Association of the interaction between physical activity and sitting time with mortality in older Japanese adults

Oral frailty is associated with mortality independently of physical and psychological frailty among older adults

BACKGROUND

Although oral frailty is independently associated with an increased risk of mortality, evidence for the usefulness of screening tools for oral frailty is less than that for physical frailty screening tools. We aimed to investigate the relationship between oral frailty and mortality in older adults.

METHODS

This prospective cohort study included 11,374 adults aged ≥65 years, who provided valid responses to a baseline mail survey questionnaire from the Kyoto-Kameoka study. Oral frailty status was evaluated using the Oral Frailty Index-8 (range, 0 [best] to 10 [worst]). Participants were classified into four categories according to the Oral Frailty Index-8: robust (score, 0-2), oral pre-frailty (score, 3), oral frailty (score, 4-6), and oral severe frailty (score ≥ 7). Physical and psychological frailty were evaluated using the validated frailty-screening index and defined as a score of ≥3 out of a possible 5 points. Mortality data were collected from 30 July 2011 to 30 November 2016. Hazard ratios (HR) for all-cause mortality were calculated using a multivariable Cox proportional hazards model.

RESULTS

During the 5.3-year median follow-up period (57,157 person-years), 1184 deaths were recorded. After adjusting for confounders, including physical and psychological frailty, medical history, and lifestyle, in comparison with a robust oral status, oral pre-frailty (HR, 1.29; 95 % confidence interval [CI], 1.02-1.63), oral frailty (HR, 1.22; 95 % CI, 1.01-1.48), and oral severe frailty (HR, 1.43; 95 % CI, 1.16-1.76) were associated with higher HRs of mortality (p for trend = 0.002).

CONCLUSION

Oral frailty is associated with mortality independent of physical and psychological frailty in older adults. The Oral Frailty Index-8 may be useful for identifying individuals at high risk of mortality.

Effects of physical activity and sedentary behaviors on cardiovascular disease and the risk of all-cause mortality in overweight or obese middle-aged and older adults

Aim

The aim of this study was to respectively explore the relationships between physical activity and sedentary behaviors and cardiovascular disease (CVD) and all-cause mortality risk in overweight/obese middle-aged and older patients, and also assess the interaction between physical activity and sedentary behaviors.

Methods

Data of middle-aged and older adults with body mass index (BMI) ≥25 kg/m2 were extracted from the National Health and Nutrition Examination Surveys (NHANES) database in 2007-2018 in this retrospective cohort study. Weighted univariate and multivariate logistic regression analyses were used to explore the associations between physical activity and sedentary behaviors and CVDs; weighted univariate and multivariate Cox regression analyses were used to explore the relationships between physical activity and sedentary behaviors with the risk of all-cause mortality. The interaction effect between physical activity and sedentary behaviors on CVD and all-cause mortality was also assessed. We further explored this interaction effect in subgroups of age and BMI. The evaluation indexes were odds ratios (ORs), hazard ratios (HRs), and 95% confidence intervals (CIs).

Results

Among 13,699 eligible patients, 1,947 had CVD, and 1,560 died from all-cause mortality. After adjusting for covariates, patients who had high sedentary time seemed to have both high odds of CVD [OR = 1.24, 95% CI: (1.06-1.44)] and a high risk of all-cause mortality [HR = 1.20, 95% CI: (1.06-1.37)]. Furthermore, being insufficiently active was linked to high odds of CVD [OR = 1.24, 95% CI: (1.05-1.46)] as well as a high risk of all-cause mortality [HR = 1.32, 95% CI: (1.15-1.51)]. High sedentary time and being insufficiently active had an interaction effect on both high odds of CVD [OR = 1.44, 95% CI: (1.20-1.73)] and high risk of all-cause mortality [HR = 1.48, 95% CI: (1.24-1.76)]. Individuals of different ages with/without obesity need to focus on the potential CVD/mortality risk of high sedentary time and low physical activity (all P < 0.05).

Conclusion

Reducing sedentary time combined with increasing physical activity may benefit health by reducing both the risk of CVD and all-cause mortality in overweight or obese middle-aged and older adults.

Association between doubly labelled water-calibrated energy intake and objectively measured physical activity with mortality risk in older adults

BACKGROUND

Physical activity or biomarker-calibrated energy intake (EI) alone is associated with mortality in older adults; the interaction relationship between the combined use of both factors and mortality has not been examined. We evaluated the relationship between mortality and calibrated EI and step counts in older adults.

