Assessment of Dietary Intake in Three Cohorts of Advanced Age in Two Countries: Methodology Challenges.

OBJECTIVES: Dietary intake information is key to understanding nutrition-related outcomes. Intake changes with age and some older people are at increased risk of malnutrition. Application, difficulties, and advantages of the 24-hour multiple pass recall (24hr-MPR) dietary assessment method in three cohorts of advanced age in the United Kingdom (UK) and New Zealand (NZ) is described. PARTICIPANTS: The Newcastle 85+ study (UK) recruited a single year birth cohort of people aged 85 years during 2006-7. LiLACS NZ recruited a 10-year birth cohort of Maori (indigenous New Zealanders) aged 80-90 years and a single year birth cohort of non-Maori aged 85 years in 2010. MEASUREMENTS: Two 24hr-MPR were conducted on non-consecutive days by trained assessors. Pictorial resources and language were adapted for the New Zealand and Maori contexts. Detailed methods are described. RESULTS: In the Newcastle 85+ study, 805 (93%) participants consented to the 24-MPR, 95% of whom completed two 24hr-MPR; in LiLACS NZ, 218 (82%) consented and 203 (76%) Maori and 353 (90%) non-Maori completed two 24hr-MPR. Mean time to complete each 24hr-MPR was 22 minutes in the Newcastle 85+ study, and 45 minutes for Maori and 39 minutes for non-Maori in LiLACS NZ. Dietary assessment of participants residing in residential care and those requiring proxy respondents were successfully included in both studies. Most participants (83-94%) felt that data captured by the 24hr-MPR reflected their usual dietary intake. CONCLUSIONS: Dietary assessment using 24hr-MPR was successful in capturing detailed dietary data including information on portion size and time of eating for over 1300 octogenarians in the UK and New Zealand (Maori and non- Maori). The 24hr-MPR is an acceptable method of dietary assessment in this age group.

Advancing our understanding of skeletal muscle across the lifecourse: Protocol for the MASS_Lifecourse study and characteristics of the first 80 participants.

INTRODUCTION: Sarcopenia, the age-related loss of skeletal muscle strength and mass, carries a significant burden for affected individuals. There has been little investigation of sarcopenia using experimental medicine techniques to study human muscle tissue in detail. The aim of the Muscle Ageing Sarcopenia Studies Lifecourse (MASS_Lifecourse) study is to recruit up to 160 participants, equally divided between females and males between ages 45 and 85 years for detailed phenotyping of skeletal muscle health. Here we describe the protocol for the study and the characteristics of the first 80 participants. METHODS: We are recruiting participants from three sources in the north-east of England. Study fieldwork comprises a home visit (or videocall) for consent and assessment of health, cognition, lifestyle, and wellbeing. This is followed by a visit to a clinical research facility for assessment of sarcopenia status and collection of samples including a vastus lateralis muscle biopsy. We produced descriptive statistics for the first 80 participants, including expressing their grip strength relative to normative data in the form of Z-scores. RESULTS: The first 80 participants (53.8 % female) covered the target ages, ranging from 48 to 84 years. They were regularly physically active, reported good physical function and had a prevalence of sarcopenia (including probable sarcopenia) of 11.3 % based on the revised European consensus. Their grip strength was similar to that in the general population, with a mean Z-score of 0.09 standard deviations (95 % CI: -1.64, 1.83) above that expected. CONCLUSIONS: The MASS_Lifecourse study combines comprehensive health and lifestyle data with a range of biological samples including skeletal muscle. The findings from planned analyses should contribute to improvements in the diagnosis, treatment, and prevention of sarcopenia.

The recent secular trend in grip strength among older adults: findings from the English Longitudinal Study of Ageing.

PURPOSE: Weaker grip strength in older adults is associated with adverse health outcomes and is a key component of sarcopenia. The secular trend of grip strength is, therefore, relevant in the setting of ageing populations. A recent study suggested differences in this trend among countries in mainland Europe. We used data from the English Longitudinal Study of Ageing (ELSA) to investigate the recent secular trend of older English adults. METHODS: We used data on participants aged 50-89 having their first measurement of grip strength in waves 2 (2002/2003), 4 (2008/2009) or 6 (2012/2013) of ELSA. Grip was measured using a Smedley dynamometer. We expressed grip values as Z-scores (number of standard deviations above the age and gender mean from normative data) for use in linear regression analyses examining the annual secular trend after adjustment for potential confounders. RESULTS: We included a total of 11,476 participants from the three waves of ELSA. Grip strength declined across the three waves, with mean (SD) Z-scores of 0.01 (0.94), - 0.06 (0.97) and - 0.20 (0.98) in waves 2, 4 and 6, respectively. The annual Z-score decline after adjustments was 0.03 SDs (95% CI 0.02, 0.03) per year. CONCLUSION: We saw evidence of a recent slight decline in the grip strength of older English adults. Over the 9-year period of this study, the decline seen is equivalent to 65-year-olds' mean strength declining to that previously seen in individuals at age 69. Further monitoring of secular trends in grip strength and investigation of possible causes are warranted.

