Suzanne Satterfield

The University of Tennessee Health Science Center, Memphis, Tennessee, United States

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Publications (197)1397.16 Total impact

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    ABSTRACT: Elevated levels of the phosphate-regulating hormone fibroblast growth factor 23 (FGF23) have been linked to greater risk of fractures in some studies, especially among individuals with chronic kidney disease (CKD). We evaluated FGF23 as a risk factor for bone loss and fractures in the Health, Aging, and Body Composition (Health ABC) study, which is a prospective biracial cohort of well-functioning adults aged 70 to 79 years recruited at two clinical centers in the United States. The sample for the bone mineral density (BMD) analysis consisted of 2234 participants who had at least two serial total hip areal BMD measures. The fracture analysis included 2786 participants, 567 of whom sustained a fracture during a median follow up of 4.95 years. Linear mixed-effects models were used for longitudinal measurements of total hip areal BMD and the proportional subdistribution hazard regression model subject to competing risks of death was used for risk of fracture. The median FGF23 was 46.7 (interquartile range [IQR] 36.7-60.2) pg/mL. The mean annualized percent change in total hip areal BMD did not vary significantly according to FGF23 quartile in all participants (P for trend = 0.70), but the effect was modified by CKD status (adjusted P for interaction < 0.001). Among participants with CKD, the unadjusted mean annualized percent change in total hip areal BMD was greater with higher levels of FGF23 (unadjusted P for trend = 0.02), but the trend was attenuated with adjustment for estimated glomerular filtration rate and parathyroid hormone (adjusted P for trend = 0.30). FGF23 was not significantly associated with fracture risk in crude (hazard ratio [HR] per doubling of FGF23, 0.97; 95%CI 0.85-1.12) or adjusted models (HR per doubling of FGF23, 1.02; 95%CI 0.86-1.22), and these findings were not modified by gender or CKD status. FGF23 levels are not associated with bone loss or fracture risk in older adults with low prevalence of CKD. This article is protected by copyright. All rights reserved.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 11/2015; DOI:10.1002/jbmr.2750 · 6.83 Impact Factor
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    ABSTRACT: Objective: We aimed to determine whether hearing impairment (HI) in older adults is associated with the development of frailty and falls. Method: Longitudinal analysis of observational data from the Health, Aging and Body Composition study of 2,000 participants aged 70 to 79 was conducted. Hearing was defined by the pure-tone-average of hearing thresholds at 0.5, 1, 2, and 4 kHz in the better hearing ear. Frailty was defined as a gait speed of <0.60 m/s and/or inability to rise from a chair without using arms. Falls were assessed annually by self-report. Results: Older adults with moderate-or-greater HI had a 63% increased risk of developing frailty (adjusted hazard ratio [HR] = 1.63, 95% confidence interval [CI] = [1.26, 2.12]) compared with normal-hearing individuals. Moderate-or-greater HI was significantly associated with a greater annual percent increase in odds of falling over time (9.7%, 95% CI = [7.0, 12.4] compared with normal hearing, 4.4%, 95% CI = [2.6, 6.2]). Discussion: HI is independently associated with the risk of frailty in older adults and with greater odds of falling over time.
