The study aim was to test whether the metabolic syndrome or its components predicted cognitive decline among persons aged 80 years and older (mean 85.0 years). Participants were members of the “Keys to Optimal Cognitive Aging Project,” a prospective cohort study in Okinawa, Japan. Metabolic syndrome was assessed at baseline. Cognitive functions were assessed annually for up to 3 years. One hundred and forty-eight participants completed at least one follow-up with 101 participating in all three assessments and 47 participating in two of the three assessments. The mean and median duration of follow-up were 1.8 and 2 years, respectively. Metabolic syndrome and four components were not associated with decline in global and executive cognitive functions. However, high glycosylated hemoglobin was associated with decline in memory function at the second follow-up. Our study supports accumulating evidence that the positive association between metabolic syndrome and cognitive function might not hold for the oldest old.

We studied prospectively the midlife handgrip strength, living habits, and parents’ longevity as predictors of length of life up to becoming a centenarian. The participants were 2,239 men from the Honolulu Heart Program/Honolulu–Asia Aging Study who were born before the end of June 1909 and who took part in baseline physical assessment in 1965–1968, when they were 56–68 years old. Deaths were followed until the end of June 2009 for 44 years with complete ascertainment. Longevity was categorized as centenarian (≥100 years, n = 47), nonagenarian (90–99 years, n = 545), octogenarian (80–89 years, n = 847), and ≤79 years (n = 801, reference). The average survival after baseline was 20.8 years (SD = 9.62). Compared with people who died at the age of ≤79 years, centenarians belonged 2.5 times (odds ratio (OR) = 2.52, 95% confidence interval (CI) = 1.23–5.10) more often to the highest third of grip strength in midlife, were never smokers (OR = 5.75 95% CI = 3.06–10.80), had participated in physical activity outside work (OR = 1.13 per daily hour, 95% CI = 1.02–1.25), and had a long-lived mother (≥80 vs. ≤60 years, OR = 2.3, 95% CI = 1.06–5.01). Associations for nonagenarians and octogenarians were parallel, but weaker. Multivariate modeling showed that mother’s longevity and offspring’s grip strength operated through the same or overlapping pathway to longevity. High midlife grip strength and long-lived mother may indicate resilience to aging, which, combined with healthy lifestyle, increases the probability of extreme longevity.

Background. The Free Radical Theory of Aging mechanistically links oxidative stress to aging. Okinawa has among the world's longest-lived populations but oxidative stress in this population has not been well characterized. Methods. We compared plasma lipid peroxide (LPO) and vitamin E—plasma and intracellular tocopherol levels (total α, β, and γ), in centenarians with younger controls. Results. Both LPO and vitamin E tocopherols were lower in centenarians, with the exception of intracellular β-tocopherol, which was significantly higher in centenarians versus younger controls. There were no significant differences between age groups for tocopherol: cholesterol and tocopherol: LPO ratios. Correlations were found between α-Tocopherol and LPO in septuagenarians but not in centenarians. Conclusions. The low plasma level of LPO in Okinawan centenarians, compared to younger controls, argues for protection against oxidative stress in the centenarian population and is consistent with the predictions of the Free Radical Theory of Aging. However, the present work does not strongly support a role for vitamin E in this phenomenon. The role of intracellular β-tocopherol deserves additional study. More research is needed on the contribution of oxidative stress and antioxidants to human longevity.

Objectives. To investigate the reliability and correlations with age of the balance components of the EPESE, NHANES, and the Good Balance Platform System (GBPS) in a normal population of adults. Design. Cross-sectional. Setting. Urban Medical Center in the Pacific. Participants. A random sample of 203 healthy offspring of Honolulu Heart Program participants, ages 38–71. Measurements. Subjects were examined twice at visits one week apart using the balance components of the EPESE, NHANES, and the good balance system tests. Results. The EPESE and NHANES batteries of tests were not sufficiently challenging to allow successful discrimination among subjects in good health, even older subjects. The GBPS allowed objective quantitative measurements, but the test-retest correlations generally were not high. The GBPS variables correlated with age only when subjects stood on a foam pad; they also were correlated with anthropometric variables. Conclusion. Both EPESE and NHANES balance tests were too easy for healthy subjects. The GBPS had generally low reliability coefficients except for the most difficult testing condition (foam pad, eyes closed). Both height and body fat were associated with GBPS scores, necessitating adjusting for these variables if using balance as a predictor of future health.

