Stephanie L Harrison

California Pacific Medical Center Research Institute, San Francisco, California, United States

Are you Stephanie L Harrison?

Claim your profile

Publications (20)107.08 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background. Age-related hyperkyphosis has been associated with poor physical function and is a well-established predictor of adverse health outcomes in older women, but its impact on health in older men is less well understood. Methods. We conducted a cross-sectional study to evaluate the association of hyperkyphosis and physical function in 2,363 men, aged 71–98 (M = 79) from the Osteoporotic Fractures in Men Study. Kyphosis was measured using the Rancho Bernardo Study block method. Measurements of grip strength and lower extremity function, including gait speed over 6 m, narrow walk (measure of dynamic balance), repeated chair stands ability and time, and lower extremity power (Nottingham Power Rig) were included separately as primary outcomes. We investigated associations of kyphosis and each outcome in age-adjusted and multivariable linear or logistic regression models, controlling for age, clinic, education, race, bone mineral density, height, weight, diabetes, and physical activity. Results. In multivariate linear regression, we observed a dose-related response of worse scores on each lower extremity physical function test as number of blocks increased, p for trend ≤.001. Using a cutoff of ≥4 blocks, 20% (N = 469) of men were characterized with hyperkyphosis. In multivariate logistic regression, men with hyperkyphosis had increased odds (range 1.5–1.8) of being in the worst quartile of performing lower extremity physical function tasks (p < .001 for each outcome). Kyphosis was not associated with grip strength in any multivariate analysis. Conclusions. Hyperkyphosis is associated with impaired lower extremity physical function in older men. Further studies are needed to determine the direction of causality.
    Journals of Gerontology: MEDICAL SCIENCES,. 11/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Low serum 25-hydroxy vitamin D (25(OH)D) concentrations are associated with increased hip fracture risk and decreased femoral areal bone mineral density (BMD) among elderly men. Structural dimensions of the proximal femur and volumetric BMD in cortical and trabecular compartments are also associated with hip fracture risk. However, associations of volumetric BMD or structural dimensions with serum 25(OH)D concentrations among older men remain unclear. In a random sample of 1608 men aged ≥65 years from the Osteoporotic Fractures in Men Study (MrOS), baseline serum 25(OH)D concentrations were measured by liquid chromatography/mass spectrometry assays. Femoral neck geometry and volumetric BMD derived from quantitative computed tomography included integral, cortical, and trabecular volumetric BMD; cross-sectional area; integral and cortical volume; and cortical volume as a percent of integral volume. We studied 888 men with vitamin D, parathyroid hormone (PTH), femoral neck geometry, and BMD measures. Whole-bone femoral strength and load-strength ratio from finite element (FE) analysis were also available for 356 men from this sample. Multivariable linear regression was used to estimate least square means of each femoral measure within quartiles of 25(OH)D adjusted for age, race, body mass index, height, latitude, and season of blood draw. Tests of linear trend in the means were performed across increasing quartile of serum 25(OH)D levels. Mean cortical volume (p trend = 0.006) and cortical volume as a percent of integral volume (p trend < 0.001) increased across increasing quartile of 25(OH)D level. However, overall femoral neck size (area and integral volume) did not vary by 25(OH)D level. Femoral neck volumetric BMD measures increased in a graded manner with higher 25(OH)D levels (p trend < 0.001). Femoral strength, but not load-strength ratio, increased with increasing 25(OH)D. Adjustment for PTH did not materially change these associations. We conclude that in older men, higher levels of endogenous 25(OH)D may increase whole-bone strength by increasing femoral volumetric BMD and cortical volume. 