    Journal of Aging and Health 10/2015; DOI:10.1177/0898264315608730 · 1.56 Impact Factor
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    ABSTRACT: Background: Inflammation, slow gait, and depression individually are associated with mortality, yet little is known about the trajectories of these measures, their interrelationships, or their collective impact on mortality. Methods: Longitudinal latent class analysis was used to evaluate trajectories of depression (Center for Epidemiologic Studies Depression ≥ 10), slow gait (<1.0 m/s), and elevated inflammation (interleukin 6 > 3.2 pg/mL) using data from the Health Aging and Body Composition Study. Logistic regression was used to identify their associations with mortality. Results: For each outcome, low-probability (n inflammation = 1,656, n slow gait = 1,471, n depression = 1,458), increasing-probability (n inflammation = 847, n slow gait = 880, n depression = 1,062), and consistently high-probability (n inflammation = 572, n slow gait = 724, n depression = 555) trajectories were identified, with 22% of all participants classified as having increasing or consistently high-probability trajectories on inflammation, slow gait, and depression (meaning probability of impairment on each outcome increased from low to moderate/high or remained high over 10 years). Trajectories of slow gait were associated with inflammation (r = .40, p < .001) and depression (r = .49, p < .001). Although worsening trajectories of inflammation were independently associated with mortality (p < .001), the association between worsening trajectories of slow gait and mortality was only present in participants with worsening depression trajectories (p < .01). Participants with increasing/consistently high trajectories of depression and consistently high trajectories of inflammation and slow gait (n = 247) have an adjusted-morality rate of 85.2%, greater than all other classification permutations. Conclusions: Comprehensive assessment of older adults is warranted for the development of treatment strategies targeting a high-mortality risk phenotype consisting of inflammation, depression, and slow gait speed.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 09/2015; DOI:10.1093/gerona/glv156 · 5.42 Impact Factor
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    ABSTRACT: Unlabelled: Obesity is a well-recognized risk factor for atrial fibrillation (AF), yet adiposity measures other than body mass index (BMI) have had limited assessment in relation to AF risk. We examined the associations of adiposity measures with AF in a biracial cohort of older adults. Given established racial differences in obesity and AF, we assessed for differences by black and white race in relating adiposity and AF. Methods: We analyzed data from 2,717 participants of the Health, Aging, and Body Composition Study. Adiposity measures were BMI, abdominal circumference, subcutaneous and visceral fat area, and total and percent fat mass. We determined the associations between the adiposity measures and 10-year incidence of AF using Cox proportional hazards models and assessed for their racial differences in these estimates. Results: In multivariable-adjusted models, 1-SD increases in BMI, abdominal circumference, and total fat mass were associated with a 13% to 16% increased AF risk (hazard ratio [HR] 1.14, 95% CI 1.02-1.28; HR 1.16, 95% CI 1.04-1.28; and HR 1.13, 95% CI 1.002-1.27). Subcutaneous and visceral fat areas were not significantly associated with incident AF. We did not identify racial differences in the associations between the adiposity measures and AF. Conclusion: Body mass index, abdominal circumference, and total fat mass are associated with risk of AF for 10years among white and black older adults. Obesity is one of a limited number of modifiable risk factors for AF; future studies are essential to evaluate how obesity reduction can modify the incidence of AF.
    American heart journal 09/2015; 170(3):498-505.e2. DOI:10.1016/j.ahj.2015.06.007 · 4.46 Impact Factor
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    ABSTRACT: Objectives: To determine whether lower extremity sensorimotor peripheral nerve deficits are associated with reduced walking endurance in older adults. Design: Prospective cohort study with 6 years of follow-up. Setting: Two university research clinics. Participants: Community-dwelling older adults enrolled in the Health, Aging and Body Composition Study from the 2000-2001 annual clinical examination (N=2393; mean age ± SD, 76.5±2.9y; 48.2% men; 38.2% black) and a subset with longitudinal data (n=1178). Interventions: Not applicable. Main outcome measures: Participants underwent peripheral nerve function examination in 2000-2001, including peroneal motor nerve conduction amplitude and velocity, vibration perception threshold, and monofilament testing. Symptoms of lower extremity peripheral neuropathy included numbness or tingling and sudden stabbing, burning, pain, or aches in the feet or legs. The Long Distance Corridor Walk (LDCW) (400m) was administered in 2000-2001 and every 2 years afterward for 6 years to assess endurance walking performance over time. Results: In separate, fully adjusted linear mixed models, poor vibration threshold (>130μm), 10-g and 1.4-g monofilament insensitivity were each associated with a slower 400-m walk completion time (16.0s, 14.4s, and 6.9s slower, respectively; P<.05 for each). Poor motor amplitude (<1mV), poor vibration perception threshold, and 10-g monofilament insensitivity were related to greater slowing per year (4.7, 4.2, and 3.8 additional seconds per year, respectively; P<.05), although poor motor amplitude was not associated with initial completion time. Conclusions: Poorer sensorimotor peripheral nerve function is related to slower endurance walking and greater slowing longitudinally. Interventions to reduce the burden of sensorimotor peripheral nerve function impairments should be considered to help older adults maintain walking endurance-a critical component for remaining independent in the community.