Mitochondrial respiratory chain function and content are preserved in the skeletal muscle of active very old men and women.

INTRODUCTION: The loss of mitochondrial function and content have been implicated in sarcopenia although they have been little studied in the very old, the group in which sarcopenia is most common. In this pilot study, our aim was to determine if mitochondrial respiratory chain function and content are preserved among healthy 85-year-olds. METHODS: We recruited 19 participants (11 female) through their general practitioner and assessed their medical history, functional status and self-reported physical activity. We identified sarcopenia using grip strength, Timed Up-and-Go and bioimpedance analysis. We assessed mitochondrial respiratory chain function using phosphorous magnetic resonance spectroscopy, estimating τ1/2 PCr, the recovery half-time of phosphocreatine in the calf muscles following a bout of aerobic exercise. We performed a biopsy of the vastus lateralis muscle and assessed mitochondrial respiratory chain content by measuring levels of subunits of complex I and IV of the respiratory chain, expressed as Z-scores relative to that in young controls. RESULTS: Participants had a median (IQR) of 2 (1,3) long-term conditions, reported regular aerobic physical activity, and one participant (5.3%) had sarcopenia. Sixteen participants completed the magnetic resonance protocol and the mean (SD) τ1/2 PCr of 35.6 (11.3) seconds was in keeping with preserved mitochondrial function. Seven participants underwent muscle biopsy and the mean fibre Z-scores were -0.7 (0.7) and -0.2 (0.4) for complexes I and IV, respectively, suggesting preserved content of mitochondrial respiratory chain enzymes. CONCLUSION: Muscle mitochondrial respiratory chain function and content are preserved in a sample of active, well-functioning 85-year-olds, among whom sarcopenia was uncommon. The results from this study will help inform future work examining the association between muscle mitochondrial deficiency and sarcopenia.

Serum 25-hydroxyvitamin D concentration and its determinants in the very old: the Newcastle 85+ Study.

SUMMARY: Data on vitamin D status in very old adults are lacking. The aim of this study was to assess 25-hydroxyvitamin D [25(OH)D] concentrations and its predictors in 775 adults aged 85 years old living in North-East England. Low 25(OH)D was alarmingly high during winter/spring months, but its biological significance is unknown. INTRODUCTION: Despite recent concerns about the high prevalence of vitamin D deficiency in much of the British adult and paediatric population, there is a dearth of data on vitamin D status and its predictors in very old adults. The objective of the present study was to describe vitamin D status and its associated factors in a broadly representative sample of very old men and women aged 85 years living in the North East of England (55° N). METHODS: Serum concentrations of 25-hydroxyvitamin D [25(OH)D] were analysed in 775 participants in the baseline phase of the Newcastle 85+ cohort study. Season of blood sampling, dietary, health, lifestyle and anthropometric data were collected and included as potential predictors of vitamin D status in ordinal regression models. RESULTS: Median serum 25(OH)D concentrations were 27, 45, 43 and 33 nmol/L during spring, summer, autumn and winter, respectively. The prevalence of vitamin D deficiency according to North American Institute of Medicine guidelines [serum 25(OH)D <30 nmol/L] varied significantly with season with the highest prevalence observed in spring (51%) and the lowest prevalence observed in autumn (23%; P < 0.001). Reported median (inter-quartile range) dietary intakes of vitamin D were very low at 2.9 (1.2-3.3) µg/day. In multivariate ordinal regression models, non-users of either prescribed or non-prescribed vitamin D preparations and winter and spring blood sampling were associated with lower 25(OH)D concentrations. Dietary vitamin D intake, disability score and disease count were not independently associated with vitamin D status in the cohort. CONCLUSION: There is an alarming high prevalence of vitamin D deficiency (<30 nmol/L) in 85-year-olds living in North East England at all times of the year but particularly during winter and spring. Use of vitamin D containing preparations (both supplements and medications) appeared to be the strongest predictor of 25(OH)D concentrations in these very old adults.

Serum 25-hydroxyvitamin D and cognitive decline in the very old: the Newcastle 85+ Study.