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 11/2014; · 6.04 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Hyponatremia may be a risk factor for fracture. To determine the relationship between hyponatremia and fracture we conducted cross-sectional and longitudinal analyses using data from the Osteoporotic Fractures in Men Study (MrOS). The MrOS study enrolled 5122 community dwelling men aged ≥ 65 years from six centers across the United States. We excluded men taking bisphosphonates, those with unknown medication history, those without serum sodium measures, or those with out of range assays for serum sodium. Serum sodium was measured at study entry. Subjects were followed for fractures (nonspine (including hip), hip, and incident and prevalent morphometric) for up to 9 years. We used cox proportional hazards models to analyze the association between serum sodium levels (<135mmol/L versus .135mmol/L) and risk of nonspine and hip fractures, with results presented as hazard ratios (HR) and 95% confidence intervals (CI). We examined the association between morphometric vertebral fractures and serum sodium using logistic regression models, presented as odds ratios (OR) and 95% CI. Hyponatremia was observed in 64 men (1.2% of the cohort). After adjusting for age, BMI, study center, and other covariates, we found that, compared to men with serum sodium ≥ 135mmol/L, those with serum sodium <135mmol/L, had an increased risk hip fracture (HR=3.04; 95% CI: 1.37 to 6.75), prevalent (OR=2.46; 95% CI: 1.22 to 4.95) and incident (OR=3.53; 95% CI: 1.35 to 9.19) morphometric spine fractures but not nonspine fractures (OR=1.44; 95% CI: 0.85 to 2.44). Adjusting for bone mineral density did not change our findings. Our data demonstrate that hyponatremia is associated with up to a doubling in the risk of hip and morphometric spine fractures, independent of BMD. Further studies, to determine how hyponatremia causes fractures and if correction of hyponatremia decreases fractures, are needed. © 2014 American Society for Bone and Mineral Research
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 10/2014; · 6.04 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To determine the association between objectively measured physical activity (PA), fractures, and falls. Longitudinal cohort study. Six U.S. clinical sites. Two thousand seven hundred thirty-one men with a mean age of 79. Total and active energy expenditure (EE) and minutes per day spent in sedentary and moderate intensity activities were measured for at least 5 days. Energy expended at a metabolic equivalent of greater than three was termed active EE. Incident nonspine fractures and falls were identified every 4 months. Seven hundred fifty-nine (28.2%) men fell at least once over 12 months of follow-up; 186 (6.8%) experienced one or more fractures over an average follow-up of 3.5 ± 0.9 years. The association between PA and falling varied according to age (P interaction = .02). Men younger than 80 with the lowest active EE had a lower risk of falling than men with the highest active EE (relative risk (RR) = 0.75; P trend = .08), whereas men aged 80 and older with the lowest active EE had a higher risk of falling than men with the highest active EE (RR = 1.43, P trend = .09). In multivariate models including health status, men in the lowest quintile of active EE had a significantly higher risk of fracture (hazard ratio (HR) = 1.82, 95% confidence interval (CI) = 1.10-3.00, P trend = .04) than men in highest quintile. Men with <33 min/d of moderate activity had a 70% greater risk of fracture (HR = 1.70, 95% CI = 1.03-2.80). Age modifies the association between PA and falling. Interventions aimed at obtaining more than 30 minutes of moderate PA per day may reduce fractures, extending PA guidelines to the oldest old, the fastest-growing proportion of those aged 65 and older.
    Journal of the American Geriatrics Society 07/2013; 61(7):1080-8. · 4.22 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND: The relationship between objectively assessed activity, energy expenditure, and the development of functional limitations is unknown. METHODS: Energy expenditure and activity levels were measured objectively using the multisensor SenseWear Pro Armband worn for greater than or equal to 5 days in 1,983 MrOS men (aged ≥78.3 years) free of functional limitations. Validated algorithms calculated energy expenditure; standard cut points defined moderate or greater activity (≥3.0 METS); and sedentary behavior (time awake ≤ 1.5 METS). Self-reported functional limitation was determined at the activity assessment and 2.0 years later as inability to perform instrumental activities of daily living (managing money, managing medications, shopping, housework, and meal preparation) and activities of daily living (climb stairs, walk two to three blocks, transfer, or bathe). RESULTS: Each standard deviation decrease in total energy expenditure (420.6 kcal/day) increased the likelihood of inability to perform an instrumental activity of daily living (multivariate odds ratio [mOR]: 1.61, 95% CI: 1.30-2.00) or activity of daily living (mOR: 1.35, 95% CI: 1.12-1.63). Each standard deviation decrease in moderate or greater activity (61.1 minutes/day) increased the likelihood of inability to perform an instrumental activity of daily living (mOR: 1.47, 95% CI: 1.22-1.78) or activity of daily living (mOR: 1.36, 95% CI: 1.14-1.61). Each standard deviation increase in minutes of sedentary behavior (105.2 minutes/day) increased the likelihood of inability to perform an instrumental activity of daily living (mOR: 1.20, 95% CI: 1.03-1.40) or activity of daily living (mOR: 1.17, 95% CI: 1.01-1.35). CONCLUSION: Older men with lower total energy expenditure, lower moderate activity, or greater sedentary time were more likely to develop a functional limitation.