    Archives of physical medicine and rehabilitation 09/2015; DOI:10.1016/j.apmr.2015.08.423 · 2.57 Impact Factor
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    ABSTRACT: Evidence of the association between chronic inflammation and the risk of colorectal cancer (CRC) and other obesity-related cancers (OBRC) remains inconsistent, possibly due to a paucity of studies examining repeated measures of inflammation. In the Health ABC prospective study of 2490 adults aged 70–79 years at baseline, we assessed whether circulating levels of three markers of systemic inflammation, IL-6, CRP and TNF-α, were associated with the risk of CRC and OBRC, a cluster including cancers of pancreas, prostate, breast and endometrium. Inflammatory markers were measured in stored fasting blood samples. While only baseline measures of TNF-α were available, IL-6 and CRP were additionally measured at Years 2, 4, 6 and 8. Multivariable Cox models were fit to determine whether tertiles and log-transformed baseline, updated and averaged measures of CRP and IL-6 and baseline measures of TNF-α were associated with the risk of incident cancer(s). During a median follow-up of 11.9 years, we observed 55 and 172 cases of CRC and OBRC, respectively. The hazard of CRC in the highest tertile of updated CRP was more than double that in the lowest tertile (HR = 2.29; 95% CI: 1.08–4.86). No significant associations were seen between colorectal cancer and IL-6 or TNF-α. Additionally, no significant associations were found between obesity-related cancers and the three inflammatory markers overall, but we observed a suggestion of effect modification by BMI and NSAID use. In summary, in this population, higher CRP levels were associated with increased risk of CRC, but not of OBRC. The findings provide new evidence that chronically-elevated levels of CRP, as reflected by repeated measures of this marker, may play a role in colorectal carcinogenesis in older adults. This article is protected by copyright. All rights reserved.
    International Journal of Cancer 09/2015; DOI:10.1002/ijc.29868 · 5.09 Impact Factor
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    ABSTRACT: Functional independence with aging is an important goal for individuals and society. Simple prognostic indicators can inform health promotion and care planning, but evidence is limited by heterogeneity in measures of function. We performed a pooled analysis of data from seven studies of 27,220 community-dwelling older adults aged 65 or older with baseline gait speed, followed for disability and mortality. Outcomes were incident inability or dependence on another person in bathing or dressing; and difficulty walking ¼ - ½ mile or climbing 10 steps within 3 years. Participants with faster baseline gait had lower rates of incident disability. In subgroups (defined by 0.2 m/s-wide intervals from <0.4 to ≥1.4 m/s) with increasingly greater gait speed, 3-year rates of bathing or dressing dependence trended from 10% to 1% in men, and from 15% to 1% in women, while mobility difficulty trended from 47% to 4% in men and 40% to 6% in women. The age-adjusted relative risk ratio per 0.1 m/s greater speed for bathing or dressing dependence in men was 0.68 (0.57-0.81) and in women: 0.74 (0.66-0.82); for mobility difficulty, men: 0.75 (0.68-0.82), women: 0.73 (0.67-0.80). Results were similar for combined disability and mortality. Effects were largely consistent across subgroups based on age, gender, race, body mass index, prior hospitalization, and selected chronic conditions. In the presence of multiple other risk factors for disability, gait speed significantly increased the area under the receiver operator characteristic curve. In older adults, gait speed predicts 3 year incidence of bathing or dressing dependence, mobility difficulty, and a composite outcome of disability and mortality. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail:
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 08/2015; DOI:10.1093/gerona/glv126 · 5.42 Impact Factor
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    ABSTRACT: Depression and disability are closely linked. Less is known regarding clinical and subclinical depressive symptoms over time and risk of disability and mortality. Responses to the Center for Epidemiologic Studies Short Depression scale (CES-D10) were assessed over a 4-year period in men (n = 1032) and women (n = 1070) aged 70-79 years initially free from disability. Depressive symptom trajectories were defined with group-based models. Disability (2 consecutive reports of severe difficulty walking one-quarter mile or climbing 10 steps) and mortality were determined for 9 subsequent years. Hazard ratios (HRs) were estimated using Cox proportional hazards adjusted for covariates. Three trajectories were identified: persistently nondepressed (54% of men, 54% of women, mean baseline CES-D10: 1.16 and 1.46), mildly depressed and increasing (40% of men, 38% of women, mean baseline CES-D10: 3.60 and 4.35), and depressed and increasing (6% of men, 8% of women, mean baseline CES-D10: 7.44 and 9.61). Disability and mortality rates per 1,000 person years were 41.4 and 