Assessing competence at a higher level among older adults: development of the Japan Science and Technology Agency Index of Competence (JST-IC).

BACKGROUND AND AIMS: Older adults' ever-improving health and changing lifestyles necessitate the development of a scale that can better measure their competence at a higher level. We developed the Japan Science and Technology Agency Index of Competence (JST-IC) via item analysis and assessed its psychometric properties. METHODS: Participants were 1306 community-dwelling older adults (623 men and 683 women, 74.0 ± 2.8 years old) who completed the 54-item draft JST-IC to determine their level of independence. Three procedures (including item selection, factor analyses, and reliability and validity analyses) were conducted to finalize the JST-IC and evaluate its psychometric properties. RESULTS: The item selection resulted in exclusion of 26 items for the following reasons: (a) 15 because of very high ratios (80% or more) of responders who answered "yes", (b) one because of gender differences (phi coefficient = 0.34), (c) five because of their weak association with the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) (Pearson correlation coefficient of 0.30 or smaller), and (d) five because of redundancy of meaning with other items. Through factor analyses, we selected 16 items with a four-factor solution for the final version. JST-IC score exhibited a near-normal distribution and significant gender and age differences, and had moderate correlations with size of social network and level of subjective well-being and strong correlations with TMIG-IC score, physical fitness, and health literacy. CONCLUSIONS: The JST-IC is useful for assessing competence at a higher level in community-dwelling older adults.

Physical and psychological characteristics of the community-dwelling elderly with heart disease.

Objectives Although the survival rates of patients with heart diseases, such as myocardial infarction and heart failure, have increased, the incidence of heart disease in elderly individuals has also increased. We compared characteristics of the community-dwelling elderly with heart diseases (heart disease group) and without heart diseases (non-heart disease group).Methods A total of 758 elderly individuals participated in our survey ("Otassha-kensin") in 2014. The heart disease group (47 men, 28 women) and the non-heart disease group (263 men, 420 women) were selected from among these participants. Data on comorbidities, medications, the Kihon check list (KCL), and social background (lifestyle, exercise habits, certification for using long-term care insurance, and Japan Science and Technology Agency Index of Competence [JST-IC]) were obtained through interview. Body composition, grip strength, 5 walking time (usual pace, maximum speed), timed-up and go test (TUG), single-leg standing time, cognitive function, and depression were evaluated to assess physical and psychological function. Frailty was defined by the KCL. For between-groups comparisons, the Student t-test and Mann-Whitney U-test were used. To determine factors related to heart disease with functional decline, we used a multiple logistic regression analysis with the group (the non-heart disease group [0] and the heart disease group [1]) as the dependent variable and the decline in physical and psychological function as the independent variable.Results Men in the heart disease group had less grip strength, worse balance, and lower JST-IC scores than did men in the non-heart disease group. Women in the heart disease group had greater 5 walking times (usual pace, maximum speed) than those in the non-heart disease group. Both men and women in the heart disease group overall used more drugs and statins, and medications for heart disease than did participants in the non-heart disease group. In the multiple logistic regression analysis, 5 walking time (maximum speed) was shown to be associated with heart disease.Conclusions The community-dwelling elderly with heart disease showed declined physical functions. Our results suggested that these functional declines may be induced via medication and/or declines in daily activity.

Can You Ride a Bicycle? The Ability to Ride a Bicycle Prevents Reduced Social Function in Older Adults With Mobility Limitation.

BACKGROUND: The health benefits of bicycling in older adults with mobility limitation (ML) are unclear. We investigated ML and functional capacity of older cyclists by evaluating their instrumental activities of daily living (IADL), intellectual activity, and social function. METHODS: On the basis of interviews, 614 community-dwelling older adults (after excluding 63 participants who never cycled) were classified as cyclists with ML, cyclists without ML, non-cyclists with ML (who ceased bicycling due to physical difficulties), or non-cyclists without ML (who ceased bicycling for other reasons). A cyclist was defined as a person who cycled at least a few times per month, and ML was defined as difficulty walking 1 km or climbing stairs without using a handrail. Functional capacity and physical ability were evaluated by standardized tests. RESULTS: Regular cycling was documented in 399 participants, and 74 of them (18.5%) had ML; among non-cyclists, 49 had ML, and 166 did not. Logistic regression analysis for evaluating the relationship between bicycling and functional capacity revealed that non-cyclists with ML were more likely to have reduced IADL and social function compared to cyclists with ML. However, logistic regression analysis also revealed that the risk of bicycle-related falls was significantly associated with ML among older cyclists. CONCLUSIONS: The ability and opportunity to bicycle may prevent reduced IADL and social function in older adults with ML, although older adults with ML have a higher risk of falls during bicycling. It is important to develop a safe environment for bicycling for older adults.