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 05/2013; · 4.31 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Assess the association between REM predominant obstructive sleep apnea (OSA), sleepiness, and quality of life in a community-based cohort of men ≥ 65 years-old. A cross-sectional analysis of 2,765 subjects from the Outcomes of Sleep Disorders in Older Men (MrOS Sleep) Study was performed to identify subjects with an apnea hypopnea index (AHI) < 15 (n = 2,044). Subjects were divided into groups based on the AHI in REM sleep (< 5 [referent group], 5 to < 15, 15 to < 30, and ≥ 30). Daytime somnolence, sleep-related quality of life, sleep disturbance, general quality of life, depressive symptoms, and health status were quantified using Epworth Sleepiness Scale (ESS), Functional Outcomes of Sleep Questionnaire (FOSQ), Pittsburgh Sleep Quality Index (PSQI), Short Form-12 (SF-12), Geriatric Depression Scale-15 (GDS), and self-perceived health status, respectively. Prevalence of REM-predominant OSA (AHI-REM ≥ 5) was 42.8% if OSA was defined as AHI ≥ 15 and 14.4% if OSA was defined as AHI ≥ 5. Higher AHI-REM was associated with polysomnographic indices of poorer sleep architecture (reduced total sleep time, sleep efficiency, REM sleep duration and proportion). Adjusting for age, BMI, and study site, higher AHI-REM was not associated with subjective sleep measures (ESS, FOSQ, PSQI), lower quality of life (SF-12), or greater depressive symptoms (GDS). In a community-based sample of older adult men ≥ 65 years-old, REM-predominant OSA was highly prevalent and was associated with objective indices of poorer sleep quality on polysomnography but not with subjective measures of daytime sleepiness or quality of life. Khan A; Harrison SL; Kezirian EJ; Ancoli-Israel S; O'Hearn D; Orwoll E; Redline S; Ensrud K; Stone KL. Obstructive sleep apnea during rapid eye movement sleep, daytime sleepiness, and quality of life in older men in osteoporotic fractures in men (MrOS) sleep study. J Clin Sleep Med 2013;9(3):191-198.
    Journal of clinical sleep medicine: JCSM: official publication of the American Academy of Sleep Medicine 01/2013; 9(3):191-198. · 2.93 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Excess thyroid hormone is associated with increased bone loss and fracture risk in older women, but few data exist in men. We sought to determine if thyroid function is independently associated with bone loss and fracture risk in older men. Data were analyzed from the Osteoporotic Fractures in Men (MrOS) Study, a cohort of community-dwelling US men aged 65 years and older. Using a case-cohort design, fasting baseline serum archived at -80C was assayed for thyrotropin (TSH) and free thyroxine (FT4) in 397 men with confirmed non-spine fracture, including 157 hip fractures, and 1420 randomly selected men without fracture. TSH and FT4 were analyzed as continuous variables and as thyroid function categories (subclinical hyperthyroid, euthyroid, and subclinical hypothyroid). Hip DXA (Hologic QDR4500) was measured at baseline and after a mean follow-up of 4.6 yr. Incident nonspine fractures were centrally adjudicated. Bone loss was evaluated with multivariate regression methods and fractures risk was evaluated using hazard models that accounted for the case-cohort sampling, adjusted for age, clinic-site, BMI, race, physical activity, corticosteroid use, smoking, alcohol intake, and thyroid medication use. In fully adjusted analyses, TSH was not associated with risk of nonspine fracture (RH 0.92 per SD decrease in TSH, 95% CI 0.74 - 1.14), but was significantly associated with risk of hip fracture (RH 1.31 [1.01 - 1.71]) which persisted among normal range TSH values (RH 1.21 [1.00 - 1.47]). There was no association between TSH or FT4 and bone loss, and fracture risk did not differ significantly by thyroid function category. We conclude that while neither TSH nor FT4 are associated with bone loss, lower serum TSH may be associated with an increased risk of hip fractures in older men. © 2012 American Society for Bone and Mineral Research.