60.3 in men and 45.8 and 41.9 in women. Relative to nondepressed, men in the mildly depressed (HR = 1.45, 95% confidence interval [CI] 1.11-1.89) and depressed trajectories (HR = 2.12, 95% CI 1.33-3.38) had increased disability; women in the depressed trajectory had increased disability (HR = 2.02, 95% CI 1.37-2.96). Men in the mildly depressed (HR = 1.24, 95% CI 1.01-1.52) and depressed trajectories (HR = 1.63, 95% CI 1.10-2.41) had elevated mortality risk; women exhibited no mortality risk. Trajectories of depressive symptoms without recovery may predict disability and mortality in apparently healthy older populations, thus underscoring the importance of monitoring depressive symptoms in geriatric care. Published by Oxford University Press on behalf of the Gerontological Society of America 2015.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 08/2015; DOI:10.1093/Gerona/glv139 · 5.42 Impact Factor
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    ABSTRACT: Objectives To determine the association between hearing impairment (HI) and risk and duration of hospitalization in community-dwelling older adults in the United States.DesignProspective observational study.SettingHealth, Aging and Body Composition Study.ParticipantsWell-functioning community-dwelling white and black Medicare beneficiaries aged 70 to 79 at study enrollment in 1997–98 were followed for a median of 12 years.MeasurementsIncidence, annual rate, and duration of hospitalization were the primary outcomes. Hearing was defined as the pure-tone average (PTA) of hearing thresholds in decibels re: hearing level (dB HL) at octave frequencies from 0.5 to 4.0 kHz. Mild HI was defined as a PTA from 25 to 40 dB HL, and moderate or greater HI was defined as a PTA greater than 40 dB HL.ResultsOf the 2,148 participants included in the analysis, 1,801 (83.5%) experienced one or more hospitalizations, with 7,007 adjudicated hospitalization events occurring during the study period. Eight hundred eighty-two (41.1%) participants had normal hearing, 818 (38.1%) had mild HI, and 448 (20.9%) had moderate or greater HI. After adjusting for demographic characteristics and cardiovascular comorbidities, persons with mild HI experienced a 16% (hazard ratio (HR) = 1.16, 95% confidence interval (CI) = 1.04–1.29) greater risk of incident hospitalization and a 17% (incidence rate ratio (IRR) = 1.17, 95% CI = 1.04–1.32) greater annual rate of hospitalization, and those with moderate or greater HI experienced a 21% (HR = 1.21, 95% CI = 1.06–1.38) greater risk of incident hospitalization and a 19% (IRR = 1.19, 95% CI = 1.04–1.38) greater annual rate of hospitalization than persons with normal hearing. There was no significant association between HI and mean duration of hospitalization.Conclusion Hearing-impaired older adults experience a greater incidence and annual rate of hospitalization than those with normal hearing. Investigating whether rehabilitative therapies could affect the risk of hospitalization in older adults requires further study.
    Journal of the American Geriatrics Society 06/2015; 63(6):1146-1152. DOI:10.1111/jgs.13456 · 4.57 Impact Factor
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    ABSTRACT: Background: Despite a lower prevalence of established atrial fibrillation (AF) risk factors, Whites exhibit substantially higher rates of this arrhythmia compared to Blacks. The mechanism underlying this observation is not known. Both inflammation and obesity are risk factors for AF, and adipose tissue is a known contributor to systemic inflammation. Objectives: We sought to determine the degree to which racial differences in AF risk are explained by differences in inflammation and adiposity. Methods: Baseline serum inflammatory biomarker concentrations and abdominal adiposity (assessed by computed tomography) were quantified in a subset of Black and White participants without prevalent AF in the Health, Aging, and Body Composition (Health ABC) Study. Participants were prospectively followed for the diagnosis of AF using study ECGs and Medicare claims data. Cox proportional hazards models were used to determine the adjusted relative hazard of incident AF between races before and after biomarker adjustment. Results: Among 2,768 participants (43% Black), 721 developed incident AF over a median follow up of 10.9 years. White race was associated with a heightened adjusted risk of incident AF (HR 1.55, 95% CI 1.30 to 1.84, p < 0.001). Abdominal adiposity was not associated with AF when added to the adjusted model. Among the studied biomarkers, adiponectin, TNF-α, TNF-α SR I, and TNF-α SR II concentrations were each higher among Whites and independently associated with a greater risk of incident AF. Together, these inflammatory cytokines mediated 42% (95% CI 15 to 119%, p = 0.004) of the adjusted race-AF association. Conclusions: Systemic inflammatory pathways significantly mediate the heightened risk of AF among Whites. The higher level of systemic inflammation and concomitant increased AF risk in Whites is not explained by racial differences in abdominal adiposity or the presence of other pro-inflammatory cardiovascular comorbidities.
