Leo Westbury

Grip strength among community-dwelling older people predicts hospital admission during the following decade

BACKGROUND Lower grip strength on admission to hospital is known to be associated with longer stay, but the link between customary grip and risk of future admission is less clear. OBJECTIVE To compare grip strength with subsequent risk of hospital admission among community-dwelling older people in a U.K. setting. DESIGN Cohort study with linked administrative data. SETTING Hertfordshire, U.K. SUBJECTS A total of 2,997 community-dwelling men and women aged 59-73 years at baseline. METHODS The Hertfordshire Cohort Study (HCS) participants completed a baseline assessment between 1998 and 2004, during which grip strength was measured. Hospital Episode Statistics and mortality data to March 2010 were linked with the HCS database. Statistical models were used to investigate the association of grip strength with subsequent elective, emergency and long-stay hospitalisation and readmission. RESULTS There was a statistically significant negative association between grip strength and all classes of admission in women [unadjusted hazard ratio per standard deviation (SD) decrease in grip strength for: any admission/death 1.10 (95% CI: 1.06, 1.14), elective admission/death 1.09 (95% CI: 1.05, 1.13), emergency admission/death 1.21 (95% CI: 1.13, 1.31), long-stay admission/death 1.22 (95% CI: 1.13, 1.32) and unadjusted relative risk per SD decrease in grip strength for 30-day readmission/death 1.30 (95% CI: 1.19, 1.43)]. These associations remained significant after adjustment for potential confounding factors (age, height, weight for height, smoking, alcohol, social class). In men, unadjusted rates for emergency admission/death, long-stay admission/death and readmission/death were significantly associated with grip strength; associations that similarly withstood adjustment. CONCLUSION This study provides the first evidence that grip strength among community-dwelling men and women in the U.K. is associated with risk of hospital admission over the following decade.

Social isolation and loneliness as risk factors for the progression of frailty: the English Longitudinal Study of Ageing

Abstract Background loneliness and social isolation have been associated with mortality and with functional decline in older people. We investigated whether loneliness or social isolation are associated with progression of frailty. Methods participants were 2,817 people aged ≥60 from the English Longitudinal Study of Ageing. Loneliness was assessed at Wave 2 using the Revised UCLA scale (short version). A social isolation score at Wave 2 was derived from data on living alone, frequency of contact with friends, family and children, and participation in social organisations. Frailty was assessed by the Fried phenotype of physical frailty at Waves 2 and 4, and by a frailty index at Waves 2–5. Results high levels of loneliness were associated with an increased risk of becoming physically frail or pre-frail around 4 years later: relative risk ratios (95% CI), adjusted for age, sex, level of frailty and other potential confounding factors at baseline were 1.74 (1.29, 2.34) for pre-frailty, and 1.85 (1.14, 2.99) for frailty. High levels of loneliness were not associated with change in the frailty index—a broadly based measure of general condition—over a mean period of 6 years. In the sample as a whole, there was no association between social isolation and risk of becoming physically frail or pre-frail, but high social isolation was associated with increased risk of becoming physically frail in men. Social isolation was not associated with change in the frailty index. Conclusion older people who experience high levels of loneliness are at increased risk of becoming physically frail.

Mortality in the Hertfordshire Ageing Study: association with level and loss of hand grip strength in later life