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 09/2012; · 6.04 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this prospective cohort study, depressive symptoms were associated with higher rates of bone loss in older men. Poorer performance on physical function tests partly explained the association between depressive symptoms and bone loss, suggesting that efforts to increase exercise and improve physical performance in depressed men may be beneficial. INTRODUCTION: The aim of this study was to ascertain whether depressive symptoms are associated with increased rates of bone loss at the hip in older men. METHODS: A population-based prospective cohort study of 2,464 community-dwelling men, aged 68 and older, enrolled in the Osteoporosis in Men Sleep Ancillary Study had depressive symptoms assessed by the Geriatric Depression Scale (GDS). Subjects were categorized as depressed if GDS ≥6 at the initial examination. Bone mineral density (BMD) at the hip was measured using dual-energy X-ray absorptiometry at the initial and follow-up examination (average 3.4 years between exams). Use of antidepressant medications was assessed by interview and verified from medication containers at the two examinations. A computerized dictionary was used to categorize type of medication. RESULTS: In a base model adjusted for age, race/ethnicity, and clinic site, the mean total hip BMD decreased 0.70 %/year in 136 men with a GDS score of ≥6 compared to 0.39 %/year in 2,328 men with a GDS score of <6 (p = 0.001). Walking speed and timed chair stand partly explained the association between depressive symptoms and rates of bone loss. CONCLUSION: Depression, as defined by a score of 6 or greater on the Geriatric Depression Scale, is associated with an increased rate of bone loss at the hip in this cohort of older men. Adjustment for walking speed and timed chair stand attenuated the strength of the association, suggesting that differences in physical functioning do partially explain the observed association.
    Osteoporosis International 03/2012; · 4.04 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Mild abnormalities of thyroid function have been associated with both beneficial and detrimental effects on mortality. Our objective was to determine the association between continuous TSH as well as categories of thyroid function with total and cause-specific mortality in a cohort of older men. Data were analyzed from the Osteoporotic Fractures in Men (MrOS) study, a cohort of community-dwelling U.S. men aged 65 yr and older. A total of 1587 participants randomly selected for thyroid function testing were included in this analysis. TSH and free T4 were measured at baseline, and four categories of thyroid function were defined. (subclinical hyperthyroid; euthyroid; subclinical hypothyroid TSH<10 mIU/liter; and subclinical hypothyroid, TSH≥10 mIU/liter.) Total mortality, cardiovascular (CV) and cancer deaths were confirmed by review of death certificates. There were 432 deaths over a mean follow-up of 8.3 yr. In fully adjusted models, there was no association between baseline TSH and any death [relative hazard (RH)=1.01 per mIU/liter, 95% confidence interval (CI)=0.95-1.06], CV death (RH=1.05 per mIU/liter, 95% CI 0.96-1.15), or cancer death (RH=0.96 per mIU/liter, 95% CI=0.85-1.07). There was also no statistically significant association between thyroid function category and total or cause-specific mortality, but few men (n=8) had subclinical hypothyroidism with TSH levels of 10 mIU/liter or higher. A single measurement of thyroid function did not predict total or cause-specific mortality in this cohort. These data support neither a beneficial nor a detrimental effect of subclinical thyroid dysfunction in older men. Subclinical thyroid dysfunction is not associated with an increased risk of all-cause or CV mortality in older men.
    The Journal of Clinical Endocrinology and Metabolism 03/2012; 97(3):862-70. · 6.31 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This study examined the association between race/ethnicity and objectively measured sleep characteristics in a large sample of older men. Black men had significantly shorter total sleep time (6.1 hr vs. 6.4 hr), longer sleep latency (28.7 min vs. 21.9 min), lower sleep efficiency (80.6% vs. 83.4%), and less slow-wave sleep (4.9% vs. 8.8%) than White men, even after controlling for social status, comorbidities, body mass index, and sleep-disordered breathing. Hispanic men slept longer (6.7 hr) at night than Black (6.1 hr) and Asian American men (6.1 hr). This study supports significant variations in sleep characteristics in older men by race/ethnicity.
