@article {1052, title = {Diabetes mellitus and gait dysfunction: possible explanatory factors.}, journal = {Phys Ther}, volume = {88}, year = {2008}, month = {2008 Nov}, pages = {1365-74}, abstract = {

BACKGROUND AND OBJECTIVE: Gait characteristics differ in individuals with diabetes compared with those without diabetes. Limited information regarding potential explanatory factors for this association exists. This study examined the association between diabetes and gait characteristics in older adults and explored potential explanatory factors.

DESIGN: A cross-sectional, observational study design was used.

METHODS: At the 1998-1999 clinic visit, 558 ambulatory older adults (mean age=79 years) from the Pittsburgh site of the Cardiovascular Health Study had an assessment of their gait characteristics, diabetes, health status, cognition, mood, lower-extremity circulation and sensation, vision, lower-extremity strength (force-producing capacity), physical activity, and body mass index (BMI). A series of linear regression models were developed to examine the association between diabetes and gait characteristics and to examine potential explanatory factors for the associations.

RESULTS: Diabetes was related to gait speed (beta=-.06 m/s); however, the association was partially explained by health status variables, cognition, mood, lower-extremity circulation and sensation, visual impairment, lower-extremity strength, physical activity, and BMI. Health status and lower-extremity strength each explained the greatest proportion of the association (beta reduced 66\% by each). Diabetes was related to step width (beta=.02 m), and the association could not be explained by the examined factors.

CONCLUSIONS: Diabetes was associated with gait alterations in older adults. Slowed gait speed appears to be secondary to the peripheral effect of the disease on other body systems. The effect of diabetes on step width was not explained in the analyses and may be related to peripheral motor nerve function or central influences of the disease, which could not be assessed in this study.

}, keywords = {Aged, Body Mass Index, Cognition, Cross-Sectional Studies, Diabetes Mellitus, Female, Gait, Geriatric Assessment, Health Status, Humans, Linear Models, Longitudinal Studies, Male, Multicenter Studies as Topic, Muscle Strength}, issn = {1538-6724}, doi = {10.2522/ptj.20080016}, author = {Brach, Jennifer S and Talkowski, Jaime B and Strotmeyer, Elsa S and Newman, Anne B} } @article {1103, title = {Sleep-disordered breathing and frailty in the Cardiovascular Health Study Cohort.}, journal = {Am J Epidemiol}, volume = {170}, year = {2009}, month = {2009 Jul 15}, pages = {193-202}, abstract = {

Sleep-disordered breathing (SDB) is associated with pathophysiology that may influence the development and progression of frailty. Using data collected in 1995-1996, the authors explored the relation between SDB and components of frailty among 1,042 participants of the Cardiovascular Health Study. Diagnosis of SDB was based on the results of overnight polysomnography, and severe SDB was defined as an apnea-hypopnea index of >30 per hour of sleep. Slow walking speed, low grip strength, exhaustion, low physical activity, and unexplained weight loss were referred to as frailty indicator variables. There were 584 (56\%) female and 458 (44\%) male participants, and the mean age was 77 (standard deviation, 4) years. There was independent association between severe SDB and 1 or more frailty indicator variables (adjusted odds ratio = 4.85, 95\% confidence interval: 1.40, 16.78), slow walking speed (adjusted odds ratio = 2.67, 95\% confidence interval: 1.04, 6.84), and low grip strength (adjusted odds ratio = 3.29, 95\% confidence interval: 1.36, 7.96) among female study participants. The finding of an independent association between SDB and frailty indicator variables among older women could have important implications in interventions aimed at preventing or delaying the progression of frailty.