    JACC Clinical Electrophysiology 06/2015; 1(4). DOI:10.1016/j.jacep.2015.04.014
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    ABSTRACT: The objective of this study is to examine the relationship of serum carboxymethyl-lysine (CML), an advanced glycation end product (AGE), with pulse pressure (PP), aortic pulse wave velocity (aPWV) and hypertension in older adults. AGEs are bioactive molecules that accumulate in tissues with ageing and can both cross-link collagen and induce inflammation in model systems. The relationship of AGEs with arterial stiffness and hypertension has not been well characterized in community-dwelling older adults. We measured serum CML and blood pressure in 3044 adults, aged 70-79 years, who participated in the Health, Aging and Body Composition Study, a population-based study of ageing in Pittsburgh, Pennsylvania and Memphis, Tennessee. aPWV was measured in 2468 participants. Participants in the highest tertile of serum CML had higher PP (highest tertile: beta = 2.85, SE = 0.82, P = 0.0005; middle tertile: beta = 0.60, SE = 0.80, P = 0.45), and higher aPWV (highest tertile: beta = 51.4, SE = 20.1, P = 0.01; middle tertile: beta = 3.2, SE = 19.8, P = 0.87) than those in the lowest tertile in multivariable linear regression models adjusting for age, sex, race, education, BMI, smoking, alcohol use, total cholesterol, high-density lipoprotein (HDL) cholesterol, diabetes, cardiovascular disease and chronic kidney disease. Participants in the highest and middle tertiles of serum CML had higher odds of hypertension [odds ratio (OR) 1.32, 95% confidence interval (95% CI) 1.06-1.60, P = 0.005; OR 1.27, 95% CI 1.05-1.53, P = 0.01, respectively] than those in the lowest tertile in a multivariable logistic regression model adjusting for the same covariates. Elevated serum CML was associated with arterial stiffness, as reflected by higher PP and aPWV, in older, community-dwelling adults.
    Journal of Hypertension 04/2015; 33(4):797-803. DOI:10.1097/HJH.0000000000000460 · 4.72 Impact Factor

  • Journal of the American Geriatrics Society 03/2015; 63(3). DOI:10.1111/jgs.13291 · 4.57 Impact Factor
  • June Lunney · Steven Albert · Diane Ives · Anne Newman · Suzanne Satterfield ·

    Journal of Pain and Symptom Management 02/2015; 49(2):332-333. DOI:10.1016/j.jpainsymman.2014.11.034 · 2.80 Impact Factor
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    ABSTRACT: Mid-thigh cross-sectional muscle area (CSA), muscle attenuation, and greater trochanter soft tissue thickness have been shown to be independent risk factors of hip fracture. Our aim was to determine whether muscle and adipose tissue measures derived from DXA scans would have a similar risk association as those measured using other imaging methods. Using a case-cohort study design, we identified 169 incident hip fracture cases over an average of 13.5 years among participants from the Health ABC Study, a prospective study of 3,075 individuals initially aged 70-79. We modeled the thigh 3D geometry and compared DXA and CT measures. DXA-derived thigh CSA, muscle attenuation, and subcutaneous fat thickness were found to be highly correlated to their CT counterparts (Pearson's r = 0.82, 0.45, and 0.91, respectively; p < 0.05). The fracture risk of men and women were calculated separately. We found that decreased subcutaneous fat, CT thigh muscle attenuation, and appendicular lean mass by height squared (ALM/Ht2) were associated with fracture risk in men, hazard ratios (HR) equal 1.44 (1.02, 2.02), 1.40 (1.05, 1.85), and 0.58 (0.36, 0.91) respectively after adjusting for age, race, clinical site, BMI, chronic disease, hip BMD, self-reported health, alcohol use, smoking status, education, physical activity, cognitive function. In a similar model for women, only decreases in subcutaneous fat and DXA CSA were associated with hip fracture risk, HR equal 1.39 (1.07, 1.82) and 0.78 (0.62, 0.97) respectively. Men with a high ALM/Ht2 and low subcutaneous fat thickness had over 8 times higher risk for hip fracture compared to those with low ALM/Ht2 and high subcutaneous fat. In women, ALM/Ht2 did not improve the model when subcutaneous fat included. We conclude that the DXA-derived subcutaneous fat thickness is a strong marker for hip fracture risk in both men and women, and especially men with high ALM/Ht2. This article is protected by copyright. All rights reserved
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 01/2015; 30(8). DOI:10.1002/jbmr.2469 · 6.83 Impact Factor