    Behavioral Sleep Medicine 12/2011; 10(1):54-69. · 1.13 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Both subclinical hypothyroidism and the metabolic syndrome have been associated with increased risk of coronary heart disease events. It is unknown whether the prevalence and incidence of metabolic syndrome is higher as TSH levels increase, or in individuals with subclinical hypothyroidism. We sought to determine the association between thyroid function and the prevalence and incidence of the metabolic syndrome in a cohort of older adults. Data were analysed from the Health, Ageing and Body Composition Study, a prospective cohort of 3075 community-dwelling US adults. Two thousand one hundred and nineteen participants with measured TSH and data on metabolic syndrome components were included in the analysis. TSH was measured by immunoassay. Metabolic syndrome was defined per revised ATP III criteria. At baseline, 684 participants met criteria for metabolic syndrome. At 6-year follow-up, incident metabolic syndrome developed in 239 individuals. In fully adjusted models, each unit increase in TSH was associated with a 3% increase in the odds of prevalent metabolic syndrome (OR, 1.03; 95% CI, 1.01-1.06; P = 0.02), and the association was stronger for TSH within the normal range (OR, 1.16; 95% CI, 1.03-1.30; P = 0.02). Subclinical hypothyroidism with a TSH > 10 mIU/l was significantly associated with increased odds of prevalent metabolic syndrome (OR, 2.3; 95% CI, 1.0-5.0; P = 0.04); the odds of incident MetS was similar (OR 2.2), but the confidence interval was wide (0.6-7.5). Higher TSH levels and subclinical hypothyroidism with a TSH > 10 mIU/l are associated with increased odds of prevalent but not incident metabolic syndrome.
    Clinical Endocrinology 12/2011; 76(6):911-8. · 3.40 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Sleep-disordered breathing (characterized by recurrent arousals from sleep and intermittent hypoxemia) is common among older adults. Cross-sectional studies have linked sleep-disordered breathing to poor cognition; however, it remains unclear whether sleep-disordered breathing precedes cognitive impairment in older adults. To determine the prospective relationship between sleep-disordered breathing and cognitive impairment and to investigate potential mechanisms of this association. Prospective sleep and cognition study of 298 women without dementia (mean [SD] age: 82.3 [3.2] years) who had overnight polysomnography measured between January 2002 and April 2004 in a substudy of the Study of Osteoporotic Fractures. Sleep-disordered breathing was defined as an apnea-hypopnea index of 15 or more events per hour of sleep. Multivariate logistic regression was used to determine the independent association of sleep-disordered breathing with risk of mild cognitive impairment or dementia, adjusting for age, race, body mass index, education level, smoking status, presence of diabetes, presence of hypertension, medication use (antidepressants, benzodiazepines, or nonbenzodiazepine anxiolytics), and baseline cognitive scores. Measures of hypoxia, sleep fragmentation, and sleep duration were investigated as underlying mechanisms for this relationship. Adjudicated cognitive status (normal, dementia, or mild cognitive impairment) based on data collected between November 2006 and September 2008. Compared with the 193 women without sleep-disordered breathing, the 105 women (35.2%) with sleep-disordered breathing were more likely to develop mild cognitive impairment or dementia (31.1% [n = 60] vs 44.8% [n = 47]; adjusted odds ratio [AOR], 1.85; 95% confidence interval [CI], 1.11-3.08). Elevated oxygen desaturation index (≥15 events/hour) and high percentage of sleep time (>7%) in apnea or hypopnea (both measures of disordered breathing) were associated with risk of developing mild cognitive impairment or dementia (AOR, 1.71 [95% CI, 1.04-2.83] and AOR, 2.04 [95% CI, 1.10-3.78], respectively). Measures of sleep fragmentation (arousal index and wake after sleep onset) or sleep duration (total sleep time) were not associated with risk of cognitive impairment. Among older women, those with sleep-disordered breathing compared with those without sleep-disordered breathing had an increased risk of developing cognitive impairment.
    JAMA The Journal of the American Medical Association 08/2011; 306(6):613-9. · 29.98 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: S LEEP-DISORDERED BREATHING, A disorder characterized by recur-rent arousals from sleep and in-termittent hypoxemia, is com-mon among older adults and affects up to 60% of elderly populations. 1 A num-ber of adverse health outcomes includ-ing hypertension, cardiovascular dis-ease, and diabetes have been associated with sleep-disordered breathing. 2-5 Cog-nitive impairment also has been linked to sleep-disordered breathing, but the majority of studies have been cross-sectional or have relied on nonobjec-tive measures of sleep-disordered breath-ing, thus limiting the ability to draw conclusions on the directionality of the association. 6-8 It remains unclear whether sleep-disordered breathing precedes cog-nitive impairment in community-dwelling elderly individuals. Given the high prevalence and sig-nificant morbidity associated with both sleep-disordered breathing and cogni-tive impairment in older populations, es-tablishing whether a prospective asso-ciation exists between sleep-disordered breathing and cognition is important. This is especially important because ef-For editorial comment see p 654.
