Alan Marshall

Cohort differences in the levels and trajectories of frailty among older people in England

Background The level of frailty in the older population across age cohorts and how this changes is a factor in determining future care costs and may also influence the extent of socioeconomic and gender inequalities in frailty. Methods We model cohort-specific trajectories in frailty among the community dwelling population older than 50 years, using five waves (2002–2010) of the English Longitudinal Study of Ageing. We stratify our analysis by wealth and gender and use a frailty index, based on accumulation of ‘deficits’. Results For males and females between the ages of 50 and 70 in 2002, frailty trajectories for adjacent age cohorts converge. However, levels of frailty are higher in recent compared with earlier cohorts at the older ages (for cohorts aged over 70 in 2002). These cohort differences are largest in the poorest wealth group, while for the most affluent, frailty trajectories overlap across all adjacent cohorts suggesting no change across cohorts. Conclusions A key driver of the cohort differences in frailty that we observe is likely to be increased survival of frail individuals. Importantly, this paper illustrates that the social conditions experienced across the wealth distribution impacts on the rate of deficit accumulation in older populations. Our results on trajectories of frailty between 2002 and 2010 are pessimistic and, in the context of rising life expectancies, suggest that poorer older people in particular spend additional years of life in a frail state.

Slowing down of adult body mass index trend increases in England: a latent class analysis of cross-sectional surveys (1992-2010)

Background:The prevalence of excess body weight, commonly measured as body mass index (BMI)⩾25 kg m−2, has increased substantially in many populations worldwide over the past three decades, but the rate of increase has slowed down in some western populations.Objective:We address the hypothesis that the slowing down of BMI trend increases in England reflects a majority sub-population resistant to further BMI elevation.Design:Pseudo-panel data derived from annual cross-sectional surveys, the Health Surveys for England (1992–2010). Trends in median BMI values were explored using regression models with splines, and gender-specific mixture model (latent class analysis) were fit to take an account of increasing BMI distribution variance with time and identify hidden subgroups within the population.Subjects:BMI was available for 164 155 adults (men: 76 382; women: 87 773).Results:Until 2001, the age-adjusted yearly increases in median BMI were 0.140 and 0.139 kg m−2 for men and women, respectively, decreasing thereafter to 0.073 and 0.055 kg m−2 (differences between time periods, both P-values<0.0001). The mixture model identified two components—a normal BMI and a high BMI sub-population—the proportions for the latter were 23.5% in men and 33.7% in women. The remaining normal BMI populations were ‘resistant’ with minimal increases in mean BMI values over time. By age, mean BMI values in the normal BMI sub-population increased greatest between 20 and 34 years for men; for women, the increases were similar throughout age groups (slope differences, P<0.0001).Conclusion:In England, recent slowing down of adult BMI trend increases can be explained by two sub-populations—a high BMI sub-population getting ‘fatter’ and a majority ‘resistant’ normal BMI sub-population. These findings support a targeted, rather than a population-wide, policy to tackle the determinants of obesity.

Does pain predict frailty in older men and women? : findings from the English Longitudinal Study of Ageing (ELSA)

Abstract Background: Pain has been suggested to act as a stressor during aging, potentially accelerating declines in health and functioning. Our objective was to examine the longitudinal association between self-reported pain and the development, or worsening, of frailty among older men and women. Methods: The study population consisted of 5,316 men and women living in private households in England, mean age 64.5 years, participating in the English Longitudinal Study of Ageing (ELSA). Data from Waves 2 and 6 of ELSA were used in this study with 8 years of follow-up. At Wave 2, participants were asked whether they were “often troubled with pain” and for those who reported yes, further information regarding the intensity of their pain (mild, moderate, or severe) was collected. Socioeconomic status (SES) was assessed using information about the current/most recent occupation and also net wealth. A frailty index (FI) was generated, with the presence of frailty defined as an FI >0.35. Among those without frailty at Wave 2, the association between pain at Wave 2 and frailty at Wave 6 was examined using logistic regression. We investigated whether pain predicted change in FI between Waves 2 and 6 using a negative binomial regression model. For both models adjustments were made for age, gender, lifestyle factors, depressive symptoms, and socioeconomic factors. Results: At Wave 2, 455 (19.7%) men and 856 (28.7%) women reported they often experienced moderate or severe pain. Of the 5,159 participants who were nonfrail at Wave 2, 328 (6.4%) were frail by Wave 6. The mean FI was 0.11 (standard deviation [SD] = 0.1) at Wave 2 and 0.15 (SD = 0.1) at Wave 6. After adjustment for age, gender, body mass index, lifestyle factors, and depressive symptoms, compared to participants reporting no pain at Wave 2 those reporting moderate (odds ratio [OR] = 3.08, 95% confidence interval [CI] = 2.28, 4.16) or severe pain (OR = 3.78, 95% CI = 2.51, 5.71) were significantly more likely to be frail at Wave 6. This association persisted after further adjustment for either occupational class and/or net wealth level. Compared to those without pain, those with mild, moderate, or severe pain were also more likely to develop worsening frailty, as assessed using the FI, and this association persisted after adjustment for SES. There was no evidence that the association between pain and frailty was influenced by gender. Conclusion: Pain is associated with an increased risk and intensity of frailty in older men and women. Socioeconomic factors contribute to the occurrence of frailty; though in our study do not explain the relationship between pain and frailty.