Background weak hand grip strength in later life is a risk factor for disability, morbidity and mortality and is central to definitions of sarcopenia and frailty. It is unclear whether rate of change in grip strength adds to level of grip strength as a risk factor for poor ageing outcomes. Methods study participants were 292 community-dwelling men and women whose grip strength was measured during the 1994/5 (average age 67) and 2003/5 (average age 76) phases of the Hertfordshire Ageing Study, UK. Individual rate of change in grip strength was estimated using a residual change method. Mortality was followed-up to 2011 (42 men and 21 women died). Results average grip strengths in 2003/5 were 38.4 kg (standard deviation [SD] = 8.1) and 23.7 kg (SD = 6.6) for men and women respectively. Average annualised rates of change in grip strength (2003/5 minus 1994/5) were modest owing to a healthy-participant effect (men: -0.12 kg/y, SD = 0.71; women: 0.08 kg/y, SD = 0.54) but varied widely. Mortality risk varied according to level and rate of change in grip strength (P = 0.03); death rates per 100 person years of follow-up were 6.7 (95% CI: 4.6, 9.6) among participants who lost grip over time and had low grip in 2003/5, in contrast with 0.8 (95% CI: 0.1, 5.8) among participants whose grip changed little over time and remained high in 2003/5. Conclusions levels of grip strength in later life should be considered in conjunction with estimates of change in grip strength identified by repeat measurement over time. Normative data for longitudinal change in grip strength are required.

Understanding poor health behaviours as predictors of different types of hospital admission in older people: findings from the Hertfordshire Cohort Study.

Background Rates of hospital admission are increasing, particularly among older people. Poor health behaviours cluster but their combined impact on risk of hospital admission among older people in the UK is unknown. Methods 2997 community-dwelling men and women (aged 59–73) participated in the Hertfordshire Cohort Study (HCS). We scored (from 0 to 4) number of poor health behaviours engaged in at baseline (1998–2004) out of: current smoking, high weekly alcohol, low customary physical activity and poor diet. We linked HCS with Hospital Episode Statistics and mortality data to 31/03/2010 and analysed associations between the score and risk of different types of hospital admission: any; elective; emergency; long stay (>7 days); 30-day readmission (any, or emergency). Results 32%, 40%, 20% and 7% of men engaged in 0, 1, 2 and 3/4 poor health behaviours; corresponding percentages for women 51%, 38%, 9%, 2%. 75% of men (69% women) experienced at least one hospital admission. Among men and women, increased number of poor health behaviours was strongly associated (p<0.01) with greater risk of long stay and emergency admissions, and 30-day emergency readmissions. Hazard ratios (HRs) for emergency admission for 3/4 poor health behaviours in comparison with none were: men, 1.37 (95% CI 1.11 to 1.69); women, 1.84 (95% CI 1.22 to 2.77). Associations were unaltered by adjustment for age, body mass index and comorbidity. Conclusions Clustered poor health behaviours are associated with increased risk of hospital admission among older people in the UK. Lifecourse interventions to reduce number of poor health behaviours could have substantial beneficial impact on health and use of healthcare in later life.

Adult Lifetime Diet Quality and Physical Performance in Older Age: Findings From a British Birth Cohort

Abstract Background Current evidence that links “healthier” dietary patterns to better measured physical performance is mainly from older populations; little is known about the role of earlier diet. We examined adult diet quality in relation to physical performance at age 60–64 years. Methods Diet quality was defined using principal component analysis of dietary data collected at age 36, 43, 53, and 60–64. Throughout adulthood, diets of higher quality were characterized by higher consumption of fruit, vegetables, and wholegrain bread. Diet quality scores calculated at each age indicated compliance with this pattern. Physical performance was assessed using chair rise, timed-up-and-go, and standing balance tests at age 60–64. The analysis sample included 969 men and women. Results In gender-adjusted analyses, higher diet quality at each age was associated with better measured physical performance (all p < .01 for each test), although some associations were attenuated after adjustment for covariates. Diet quality scores were highly correlated in adulthood (0.44 ≤ r ≤ 0.67). However, conditional models showed that higher diet quality at age 60–64 (than expected from scores at younger ages), was associated with faster chair rise speed and with longer standing balance time (adjusted: 0.08 [95% CI: 0.02, 0.15] and 0.07 [0.01, 0.14] SD increase in chair rise speed and balance time, respectively, per SD increase in conditional diet quality; both p < .05). Conclusions Higher diet quality across adulthood is associated with better physical performance in older age. Current diet quality may be particularly important for physical performance, suggesting potential for improvements in diet in early older age.