}, keywords = {Activities of Daily Living, Aged, Cardiovascular Diseases, Cardiovascular System, Cohort Studies, Confidence Intervals, Exercise Tolerance, Female, Frail Elderly, Hand Strength, Humans, Logistic Models, Male, Mobility Limitation, Models, Statistical, Motor Activity, Muscle Strength, Odds Ratio, Polysomnography, Psychometrics, Risk Factors, Sleep Apnea, Obstructive, Weight Loss}, issn = {1476-6256}, doi = {10.1093/aje/kwp108}, author = {Endeshaw, Yohannes W and Unruh, Mark L and Kutner, Michael and Newman, Anne B and Bliwise, Donald L} } @article {1352, title = {Serum 25-hydroxyvitamin D and physical function in older adults: the Cardiovascular Health Study All Stars.}, journal = {J Am Geriatr Soc}, volume = {59}, year = {2011}, month = {2011 Oct}, pages = {1793-801}, abstract = {

OBJECTIVES: To examine the association between 25-hydroxyvitamin D (25(OH)D) and physical function in adults of advanced age.

DESIGN: Cross-sectional and longitudinal analysis of physical function over 3~years of follow-up in the Cardiovascular Health Study All Stars.

SETTING: Forsyth County, North Carolina; Sacramento County, California; Washington County, Maryland; and Allegheny County, Pennsylvania.

PARTICIPANTS: Community-dwelling adults aged 77 to 100 (N~=~988).

MEASUREMENTS: Serum 25-hydroxyvitamin D 25(OH)D), Short Physical Performance Battery (SPPB), and grip and knee extensor strength assessed at baseline. Mobility disability (difficulty walking half a mile or up 10 steps) and activities of daily living (ADLs) disability were assessed at baseline and every 6~months over 3~years of follow-up.

RESULTS: Almost one-third (30.8\%) of participants were deficient in 25(OH)D (<20~ng/mL). SPPB scores were lower in those with deficient 25(OH)D (mean (standard error) 6.53~(0.24)) than in those with sufficient 25(OH)D (>=30~ng/mL) (7.15~(0.25)) after adjusting for sociodemographic characteristics, season, health behaviors, and chronic conditions (P~=~.006). Grip strength adjusted for body size was also lower in those with deficient 25(OH)D than in those with sufficient 25(OH)D (24.7~(0.6)~kg vs 26.0~(0.6)~kg, P~=~.02). Participants with deficient 25(OH)D were more likely to have prevalent mobility (OR~=~1.44, 95\% confidence interval (CI))~=~0.96-2.14) and ADL disability (OR~=~1.51, 95\% CI~=~1.01-2.25) at baseline than those with sufficient 25(OH)D. Furthermore, participants with deficient 25(OH)D were at greater risk of incident mobility disability over 3~years of follow-up (hazard ratio~=~1.56, 95\% CI~=~1.06-2.30).

CONCLUSION: Vitamin D deficiency was common and was associated with poorer physical performance, lower muscle strength, and prevalent mobility and ADL disability in community-dwelling older adults. Moreover, vitamin D deficiency predicted incident mobility disability.

}, keywords = {Activities of Daily Living, Aged, Aged, 80 and over, Female, Follow-Up Studies, Geriatric Assessment, Health Surveys, Humans, Male, Mobility Limitation, Muscle Strength, Physical Fitness, Proportional Hazards Models, Reference Values, United States, Vitamin D, Vitamin D Deficiency}, issn = {1532-5415}, doi = {10.1111/j.1532-5415.2011.03601.x}, author = {Houston, Denise K and Tooze, Janet A and Davis, Cralen C and Chaves, Paulo H M and Hirsch, Calvin H and Robbins, John A and Arnold, Alice M and Newman, Anne B and Kritchevsky, Stephen B} } @article {1334, title = {Slower gait, slower information processing and smaller prefrontal area in older adults.}, journal = {Age Ageing}, volume = {41}, year = {2012}, month = {2012 Jan}, pages = {58-64}, abstract = {

BACKGROUND: Slower gait in older adults is related to smaller volume of the prefrontal area (PFAv). The pathways underlying this association have not yet been explored. Understanding slowing gait could help improve function in older age. We examine whether the association between smaller PFAv and slower gait is explained by lower performance on numerous neuropsychological tests.

HYPOTHESIS: We hypothesise that slower information processing explains this association, while tests of language or memory will not.