Crystallinity of ethylene oxide oligomers

Abstract Nonaethylene glycol and pentadecaethylene glycol and their dimethyl ethers have been prepared and characterized, with respect to crystallinity by wide- and small-angle X-ray scattering, Raman scattering, i.r. spectroscopy and differential scanning calorimetry. Wide-angle X-ray scattering is similar to that from high molecular weight poly(ethylene oxide). The crystal habit is lamella. The lamellae are highly crystalline and the surface layers are ordered. Comparison with crystalline poly(ethylene oxide) prepared conventionally, and having a distribution of chain lengths, shows that such samples crystallize into lamellae with disordered surface layers.

Body mass index relates weight to height differently in women and older adults: serial cross-sectional surveys in England (1992-2011).

Background Body mass index (BMI) tends to be higher among shorter adults, especially women. The dependence of BMI–height correlation on age and calendar time may inform us about temporal determinants of BMI. Methods Series of cross-sectional surveys: Health Survey for England, 1992–2011. We study the Benn Index, which is the coefficient in a regression of log(weight) on log(height). This is adjusted for age, gender and calendar time, allowing for non-linear terms and interactions. Results By height quartile, mean BMI decreased with increasing height, more so in women than in men (P < 0.001). The decrease in mean BMI in the tallest compared with the shortest height quartile was 0.77 in men (95% CI 0.69, 0.86) and 1.98 in women (95% CI 1.89, 2.08). Regression analysis of log(weight) on log(height) revealed that the inverse association between BMI and height was more pronounced in older adults and stronger in women than in men, with little change over calendar time. Conclusions Unlike early childhood, where taller children tend to have higher BMI, adults, especially women and older people, show an inverse BMI–height association. BMI is a heterogeneous measure of weight-for-height; height may be an important and complex determinant of BMI trajectory over the life course.

Physical activity and trajectories of frailty among older adults: Evidence from the English Longitudinal Study of Ageing

Background Frail older adults are heavy users of health and social care. In order to reduce the costs associated with frailty in older age groups, safe and cost-effective strategies are required that will reduce the incidence and severity of frailty. Objective We investigated whether self-reported intensity of physical activity (sedentary, mild, moderate or vigorous) performed at least once a week can significantly reduce trajectories of frailty in older adults who are classified as non-frail at baseline (Rockwood’s Frailty Index [FI] ≤ 0.25). Methods Multi-level growth curve modelling was used to assess trajectories of frailty in 8649 non-frail adults aged 50 and over and according to baseline self-reported intensity of physical activity. Frailty was measured in five-year age cohorts based on age at baseline (50–54; 55–59; 60–64; 65–69; 70–74; 75–79; 80+) on up to 6 occasions, providing an average of 10 years of follow-up. All models were adjusted for baseline sex, education, wealth, cohabitation, smoking, and alcohol consumption. Results Compared with the sedentary reference group, mild physical activity was insufficient to significantly slow the progression of frailty, moderate physical activity reduced the progression of frailty in some age groups (particularly ages 65 and above) and vigorous activity significantly reduced the trajectory of frailty progression in all older adults. Conclusion Healthy non-frail older adults require higher intensities of physical activity for continued improvement in frailty trajectories.

