Assessing Differential Effects of Somatic Amplification to Positive Affect in Midlife and Late Adulthood-A Regression Mixture Approach.

This study aims to provide an empirical demonstration of a novel method, regression mixture model, by examining differential effects of somatic amplification to positive affect and identifying the predictors that contribute to the differential effects. Data derived from the second wave of Midlife in the United States. The analytic sample consisted of 1,766 adults aged from 33 to 84 years. Regression mixture models were fitted using Mplus 7.4, and a two-step model-building approach was adopted. Three latent groups were identified consisting of a maladaptive (32.1%), a vulnerable (62.5%), and a resilient (5.4%) group. Six covariates (i.e., age, education level, positive relations with others, purpose in life, depressive symptoms, and physical health) significantly predicted the latent class membership in the regression mixture model. The study demonstrated the regression mixture model to be a flexible and efficient statistical tool in assessing individual differences in response to adversity and identifying resilience factors, which contributes to aging research.

Age and task differences in functional fitness in older women: comparisons with Senior Fitness Test normative and criterion-referenced data.

Age-related changes in physical abilities, such as strength and flexibility, contribute to functional losses. However, older individuals may be unaware of what specific physical abilities compromise independent functioning. Three groups of women, aged 60 to 69, 70 to 79, and 80 to 92 years, were administered the Senior Fitness Test (SFT) to determine age differences in physical abilities and risk for functional losses. The oldest group showed significant differences in lower body strength, aerobic endurance, and agility and dynamic balance when compared with the other groups who performed similarly. Across all groups, a faster rate of decline was found for lower body strength (50.6%) and dynamic balance and agility (45.7%) than upper body strength (21.3%) and aerobic endurance (33.6%). Criterion-referenced (CR) fitness standards suggested that 45% of the individuals were at risk for loss of independent functioning. This study highlights age-related differences in physical abilities and the risk for the loss of independence in later life.

The angiotensin-converting enzyme gene insertion/deletion polymorphism interacts with fear of falling in relation to stepping speed in community-dwelling older adults.

BACKGROUND: Despite the association of genetic factors with falls, balance, and lower extremity functioning, interaction of the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism with fear of falling (FOF) in relation to stepping performance has, to the best of our knowledge, not been investigated in older adults. OBJECTIVE: The purpose of this study was to examine the interaction effects of the ACE I/D polymorphism with FOF in relation to stepping performance in older adults. METHODS: Eighty-eight community-dwelling adults 60 years or older participated in a cross-sectional observational study. Participants completed tests of rapid and distance stepping, and self-reported FOF (yes/no). Participants provided saliva for ACE genotyping. General linear models evaluated ACE genotype × FOF interaction effects in relation to stepping performance. The α level was set at 0.05. RESULTS: The ACE I/D polymorphism exhibited significant interaction effects (p for interactions 0.002 ≤ p ≤ .04) with FOF in relation to stepping speed. Relationships between FOF and stepping speed varied among ACE genotypes. The insertion/insertion (II) genotype was significantly associated (p = .01) with slow stepping in individuals with, but not without FOF (p > .05). CONCLUSION: Variation in relationships between FOF and stepping speed among ACE genotypes suggests a role for the ACE I/D polymorphism in modifying relationships between FOF and stepping speed in older adults. The association of the ACE II genotype with slow stepping performance in individuals with, but not without FOF, suggests that older adults with the ACE II genotype and FOF may be at increased risk for poor stepping performance and associated functional declines.

Angiotensin-Converting Enzyme Insertion/Deletion Polymorphism, Lower Extremity Strength, and Physical Performance in Older Adults.

BACKGROUND: Evidence for associations between the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene and physical performance is conflicting. Furthermore, investigations of relationships between lower extremity strength and physical performance have usually not considered the role of the ACE genotype, and it is unclear whether there are variations in relationships between lower extremity strength and physical performance among ACE genotypes in older adults. OBJECTIVE: The objectives of this study were to investigate associations between the ACE I/D polymorphism and physical performance and to determine whether relationships between lower extremity strength and physical performance vary among ACE genotypes in older adults. DESIGN: This was a cross-sectional observational study. METHODS: Community-dwelling adults (N = 88) who were at least 60 years old completed physical performance and lower extremity strength tests. After DNA was extracted from saliva, ACE I/D polymorphism genotyping was done. The Spearman rank order correlation coefficient was used to examine associations between lower extremity strength and physical performance within ACE genotype subgroups. Analysis of covariance and linear regression were used to examine ACE genotype and ACE genotype × lower extremity strength interaction effects in relation to physical performance. RESULTS: Genotype-specific correlation coefficients exhibited substantial variation among ACE genotype subgroups; however, differences did not attain statistical significance. Statistically significant genotype × lower extremity strength interaction effects in relation to physical performance were detected. LIMITATIONS: The cross-sectional design precludes inferring causal relationships between strength and performance. The small sample size contributed to limited power to detect additional interaction effects and to detect statistically significant differences between correlation coefficients among ACE genotype subgroups. CONCLUSIONS: The ACE I/D polymorphism is, interactively with lower extremity strength, associated with physical performance. Genotype-specific correlation coefficients and ACE genotype × lower extremity strength interaction effects on physical performance are consistent with variations in relationships between lower extremity strength and performance among ACE genotype subgroups.