Prevalence and factors associated with xerostomia and hyposalivation among community-dwelling older people in Japan.

OBJECTIVE: This study investigated the prevalence and factors associated with xerostomia and hyposalivation among community-dwelling older people. BACKGROUND: Xerostomia and hyposalivation are common symptoms in the older population. MATERIALS AND METHODS: This study included with 894 community-dwelling, Japanese older people (355 men, 539 women; age 65-84 years) who participated in a comprehensive geriatric health examination, which included questionnaires and interviews regarding medical history, medications, Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC), depressive condition. The Zung Self-Rating Depression Scale (SDS) was used to evaluate depression. Resting salivary flow rate was evaluated by the modified cotton roll method. RESULTS: In this study, 34.8% of the participants (mean age, 73.5 ± 5.0 years) complained about xerostomia, while the prevalence of hyposalivation was 11.5%. Multiple regression analysis revealed hypnotics use [odds ratio (OR) = 1.71, 95% confidence interval (CI) = 1.13-2.61], SDS (OR = 1.05, CI = 1.04-1.07) and TMIG-IC total points (OR = 0.87, CI = 0.76-0.99) to be significantly associated with xerostomia. In contrast, female gender (OR = 2.59, CI = 1.55-4.31) and the use of agents affecting digestive organs (OR = 1.78, CI = 1.11-2.86) were associated with hyposalivation. CONCLUSION: Our findings showed that the prevalence of xerostomia and hyposalivation were approximately 1 in 3 and 1 in 10 respectively. The factors associated with psychological factors and high-level functional competence, while hyposalivation was associated with medications and gender, as well as systemic and/or metabolic differences. It is important to consider these multidimensional factors associated with xerostomia and hyposalivation.

Association between the nutritional status and the severity of sarcopenia among community-dwelling elderly Japanese people.

AIM: To investigate the association between nutritional evaluation indices (body mass index, albumin, and weight loss) and sarcopenia severity among community-dwelling elderly people in Japan. METHODS: The subjects consisted of 758 community-dwelling elderly people ≥65 years of age, categorized into two groups by based on Operation of long life medical care system (medical care system for elderly in the latter stage of life), the cut-off value for age used was 75. The outcome measures were basic characteristics, anthropometric measures, physical function, and blood biochemistry (five assessments). The appendicular skeletal muscle mass was calculated via a bioelectrical impedance analysis. The subjects were categorized into three groups by the body mass index (BMI) [BMI 3 group]. The cut-off value for albumin used was 3.8 g/dL [A1b 2 group]. Weight loss was assessed using item 11 on the Kihon check list: "Have you experienced more than 2-3 kg weight loss over the past 6 months? Yes=1, No=0." [weight loss 2 group]. Sarcopenia was defined based on the European Working Group on Sarcopenia in Older People definition, using the Asian Working Group for Sarcopenia cut-off values. All subjects were then categorized into four groups based on their sarcopenia status: non-sarcopenic (non-), pre-sarcopenic (pre-), sarcopenic (sarco-), or severely sarcopenic (severe-) [sarco4 group]. RESULTS: The prevalence of sarcopenia and severe sarcopenia in men was 5.6% (n=18) and 1.2% (n=4), respectively, and in women was 7.8% (n=34) and 1.6% (n=7), respectively. The analysis showed that, among the people (>75 years of age) with normal BMI (18.5-25.0), 10.4%-15.6% were in the Sarco group. Further, among women over 75 years of age with BMI >25.0, 5.7% (n=2) were in the Sarco group. There was a significant association between weight loss and sarcopenia severity in older men. No significant association between albumin levels and sarcopenia severity was observed. 80.0% of weight-loss was presented in above BMI 18.5 kg/m2 and Alb 3.8 g/dL. CONCLUSION: Sarcopenia and severe sarcopenia were prevalent among those with normal BMI, and particularly among obese women over 75 years of age. Weight-loss was presented in above BMI 18.5 kg/m2 and Alb 3.8 g/dL. Our findings indicate that the nutritional evaluation indices, including BMI, albumin, and weight loss, were insufficient in screening for malnutrition and sarcopenia among the elderly.