Although animal experiments have consistently demonstrated a positive relationship between breast cancer and energy intake, evidence from human studies remains inconclusive. In the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial cohort, 29,170 women, aged 55–75 years, who successfully completed a food frequency questionnaire (FFQ) at entry (1993–2001), were followed through 2007; 1,319 incident breast cancers were ascertained (median time from FFQ completion to diagnosis, 4.4 y). Women in the highest quartile of energy intake, relative to the lowest, had modestly, but significantly, increased breast cancer risk [multivariate relative risk (RR), 1.21; 95% confidence interval (95% CI), 1.03–1.42; Ptrend = 0.03]. Including body mass index and physical activity in the model reduced risk slightly (RR, 1.18; 95% CI, 1.00–1.39; Ptrend = 0.07). However, in similar analyses using energy intake from a FFQ administered approximately 5 years after entry (27,428 women; 806 incident breast cancers; median time from FFQ completion to diagnosis, 2.7 y), women in the highest and lowest quartiles of energy intake had similar risk. When follow-up time after the first FFQ was divided into three four-year periods, the multivariate RRs for high versus low energy intake increased from 1.21 to 1.37 to 1.55 with increasing time since dietary assessment. Although the divergent results for the two FFQs could be due to subtle questionnaire differences, our findings suggest a modest positive association between energy intake and postmenopausal breast cancer that strengthens with time since dietary assessment.

Linkage disequilibrium (LD) is an important measure used in the analysis of single-nucleotide polymorphism (SNP) data. We used the Genetic Analysis Workshop 16 (GAW16) Framingham Heart Study 500 k SNP data to explore the effect of sampling methods on estimating of LD for SNP data.

Method and data

We found 332 trios in the GAW16 Framingham SNP data. Repeated random samples without replacement, of different sizes of trios and independent individuals, are drawn from these 332 trios. For each sample, the LD is calculated using the Haploview program for the chromosome 1 SNP data. Percents of D' > 0.8 and r2 > 0.8 are calculated for different distance bins based on the Haploview output. The results are summarized by sample size and sampling methods to give us an overall view of the effect of sample size and sampling methods on the LD estimation.

Results

Trios design gave stable estimates. A sample of 30 to 40 trios gave estimates of percent of LD > 0.8 very close to those from 332 trios. When independent individuals are used, the estimates are less stable and are different from those obtained from the 332 trios for both D' and r2, with larger differences for D'.

Conclusion

Our results suggest that trio design gives a stable estimate of LD. Therefore it may be more suitable for LD analysis than using independent individuals. We must be cautious when comparing the LD estimates from trios, and those from independent individuals.

Centenarians represent a rare phenotype appearing in roughly 10–20 per 100,000 persons in most industrialized countries but as high as 40–50 per 100,000 persons in Okinawa, Japan. Siblings of centenarians in Okinawa have been found to have cumulative survival advantages such that female centenarian siblings have a 2.58-fold likelihood and male siblings a 5.43-fold likelihood (versus their birth cohorts) of reaching the age of 90 years. This is indicative of a strong familial component to longevity. Centenarians may live such extraordinarily long lives in large part due to genetic variations that either affect the rate of aging and/or have genes that result in decreased susceptibility to age-associated diseases. Some of the most promising candidate genes appear to be those involved in regulatory pathways such as insulin signaling, immunoinflammatory response, stress resistance or cardiovascular function. Although gene variants with large beneficial effects have been suggested to exist, only APOE, an important regulator of lipoproteins has been consistently associated with a longer human lifespan across numerous populations. As longevity is a very complex trait, several issues challenge our ability to identify its genetic influences, such as control for environmental confounders across time, the lack of precise phenotypes of aging and longevity, statistical power, study design and availability of appropriate study populations. Genetic studies on the Okinawan population suggest that Okinawans are a genetically distinct group that has several characteristics of a founder population, including less genetic diversity, and clustering of specific gene variants, some of which may be related to longevity. Further work on this population and other genetic isolates would be of significant interest to the genetics of human longevity.

Epidemiologic studies of pancreatic cancer risk have reported null or non-significant positive associations for obesity, while associations for height have been null. Waist and hip circumference have been evaluated infrequently.

A pooled analysis of 14 cohort studies on 846,340 individuals was conducted; 2,135 individuals were diagnosed with pancreatic cancer during follow-up. Study-specific relative risks (RRs) and 95% confidence intervals (CIs) were calculated by Cox proportional hazards models, and then pooled using a random effects model.