METHODS

This prospective study included 4,159 adults aged ≥65 years who participated in the Kyoto-Kameoka study in Japan and wore a triaxial accelerometer between 1 April and 15 November 2013. The calibrated EI was calculated based on a previously developed equation using EI biomarkers. The step count was obtained from the accelerometer ≥ 4 days. Participants were classified into the following four groups: low EI (LEI)/low step counts (LSC) group (EI: <2,400 kcal/day in men and <1,900 kcal/day in women; steps: <5,000 /day), n = 1,352; high EI (HEI)/LSC group (EI: ≥2,400 kcal/day in men and ≥1,900 kcal/day in women; steps: <5,000 /day), n = 1,586; LEI/high step counts (HSC) group (EI: <2,400 kcal/day in men and < 1,900 kcal/day in women; steps: ≥5,000 /day), n = 471; and HEI/HSC group (EI: ≥2,400 kcal/day in men and ≥1,900 kcal/day in women; steps: ≥5,000 /day), n = 750. Mortality-related data were collected until 30 November 2016. We performed a multivariable Cox proportional hazard analysis.

RESULTS

The median follow-up period was 3.38 years (14,046 person-years), and 111 mortalities were recorded. After adjusting for confounders, the HEI/HSC group had the lowest all-cause mortality rate compared to other groups (LEI/LSC: reference; HEI/LSC: hazard ratio [HR]: 0.71, 95% confidence interval [CI]: 0.41-1.23; LEI/HSC: HR: 0.59, 95% CI: 0.29-1.19; and HEI/HSC: HR: 0.10, 95% CI: 0.01-0.76). No significant interaction was observed between the calibrated EI and steps with mortality. The spline model showed that 35-42 kcal/100 steps/day of EI/100 steps was associated with the lowest mortality risk.

CONCLUSIONS

HR mortality risk was lowest at 35-42 kcal/100 steps/day, suggesting that very high (≥56 kcal) or low (<28 kcal) EI/100 steps are not inversely associated with mortality. Adherence to optimal EI and adequate physical activity may provide sufficient energy balance to explain the inverse association with mortality among older Japanese adults.

Association between excess mortality in depressive status and frailty among older adults: A population-based Kyoto-Kameoka prospective cohort study

OBJECTIVES

Frailty has been shown to be a mediator of the risk of excess death due to depression in older adults, although this relationship has not been sufficiently investigated. Our objective was to evaluate this relationship.

METHODS

We used data from 7,913 Japanese people aged≥65 years who participated in the Kyoto-Kameoka prospective cohort study and who provided valid responses to the Geriatric Depression Scale-15 (GDS-15) and the World Health Organization-Five Well-Being Index (WHO-5) in mail-in surveys. Depressive status was assessed using the GDS-15 and WHO-5. Frailty was evaluated using the Kihon Checklist. Data on mortality were collected from February 15, 2012, to November 30, 2016. We evaluated the relationship between depression and all-cause mortality risk using a Cox proportional-hazards model.

RESULTS

The prevalence of depressive status assessed by GDS-15 and WHO-5 was 25.4% and 40.1%, respectively. In total, 665 deaths were recorded during a median follow-up period of 4.75 years (35,878 person-years). After adjusting for confounders, we found that depressive status assessed by the GDS-15 had a higher risk of mortality than those without it (hazard ratio [HR] 1.62, 95% confidence interval [CI] 1.38-1.91). This association was moderately weaker when adjusted for frailty (HR 1.46, 95% CI 1.23-1.73). Similar results were observed when depression was assessed with the WHO-5.

CONCLUSION

Our findings suggest that the risk of excess death due to depressive status in older adults may be partially explained by frailty. This indicates a need to focus on improving frailty besides conventional depression treatments.

Factors associated with changes in the objectively measured physical activity among Japanese adults: A longitudinal and dynamic panel data analysis

Factors associated with dynamic changes in the objectively measured physical activity have not been well understood. We aimed to 1) evaluate the longitudinal change in the physical activity trajectory according to sex which is associated with age and to 2) determine the factors associated with the dynamic change in physical activity-related variables across a wide age range among Japanese adults. This longitudinal prospective study included 689 Japanese adults (3914 measurements) aged 26-85 years, whose physical activity data in at least two surveys were available. Physical activity-related variables, such as intensity (inactive, light [LPA; 1.5 to 2.9 metabolic equivalents (METs)], moderate-to-vigorous [MVPA; ≥3.0 METs]), total energy expenditure (TEE), physical activity level (PAL), and step count, were evaluated using a validated triaxial accelerometer. Statistical analysis involved the latent growth curve models and random-effect panel data multivariate regression analysis. During a mean follow-up period of 6.8 years, physical activity was assessed an average of 5.1 times in men and 5.9 times in women. The profiles for the inactive time, LPA (only men), MVPA, step count, PAL, and TEE showed clear curvature, indicating an accelerated rate of change around the age of 70. In contrast, other variables exhibited minimal or no curvature over the age span. The MVPA trajectory was positively associated with alcohol consumption, hand grips, leg power, and trunk flexibility and negatively associated with age, local area, body mass index (BMI), comorbidity score, and heart rate over time. Our results indicated that the physical activity trajectory revealed clear curvature, accelerated rate of change around the age of 70, and determined physical health and fitness and BMI as dynamic factors associated with physical activity changes. These findings may be useful to help support populations to achieve and maintain the recommended level of physical activity.