METHODS: Data on brain imaging, neuropsychological tests (information processing speed, visuospatial attention, memory, language, mood) and time to walk 15 feet were obtained in 214 adults (73.3 years, 62\% women) free from stroke and dementia. Covariates included central (white matter hyperintensities, vision) and peripheral contributors of gait (vibration sense, muscle strength, arthritis, body mass index), demographics (age, race, gender, education), as well as markers of prevalent vascular diseases (cardiovascular disease, diabetes and ankle arm index).

RESULTS: In linear regression models, smaller PFAv was associated with slower time to walk independent of covariates. This association was no longer significant after adding information processing speed to the model. None of the other neuropsychological tests significantly attenuated this association.

CONCLUSIONS: We conclude that smaller PFAv may contribute to slower gait through slower information processing. Future longitudinal studies are warranted to examine the casual relationship between focal brain atrophy with slowing in information processing and gait.

}, keywords = {Affect, Aged, Aged, 80 and over, Aging, Attention, Body Mass Index, Cross-Sectional Studies, Female, Gait Disorders, Neurologic, Geriatric Assessment, Humans, Male, Memory, Mental Disorders, Mental Processes, Muscle Strength, Neuroimaging, Neuropsychological Tests, Prefrontal Cortex, Prevalence, Walking}, issn = {1468-2834}, doi = {10.1093/ageing/afr113}, author = {Rosano, Caterina and Studenski, Stephanie A and Aizenstein, Howard J and Boudreau, Robert M and Longstreth, William T and Newman, Anne B} } @article {6560, title = {Disability and recovery of independent function in obstructive lung disease: the cardiovascular health study.}, journal = {Respiration}, volume = {88}, year = {2014}, month = {2014}, pages = {329-38}, abstract = {

BACKGROUND: Chronic obstructive lung disease frequently leads to disability. Older patients may experience transitions between states of disability and independence over time.

OBJECTIVE: To identify factors associated with transition between states of disability and independent function in obstructive lung disease.

METHODS: We analyzed data on 4,394 participants in the Cardiovascular Health Study who completed prebronchodilator spirometry. We calculated the 1-year probability of developing and resolving impairment in >=1 instrumental activity of daily living (IADL) or >=1 activity of daily living (ADL) using transition probability analysis. We identified factors associated with resolving disability using relative risk (RR) regression.

RESULTS: The prevalence of IADL impairment was higher with moderate (23.9\%) and severe (36.9\%) airflow obstruction compared to normal spirometry (22.5\%; p < 0.001). Among participants with severe airflow obstruction, 23.5\% recovered independence in IADLs and 40.5\% recovered independence in ADLs. In the adjusted analyses, airflow obstruction predicted the development of IADL, but not ADL impairment. Participants with severe airflow obstruction were less likely to resolve IADL impairment [RR 0.67 and 95\% confidence interval (CI) 0.49-0.94]. Compared to the most active individuals (i.e. who walked >=28 blocks per week), walking less was associated with a decreased likelihood of resolving IADL impairment (7-27 blocks: RR 0.81 and 95\% CI 0.69-0.86 and <7 blocks: RR 0.73 and 95\% CI 0.61-0.86). Increased strength (RR 1.16 and 95\% CI 1.05-1.29) was associated with resolving IADL impairment.

CONCLUSIONS: Disability is common in older people, especially in those with severe airflow obstruction. Increased physical activity and muscle strength are associated with recovery. Research is needed on interventions to improve these factors among patients with obstructive lung disease and disability.

}, keywords = {Activities of Daily Living, Aged, Cardiac Rehabilitation, Cardiovascular Diseases, Disability Evaluation, Exercise Test, Female, Humans, Independent Living, Longitudinal Studies, Male, Motor Activity, Muscle Strength, Outcome Assessment (Health Care), Pulmonary Disease, Chronic Obstructive, Recovery of Function, Risk Assessment, Severity of Illness Index, Spirometry, United States}, issn = {1423-0356}, doi = {10.1159/000363772}, author = {Fan, Vincent S and Locke, Emily R and Diehr, Paula and Wilsdon, Anthony and Enright, Paul and Yende, Sachin and Avdalovic, Mark and Barr, Graham and Kapur, Vishesh K and Thomas, Rachel and Krishnan, Jerry A and Lovasi, Gina and Thielke, Stephen} }