Incidence of disability and its associated factors in Japanese men and women: the Longitudinal Cohorts of Motor System Organ (LOCOMO) study.

We investigated the incidence of disability and its risk factors in older Japanese adults to establish an evidence-based disability prevention strategy for this population. For this purpose, we used data from the Longitudinal Cohorts of Motor System Organ (LOCOMO) study, initiated in 2008 to integrate information from cohorts in nine communities across Japan: Tokyo (two regions), Wakayama (two regions), Hiroshima, Niigata, Mie, Akita, and Gunma prefectures. We examined the annual occurrence of disability from 8,454 individuals (2,705 men and 5,749 women) aged ≥65 years. The estimated incidence of disability was 3.58/100 person-years (p-y) (men: 3.17/100 p-y; women: 3.78/100 p-y). To determine factors associated with disability, Cox's proportional hazard model was used, with the occurrence of disability as an objective variable and age (+1 year), gender (vs. women), body build (0: normal/overweight range, BMI 18.5-27.5 kg/m(2); 1: emaciation, BMI <18.5 kg/m(2); 2: obesity, BMI >27.5 kg/m(2)), and regional differences (0: rural areas including Wakayama, Niigata, Mie, Akita, and Gunma vs. 1: urban areas including Tokyo and Hiroshima) as explanatory variables. Age, body build, and regional difference significantly influenced the occurrence of disability (age, +1 year: hazard ratio 1.13, 95% confidence interval 1.12-1.15, p < 0.001; body build, vs. emaciation: 1.24, 1.01-1.53, p = 0.041; body build, vs. obesity: 1.36, 1.08-1.71, p = 0.009; residence, vs. living in rural areas: 1.59, 1.37-1.85, p < 0.001). We concluded that higher age, both emaciation and obesity, and living in rural areas would be risk factors for the occurrence of disability.

Association between self-reported urinary incontinence and musculoskeletal conditions in community-dwelling elderly women: a cross-sectional study.

AIMS: Urinary incontinence (UI) and musculoskeletal conditions, particularly low back pain (LBP), and osteoarthritis (OA), are common problems that have been associated with mobility limitations and future dependence in activities of daily living in the elderly. The purpose of this study was to explore the relationship between UI, UI types, and musculoskeletal conditions in elderly community-dwelling women. METHODS: A cross-sectional study was performed on 1,399 community-dwelling Japanese women aged 75-84 years. Face-to-face interviews, body composition, and physical function, including grip strength, and usual walking speed, were conducted. UI was defined as experience of urine leakage episodes more than once per week. Self-reported presence and degree of pain, LBP, and OA were assessed. Student's t-tests and chi-square tests were used to analyze continuous and categorical variables. Associations between selected variables, UI, and UI types were assessed using stepwise multiple logistic regression models. RESULTS: A total of 260 participants had UI (18.6%) and 399 had LBP (28.5%). Participants with UI were more likely to experience pain (76.0%) and LBP (36.2%) than those without UI (P < 0.001 and P = 0.002, respectively). Age, body mass index, falls, walking speed, grip strength, LBP, and pain coupled with OA were significantly associated with UI. There were significant associations between urge UI and mild (odds ratio (OR) = 1.653, 95% confidence interval (CI) = 1.031-2.650) and severe LBP (OR = 2.617, 95% CI = 1.193-5.739). CONCLUSIONS: This study showed that UI was significantly associated with musculoskeletal conditions, including LBP, and the combination of pain and OA. The risk of urge UI was greater with increasing severity of LBP.

Longitudinal association between habitual physical activity and depressive symptoms in older people.