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    ABSTRACT: We sought to develop and validate a risk index for prospective cognitive decline in older adults based on blood-derived markers. The index was based on 8 markers that have been previously associated with cognitive aging: APOE genotype, plasma β-amyloid 42/40 ratio, telomere length, cystatin C, glucose, C-reactive protein, interleukin-6, and albumin. The outcome was person-specific cognitive slopes (Modified Mini-Mental State Examination) from 11 years of follow-up. A total of 1,445 older adults comprised the development sample. An index based on dichotomized markers was divided into low-, medium-, and high-risk categories; the risk categories were validated with the remaining sample (n = 739) using linear regression. Amyloid was measured on a subsample (n = 865) and was included only in a secondary index. The risk categories showed significant differences from each other and were predictive of prospective cognitive decline in the validation sample, even after adjustment for age and baseline cognitive score: the low-risk group (24.8%) declined 0.32 points/y (95% confidence interval [CI]: -0.46, -0.19), the medium-risk group (58.7%) declined 0.55 points/y (95% CI: -0.65, 0.45), and the high-risk group (16.6%) declined 0.69 points/y (95% CI: -0.85, -0.54). Using the secondary index, which included β-amyloid 42/40 (validation n = 279), the low-risk group (26.9%) declined 0.20 points/y (95% CI: -0.42, 0.01), the medium-risk group (61.3%) declined 0.55 points/y (95% CI: -0.72, -0.38), and the high-risk group (11.8%) declined 0.83 points/y (95% CI: -1.14, -0.51). A risk index based on 8 blood-based markers was modestly able to predict cognitive decline over an 11-year follow-up. Further validation in other cohorts is necessary. © 2015 American Academy of Neurology.
    Neurology 01/2015; 84(7). DOI:10.1212/WNL.0000000000001263 · 8.29 Impact Factor
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    ABSTRACT: Apolipoprotein E (APOE) ε4 is an established risk factor for cognitive decline and the development of dementia, but other factors may help to minimize its effects. Using APOE ε4 as an indicator of high risk, we investigated factors associated with cognitive resilience among black and white older adults who are APOE ε4 carriers. Participants included 2487 community-dwelling older (aged 69-80 years at baseline) black and white adults examined at 2 community clinics in the prospective cohort Health, Aging, and Body Composition (Health ABC) study. The baseline visits occurred from May 1997 through June 1998. Our primary analytic cohort consisted of 670 APOE ε4 carriers (329 black and 341 white participants) who were free of cognitive impairment at baseline and underwent repeated cognitive testing during an 11-year follow-up (through 2008) using the Modified Mini-Mental State Examination. We stratified all analyses by race. Using the Modified Mini-Mental State Examination scores, we assessed normative cognitive change in the entire cohort (n = 2487) and classified the APOE ε4 carriers as being cognitively resilient vs nonresilient by comparing their cognitive trajectories with those of the entire cohort. We then conducted bivariate analyses and multivariable random forest and logistic regression analyses to explore factors predictive of cognitive resilience in APOE ε4 carriers. Among white APOE ε4 carriers, the strongest predictors of cognitive resilience were, in relative order of importance, no recent negative life events, a higher literacy level, advanced age, a higher educational level, and more time spent reading. Among black APOE ε4 carriers, the strongest predictors of cognitive resilience were, in relative order of importance, a higher literacy level, a higher educational level, female sex, and the absence of diabetes mellitus. In follow-up logistic regression models, higher literacy level (adjusted odds ratio [OR], 9.50 [95% CI, 2.67-60.89]), a higher educational level (adjusted OR for college graduate vs less than high school, 3.81 [95% CI, 1.13-17.56]), and age (adjusted OR for 73-76 vs 69-72 years, 2.01 [95% CI, 1.13-3.63]) had significant independent effects in predicting cognitive resilience among white APOE ε4 carriers. Among black APOE ε4 carriers, a higher literacy level (adjusted OR, 2.27 [95% CI, 1.29-4.06]) and a higher educational level (adjusted OR for high school graduate/some college vs less than high school, 2.86 [95% CI, 1.54-5.49]; adjusted OR for college graduate vs less than high school, 2.52 [95% CI, 1.14-5.62]) had significant independent effects in predicting cognitive resilience. Although APOE ε4 carriers are at high risk for cognitive decline, our findings suggest possible intervention targets, including the enhancement of cognitive reserve and improvement of other psychosocial and health factors, to promote cognitive resilience among black and white APOE ε4 carriers.
