Associations of grip strength and walking pace with mortality in stroke survivors: A prospective study from UK Biobank

INTRODUCTION

Although stroke is an emerging cause of disability and mortality globally, associations between physical capability markers and mortality in stroke survivors are elusive. This study investigated the individual and combined associations of walking pace and grip strength with all-cause and stroke mortality in stroke survivors.

METHODS

Individual and combined associations of walking pace and grip strength with stroke deaths and all-cause mortality were investigated using Cox proportional-hazard models adjusted for sociodemographic, lifestyle, and health-related variables.

RESULTS

Seven thousand four hundred eighty-six stroke survivors from the UK Biobank study (aged 40-70 years; 42.4% women) were included in this prospective study. Over a median follow-up of 12.6 (IQR: 11.9-13.3) years, 1490 (19.9%) participants died, of whom 222 (3.0%) died from stroke. After adjusting for confounding factors, and compared to individuals in the average/brisk walking pace category, those who reported a slow walking pace had 2.00 (95% CI: 1.50-2.68) and 1.99 (95% CI: 1.78-2.23) times higher risk of stroke mortality and all-cause mortality, respectively. Similar associations were identified for participants with low grip strength compared with those with normal levels. For combined associations, those with both slow walking pace and low grip strength showed the highest risk of stroke mortality (hazard ratio: 2.86 [95% CI: 1.93-4.22]). Similar results were found for all-cause mortality.

CONCLUSIONS

Low grip strength and slow walking pace were associated with a higher risk of stroke and all-cause mortality in stroke survivors. If these associations are causal, improving physical capability among stroke survivors might potentially prolong survival.

Association between walking pace and incident type 2 diabetes by adiposity level: A prospective cohort study from the UK Biobank

AIMS

To investigate the combined association of adiposity and walking pace with incident type 2 diabetes.

METHODS

We undertook a prospective cohort study in 194 304 White-European participants (mean age 56.5 years, 55.9% women). Participants' walking pace was self-reported as brisk, average or slow. Adiposity measures included body mass index (BMI), waist circumference (WC) and body fat percentage (BF%). Associations were investigated using Cox proportional hazard models, with a 2-year landmark analysis. A four-way decomposition analysis was used for mediation and additive interaction.

RESULTS

The median (interquartile range) follow-up was 5.4 (4.8-6.3) years. During the follow-up period, 4564 participants developed type 2 diabetes. Compared to brisk-walking participants with normal BMI, those with obesity who walked briskly were at an approximately 10- to 12-fold higher risk of type 2 diabetes (hazard ratio [HR] 9.64, 95% confidence interval [CI] 7.24-12.84, in women; HR 11.91, 95% CI 8.80-16.12, in men), whereas those with obesity and walked slowly had an approximately 12- to 15-fold higher risk (HR 12.68, 95% CI 9.62-16.71, in women; HR 15.41, 95% CI 11.27-21.06, in men). There was evidence of an additive interaction between WC and BF% and walking pace among women, explaining 17.8% and 47.9% excess risk respectively. Obesity mediated the association in women and men, accounting for 60.1% and 44.9%, respectively.

CONCLUSIONS

Slow walking pace is a risk factor for type 2 diabetes independent of adiposity. Promoting brisk walking as well as weight management might be an effective type 2 diabetes prevention strategy given their synergistic effects.

Dose-response relationship between device-measured physical activity and incident type 2 diabetes: findings from the UK Biobank prospective cohort study

BACKGROUND

Most studies investigating the association between physical activity (PA) and the risk of type 2 diabetes are derived from self-reported questionnaires, with limited evidence using device-based measurements. Therefore, this study aimed to investigate the dose-response relationship between device-measured PA and incident type 2 diabetes.

METHODS

This prospective cohort study included 40,431 participants of the UK Biobank. Wrist-worn accelerometers were used to estimate total, light, moderate, vigorous and moderate-to-vigorous PA. The associations between PA and incident type 2 diabetes were analysed using Cox-proportional hazard models. The mediating role of body mass index (BMI) was tested under a causal counterfactual framework.