Association of mitochondrial respiratory chain deficiency in older men with muscle mass and physical performance: findings from the Hertfordshire Sarcopenia Study

Abstract Background Sarcopenia has been defined as low muscle mass and physical performance, and recognition of its importance in clinical practice is growing. Declines in muscle mitochondrial function with age have been described although less is known about the role of mitochondrial dysfunction in sarcopenia. The aim of this study was to investigate whether respiratory chain deficiency is associated with muscle mass and physical performance. Methods Participants were healthy older men from the Hertfordshire Sarcopenia Study. Using immunofluorescence on biopsy samples of the vastus lateralis, we measured concentrations of the NDUFB8 subunit of complex I (C1) and the cytochrome oxidase subunit 1 of complex IV (C4) per fibre. We assessed physical performance using grip strength, walking speed, chair rise time, timed up and go, and standing balance time. We used linear regression with a cluster sandwich estimator to test associations between C1 or C4 and muscle mass and physical performance. Study approval was granted by the Hertfordshire Research Ethics Committee. Findings Data were available from 77 participants (mean age 72·6 years, SD 2·5). The median number of fibres analysed per participant was 157 (IQR 104–237). We expressed C1 and C4 concentrations as z-scores relative to that expected in young controls. The overall participant mean z-scores were 0·3 (SD 1·3) and −1·5 (0·9) for C1 and C4, respectively. We expressed results of physical performance tests as an aggregate performance score between 0 (worst performance) and 5 (best). Each unit (SD) increase in C1 was associated with an increase in performance score of 0·06 (95% CI 0·02–0·09, p=0·003), whereas the association for C4 did not reach significance. We saw no association between C1 or C4 and muscle mass as measured by dual-energy x-ray energy absorptiometry. Interpretation We saw marked heterogeneity in C1 and C4, both between and within participants, as well as an apparent age-related decline in C4. The finding of a small but statistically significant positive association between C1 concentrations and physical performance suggests that mitochondrial dysfunction might have a role in the development of sarcopenia. These findings will help inform the design of future studies across a wider range of ages in both women and men. Funding Biotechnology and Biological Sciences Research Council, Medical Research Council, British Geriatrics Society, Wellcome Trust Centre for Mitochondrial Research, National Institute for Health Research Newcastle Biomedical Research Centre in Ageing and Chronic Disease.

The Impact of Lumbar Spinal Stenosis, Knee Osteoarthritis, and Loss of Lumbar Lordosis on the Quality of Life: Findings from the Katsuragi Low Back Pain Study

Introduction Musculoskeletal diseases and spinal malalignment are associated with poorer quality of life (QOL) in the elderly. However, to date, few general population cohort studies have focused on these conditions together. Our objectives were to clarify the associations between musculoskeletal degenerative diseases and/or spinal malalignment with QOL measures in a group of Japanese older adults. Methods In this cross-sectional study, we analyzed data from 334 individuals recruited from the local population (120 men, 214 women; mean age 62.7 years; range 40-75). Low back pain (LBP) was assessed by questionnaire, and lumbar spinal stenosis (LSS) was diagnosed using a validated lumbar spinal stenosis support tool. Knee osteoarthritis (KOA) was diagnosed by the presence of clinical knee pain plus radiographic KOA. Spinal radiographs were used to assess the degree of lumbar lordosis (LL) and sagittal vertical alignment (SVA). QOL assessment was performed using the Oswestry Disability Index (ODI). A score of 12 was used as a cut-off point for poor QOL. Results Overall, 107 (32.0%) participants had an ODI > 12 (cases), and the remaining 227 individuals were designated controls. LBP, LSS, KOA, and LL were associated with poorer QOL, both in basic models and models adjusted for age, sex, and BMI. Associations persisted after adjustment for other musculoskeletal outcomes. Conclusions In a free-living Japanese population, the poor QOL odds are increased by LBP, LSS, KOA, and certain spinal radiographic features, loss of LL, and increased SVA. Poor QOL odds were greatest in those diagnosed with LSS or KOA. From spinal radiographs, decreased LL and increased SVA were also predictors of poor QOL.