    JAMA Neurology 01/2015; 72(3). DOI:10.1001/jamaneurol.2014.3978 · 7.42 Impact Factor
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    ABSTRACT: To assess the relationship between sensorimotor nerve function and incident mobility disability over 10 years. Prospective cohort study with longitudinal analysis. Two U.S. clinical sites. Population-based sample of community-dwelling older adults with no mobility disability at 2000/01 examination (N = 1,680; mean age ± SD 76.5 ± 2.9, body mass index 27.1 ± 4.6; 50.2% female, 36.6% black, 10.7% with diabetes mellitus). Motor nerve conduction amplitude (poor <1 mV) and velocity (poor <40 m/s) were measured on the deep peroneal nerve. Sensory nerve function was measured using 10- and 1.4-g monofilaments and vibration detection threshold at the toe. Lower extremity symptoms included numbness or tingling and aching or burning pain. Incident mobility disability assessed semiannually over 8.5 years (interquartile range 4.5-9.6 years) was defined as two consecutive self-reports of a lot of difficulty or inability to walk one-quarter of a mile or climb 10 steps. Nerve impairments were detected in 55% of participants, and 30% developed mobility disability. Worse motor amplitude (HR = 1.29 per SD, 95% CI = 1.16-1.44), vibration detection threshold (HR = 1.13 per SD, 95% CI = 1.04-1.23), symptoms (HR = 1.65, 95% CI = 1.26-2.17), two motor impairments (HR = 2.10, 95% CI = 1.43-3.09), two sensory impairments (HR = 1.91, 95% CI = 1.37-2.68), and three or more nerve impairments (HR = 2.33, 95% CI = 1.54-3.53) predicted incident mobility disability after adjustment. Quadriceps strength mediated relationships between certain nerve impairments and mobility disability, although most remained significant. Poor sensorimotor nerve function independently predicted mobility disability. Future work should investigate modifiable risk factors and interventions such as strength training for preventing disability and improving function in older adults with poor nerve function. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.
    Journal of the American Geriatrics Society 12/2014; 62(12). DOI:10.1111/jgs.13152 · 4.57 Impact Factor
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    ABSTRACT: Identifying factors associated with functional declines in older adults is important given the aging of the population. We investigated if hearing impairment is independently associated with objectively measured declines in physical functioning in a community-based sample of older adults. Prospective observational study of 2,190 individuals from the Health, Aging, and Body Composition study. Participants were followed annually for up to 11 visits. Hearing was measured with pure-tone audiometry. Physical functioning and gait speed were measured with the Short Physical Performance Battery (SPPB). Incident disability and requirement for nursing care were assessed semiannually through self-report. In a mixed-effects model, greater hearing impairment was associated with poorer physical functioning. At both Visit 1 and Visit 11, SPPB scores were lower in individuals with mild (10.14 [95% CI 10.04-10.25], p < .01; 7.35 [95% CI 7.12-7.58], p < .05) and moderate or greater hearing impairment (10.04 [95% CI 9.90-10.19], p < .01; 7.00 [95% CI 6.69-7.32], p < .01) than scores in normal hearing individuals (10.36 [95% CI 10.26-10.46]; 7.71 [95% CI 7.49-7.92]). We observed that women with moderate or greater hearing impairment had a 31% increased risk of incident disability (Hazard ratio [HR] =1.31 [95% CI 1.08-1.60], p < .01) and a 31% increased risk of incident nursing care requirement (HR = 1.31 [95% CI 1.05-1.62], p = .02) compared to women with normal hearing. Hearing impairment is independently associated with poorer objective physical functioning in older adults, and a 31% increased risk for incident disability and need for nursing care in women. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail:
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 12/2014; 70(5). DOI:10.1093/gerona/glu207 · 5.42 Impact Factor
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    ABSTRACT: Objectives To examine the association between statin use and objectively assessed decline in gait speed in community-dwelling older adults.DesignLongitudinal cohort study.SettingHealth, Aging and Body Composition (Health ABC) Study.ParticipantsTwo thousand five participants aged 70–79 at baseline with medication and gait speed data at 1998–99, 1999–2000, 2001–02, and 2002–03.MeasurementsThe independent variables were any statin use and their standardized daily doses (low, moderate, high) and lipophilicity. The primary outcome measure was decline in gait speed of 0.1 m/s or more in the following year of statin use. Multivariable generalized estimating equations were used, adjusting for demographic characteristics, health-related behaviors, health status, and access to health care.ResultsStatin use increased from 16.2% in 1998–99 to 25.6% in 2002–03. The overall proportions of those with decline in gait speed of 0.1 m/s or more increased from 22.2% in 1998 to 23.9% in 2003. Statin use was not associated with decline in gait speed of 0.1 m/s or more (adjusted odds ratio (AOR) = 0.90, 95% confidence interval (CI) = 0.77–1.06). Similar nonsignificant trends were also seen with the use of hydrophilic or lipophilic statins. Users of low-dose statins were found to have a 22% lower risk of decline in gait speed than nonusers (AOR = 0.78, 95% CI = 0.61–0.99), which was mainly driven by the results from 1999–2000 follow-up.Conclusion These results suggest that statin use did not increase decline in gait speed in community-dwelling older adults.