Compared to individuals with a body mass index (BMI) at baseline between 21–22.9kg/m2, pancreatic cancer risk was 47% higher (95%CI:23–75%) among obese (BMI≥30kg/m2) individuals. A positive association was observed for BMI in early adulthood (pooled multivariate [MV]RR = 1.30, 95%CI=1.09–1.56 comparing BMI≥25kg/m2 to a BMI between 21–22.9kg/m2). Compared to individuals who were not overweight in early adulthood (BMI<25kg/m2) and not obese at baseline (BMI<30kg/m2), pancreatic cancer risk was 54% higher (95%CI=24–93%) for those who were overweight in early adulthood and obese at baseline. We observed a 40% higher risk among individuals who had gained BMI ≥10kg/m2 between BMI at baseline and younger ages compared to individuals whose BMI remained stable. Results were either similar or slightly stronger among never smokers. A positive association was observed between waist to hip ratio (WHR) and pancreatic cancer risk (pooled MVRR=1.35 comparing the highest versus lowest quartile, 95%CI=1.03–1.78).

BMI and WHR were positively associated with pancreatic cancer risk. Maintaining normal body weight may offer a feasible approach to reducing morbidity and mortality from pancreatic cancer.

BACKGROUND

A high body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) is associated with increased mortality from cardiovascular disease and certain cancers, but the precise relationship between BMI and all-cause mortality remains uncertain.

METHODS

We used Cox regression to estimate hazard ratios and 95% confidence intervals for an association between BMI and all-cause mortality, adjusting for age, study, physical activity, alcohol consumption, education, and marital status in pooled data from 19 prospective studies encompassing 1.46 million white adults, 19 to 84 years of age (median, 58).

RESULTS

The median baseline BMI was 26.2. During a median follow-up period of 10 years (range, 5 to 28), 160,087 deaths were identified. Among healthy participants who never smoked, there was a J-shaped relationship between BMI and all-cause mortality. With a BMI of 22.5 to 24.9 as the reference category, hazard ratios among women were 1.47 (95 percent confidence interval [CI], 1.33 to 1.62) for a BMI of 15.0 to 18.4; 1.14 (95% CI, 1.07 to 1.22) for a BMI of 18.5 to 19.9; 1.00 (95% CI, 0.96 to 1.04) for a BMI of 20.0 to 22.4; 1.13 (95% CI, 1.09 to 1.17) for a BMI of 25.0 to 29.9; 1.44 (95% CI, 1.38 to 1.50) for a BMI of 30.0 to 34.9; 1.88 (95% CI, 1.77 to 2.00) for a BMI of 35.0 to 39.9; and 2.51 (95% CI, 2.30 to 2.73) for a BMI of 40.0 to 49.9. In general, the hazard ratios for the men were similar. Hazard ratios for a BMI below 20.0 were attenuated with longer-term follow-up.

CONCLUSIONS

In white adults, overweight and obesity (and possibly underweight) are associated with increased all-cause mortality. All-cause mortality is generally lowest with a BMI of 20.0 to 24.9.

Objectives

To examine whether marine-derived n-3 fatty acids (FAs) are associated with less atherosclerosis in Japanese than Whites in the United States.

Background

Marine-derived n-3 FAs at low levels are cardioprotective through their anti-arrhythmic effect.

Methods

A population-based cross-sectional study in 281 Japanese, 306 White, and 281 Japanese American men aged 40–49 was conducted to assess intima-media thickness of the carotid artery (IMT), coronary artery calcification (CAC), and serum FAs.

Results

Japanese in Japan had the lowest levels of atherosclerosis whereas Whites and Japanese Americans had similar levels. Japanese in Japan had twofold higher levels of marine-derived n-3 FAs than Whites and Japanese Americans. Japanese in Japan had significant and non-significant inverse associations of marine-derived n-3 FAs with IMT and CAC prevalence, respectively. The significant inverse association with IMT remained after adjusting for traditional cardiovascular risk factors. Neither Whites nor Japanese Americans had such associations. Significant differences between Japanese in Japan and Whites in multivariable-adjusted IMT (mean difference 39 μm (95% confidence interval (CI), 21 to 57), p<0.001) and CAC prevalence (mean difference 10.7% (95% CI, 2.9 to 18.4), p=0.007) became non-significant after further adjusting for marine-derived n-3 FAs (22 μm (95% CI, −1 to 46), p=0.065 and 5.0 % (95% CI, −5.3 to 15.4), p=0.341, respectively).

Conclusions

Very high levels of marine-derived n-3 FAs have anti-atherogenic properties independent of traditional cardiovascular risk factors and may contribute to lower burden of atherosclerosis in Japanese in Japan, which is unlikely due to genetic factors.