AIMS: Prevention of depressive symptoms is an essential issue with regard to the promotion of healthy lifestyles in older people. To date, few studies have examined the relation between fluctuations in physical activity and depression among older individuals. We thus conducted a longitudinal survey of older adults to examine the effect of long-term fluctuating physical activity on the incidence of depressive symptoms. METHODS: A 3-year prospective cohort study was performed in a community-based environment. A total of 680 individuals (291 men and 389 women) aged 65 years and over at the baseline assessment participated. The 15-item Geriatric Depression Scale was used to assess depressive symptoms, with scores of ≥6 indicative of depression. Participants were categorized into the following four groups based on change in physical activity status between 2002 and 2003: sedentary, cessation, initiation, and maintenance. RESULTS: The incidence of depressive symptoms was 16.9% (16.8% in men and 17.0% in women) at the 3-year follow up (in 2006). Multiple logistic regression analyses showed that physical activity maintenance (odds ratio, 0.50; 95% confidence interval, 0.30-0.83) only reduced the incidence of depressive symptoms at the 3-year follow up after adjusting for confounding variables. CONCLUSIONS: Continuous physical activity may be a valuable and simple way to prevent depressive symptoms in community-dwelling older people. Therefore, it is necessary to implement interventions that teach older adults how to integrate physical activity into their daily lives.

[Incidence of bicycle-related accidents and subsequent injury in community-dwelling older adults: understanding potential accidents].

OBJECTIVES: This study investigated 1) the incidence of bicycle-related accidents and subsequent injuries and 2) the number of injuries (accidents) reported to the police (i.e., examining the number of potential accidents) among community-dwelling Japanese older adults, after examining the percentage of those who were regular cyclists. METHODS: Based on local resident registration, we mailed questionnaires to 7083 community-dwelling older adults. The questionnaire included questions about the incidence of bicycle-related accidents and subsequent injury within a year, the degree of injury and presence or absence of reporting that injury (bicycle-related accident) to the police. For the bicycle-related accident, we asked regarding both riding and pedestrian accidents (i.e., accidents caused by a bicycle when walking). RESULTS: Excluding the blank responses (n=3539, 50.0%), the targets for analysis were 3098 older adults in riding accidents and 2861 older adults in pedestrian accidents. The results showed that 63.0% of older adults (n=1953) routinely rode a bicycle. Among them, 9.4% (n=184) experienced riding accidents, and 3.4% (n=98) experienced pedestrian accidents caused by a bicycle. For the riding accidents, 76.1% (n=140) had some injuries, and for the pedestrian accidents, 55.1% (n=54) had some injuries. Furthermore, in 70.2% (n=59) and 76.9% (n=20) of riding and pedestrian accidents, respectively, those who went to the hospital for treatment of their injury (i.e., injury requiring treatment) did not report the accident to the police. CONCLUSION: The present study revealed that there are many potential bicycle-related accidents in older adults. This suggests that there may be a large gap in the national survey data between reported bicycle-related accidents and the actual number of incidents in older adults.

Prevalence of knee pain, lumbar pain and its coexistence in Japanese men and women: The Longitudinal Cohorts of Motor System Organ (LOCOMO) study.

The Longitudinal Cohorts of Motor System Organ (LOCOMO) study was initiated in 2008 through a grant from the Ministry of Health, Labour, and Welfare of Japan to integrate information from several cohorts established for the prevention of musculoskeletal diseases. We integrated the information of 12,019 participants (3,959 men and 8,060 women) in the cohorts comprising nine communities located in Tokyo (two regions: Tokyo-1 and Tokyo-2), Wakayama [two regions: Wakayama-1 (mountainous region) and Wakayama-2 (seaside region)], Hiroshima, Niigata, Mie, Akita, and Gunma prefectures. The baseline examination of the LOCOMO study consisted of an interviewer-administered questionnaire, anthropometric measurements, medical information recording, X-ray radiography, and bone mineral density measurement. The prevalence of knee pain was 32.7 % (men 27.9 %; women 35.1 %) and that of lumbar pain was 37.7 % (men 34.2 %; women 39.4 %). Among the 9,046 individuals who were surveyed on both knee pain and lumbar pain at the baseline examination in each cohort, we noted that the prevalence of both knee pain and lumbar pain was 12.2 % (men 10.9 %; women 12.8 %). Logistic regression analysis showed that higher age, female sex, higher body mass index (BMI), living in a rural area, and the presence of lumbar pain significantly influenced the presence of knee pain. Similarly, higher age, female sex, higher BMI, living in a rural area, and the presence of knee pain significantly influenced the presence of lumbar pain. Thus, by using the data of the LOCOMO study, we clarified the prevalence of knee pain and lumbar pain, their coexistence, and their associated factors.

Information processing speed and 8-year mortality among community-dwelling elderly Japanese.

