Taro Fukaya

Oral intake of Lactobacillus pentosus strain b240 accelerates salivary immunoglobulin A secretion in the elderly: A randomized, placebo-controlled, double-blind trial

BackgroundImmunoglobulin A (IgA) secretion in saliva decreases with age and may be the cause of increased vulnerability of the elderly to respiratory infections. The effect of oral intake of lactic acid bacteria on salivary secretory IgA (SIgA) in the elderly has not been reported. The objective of this study was to demonstrate the acceleration of salivary SIgA secretion by oral intake of Lactobacillus pentosus strain b240 (b240) in the elderly.ResultsA total of 80 healthy elderly individuals were randomly allocated to either an intervention (i.e., b240) or a control (i.e., placebo) group. The elderly individuals in the b240 group were given a sterile water beverage (125 mL) containing heat-killed b240 (4 × 109 cells), while those in the placebo group were given only a sterile water beverage (125 mL); both groups received their respective beverages once daily for 12 weeks. Saliva was collected before initiation of the study and every 2 weeks thereafter. Saliva flow rate and SIgA concentration were determined, and the SIgA secretion rate was calculated. The mean salivary SIgA secretion rate in the b240 group steadily increased until week 4 (exhibiting a 20% elevation relative to that at week 0), and then remained stable until week 12. Changes in SIgA secretion rate over the intervention period were significantly greater in the b240 group than in the placebo group. The treatment groups exhibited no significant differences in adverse events.ConclusionsOral intake of L. pentosus strain b240 for 12 weeks significantly accelerated salivary SIgA secretion, thereby indicating its potential utility in the improvement of mucosal immunity and resistance against infection in the elderly.

Trends in Old-Age Functioning and Disability in Japan: 1993-2002

Disability is a burden to individuals and society. Population ageing, combined with the fact that disability is most common among the elderly, has focused attention on trends in old-age disability. This study estimates trends in functioning and disability among Japanese elderly from 1993 to 2002 and contrasts the patterns with those found in the USA. Japan is an especially interesting country because its age structure is relatively old, and it currently has the highest life expectancy in the world despite the fact that just 50 years ago its life expectancy was in the bottom half of all countries. As in the USA, disability rates have fallen. If it were not for the gains in disability between 1993 and 2002, there would have been 1.1 million more disabled elderly in 2002. The reductions were experienced broadly across socio-demographic and economic groups. Increases in education across cohorts are associated with the declines in disability.

Changes in Functional Status Among Older Adults in Japan: Successful and Usual Aging.

This research aimed to chart the trajectories of functional status in old age in Japan and to assess how self-rated health and cognitive functioning differentiate these trajectories and account for interpersonal differences. Data came from a 5-wave panel study of a national sample of 2,200 Japanese older adults between 1987 and 1999. The sample as a whole showed an accelerated increase in functional limitations with age. approximated by a quadratic function. More important, 3 major trajectories of functional change were identified: (a) minimal functional decrement, (b) early onset of functional impairment. and (c) late onset of functional impairment. These findings may serve as useful benchmarks for observations derived from other developed nations.

Gender differences in old age mortality: Roles of health behavior and baseline health status

This research aims to further current understanding of gender differences in old age mortality. In particular, it assesses the relative importance of health behavior and baseline health conditions in predicting the risk of dying, and how their effects differ between elderly men and women. Data for this research came from a prospective study of a national sample of 2,200 older adults in Japan from 1987 to 1999. Hazard rate models were employed to ascertain the interaction effects involving gender and health behavior (i.e., smoking and drinking) and baseline health status. Gender differences in old age mortality in the Japanese are quite pronounced throughout all of our models. In addition, interaction effects of gender and smoking, functional limitation, and cognitive impairment, indicate that females in Japan suffer more from these risk factors than do their male counterparts. Failure to adjust for population heterogeneity may lead to a significant underestimation of female advantage in survival. The inclusion of health behavior and health status measures only offsets a limited proportion of this gender differential. The increased mortality risk due to smoking, functional limitation, and cognitive impairment among elderly Japanese women suggests that narrowing of gender gap in mortality may be due to not only changes in the levels of these risk factors but also their differential effects on men and women.

Predictors of Improvement or Decline in Instrumental Activities of Daily Living among Community-Dwelling Older Japanese

Background: To explore predictors of functional improvement or decline in instrumental activities of daily living (IADL) among community-dwelling older people. Methods: Of all the residents (≧65 years, n = 1,673) living in Yoita town, Niigata prefecture, Japan, in 2000, 1,544 subjects who participated in the baseline interview survey (T1) were followed up until 2002 (T2). A wide range of variables obtained in T1 was entered into the model predicting functional improvement or decline in IADL. Results: Among 1,274 individuals who participated in both T1 and T2, 105 subjects showed improvement, 194 decline, and the remaining 975 showed stability in IADL. Multiple logistic regression analyses indicated that good self-rated health and cognitive function (MMSE ≧24) at T1 were good predictors of both improvement and protection against decline in IADL. Independence in basic activities of daily living predicted improvement in IADL. Advanced age and poor walking ability predicted decline in IADL. Conclusions: Good self-rated health and cognitive function predicted both improvement and protection against decline in IADL. Thus, intervention programs aiming at maintaining both good self-rated health and cognitive function should be able to improve IADL.

