Young adult weight trajectories through midlife by body mass category.

OBJECTIVE: To estimate the expected weight gain through midlife for those in a given BMI category in young adulthood. DESIGN AND METHODS: Group-based trajectory modeling and National Longitudinal Survey of Youth 1979 data from 1990 to 2008 were used to quantify weight trajectories through midlife for 10,038 young adult men and women stratified by BMI category. Logistic regression was used to assess the association of trajectory membership with obesity-related conditions (hypertension, diabetes, arthritis) in middle age. RESULTS: Annual weight gain averaged 0.53 kg (1.17 lb) across the entire sample. However, there was considerable variation by and within BMI categories. More than 98% of men and 92% of women were on upward-sloping trajectories, generally moving into a higher BMI category by middle age. Those who experienced early and rapid weight gain during young adulthood were most likely to be on a steeper trajectory and had greater risks for obesity-related conditions. CONCLUSION: This study points to the health and weight benefits of entering young adulthood with a normal BMI, but further reveals that this is no guarantee of maintaining a healthy weight through midlife. For those who are young adults today, weight maintenance is unlikely to occur without significant environmental or technical innovation.

Expert estimates of caregiver hours for older Singaporeans with dementia.

AIM: To obtain experts' estimates of the number of non-medical care hours required by older Singaporeans at different stages of ageing-related dementia, with low or high behavioural features. METHODS: Experts on dementia in Singapore attended one of two meetings where they provided estimates of the number of care hours required for individuals at mild, moderate and severe levels of dementia with either low or high behavioural features. The experts were shown the collated responses, given an opportunity to discuss as a group, and then polled again. RESULTS: The estimated mean care hours varied by dementia severity and the level of behavioural features. There was no interaction between dementia severity and behavioural features. CONCLUSION: Estimated care hours needed by individuals with dementia is independently influenced by severity of dementia and behavioural features. These estimates may be useful for policy-makers in projecting the impact of caregiving.

Chapter 5: assessing risk of bias as a domain of quality in medical test studies.

Assessing methodological quality is a necessary activity for any systematic review, including those evaluating the evidence for studies of medical test performance. Judging the overall quality of an individual study involves examining the size of the study, the direction and degree of findings, the relevance of the study, and the risk of bias in the form of systematic error, internal validity, and other study limitations. In this chapter of the Methods Guide for Medical Test Reviews, we focus on the evaluation of risk of bias in the form of systematic error in an individual study as a distinctly important component of quality in studies of medical test performance, specifically in the context of estimating test performance (sensitivity and specificity). We make the following recommendations to systematic reviewers: 1) When assessing study limitations that are relevant to the test under evaluation, reviewers should select validated criteria that examine the risk of systematic error, 2) categorizing the risk of bias for individual studies as "low," "medium," or "high" is a useful way to proceed, and 3) methods for determining an overall categorization for the study limitations should be established a priori and documented clearly.

Future living arrangements of Singaporeans with age-related dementia.

BACKGROUND: With rapid aging, Singapore faces an increasing proportion of the population with age-related dementia. We used system dynamics methodology to estimate the number and proportion of people with mild, moderate, and severe dementia in future years and to examine the impact of changing family composition on their likely living arrangements. METHODS: A system dynamics model was constructed to estimate resident population, drawing birth and mortality rates from census data. We simulate future mild, moderate, and severe dementia prevalence matched with estimates of total dementia prevalence for the Asian region that includes Singapore. Then, integrating a submodel in which family size trends were projected based on fertility rates with tendencies for dependent elderly adults with dementia to live with family members, we estimate likely living arrangements of the future population of individuals with dementia. RESULTS: Though lower than other previous estimates, our simulation results indicate an increase in the number and proportion of people in Singapore with severe dementia. This and the concurrent decrease in family size point to an increasing number of individuals with dementia unlikely to live at home. CONCLUSIONS: The momenta of demographic and illness trends portend a higher number of individuals with dementia less likely to be cared for at home by family members. Traditions of care for frail elderly found in the diverse cultures of Singapore will be increasingly difficult to sustain, and care options that accommodate these demographic shifts are urgently needed.