RESULTS

The median follow-up period was 6.3 years (IQR: 5.7-6.8), with 591 participants developing type 2 diabetes. Compared to those achieving < 150 min/week of moderate PA, people achieving 150-300, 300-600 and > 600 min/week were at 49% (95% CI 62-32%), 62% (95% CI 71-50%) and 71% (95% CI 80-59%) lower risk of type 2 diabetes, respectively. For vigorous PA, compared to those achieving < 25 min/week, individuals achieving 25-50, 50-75 and > 75 min/week were at 38% (95% CI 48-33%), 48% (95% CI 64-23%) and 64% (95% CI 78-42%) lower type 2 diabetes risk, respectively. Twelve per cent and 20% of the associations between vigorous and moderate PA and type 2 diabetes were mediated by lower BMI, respectively.

CONCLUSIONS

PA has clear dose-response relationship with a lower risk of type 2 diabetes. Our findings support the current aerobic PA recommendations but suggest that additional PA beyond the recommendations is associated with even greater risk reduction.

TRIAL REGISTRATION

The UK Biobank study was approved by the North West Multi-Centre Research Ethics Committee (Ref 11/NW/0382 on June 17, 2011).

Identifying the Biomarker Profile of Pre-Frail and Frail People: A Cross-Sectional Analysis from UK Biobank

OBJECTIVE

This study aimed to compare the biomarker profile of pre-frail and frail adults in the UK Biobank cohort by sex.

METHODS

In total, 202,537 participants (67.8% women, aged 37 to 73 years) were included in this cross-sectional analysis. Further, 31 biomarkers were investigated in this study. Frailty was defined using a modified version of the Frailty Phenotype. Multiple linear regression analyses were performed to explore the biomarker profile of pre-frail and frail individuals categorized by sex.

RESULTS

Lower concentrations of apoA1, total, LDL, and HDL cholesterol, albumin, eGFRcys, vitamin D, total bilirubin, apoB, and testosterone (differences ranged from -0.30 to -0.02 per 1-SD change), as well as higher concentrations of triglycerides, GGT, cystatin C, CRP, ALP, and phosphate (differences ranged from 0.01 to 0.53 per 1-SD change), were identified both in pre-frail and frail men and women. However, some of the associations differed by sex. For instance, higher rheumatoid factor and urate concentrations were identified in pre-frail and frail women, while lower calcium, total protein, and IGF-1 concentrations were identified in pre-frail women and frail women and men. When the analyses were further adjusted for CRP, similar results were found.

CONCLUSIONS

Several biomarkers were linked to pre-frailty and frailty. Nonetheless, some of the associations differed by sex. Our findings contribute to a broader understanding of the pathophysiology of frailty as currently defined.

Frailty in Chile: Development of a Frailty Index Score Using the Chilean National Health Survey 2016-2017

BACKGROUND

The Frailty Index (FI) is used to quantify and summarize vulnerability status in people. In Chile, no development and assessment of a FI have been explored.

OBJECTIVE

To develop and evaluate a FI using representative data from Chilean adults aged 40 years and older stratified by sex.

DESIGN

Cross-sectional study.

SETTING

National representative data from the Chilean National Health Survey 2016-2017 (CNHS 2016-2017).

PARTICIPANTS

3,036 participants older than 40 years with complete data for all variables.

MEASUREMENTS

A 49-item FI was developed and evaluated. This FI included deficits from comorbidities, functional limitations, mental health status, physical activity, anthropometry, medications, and falls. A score between 0 and 1 was calculated for each person. Descriptive statistics and linear regression models were employed to evaluate the FI's performance in the population. Comparative analyses were carried out to evaluate the FI score by age (1<60 and ≥ 60 years).