Muscle Mass, Muscle Morphology and Bone Health Among Community-Dwelling Older Men: Findings from the Hertfordshire Sarcopenia Study (HSS)

Sarcopenia and osteoporosis are associated with poor health outcomes in older people. Relationships between muscle and bone have typically been reported at a functional or macroscopic level. The aims of this study were to describe the relationships between muscle morphology and bone health among participants of the Hertfordshire Sarcopenia Study (HSS). 105 older men, mean age 72.5 (SD 2.5) years, were recruited into the HSS. Whole body lean mass as well as appendicular lean mass, lumbar spine and femoral neck bone mineral content (BMC) and bone mineral density (BMD) were obtained through dual-energy X-ray absorptiometry scanning. Percutaneous biopsy of the vastus lateralis was performed successfully in 99 participants. Image analysis was used to determine the muscle morphology variables of slow-twitch (type I) and fast-twitch (type II) myofibre area, myofibre density, capillary and satellite cell (SC) density. There were strong relationships between whole and appendicular lean body mass in relation to femoral neck BMC and BMD (r ≥ 0.43, p < 0.001). Type II fibre area was associated with both femoral neck BMC (r = 0.27, p = 0.01) and BMD (r = 0.26, p = 0.01) with relationships robust to adjustment for age and height. In unadjusted analysis, SC density was associated with whole body area (r = 0.30, p = 0.011) and both BMC (r = 0.26, p = 0.031) and area (r = 0.29, p = 0.017) of the femoral neck. We have demonstrated associations between BMC and changes in muscle at a cellular level predominantly involving type II myofibres. Interventions targeted at improving muscle mass, function and quality may improve overall musculoskeletal health. Larger studies that include women are needed to explore these relationships further.

Risk factors for incident falls in older men and women: the English longitudinal study of ageing

BackgroundFalls are a major cause of disability and death in older people, particularly women. Cross-sectional surveys suggest that some risk factors associated with a history of falls may be sex-specific, but whether risk factors for incident falls differ between the sexes is unclear. We investigated whether risk factors for incident falls differ between men and women.MethodsParticipants were 3298 people aged ≥60 who took part in the Waves 4–6 surveys of the English Longitudinal Study of Ageing. At Wave 4, they provided information about sociodemographic, lifestyle, behavioural and medical factors and had their physical and cognitive function assessed. Data on incident falls during the four-year follow-up period was collected from them at Waves 5 and 6. Poisson regression with robust variance estimation was used to derive relative risks (RR) for the association between baseline characteristics and incident falls.ResultsIn multivariable-adjusted models that also controlled for history of falls, older age was the only factor associated with increased risk of incident falls in both sexes. Some factors were only predictive of falls in one sex, namely more depressive symptoms (RR (95% CI) 1.03 (1.01,1.06)), incontinence (1.12 (1.00,1.24)) and never having married in women (1.26 (1.03,1.53)), and greater comorbidity (1.04 (1.00,1.08)), higher levels of pain (1.10 (1.04,1.17) and poorer balance, as indicated by inability to attempt a full-tandem stand, (1.23 (1.04,1.47)) in men. Of these, only the relationships between pain, balance and comorbidity and falls risk differed significantly by sex.ConclusionsThere were some differences between the sexes in risk factors for incident falls. Our observation that associations between pain, balance and comorbidity and incident falls risk varied by sex needs further investigation in other cohorts.

Mitochondrial respiratory chain deficiency in older men and its relationship with muscle mass and performance

Sarcopenia is the loss of muscle mass and physical performance with age, and recognition of its importance in clinical practice is growing. Age‐related decline in muscle mitochondrial function has been described although less is known about the role of mitochondrial dysfunction in sarcopenia. The aim of this study was to investigate whether respiratory chain deficiency is associated with muscle mass and physical performance among a sample of healthy older men participating in the Hertfordshire Sarcopenia Study.