    Journal of the American Geriatrics Society 12/2014; 63(1). DOI:10.1111/jgs.13134 · 4.57 Impact Factor
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    ABSTRACT: Protracted, systemic inflammation has been associated with adverse effects on cognition and brain structure, and may accelerate neurodegenerative disease processes; however, it is less clear whether changes in inflammation are associated with brain structure.Methods We studied 276 black and white older adults (mean age=83 years at time of imaging) enrolled in a prospective study of aging. Inflammation (measured with CRP) was assessed repeatedly over 6 years (i.e. Year 2, 4, 6, & 8). Brain MRIs were obtained at years 10-11 with DTI; regions of interest included late-myelinating areas vulnerable to aging, including frontal-parietal [superior longitudinal fasciculus (SLF)-dorsal] and temporal (SLF-temporal; uncinate) white matter tracts.ResultsMean CRP values significantly declined (t=-5.54, p<.0001) over 6 years, and subject-specific slopes (BLUPs) all showed a decline (mean=-.57, SD=.53) for our participant sample. More than 50% of study participants were still in the moderate to high cardiovascular risk range based on CRP values at Year 8. After controlling for demographics, vascular risk factors and MRI white matter hyperintensities, larger decreases in CRP values over time were significantly associated with higher fractional anisotropy in the SLF-dorsal [Beta=-0.0052, standard error (SE)=0.003; 95% confidence interval (CI)= -0.0103 to -0.0025, p=.04], SLF-temporal (Beta=-0.0109, SE=0.004; 95%CI=-0.0189 to -0.0029, p=.008), and uncinate (Beta=-0.0067, SE=0.003; 95%CI=-0.0132 to -0.0001, p=.05) fasciculi.Conclusions Results suggest that in a prospective cohort of older individuals, faster declines in inflammation over time are related to indicators of white matter health, even after accounting for vascular risk factors.
    Neurobiology of Aging 11/2014; 36(2). DOI:10.1016/j.neurobiolaging.2014.11.004 · 5.01 Impact Factor

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9k Citations
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  • 2007-2015
    • The University of Tennessee Health Science Center
      • • Department of Preventive Medicine
      • • Department of Medicine
      Memphis, Tennessee, United States
    • The University of Tennessee Medical Center at Knoxville
      Knoxville, Tennessee, United States
  • 1999-2015
    • University of Tennessee
      • Department of Preventive Medicine
      Knoxville, Tennessee, United States
  • 2014
    • United States Department of Veterans Affairs
      Бедфорд, Massachusetts, United States
  • 2013
    • Boston University
      • Section of Cardiovascular Medicine
      Boston, Massachusetts, United States
  • 2006-2012
    • The University of Memphis
      Memphis, Tennessee, United States
  • 2006-2011
    • University of Pittsburgh
      • Department of Epidemiology
      Pittsburgh, Pennsylvania, United States
  • 2010
    • University of Lausanne
      • Faculté de biologie et de médecine (FBM)
      Lausanne, VD, Switzerland
  • 2009
    • National Institute on Aging
      • Clinical Research Branch (CRB)
      Baltimore, Maryland, United States
  • 2008
    • Emory University
      • Division of Cardiology
      Atlanta, GA, United States
  • 2005
    • University of California, San Francisco
      • Division of Hospital Medicine
      San Francisco, California, United States
  • 1997
    • Tulane University
      • School of Public Health and Tropical Medicine
      New Orleans, Louisiana, United States
  • 1991-1994
    • Harvard Medical School
      • Department of Medicine
      Boston, Massachusetts, United States
  • 1993
    • Brigham and Women's Hospital
      • Department of Medicine
      Boston, MA, United States