A Co-Twin Control Study of Physical Function in Elderly African American Women

The Relationship between Pain, Disability, and Sex in African Americans

Older African Americans consistently report diminished capacities to perform activities of daily living (ADL) compared with other racial groups. The extent to which bodily pain is related to declining abilities to perform ADL/ADL disability in African Americans remains unclear, as does whether this relationship exists to the same degree in African American men and women. For nurses to provide optimal care for older African Americans, a better understanding of the relationship between bodily pain and ADL disability and how it may differ by sex is needed. The aim of this study was to examine whether pain, age, education, income, marital status and/or comorbid conditions were associated with ADL disabilities in older African American women and men. This was a cross-sectional descriptive study. The sample included 598 participants (446 women, 152 men) from the first wave of the Baltimore Study on Black Aging. African American women (odds ratio [OR] = 4.06; 95% confidence interval [CI] 2.63-6.26) and African American men (OR = 6.44; 95% CI = 2.84-14.57) who reported bodily pain had greater ADL disability than those who did not report bodily pain. Having two or more comorbid conditions also was significantly associated with ADL disability in African American women (OR = 3.95; 95% CI: 2.09-7.47). Further work is needed to understand pain differences between older African American women and men to develop interventions that can be tailored to meet the individual pain needs of both groups.

Heritability of arthritis in African American twins: findings from the Carolina African American Twins Study of Aging

PURPOSE

To determine the genetic and environmental influences exerted on arthritis by measuring the distribution of self-reported arthritis diagnoses among monozygotic (MZ) and dizygotic (DZ) African American twins.

METHODS

A cross-sectional study was conducted on 97 MZ and 113 DZ twin pairs recruited into the Carolina African American Twin Study of Aging (CAATSA). The sample had a mean age of 47 +/- 13.9 years. A twin design was used to determine correlations in arthritis diagnosis for MZ and DZ twins and to estimate the contribution of genes and environment to the variation in an arthritis diagnosis.

RESULTS

The concordance rate for being diagnosed with arthritis was 42% for MZ twins, and 20% for DZ twins, resulting in a 2.1:1 ratio of MZ to DZ concordance. These results indicate a significant proportion of individual variability was due to genetic factors (43%) on an arthritis diagnosis as well as 57% of variance due to nonshared environmental influences.

CONCLUSION

This research suggests that while there are genetic influences on arthritis diagnosis, environmental factors, such as infections, dietary factors, urbanization, and pollutants, also play a role in accounting for variability in the diagnosis and treatment of arthritis among diverse populations.

Twin study of depressive symptoms among older african-american women

This study examines factors associated with depressive symptoms in a genetically informative sample of African-American female twins aged 65 years and older. A telephone interview was conducted with 180 pairs of twins. Questions included demographics, health behaviors, health status, activities of daily living (ADLs), instrumental ADLs, and depressive symptoms as measured by the Center for Epidemiologic Studies-Depression scale. Regression methods for clustered data were used to examine the associations. In univariate analyses, ADLs (odds ratio or OR = 1.4, 95% confidence interval or CI = 1.1-1.7), fractures (OR = 4.4, 95% CI = 1.3-15.6), and vision problems (OR = 1.9, 95% CI = 1.0-3.8) were significantly associated with depressive symptoms. In multivariable analyses, ADLs (OR = 1.4, 95% CI = 1.2-1.7) and vision problems (OR = 2.0, 95% CI = 1.2-3.5) remained significantly associated with depressive symptoms. A within-pair analysis, controlling for genetic or familial influences, produced similar results. The results suggest that efforts targeted at reducing levels of disability may reduce depressive symptoms in this population.

The impact of cognitive functioning on mortality and the development of functional disability in older adults with diabetes: the second longitudinal study on aging

Background

For older adults without diabetes, cognitive functioning has been implicated as a predictor of death and functional disability for older adults and those with mild to severe cognitive impairment. However, little is known about the relationship between cognition functioning on mortality and the development of functional disability in late life for persons with diabetes. We examined the relative contribution of cognitive functioning to mortality and functional disability over a 2-year period in a sample of nationally representative older US adults with diabetes who were free from cognitive impairment through secondary data analyses of the Second Longitudinal Study of Aging (LSOA II).

Methods

Participants included 559 US adults (232 males and 327 females) ≥ 70 years old who had diabetes and who were free from cognitive impairment were examined using an adapted Telephone Interview of Cognitive Status (TICS), Activities of Daily Living (ADL), and Instrumental Activities of Daily Living (IADL).

Results

Multivariate logistic regression was conducted to investigate the independent contribution of cognitive functioning to three mutually exclusive outcomes of death and two measures of functional disability status. The covariates included in the model were participants' sex, age, race, marital status, educational level, duration of diabetes, cardiovascular disease (CVD) status, and self-rated health. Persons with diabetes who had the lowest levels of cognitive functioning relative to the highest level of cognitive functioning had a greater odds of dying (AOR = 0.80, 95% CI = 0.67–0.96) or becoming disabled (AOR = 0.87, 95% CI = 0.78–0.97) compared to those people who were disability free.

Conclusion

Older adults with diabetes and low normal levels of cognition, yet within normal ranges, were approximately 20% more likely to die and 13% more likely to become disabled than those with higher levels of cognitive functioning over a 2-year period. Brief screening measures of cognitive functioning could be used to identify older adults with diabetes who are at increased risk for mortality and functional disability, as well as those who may benefit from interventions to prevent or minimize further disablement and declines in cognitive functioning.

Physical Function and Its Response to Exercise: Associations With Cytokine Gene Variation in Older Adults With Knee Osteoarthritis

BACKGROUND

We determined whether physical function and its response to exercise training are associated with polymorphisms in cytokine genes (interleukin-6 [IL-6] -174 G/C; tumor necrosis factor alpha [TNFalpha] -308 G/A and -238 G/A; and TNFalpha receptors [TNFR]1 +36 A/G, TNFR2 +676 T/G, and TNFR2 +1663 A/G), in 214 older (> or =60 years), overweight (body mass index > or =28 kg/m(2)) individuals with knee osteoarthritis.

METHODS

Physical function (walking distance, stair-climb time, self-reported disability) was measured before and after an 18-month randomized, controlled exercise trial involving walking and weight lifting 3 days/week.

RESULTS

In cross-sectional analyses, baseline walking distance was greater in individuals homozygous for the major G allele at IL-6 -174 compared to individuals with at least one C allele (p = .05). Both walking distance (p =.02) and stair-climb time (p = .003) were better in individuals homozygous for the major G allele of the TNFalpha -308 polymorphism compared to those with at least one A allele. Walking distance was better (p = .02), and stair-climb time tended to be better (p = .06), in individuals homozygous for the major T allele of the TNFR2 +676 polymorphism. No associations were seen with self-reported physical disability nor with the other polymorphisms. In response to exercise, there was a significant interaction between TNFalpha -308 genotype and exercise treatment on 6-month changes in stair-climb time (p = .007), and on 18-month changes in self-reported physical disability (p = .01), such that individuals with an A allele showed greater improvement in response to exercise.

CONCLUSIONS

Walking distance and stair climbing speed are partly influenced by genetic variation in the IL-6 and TNFalpha genes in older individuals with knee osteoarthritis.