    Alzheimers & Dementia - ALZHEIMERS DEMENT. 01/2010; 6(4).
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In 5,541 community dwelling men, chronic obstructive pulmonary disease, or asthma was associated with lower bone mineral density (BMD) at the spine and total hip and an increased risk of vertebral and nonvertebral fractures independent of age, body mass index, and smoking. Men prescribed with corticosteroids had the lowest BMD. It is unclear whether chronic obstructive pulmonary disease (COPD) is independently associated with BMD and fractures. In 5,541 men from the Osteoporotic Fractures in Men Study, history of COPD or asthma, current treatment with corticosteroids, BMD, bone loss after 4.5 years and fractures were ascertained. Seven hundred fourteen (13%) men reported COPD or asthma, of which 103 were prescribed an oral steroid and 177 an inhaled steroid. Independent of confounders, men prescribed corticosteroids for COPD or asthma had the lowest BMD and a 2-fold increased risk of vertebral osteoporosis compared to men with no history of COPD or asthma (OR 2.13, 95% CI (confidence interval) 1.15-3.93 oral steroids; OR 2.05, 95% CI 1.27-3.31 inhaled steroids). During follow-up, BMD increased at the spine, but there was no difference in bone loss at the hip. However, men with COPD or asthma had a 2.6- and 1.4-fold increased risk of vertebral and nonvertebral fractures, respectively. Chronic obstructive pulmonary disease or asthma was associated with lower BMD at the spine and hip and increased risk of vertebral and nonvertebral fractures independent of age, clinic site, BMI, and smoking. A history of COPD or asthma may be a useful clinical risk factor to identify patients with osteoporosis.
    Osteoporosis International 10/2009; 21(8):1341-9. · 4.04 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We used data from the Osteoporotic Fractures in Men (MrOS) study to test the hypothesis that men with higher levels of bone turnover would have accelerated bone loss and an elevated risk of fracture. MrOS enrolled 5995 subjects >65 yr; hip BMD was measured at baseline and after a mean follow-up of 4.6 yr. Nonspine fractures were documented during a mean follow-up of 5.0 yr. Using fasting serum collected at baseline and stored at -190 degrees C, bone turnover measurements (type I collagen N-propeptide [PINP]; beta C-terminal cross-linked telopeptide of type I collagen [betaCTX]; and TRACP5b) were obtained on 384 men with nonspine fracture (including 72 hip fractures) and 947 men selected at random. Among randomly selected men, total hip bone loss was 0.5%/yr among those in the highest quartile of PINP (>44.3 ng/ml) and 0.3%/yr among those in the lower three quartiles (p = 0.01). Fracture risk was elevated among men in the highest quartile of PINP (hip fracture relative hazard = 2.13; 95% CI: 1.23, 3.68; nonspine relative hazard = 1.57, 95% CI: 1.21, 2.05) or betaCTX (hip fracture relative hazard = 1.76, 95 CI: 1.04, 2.98; nonspine relative hazard = 1.29, 95% CI: 0.99, 1.69) but not TRACP5b. Further adjustment for baseline hip BMD eliminated all associations between bone turnover and fracture. We conclude that higher levels of bone turnover are associated with greater hip bone loss in older men, but increased turnover is not independently associated with the risk of hip or nonspine fracture.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 06/2009; 24(12):2032-8. · 6.04 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To examine the association between sleep-disordered breathing (SDB) and subjective measures of daytime sleepiness, sleep quality, and sleep-related quality of life in a large cohort of community-dwelling older men and to determine whether any association remained after adjustment for sleep duration. Cross-sectional. The functional outcome measures of interest were daytime sleepiness (Epworth Sleepiness Scale, ESS), sleep-related symptoms (Pittsburgh Sleep Quality Index, PSQI), and sleep-related quality of life (Functional Outcomes of Sleep Questionnaire, FOSQ). Analysis of variance and adjusted regression analyses examined the association between these outcome measures and SDB severity and actigraphy-determined total sleep time (TST). We then explored whether associations with SDB were confounded by sleep duration by adjusting models for TST. Community-based sample in home and research clinic settings. Two-thousand eight-hundred forty-nine older men from the multicenter Osteoporotic Fractures in Men Study that began in 2000. All participants underwent in-home polysomnography for 1 night and wrist actigraphy for a minimum of 5 consecutive nights. N/A. Measurements and Results: Participants were aged 76.4 + 5.5 years and had an apnea-hypopnea index (AHI) of 17.0 + 15.0. AHI and TST were weakly correlated. ESS scores individually were modestly associated with AHI and TST, but the association with AHI was attenuated by adjustment for TST. PSQI and FOSQ scores were largely not associated with measures of SDB severity but were modestly associated with TST. Daytime sleepiness, nighttime sleep disturbances, and sleep-related quality of life were modestly associated with TST. After adjustment for TST, there was no independent association with SDB severity. These results underscore the potential differences in SDB functional outcomes in older versus young and middle-aged adults.