Genetic variant of Interleukin-18 gene is associated with the Frailty Index in the English Longitudinal Study of Ageing

Background: the term frailty refers to a condition of increased vulnerability to stressors among older people, leading to a decline in homeostatic reserve. Frailty often leads to falls, hospitalisation and mortality, hence its importance for the delivery of health care to older adults. The pathophysiological mechanisms behind frailty are not well understood, but the decreased steroid-hormone production and elevated chronic systemic inflammation of older people appear to be major contributors. Method: we used a sample of 3,160 individuals aged 50 or older from the English Longitudinal Study of Ageing and assessed their frailty status according to a Frailty Index. We selected 620 single nucleotide polymorphisms in genes involved in the steroid hormone or inflammatory pathways. We performed linear association analysis. The outcome variable was the square root transformation of the Frailty Index, with age and sex entered as covariates. Results: the strongest signal was detected in the pro-inflammatory Interleukin-18 gene (rs360722, P = 0.0021, β = −0.015). Further significant signals were observed in the Interleukin-12 (rs4679868, P = 0.0062, β = −0.008 and rs9852519, P = 0.0077, β = −0.008), low density lipoprotein receptor-related protein 1 (rs1799986, P = 0.0065, β = 0.011) and Selectin-P (rs6131, P = 0.0097, β = −0.01) genes. None of these associations remain significant after Bonferroni correction. Conclusions: we show potential associations between genetic variants of four genes and the frailty index. These genes are involved in the cholesterol transport and inflammatory pathway and, as such, our results provide further support for the involvement of the immunological processes in frailty of the elderly.

Does the level of wealth inequality within an area influence the prevalence of depression amongst older people

This paper considers whether the extent of inequality in house prices within neighbourhoods of England is associated with depressive symptoms in the older population using the English Longitudinal Study of Ageing. We consider two competing hypotheses: first, the wealth inequality hypothesis which proposes that neighbourhood inequality is harmful to health and, second, the mixed neighbourhood hypothesis which suggests that socially mixed neighbourhoods are beneficial for health outcomes. Our results are supportive of the mixed neighbourhood hypothesis, we find a significant association between neighbourhood inequality and depression with lower levels of depression amongst older people in neighbourhoods with greater house price inequality after controlling for individual socio-economic and area correlates of depression. The association between area inequality and depression is strongest for the poorest individuals, but also holds among the most affluent. Our results are in line with research that suggests there are social and health benefits associated with economically mixed communities.

Ethnic differences in male reproductive hormones and relationships with adiposity and insulin resistance in older men

To assess ethnic differences in male reproductive hormone levels and to determine whether any differences are explained by adiposity, insulin resistance (IR) or comorbidities in older men.

Comparison of hypertension healthcare outcomes among older people in the USA and England

Background The USA and England have very different health systems. Comparing hypertension care outcomes in each country enables an evaluation of the effectiveness of each system. Method The English Longitudinal Study of Ageing and the Health and Retirement Survey are used to compare the prevalence of controlled, uncontrolled and undiagnosed hypertension within the hypertensive population (diagnosed or measured within the survey data used) aged 50 years and above in the USA and in England. Results Controlled hypertension is more prevalent within the hypertensive population in the USA (age 50–64: 0.53 (0.50 to 0.57) and age 65+: 0.51 (0.49 to 0.53)) than in England (age 50–64: 0.45 (0.42 to 0.48) and age 65+: 0.42 (0.40 to 0.45)). This difference is driven by lower undiagnosed hypertension in the USA (age 50–64: 0.18 (0.15–0.21) and age 65+: 0.13 (0.12 to 0.14)) relative to England (age 50–64: 0.26 (0.24 to 0.29) and age 65+: 0.22 (0.20 to 0.24)). The prevalence of uncontrolled hypertension within the hypertensive population is very similar in the USA (age 50–64: 0.29 (0.26 to 0.32) and age 65+: 0.36 (0.34 to 0.38)) and England (age 50–64: 0.29 (0.26 to 0.32) and age 65+: 0.36 (0.34 to 0.39)). Hypertension care outcomes are comparable across US insurance categories. In both countries, undiagnosed hypertension is positively correlated with wealth (ages 50–64). Uncontrolled hypertension declines with rising wealth in the USA. Conclusions Different diagnostic practices are likely to drive the cross-country differences in undiagnosed hypertension. US government health systems perform at least as well as private healthcare and are more equitable in the distribution of care outcomes. Higher undiagnosed hypertension among the affluent may reflect less frequent medical contact.