BACKGROUND: Cognitive function is an important contributor to health among elderly adults. One reliable measure of cognitive functioning is information processing speed, which can predict incident dementia and is longitudinally related to the incidence of functional dependence. Few studies have examined the association between information processing speed and mortality. This 8-year prospective cohort study design with mortality surveillance examined the longitudinal relationship between information processing speed and all-cause mortality among community-dwelling elderly Japanese. METHODS: A total of 440 men and 371 women aged 70 years or older participated in this study. The Digit Symbol Substitution Test (DSST) was used to assess information processing speed. DSST score was used as an independent variable, and age, sex, education level, depressive symptoms, chronic disease, sensory deficit, instrumental activities of daily living, walking speed, and cognitive impairment were used as covariates. RESULTS: During the follow-up period, 182 participants (133 men and 49 women) died. A multivariate Cox proportional hazards model showed that lower DSST score was associated with increased risk of mortality (hazard ratio [HR] = 1.62, 95% CI = 0.97-2.72; HR = 1.73, 95% CI = 1.05-2.87; and HR = 2.55, 95% CI = 1.51-4.29, for the third, second, and first quartiles of DSST score, respectively). CONCLUSIONS: Slower information processing speed was associated with shorter survival among elderly Japanese.

Association of physical activities of daily living with the incidence of certified need of care in the long-term care insurance system of Japan: the ROAD study.

BACKGROUND: The present study aimed to investigate association of physical activities of daily living with the incidence of certified need of care in the national long-term care insurance (LTCI) system in elderly Japanese population-based cohorts. METHODS: Of the 3,040 participants in the baseline examination, we enrolled 1,773 (699 men, 1,074 women) aged 65 years or older who were not certified as in need of care-level elderly at baseline. Participants were followed during an average of 4.0 years for incident certification of need of care in the LTCI system. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used assess function. Associated factors in the baseline examination with the occurrence were determined by multivariate Cox proportional hazards regression analysis. Receiver operating characteristic curve analysis was performed to evaluate cut-off values for discriminating between the occurrence and the non-occurrence group. RESULTS: All 17 items in the WOMAC function domain were significantly associated with the occurrence of certified need of care in the overall population. Cut-off values of the WOMAC function score that maximized the sum of sensitivity and specificity were around 4-6 in the overall population, in men, and in women. Multivariate Cox hazards regression analysis revealed that a WOMAC function score ≥4 was significantly associated with occurrence with the highest hazard ratio (HR) for occurrence after adjusting for confounders in the overall population (HR [95 % confidence interval (CI)] 2.54 [1.76-3.67]) and in women [HR (95 % CI) 3.13 (1.95-5.02)]. A WOMAC function score ≥5 was significantly associated with the highest HR for occurrence in men [HR (95 % CI) 1.88 (1.03-3.43)]. CONCLUSIONS: Physical dysfunction in daily living is a predictor of the occurrence of certified need of care. Elderly men with a WOMAC function score ≥5 and women with a score ≥4 should undergo early intervention programs to prevent subsequent deterioration.

Physical and sociopsychological characteristics of older community residents with mild cognitive impairment as assessed by the Japanese version of the Montreal Cognitive Assessment.

BACKGROUND: Although mild cognitive impairment (MCI) criteria are disputable, characterizing various aspects of operational MCI (O-MCI) may lead to a better understanding of potential modulators of cognitive decline and contribute to more effective public health strategies. The aim of the study is to examine characteristics of community-dwelling elderly people with MCI assessed using Japanese version of Montreal Cognitive Assessment (MoCA-J). METHODS: A total of 913 community-dwelling Japanese (65-84 years) participated in health examinations in Tokyo, 2011. The MoCA-J, Mini-Mental State Examination (MMSE), and other physical and mental tests were conducted. Excluded were those with <24 MMSE scores. Those with <26 in MoCA-J were divided into 2 subgroups, (A) participants independent of instrumental activities of daily living (IADL) and no memory complaints and (B) participants independent of IADL with memory complaints or partially dependent on IADL with/without memory complaints. Those with ≥26 in MoCA-J and subgroup (A) of MCI were the normal controls (NCs, 57.4%), and subgroup (B) of MCI was O-MCI, 36.5%. We compared each variable between NC and O-MCI, using logistic regression analysis, adjusted for gender and age. RESULTS: The majority of all the groups were independent of IADL. The O-MCI characteristics were increased depressive symptom, worse self-rated health, lower systolic blood pressure, poorer intellectual activities, no hobbies, weaker grip strength, and slower than usual walking speed compared to the NC group. CONCLUSIONS: Older persons with O-MCI defined by MoCA-J have partially decreased cognition and physical and sociopsychological functions.