    Sleep 03/2009; 32(2):253-61. · 5.10 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Little is known about the association of low endogenous testosterone levels and abnormal sleep patterns in older men, although pharmacological doses of testosterone are associated with increased severity of sleep apnea and other sleep disturbances. The objective of the study was to examine the association between serum testosterone levels with objectively measured sleep characteristics. This was a cohort study. Community-dwelling men aged 65 yr or older from six clinical centers in the United States participated in the study. A total of 1312 men had baseline total testosterone levels measured in 2000-2002, followed 3.4 yr later by 72-h (minimum) actigraphy and one-night in-home polysomnography to assess sleep duration, sleep fragmentation, and sleep apnea. Analyses were performed by quartile of total testosterone and categorically defined low vs. higher total testosterone (<250 ng/dl vs. > or =250 ng/dl). Lifestyle and body size were covariates. Total testosterone levels were unrelated to age or duration of sleep. Men with lower testosterone levels had lower sleep efficiency, with increased nocturnal awakenings and less time in slow-wave sleep as well as a higher apnea-hypopnea index and more sleep time with O(2) saturation levels below 90%. Low testosterone levels were associated with overweight, and all significant associations were attenuated or absent after adjusting for body mass index or waist circumference. In a post hoc analysis in men with higher body mass index (>27 kg/m2), testosterone was significantly associated with more periods awake after sleep onset and lower sleep efficiency. Low total testosterone levels are associated with less healthy sleep in older men. This association is largely explained by adiposity. Clinical trials are necessary to determine whether body weight acts directly or indirectly (via low testosterone) in the causal pathway for sleep-disordered breathing in older men.
    Journal of Clinical Endocrinology &amp Metabolism 08/2008; 93(7):2602-9. · 6.43 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To examine the fracture pattern in older women whose bone mineral density (BMD) T-score criteria for osteoporosis at hip and spine disagree, hip and spine BMD were measured in Study of Osteoporotic Fractures participants using dual energy X-ray absorptiometry (DXA). Hip osteoporosis was defined as T-score <or=-2.5 at femoral neck or total hip, and spine osteoporosis as T-score <or=-2.5 at lumbar spine. Incident clinical fractures were self-reported and centrally adjudicated. Incident radiographic spine fractures were defined morphometrically. Compared to women with osteoporosis at neither hip nor spine, those osteoporotic only at hip had a 3.0-fold age- and weight-adjusted increased risk for hip fracture (95% confidence interval [CI]: 2.4-3.6), and smaller increases in risk of nonhip nonspine (hazard ratios [HR]=1.6), clinical spine (odds ratio [OR]=2.2), and radiographic spine fractures (OR=1.5). Women osteoporotic only at spine had a 2.8-fold increased odds of radiographic spine fracture (95% CI: 2.1-3.8), and smaller increases in risk of clinical spine (OR=1.4), nonhip nonspine (HR=1.6), and hip fractures (HR=1.2). Discordant BMD results predict different fracture patterns. DXA fracture risk estimation in these patients should be site specific. Women osteoporotic only at spine would not have been identified from hip BMD measurement alone, and may have a sufficiently high fracture risk to warrant preventive treatment.