Immunoprotective effects of oral intake of heat-killed Lactobacillus pentosus strain b240 in elderly adults: a randomised, double-blind, placebo-controlled trial

Oral intake of Lactobacillus pentosus strain b240 (b240) has been shown to enhance the secretion of salivary secretory IgA in elderly adults. However, its clinical benefits remain to be determined. We tested the hypothesis that b240 exerts a protective effect against the common cold in elderly adults. The design of the present study was a randomised, double-blind, placebo-controlled trial (RCT) with parallel three-group comparison. For this purpose, 300 eligible elderly adults were randomly allocated to one of three groups, namely a placebo, low-dose or high-dose b240 group. Participants in the low-dose and high-dose b240 groups were given tablets containing 2 × 10(9) or 2 × 10(10) cells, respectively, of heat-killed b240, while those in the placebo group were given tablets without b240. Each group consumed their respective tablets once daily for 20 weeks. The common cold was assessed on the basis of a diary. Change in quality of life was evaluated using the SF-36. Of the total participants, 280 completed the 20-week RCT. The accumulated incidence rate of the common cold was 47·3, 34·8 and 29·0 % for the placebo, low-dose b240 and high-dose b240 groups, respectively (P for trend = 0·012). Lower incidence rates were consistently observed throughout the experimental period in the b240 groups (log-rank test, P= 0·034). General health perception, as determined by the SF-36®, dose-dependently increased in the b240 groups ( P <0·025). In conclusion, oral intake of b240 significantly reduced the incidence rate of the common cold in elderly adults, indicating that b240 might be useful in improving resistance against infection through mucosal immunity.

Intellectual activity and likelihood of subsequently improving or maintaining instrumental activities of daily living functioning in community‐dwelling older Japanese: a longitudinal study

To test the a priori hypothesis that increase or maintenance of the level of cognitive activity would be independently associated with a subsequent beneficial impact (i.e. improvement or maintenance) on instrumental activity of daily living (IADL) functioning.

Trajectories of alcohol consumption among older Japanese followed from 1987-1999

This study examined the longitudinal changes in alcohol consumption among elderly Japanese, characterized the subtrajectories within the aggregate trend, and examined potential predictors of these trajectories. Data come from a nationally representative survey of 2,566 persons in Japan, ages 60 to 96, followed over five waves between 1987—1999. Hierarchical linear modeling and cluster analysis were used to uncover trajectories of alcohol use. Multinomial logistic regression was employed to examine the predictors of trajectory association at baseline. Alcohol use appears relatively stable between ages 60 and 70, but declines thereafter. Further, there are three subtrajectories: stable, declining, and curvilinear (in addition to abstainers). Predictors of these trajectories varied by trajectory. Alcohol use may continue to be an important part of life at older ages. However, older drinkers appear to follow four drinking trajectories. Demographic characteristics and stressors may be associated with these trajectories. Knowledge of these trajectories may aid in targeting of interventions.

Work, Health, and Family at Older Ages in Japan:

The authors investigated ways in which the relationship between health and labor force exit at older ages is moderated by family characteristics. Using two waves of data from a national sample of older Japanese men collected in 1999 and 2002, the authors estimated logistic regression models for labor force exit beyond age 63 as a function of health change, family characteristics, and their interactions. Poor health was strongly associated with labor force exit and evidence showed that moderating influences of family context depend on the level of health. However, the results were only partially consistent with hypotheses that the relationship between health and the likelihood of labor force exit should be stronger for (1) those with good health and family incentives to exit the labor force and (2) those with poor health and family incentives to remain in the labor force.

A Descriptive Analysis of Religious Involvement Among Older Adults In Japan.

ABSTRACT The purpose of this study was to conduct a descriptive analysis of multiple dimensions of religious belief and practice among older people in Japan with data from a nationwide sample. Six dimensions were evaluated: religious affiliation, involvement in formal religious organisations, private religious practices, the functions of prayer, belief in punishment by supernatural forces, and beliefs about the afterlife. In addition to describing these dimensions for the sample as a whole, tests were performed to see if they varied by age, sex, marital status, education and for those living in rural or urban areas. The findings suggest that even though older people in Japan are not highly involved in formal religious institutions, they engage frequently in private religious practices, and that while many older people in Japan do not endorse some religious beliefs (e.g. about the quality of the afterlife), there is strong adherence to others (e.g. beliefs about punishment by supernatural forces). It was found that older women are more deeply involved in religion than older men, and that levels of religious involvement appear to be higher in rural than in urban areas. Less pronounced differences were found with respect to age, but compared to the ‘young-old’, the ‘oldest-old’ aged 75 or more years were more deeply involved in those aspects of religion that take place outside formal institutions.