Global cognition and 8-year survival among Japanese community-dwelling older adults.

OBJECTIVE: We sought to examine the longitudinal relationship between cognitive function and all-cause mortality among Japanese community-dwelling older adults, using an 8-year prospective cohort study design with mortality surveillance. METHODS: A total of 454 men and 386 women, aged 70 years and older, participated in the study. The Mini Mental State Examination (MMSE) was administered to assess global cognition. The total MMSE score and subscale scores were used as independent variables, and age, gender, education level, chronic disease, sensory deficit, depressive symptoms, and instrumental activities of daily living were used as covariates. RESULTS: During the follow-up period, 191 subjects (139 men and 52 women) died, and 64 subjects (31 men and 33 women) moved to a different region of Japan and were lost to follow-up. Use of the multivariate Cox proportional hazards model, adjusted for potential confounders, showed that global cognition was significantly and independently associated with mortality (hazard ratio [HR] = 1.59, 95% confidence interval [CI]: 1.14-2.23 and HR = 2.81, 95% CI: 1.77-4.36 for the middle [24-27 points] and lowest [0-23 points] categories, respectively). Among the MMSE subscales, place orientation (HR = 1.57, 95% CI: 1.09-2.25), calculation (HR = 1.67, 95% CI: 1.18-2.35), and delayed recall (HR = 1.42, 95% CI: 1.03-1.96), were also significantly and independently associated with mortality. CONCLUSIONS: Our study suggests that among older individuals, those with lower levels of cognitive function are more likely to have a shorter lifespan compared with those with higher cognitive functioning.

[Are gait parameters related to knee pain, urinary incontinence and a history of falls in community-dwelling elderly women?].

AIM: To examine the association between gait parameters and knee pain, urinary incontinence, and a history of falls. METHODS: Comprehensive health examinations were conducted in 2009 among 971 elderly women over 70 years of age, in which the questionnaire and gait parameter results of 870 participants were analyzed. Knee pain, urinary incontinence and a history of falls were assessed through face-to-face interview surveys. Gait parameters were measured using a walk-way to assess walking speed, cadence, stride, stride length, step width, walking angle, toe angle and the differences in each parameter between the right and left foot. Multiple logistic regression analyses were performed to examine the associations between the gait parameters and knee pain, urinary incontinence and a history of falls. RESULTS: The elderly women with knee pain, urinary incontinence and a history of falls had slower walking speeds, smaller strides and strides length, and wider step width and walking angles. The multiple logistic regression analysis showed the walking speed to be significantly associated with mild knee pain and urinary incontinence and single a history of fall; moderate/severe knee pain was significantly associated with step width (OR=0.58, 95%CI=0.40-0.84) and walking angle (OR=1.62, 95%CI=1.30-2.01); moderate/severe urinary incontinence was significantly associated with walking speed (OR=0.97, 95%CI=0.96-0.99), walking angle (OR=1.14, 95%CI=1.02-1.26), and difference in walking angle between the right and left foot (OR=1.43, 95%CI=1.09-1.86); multiple a history of falls was significantly associated with stride length (OR=0.85, 95%CI=0.79-0.93) and the difference in walking angle between the right and left foot (OR=1.36, 95%CI=1.01-1.85). CONCLUSIONS: The data suggest that combining assessments of walking speed and other gait parameters may be an effective screening method for the early detection of geriatric syndromes.

Independent association of joint space narrowing and osteophyte formation at the knee with health-related quality of life in Japan: a cross-sectional study.