RESULTS

The mean FI score was 0.15 (SD:0.09), with a 99% upper limit of 0.46. Scores were greater in women than men (0.17 [SD:0.09]) vs. 0.12 [0.08]); in people older than 80 years (0.22 [0.11]), and in people with ≤8 years of education (0.18 [0.10]) compared with those with >12 years (0.12 [0.08]). The average age-related increase in the FI was 2.3%. When a cut-off point ≥ 0.25 was applied, the prevalence of frail individuals was 11.8% (95% CI: 10.0 to 13.8) in the general population. The prevalence was higher in women 15.9% [95% CI: 13.3 to 18.9] than men 7.4% [95% CI: 5.3 to 10.1]. In a comparative analysis by age, higher FI mean scores and prevalence of frail were observed in people ≥ 60 than younger than 60.

CONCLUSIONS

The mean FI score and frailty prevalence were higher in women than men, in people with fewer years of formal education, and incremented markedly with age. This FI can be used for early detection of frailty status focusing on women and middle-aged people as a strategy to delay or prevent frailty-related consequences.

Physical activity and risk of depression: does the type and number of activities matter?

BACKGROUND

Depression is ranked as the leading cause of global disability. Physical activity has been identified as a relevant strategy to reduce the incidence of depression. However, specific aspects of physical activity (eg, type of activity or combination) in decreasing the risk of depression have been underexplored. We aimed to investigate the associations of the type of activity, the number of activities participated in, and the combination of different activity types with the risk of depression onset.

METHODS

We included 161 023 participants aged 38-70 years from the UK Biobank study. At baseline, participants reported their participation in walking, light do-it-yourself (DIY) activities, heavy DIY activities, sports, and other exercises. Depression onset was extracted from primary care and hospital admission records. Cox proportional models were performed, with a 2-year landmark analysis. Analyses were controlled by sociodemographic, lifestyle, and health-related covariables, as well as by total time in physical activity and frequency of physical activity.

FINDINGS

A total of 88 723 (55·1%) of 161 023 participants were women and 72 300 (44·9%) were men. 5401 (3·4%) of 161 023 participants developed depression over a median follow-up of 10·01 years (IQR 9·30-10·83). Compared with no physical activity, the hazard ratio (HR) for depression onset was 0·79 (95% CI 0·71-0·88) for participation in walking, 0·81 (0·72-0·91) for light DIY, 0·72 (0·63-0·82) for heavy DIY, 0·62 (0·49-0·78) for sports, and 0·73 (0·65-0·82) for others exercises. The risk of depression decreased by 19% (95% CI 10-27) in those who engaged in one activity, 25% (16-33) in two activities, 31% (21-39) in three activities, 41% (31-49) in four activities, and 58% (44-69) in five activities. Among the ten most frequent combinations, walking for pleasure, light DIY, heavy DIY, and other exercises showed the lowest risk for depression onset (HR 0·57 [95% CI 0·48-0·68]).

INTERPRETATION

Participation in low-intensity activities, such as walking or light DIY, was associated with a lower risk of depression in comparison with no physical activity participation. Encouraging people to combine different physical activities could lower the risk of depression further.

FUNDING

UK Biobank.

Idiopathic osteoarthritis and contracture: causal implications

OBJECTIVE

To use the known association of idiopathic osteoarthritis with contracture as a means of searching for its cause. There are currently two theories concerning this association, one assuming that the contracture is a consequence of the osteoarthritis and the other that it precedes and causes the osteoarthritis. This study tested both theories.

METHODS

Flexion ranges in the 12 finger joints were obtained by goniometric measurement in two samples of normal female subjects, one group with a mean age of 22 years (25 subjects) and one with a mean age of 45 years (50 subjects). The results were compared with the known regional prevalence of osteoarthritis in the finger joints of women.

RESULTS

The older group showed evidence of reduced flexion range consistent with development of contracture in the extensor mechanism of the fingers. The distribution of the contracture showed a strong negative correlation with the regional prevalence of osteoarthritis.

CONCLUSIONS

An early dorsal contracture develops in the fingers of normal subjects, but it is neither a consequence of nor the cause of digital osteoarthritis. The most parsimonious explanation for the association is that both contracture and idiopathic osteoarthritis are independent consequences of failure to use the full movement range. If this hypothesis is correct, the disease could be preventable.