Cognitive Performance Among Older Persons in Japan and the United States.

OBJECTIVE: To compare cognitive performance among Japanese and American persons, aged 68 years and older, using two nationally representative studies and to examine whether differences can be explained by differences in the distribution of risk factors or in their association with cognitive performance. DESIGN: Nationally representative studies with harmonized collection of data on cognitive functioning. SETTING: Nihon University Japanese Longitudinal Study of Aging and the US Health and Retirement Study. PARTICIPANTS: A total of 1953 Japanese adults and 2959 US adults, aged 68 years or older. MEASUREMENTS: Episodic memory and arithmetic working memory are measured using immediate and delayed word recall and serial 7s. RESULTS: Americans have higher scores on episodic memory than Japanese people (0.72 points on a 20-point scale); however, when education is controlled, American and Japanese people did not differ. Level of working memory was higher in Japan (0.36 on a 5-point scale) than in the United States, and the effect of education on working memory was stronger among Americans than Japanese people. There are no differences over the age of 85 years. CONCLUSION: Even with large differences in educational attainment and a strong effect of education on cognitive functioning, the overall differences in cognitive functioning between the United States and Japan are modest. Differences in health appear to have little effect on national differences in cognition. J Am Geriatr Soc 68:354-361, 2020.

Diagnosis and Control of Hypertension in the Elderly Populations of Japan and the United States.

The Japanese have the highest life expectancy in the world while the United States (U.S.) has relatively low life expectancy. Furthermore, the Americans have relatively poorer health compared to the Japanese. Examination of the treatment of specific conditions such as hypertension in these two countries may provide insights into how the health care system contributes to the relative health in these two countries. In this study, we focus on the treatment of hypertension, as this is the most common condition requiring therapeutic interventions in seniors. This study examines hypertension diagnoses and controls in nationally representative samples of the older populations (68 years-or-older) of Japan and the U.S. Data come from two nationally representative samples: the Nihon University Japanese Longitudinal Study of Aging (NUJLSOA) (n=2,309) and the U.S. Health and Retirement (HRS) Study (n=3,517). The overall prevalence of hypertension is higher in Japan than the U.S. Undiagnosed hypertension is about four times higher in Japan than in the U.S., while the control of blood pressure is more than four times higher in the U.S. than in Japan. Thus, the use of antihypertensive medication is much more frequent and more effective in the U.S. The medical care system seems to be more effective in controlling hypertension in the U.S. than in Japan. This may be due to the more aggressive diagnosis and treatment of hypertension in the U.S.

Sociodemographic correlates of four indices of blood pressure and hypertension among older persons in Japan.

BACKGROUND: High blood pressure is a significant risk factor for cardiovascular disease and mortality. Japan has traditionally had higher levels of measured blood pressure than many Western countries, and reducing levels of hypertension has been a major focus of Japanese health policy over recent decades. In the West, hypertension is strongly associated with sociodemographic and behavioral (smoking and body mass index, BMI) factors; studies of the association between sociodemographic factors and biological indicators have not been fully explored in the elderly population of Japan using nationally representative survey data. OBJECTIVE: To describe hypertension prevalence rates with increasing age and to examine the link between sociodemographic and behavioral factors (including age, gender, education, residence, smoking, and BMI) and measures of blood pressure and overall hypertension in the Japanese population aged ≥68 years. METHODS: Data were collected in 2006 during the fourth wave of the Nihon University Japanese Longitudinal Study of Aging, a nationally representative sample of those ≥68. The analytic sample includes 2,634 participants. Pulse pressure, systolic, diastolic, and mean blood pressure, as well as hypertension, were regressed on sociodemographic and behavioral factors. RESULTS: There is no significant difference in the prevalence of overall hypertension by age for men and women from ages 68-69 to 90+. Higher BMI and older age were linked to higher blood pressure and higher chance of having hypertension. More years of education and being female were associated with a lower likelihood of measured hypertension. Smoking, rural residence, and living alone were not significantly associated with the outcome measures. CONCLUSION: The increase in hypertension with higher BMI raises concerns about future health in Japan as BMI increases. The lack of a relationship between smoking and any measure of blood pressure or hypertension is an indicator that smoking may have different effects in Japan than in other countries. Because there is no effect of living alone on blood pressure, compliance with drug regimes may not be enhanced by living with others in Japan.

Oral health problems and mortality.

BACKGROUND/PURPOSE: Previous studies have shown the relationship between individual oral health conditions and mortality; however, the relationship between mortality and multiple oral health conditions has not been examined. This study investigates the link between individual oral health problems and oral comorbidity and mortality risk. MATERIALS AND METHODS: Data are derived from the National Health and Nutrition Examination Survey 1999-2004, which is linked to the National Death Index for mortality follow-up through 2006. We estimated the risk of mortality among people with three individual oral health conditions-tooth loss, root caries, and periodontitis as well as with oral comorbidity-or having all three conditions. RESULTS: Significant tooth loss, root caries, and periodontal disease were associated with increased odds of dying. The relationship between oral health conditions and mortality disappeared when controlling for sociodemographic, health, and/or health behavioral indicators. Having multiple oral health problems was associated with an even higher rate of mortality. CONCLUSION: Individual oral health conditions-tooth loss, root caries, and periodontal disease-were not related to mortality when sociodemographic, health, and/or health behavioral factors were considered, and there was no differential pattern between the three conditions. Multiple oral health problems were associated with a higher risk of dying.

Behavioral disinhibition and reduced anxiety-like behaviors in monoamine oxidase B-deficient mice.

Monoamine oxidase (MAO) B catalyzes the degradation of beta-phenylethylamine (PEA), a trace amine neurotransmitter implicated in mood regulation. Although several studies have shown an association between low MAO B activity in platelets and behavioral disinhibition in humans, the nature of this relation remains undefined. To investigate the impact of MAO B deficiency on the emotional responses elicited by environmental cues, we tested MAO B knockout (KO) mice in a set of behavioral assays capturing different aspects of anxiety-related manifestations, such as the elevated plus maze, defensive withdrawal, marble burying, and hole board. Furthermore, MAO B KO mice were evaluated for their exploratory patterns in response to unfamiliar objects and risk-taking behaviors. In comparison with their wild-type (WT) littermates, MAO B KO mice exhibited significantly lower anxiety-like responses and shorter latency to engage in risk-taking behaviors and exploration of unfamiliar objects. To determine the neurobiological bases of the behavioral differences between WT and MAO B KO mice, we measured the brain-regional levels of PEA in both genotypes. Although PEA levels were significantly higher in all brain regions of MAO B KO in comparison with WT mice, the most remarkable increments were observed in the striatum and prefrontal cortex, two key regions for the regulation of behavioral disinhibition. However, no significant differences in transcript levels of PEA's selective receptor, trace amine-associated receptor 1 (TAAR1), were detected in either region. Taken together, these results suggest that MAO B deficiency may lead to behavioral disinhibition and decreased anxiety-like responses partially through regional increases of PEA levels.