    Journal of Clinical Densitometry 01/2008; 11(2):250-9. · 1.71 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To examine the association between SDB and subjective measures of daytime sleepiness, sleep quality, and sleep related quality of life in a large cohort of primarily community-dwelling older women, specifically considering the relative importance of sleep duration in mediating these associations. Cross-sectional. The functional outcome measures of interest were daytime sleepiness (using the Epworth Sleepiness Scale, ESS), sleep-related symptoms (Pittsburgh Sleep Quality Index, PSQI), and sleep related quality of life (Functional Outcomes of Sleep Questionnaire, FOSQ). ANOVA and regression analyses examined the association between SDB severity (measured by indices of breathing disturbances and overnight oxygen saturation) and sleep time (by actigraphy) and these outcome measures. Regression models were adjusted for age, body mass index (BMI), and a medical comorbidity index. We specifically explored whether associations with indices of SDB were mediated by sleep deprivation by adjusting models for actigraphy-determined average total sleep time (TST) during the night. Community-based sample examined in home and outpatient settings. 461 surviving older women from the multicenter Study of Osteoporotic Fractures were examined during Visit 8 from 2002-03. All participants underwent in-home overnight polysomnography for one night and wrist actigraphy for a minimum of 3 24-h periods and completed the above functional outcomes questionnaires. N/A. Participants were aged 82.9 +/- 3.5 (mean +/- SD) years, had BMI of 27.9 +/- 5.1 kg/m2, and had an apnea-hypopnea index (AHI) of 15.7 +/- 15.1. AHI and TST demonstrated a weak correlation (r = -0.15). ESS score individually demonstrated a modest association with AHI, oxygen desaturation, and TST. The association of ESS score and AHI--but not oxygen desaturation-was attenuated to some extent by adjustment for TST. PSQI and FOSQ scores were not associated with measures of SDB severity or TST. After adjustment for TST, SDB severity in community-dwelling older women was not independently associated with self-reported daytime sleepiness, although there may be a modest association that is mediated through reduced TST. In older women, SDB severity was not associated with indices of sleep related symptoms or sleep related quality of life.
    Sleep 10/2007; 30(9):1181-8. · 5.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To examine the association between alcohol intake and problem drinking history and bone mineral density (BMD), falls and fracture risk. Cross-sectional and prospective cohort study. Six U.S. clinical centers. Five thousand nine hundred seventy-four men aged 65 and older. Alcohol intake and problem drinking histories were ascertained at baseline. Follow-up time was 1 year for falls and a mean of 3.65 years for fractures. Two thousand one hundred twenty-one participants (35.5%) reported limited alcohol intake (<12 drinks/y); 3,156 (52.8%) reported light intake (<14 drinks/wk), and 697 (11.7%) reported moderate to heavy intake (> or =14 drinks/wk) in the year before baseline. One thousand one men (16.8%) had ever had problem drinking. In multivariate models, as alcohol intake increased, so did hip and spine BMD (P for trend < .001). Greater alcohol intake was not associated with greater risk for nonspine or hip fractures. Men with light intake, but not moderate to heavy intake, had a lower risk of two or more incident falls (light intake: relative risk (RR) = 0.77, 95% confidence interval (CI) = 0.65-0.92; moderate to heavy intake: RR = 0.83, 95% CI = 0.63-1.10) than abstainers. Men with problem drinking had higher femoral neck (+1.3%) and spine BMD (+1.4%), and a higher risk of two or more falls (RR = 1.59; 95% CI = 1.30-1.94) than those without a history of problem drinking and similar total hip BMD and risk of fracture. In older men, recent alcohol intake is associated with higher BMD. Alcohol intake and fracture risk is unclear. Light alcohol intake may decrease the risk of falling, but a history of problem drinking increased fall risk.
    Journal of the American Geriatrics Society 12/2006; 54(11):1649-57. · 4.22 Impact Factor

Publication Stats

274 Citations
107.08 Total Impact Points

Institutions

  • 2008–2014
    • California Pacific Medical Center Research Institute
      • Research Institute
      San Francisco, California, United States
  • 2013
    • Oregon Health and Science University
      Portland, Oregon, United States
  • 2007–2012
    • University of California, San Francisco
      • • Division of Hospital Medicine
      • • Department of Psychiatry
      • • Department of Otolaryngology - Head and Neck Surgery
      San Francisco, CA, United States