,316). Impaired physical functioning was defined as ?1 limitation on the activities of daily living scale. Impaired cognitive functioning was defined as Mini-Mental State Examination score <27. Two statistical analyses were employed: minimally adjusted analysis (for age, sex, and ethnicity) and mutually adjusted analysis (including all risk factors). Missing data on risk factors were imputed.After confounder adjustment, impaired physical and cognitive functioning at older ages were predicted by hypertension (odds ratios [ORs] 1.80 95% confidence interval [CI] 1.39-2.33 and 1.57 95% CI 1.07-2.31, respectively), poor lung function (1.51 95% CI 1.28-1.78 and 1.31 95% CI 1.08-1.59), and physical inactivity, marginally in the case of cognitive function (1.50 95% CI 1.19-1.90 and 1.27 95% CI 0.99-1.62) at age 50 years. Impaired physical functioning but not cognitive functioning was additionally predicted by depression and higher body mass index (1.72 95% CI 1.46-2.03 and 1.29 95% CI 1.16-1.44, respectively).Several midlife risk factors are associated with impaired physical and cognitive functioning in old age, supporting a unified prevention policy. Analysis of 12 risk factors at age 50 suggests that strategies targeting physical inactivity, hypertension, and poor lung function will reduce impairments in both cognitive and physical functioning in old age.