BACKGROUND AND PURPOSE: Studies investigating the association between 25-hydroxyvitamin D [25(OH)D] and cognition in the very old (85+) are lacking. METHODS: Cross-sectional (baseline) and prospective data (up to 3 years follow-up) from 775 participants in the Newcastle 85+ Study were analysed for global (measured by the Standardized Mini-Mental State Examination) and attention-specific (measured by the attention battery of the Cognitive Drug Research test) cognitive performance in relation to season-specific 25(OH)D quartiles. RESULTS: Those in the lowest and highest season-specific 25(OH)D quartiles had an increased risk of impaired prevalent (1.66, 95% confidence interval 1.06-2.60, P = 0.03; 1.62, 95% confidence interval 1.02-2.59, P = 0.04, respectively) but not incident global cognitive functioning or decline in functioning compared with those in the middle quartiles adjusted for sociodemographic, health and lifestyle confounders. Random effects models showed that participants belonging to the lowest and highest 25(OH)D quartiles, compared with those in the middle quartiles, had overall slower (log-transformed) attention reaction times for Choice Reaction Time (lowest, ß = 0.023, P = 0.01; highest, ß = 0.021, P = 0.02), Digit Vigilance Task (lowest, ß = 0.009, P = 0.05; highest, ß = 0.01, P = 0.02) and Power of Attention (lowest, ß = 0.017, P = 0.02; highest, ß = 0.022, P = 0.002) and greater Reaction Time Variability (lowest, ß = 0.021, P = 0.02; highest, ß = 0.02, P = 0.03). The increased risk of worse global cognition and attention amongst those in the highest quartile was not observed in non-users of vitamin D supplements/medication. CONCLUSION: Low and high season-specific 25(OH)D quartiles were associated with prevalent cognitive impairment and poorer overall performance in attention-specific tasks over 3 years in the very old, but not with global cognitive decline or incident impairment.

25-hydroxyvitamin D and increased all-cause mortality in very old women: the Newcastle 85+ study.

OBJECTIVE: To investigate the associations between low and high concentrations of baseline serum 25-hydroxyvitamin D [25(OH)D] and all-cause mortality in very old (≥85 years) men and women over 6 years. DESIGN, SETTING AND SUBJECTS: Prospective mortality data from 775 participants in the Newcastle 85+ Study were analysed for survival in relation to 25(OH)D (season-specific quartiles and predefined cut-off values) and sex using Cox proportional hazards models. The models were fitted to the entire and restricted (nonusers of vitamin D-containing supplements and medication) cohorts. RESULTS: For the entire cohort, mortality was higher in both the lowest and highest 25(OH)D season-specific quartiles [SQ1: hazard ratio (HR) 1.31, 95% confidence interval (CI) 1.01-1.69, P = 0.04; SQ4: HR 1.44, 95% CI 1.12-1.85, P = 0.004] compared with the combined middle quartiles (SQ2 + SQ3), after adjustment for sociodemographic factors. The increased risk for the highest quartile remained significant after further adjustment for lifestyle variables (SQ4: HR 1.37, 95% CI 1.06-1.77, P = 0.02) and was seen only in women in sex-specific analyses. Similarly, in sensitivity analyses with predefined 25(OH)D cut-off values, the highest 25(OH)D concentration (≥75 nmol L(-1) ) was associated with a 2.4-fold increased risk of mortality in women (restricted cohort) after adjusting for all covariates. CONCLUSION: Low and high season-specific 25(OH)D quartiles were associated with increased risks of mortality over 6 years in the very old; this effect was particularly noticeable in women, including those who reported taking vitamin D-containing supplements/medication.

Midlife dietary patterns and mortality in the population-based study of Swedish twins.

BACKGROUND: We examined midlife dietary patterns in relation to (1) sociodemographic and health-related characteristics and (2) survival. METHODS: A two-step cluster analysis of a 12-item food questionnaire was used to derive dietary patterns in a cohort of 16 649 members of the Swedish Twin Registry, a prospective, population-based study of twins. The average age at baseline (1967) was 55.5 years; the follow-up for all-cause mortality extended until 2011 (26.8±12.35 years or 345,127 person-years) via death records. RESULTS: Four dietary patterns (classes) distinguishable by demographic and health characteristics emerged: Moderate Intake and Starch Diet (Class 1), Moderate Intake Diet with Low Flour-Based Foods (Class 2), Meat and Starch Diet (Class 3) and Low Meat Intake Diet (Class 4). Membership in Class 3 was associated with 7% increased risk of mortality compared with Class 2 independent of baseline age, cohort, sex and body mass index. These results were mostly explained by sociodemographic and lifestyle factors. When follow-up was restricted to those in the study for 20+ years, both Classes 1 and 3 conferred increased risk of mortality compared with Class 2, independent of covariates. Analyses conducted within twin pairs revealed similar results. CONCLUSIONS: Midlife diet over-represented by meat and starch-based foods may increase the risk of mortality, whereas the diet low in starch may be beneficial. These results appear to be independent of factors shared by twins, as well as at least partially a function of social and lifestyle factors, particularly marital status and smoking.