OBJECTIVE: To clarify the individual associations of joint space narrowing (JSN) and osteophytosis at the knee with quality of life (QOL) in Japanese men and women using a large-scale population-based cohort from the Research on Osteoarthritis Against Disability (ROAD) study. METHODS: The associations of minimum joint space width (JSW) and osteophyte area in the medial compartment of the knee with QOL parameters, such as the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), were examined. Minimum JSW and osteophyte area in the medial compartment of the knee were measured using a computer-aided system for the diagnosis of knee osteoarthritis. RESULTS: Of the 3,040 participants in the ROAD study, the present study included 2,039 participants age 40 years or older who completed the questionnaires (741 men and 1,298 women with a mean ± SD age of 68.6 ± 10.9 years). Multiple regression analysis after adjustment for age and body mass index showed that minimum JSW was significantly associated with scores on the pain domains of the WOMAC in men and women, while osteophyte area was significantly associated with scores on the physical function domains of the WOMAC in men and women. CONCLUSION: The findings of this cross-sectional study using a large-scale population from the ROAD study indicate that JSN and osteophytosis are independently associated with QOL.

Development of a glutathione production process from proteinaceous biomass resources using protease-displaying Saccharomyces cerevisiae.

Glutathione is a valuable tri-peptide that is widely used in the pharmaceutical, food, and cosmetic industries. Glutathione is produced industrially by fermentation using Saccharomyces cerevisiae, and supplementation of fermentation with several amino acids can increase intracellular GSH content. More recently, however, focus has been given to protein as a resource for biofuel and fine chemical production. We demonstrate that expression of a protease on the cell surface of S. cerevisiae enables the direct use of keratin and soy protein as a source of amino acids and that these substrates enhanced intracellular GSH content. Furthermore, fermentation using soy protein also enhanced cell concentration. GSH fermentation from keratin and to a greater extent from soy protein using protease-displaying yeast yielded greater GSH productivity compared to GSH fermentation with amino acid supplementation. This protease-displaying yeast is potentially applicable to a variety of processes for the bio-production of value-added chemicals from proteinaceous biomass resources.

Declines in physical performance by sex and age among nondisabled community-dwelling older Japanese during a 6-year period.

BACKGROUND: Few studies have examined whether declines over time in hand-grip strength (HGS) and fast walking speed (FWS) differ by sex and age among non-Western community-dwelling older adults. This study aimed to quantify changes in HGS and FWS over the 6-year period from 1994 to 2000 and examine whether these changes differed by sex and baseline age among older individuals in a Japanese community. METHODS: We conducted a community-based prospective cohort study. The participants were 513 nondisabled men and women aged 67 to 91 years at the 1994 survey. Independent variables regarding time since baseline, in addition to various time-dependent and time-independent covariates, were obtained in 1994, 1996, 1998, and 2000. The outcome variables were HGS and FWS assessed at each survey. All data on independent and dependent variables that were collected at each survey were simultaneously analyzed using a linear mixed-effects model. RESULTS: The linear mixed-effects model revealed significant declines in both HGS (-0.70 kg/year, P < 0.001) and FWS (-0.027 m/sec/year, P < 0.001) among nondisabled older participants who had analyzable data in any survey during the 6-year period. Sex was significantly associated with the rate of decline in HGS (P < 0.001), but not FWS (P = 0.211). CONCLUSIONS: In this analysis of nondisabled older Japanese, a mixed-effects model confirmed a significant effect of aging on declines in HGS and FWS and showed that men had a significantly steeper decline in HGS than did women during a 6-year period.

Efficient and direct glutathione production from raw starch using engineered Saccharomyces cerevisiae.

Glutathione is a valuable tri-peptide that is widely used in the pharmaceutical, food, and cosmetic industries. Glutathione is produced industrially by fermentation using Saccharomyces cerevisiae. We demonstrated that expression of amylase genes in glutathione-producing S. cerevisiae enables direct use of starch as a carbon source, thus eliminating the Crabtree effect that is caused by excess glucose. Consequently, cell growth and glutathione productivity were significantly improved. This approach is potentially applicable to a variety of fermentative processes for production of value-added chemicals under aerobic conditions.

Enzymatic glutathione production using metabolically engineered Saccharomyces cerevisiae as a whole-cell biocatalyst.

We developed a novel enzymatic glutathione (GSH) production system using Saccharomyces cerevisiae as a whole-cell biocatalyst, and improved its GSH productivity by metabolic engineering. We demonstrated that the metabolic engineering of GSH pathway and ATP regeneration can significantly improve GSH productivity by up to 1.7-fold higher compared with the parental strain, respectively. Furthermore, the combination of both improvements in GSH pathway and ATP regeneration is more effective (2.6-fold) than either improvement individually for GSH enzymatic production using yeast. The improved whole-cell biocatalyst indicates its great potential for applications to other kinds of ATP-dependent bioproduction.