Doubly labelled water-calibrated energy intake associations with mortality risk among older adults

BACKGROUND

The body mass index (BMI) is closely related to mortality risk, and energy intake (EI) is essential for maintaining energy balance in weight control. However, self-reported EI has been shown to lead to a systematic underestimation. Total energy expenditure measured using the doubly labelled water (DLW) method is considered an objective biomarker of EI and the gold standard for its estimation in individuals with stable body weight. We aimed to examine the association between DLW-calibrated EI and BMI on overall mortality risk in older adults.

METHODS

A prospective cohort study was performed using data of 8051 (4267 women and 3784 men) Japanese older adults from the Kyoto-Kameoka Study in Japan. Calibrated EI was calculated from the estimated EI using a food frequency questionnaire and equation developed based on DLW. Participants were classified by quartiles based on their EI stratified by sex. BMI was calculated using self-reported height and body weight. Mortality data were collected between 30 July 2011 and 30 November 2016. Statistical analysis was performed using the multivariable-adjusted Cox proportional hazard model with a restricted cubic spline.

RESULTS

The 8051 participants' mean (standard deviation) age and BMI were 73.5 (6.1) years and 22.6 (3.0) kg/m² , respectively. The mean (standard deviation) EI with and without calibration was 1909 (145) kcal/day and 1569 (358) kcal/day in women and 2383 (160) kcal/day and 1980 (515) kcal/day in men, respectively. During the median 4.75 years of follow-up (36 552 person-years), 661 deaths were recorded. In both women (hazard ratio [HR], 0.63; 95% confidence interval [CI] [0.41, 0.98]) and men (HR, 0.62; 95% CI [0.44, 0.87]), after adjusting for confounders, the top quartile as compared with the bottom calibrated EI quartile showed a negative association with risk of all-cause mortality. The lowest HR for all-cause mortality was 1900-2000 kcal/day in women and 2400-2600 kcal/day in men. However, after adjusting for BMI, no significant association was observed between the calibrated EI and the risk of death. These associations could not be confirmed in the uncalibrated EI. The HR for mortality was minimal at a BMI of 23 kg/m² in both men and women, with or without adjustment for the calibrated EI.

CONCLUSIONS

Calibrated EI was negatively associated with mortality risk but not uncalibrated EI. This may be mediated by an increase in body weight over time. Caution is required when interpreting the association between EI and mortality risk without adjusting for self-reported measurement errors and outcomes.

Dose-Response Relationships between Diet Quality and Mortality among Frail and Non-Frail Older Adults: A Population-Based Kyoto-Kameoka Prospective Cohort Study

OBJECTIVES

Although better diet quality is inversely associated with mortality risk, the association between diet quality and mortality remains unclear in frail and non-frail older adults. Thus, we aimed to examine this association in older Japanese adults.

DESIGN

A prospective cohort study.

SETTING AND PARTICIPANTS

We used the data of 8,051 Japanese older adults aged ≥65 years in the Kyoto-Kameoka study.

MESUREMENTS

Dietary intake was estimated using a validated food frequency questionnaire. Diet quality was evaluated by calculating the adherence scores to the Japanese Food Guide Spinning Top (range, 0 [worst] to 80 [best]), which were stratified into quartiles. Frailty status was assessed using the validated self-administered Kihon Checklist (KCL) and the Fried phenotype (FP) model. Survival data were collected between February 15, 2012 and November 30, 2016. Statistical analysis was performed using the multivariate Cox proportional hazard analysis and the spline model.

RESULTS

During the median 4.75-year follow-up (36,552 person-years), we recorded 661 deaths. After adjusting for confounders, compared with the bottom adherence score quartile, the top quartile was associated with lower hazard ratio (HR) of mortality in frailty (HR, 0.73; 95% confidence interval [CI], 0.54-1.00) and non-frailty, as defined by the KCL (HR, 0.72; 95% CI, 0.52-1.01). In the spline model, regardless of frailty status defined by the KCL and FP model, adherence score showed a strongly dose-dependent inverse association with mortality up to approximately 55 points; however, no significant differences were observed thereafter. This association was similar to the results obtained in individuals with physical, cognitive, and depression as domains of KCL in the spline model.

CONCLUSIONS

Our findings demonstrate an L-shaped association between diet quality and mortality in both frail and non-frail individuals. This study may provide important knowledge for improving poor diet quality in older individuals with frailty or domains of frailty.