Impact of a Leadership Development Program for Students in a Doctor of Physical Therapy Program.

AIMS: Physical therapists are needed in leadership roles to enhance participation in primary care delivery models. This study's purpose was to investigate the impact of a leadership development course in a Doctor of Physical Therapy (DPT) curriculum on student physical therapist leadership practices. It was anticipated that students who completed a structured leadership development course would have a greater increase of leadership practices as measured by the Leadership Practices Inventory-Self (LPI-Self). LITERATURE REVIEW: Published articles on DPT student leadership offer foundational insight into mechanisms for enhancing leadership development. Little evidence exists in understanding how student physical therapists develop leadership practices. PARTICIPANTS: Ten DPT students participated in an elective leadership development pro¬gram; 22 classmates served as controls. METHODS: This was a pretest/posttest quasi-experimental design. The LPI-Self and a demographic survey were completed prior to and immediately after a leadership development course. RESULTS: A significant increase (p=0.030) was found in total change score of the LPI-Self pre- to post-test in the experimental group compared to the control group. CONCLUSION: DPT students who participated in the leadership development program had significant increase in LPI-Self scores. These findings suggest that intentional leadership development implemented in DPT curriculum can increase leadership practices.

Construct validity of the Modified Gait Efficacy Scale in older females.

There are few well-validated tools that focus on the assessment of walking confidence in older adults. The main objective of this study was to assess construct validity of the 10-item Modified Gait Efficacy Scale (mGES) as a measure of walking confidence in older adults. Twenty-four older females completed the mGES, the 16-item Activities-specific Balance Confidence (ABC-16) scale, and the Senior Fitness Test (SFT). Construct validity of the mGES was evaluated by quantifying relationships between the mGES and the ABC-16 and the SFT, and by examining the ability of the mGES to discriminate between known groups (no/lower fear of falling versus higher fear of falling). There was a strong correlation between mGES and the ABC-16 scale (rs = 0.85; p < 0.001). The mGES was significantly associated with SFT components that required lower extremity strength, stepping aerobic endurance, and walking agility and dynamic balance (rs = 0.45 to 0.61; p < 0.05). Relationships between the mGES and number of arm curls in 30 s, chair sit and reach test, and back scratch test were weak (rs = 0.13-0.25; p > 0.05). Mean mGES score was 91.5% in a no/lower fear of falling group, while it was 81.4% in a higher fear group (p = 0.22). There was a trend toward a significant difference in the unstandardized residuals derived from regression of ranked mGES scores on ranked covariate (age and 8 foot up and go) scores, between the no/lower versus higher fear of falling group (p = 0.095). These results support construct validity of the mGES as a measure of gait self-efficacy in community-dwelling older females.

Performance on a test of rapid stepping in community-dwelling older adults: validity, relative and absolute reliability and minimum detectable change.

Reduced stepping speed is associated with balance deficits and falls in older adults. We evaluated psychometric properties of a test of rapid stepping, the Thirty-Rapid-Step test (30-RST) in 37 community-dwelling older adults. Participants performed the 30-RST, dynamic (step execution time, five-times-sit-to-stand test, gait speed, maximum step length and four-square-step test) and static (single-leg-stance-time and postural sway) performance-based tests. Relationships between 30-RST and performance-based tests were evaluated with Spearman's rho. Intraclass correlation coefficient (ICC), standard error of measurement (SEM), 95% limits of agreement and minimum detectable change at the 95% confidence level (MDC95) were computed for the 30-RST. Relationships between 30-RST and dynamic measures were moderate to very good (r = -0.35-0.73, p < 0.05); however, relationships between 30-RST and static balance were weak (r = 0.04-0.19, p > 0.05). The ICC2,1 was 0.85 for 30-RST indicating excellent test-retest reliability. SEM expressed as a percent of mean 30-RST was 8.2%, indicating low measurement error. The MDC95 was 9.4 s, and MDC95 expressed as a percent of mean 30-RST was moderately low at 22.6%. The 30-RST is a valid measure of dynamic balance and mobility with excellent relative and absolute reliability, and may be a useful measure in geriatric clinical settings and studies investigating balance in healthy community-dwelling older adults.

Prosocial behaviours of young adolescents: a focus group study.

This study investigated young adolescents' perceptions of their peers' prosocial behaviours. In eight focus groups, 53 11- to 13-year olds described specific prosocial acts of their peers. Results suggest that traditional research has not addressed the diversity of prosocial behaviours that youth enact, nor emphasized behaviours that are salient to young adolescents. Such behaviours included standing up for others, encouraging others, helping others develop skills, including others who are left out, and being humorous. Facilitating emotional regulation of others emerged as an important component of prosocial behaviour. These data can help guide future research on prosocial development to include a broader array of authentic behaviours of young adolescents.