Yurun Cai - Academia.edu (original) (raw)
Papers by Yurun Cai
Aging & Mental Health
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring
INTRODUCTIONSensory impairment (SI) is linked to cognitive decline, but its association with earl... more INTRODUCTIONSensory impairment (SI) is linked to cognitive decline, but its association with early cognitive impairment (ECI) is unclear.METHODSSensory functions (vision, hearing, vestibular function, proprioception, and olfaction) were measured between 2012 and 2018 in 414 Baltimore Longitudinal Study of Aging (BLSA) participants (age 74 ± 9 years; 55% women). ECI was defined as 1 standard deviation below age‐, sex‐, race‐, and education‐specific mean performance in Card Rotations or California Verbal Learning Test immediate recall. Log binomial models (cross‐sectional analysis) and Cox regression models (time‐to‐event analysis) were used to examine the association between SI and ECI.RESULTSCross‐sectionally, participants with ≥3 SI had twice the prevalence of ECI (prevalence ratio = 2.10, p = 0.02). Longitudinally, there was no significant association between SI and incident ECI over up to 6 years of follow‐up.DISCUSSIONSI is associated with higher prevalence, but not incident ECI...
The Journals of Gerontology: Series A
Background Understanding fall circumstances can help researchers better identify causes of falls ... more Background Understanding fall circumstances can help researchers better identify causes of falls and develop effective and tailored fall prevention programs. This study aims to describe fall circumstances among older adults from quantitative data using conventional statistical approaches and qualitative analyses using a machine learning approach. Methods The MOBILIZE Boston Study enrolled 765 community-dwelling adults aged 70 years and older in Boston, MA. Occurrence and circumstances of falls (ie, locations, activities, and self-reported causes of falls) were recorded using monthly fall calendar postcards and fall follow-up interviews with open- and close-ended questions during a 4-year period. Descriptive analyses were used to summarize circumstances of falls. Natural language processing was used to analyze narrative responses from open-ended questions. Results During the 4-year follow-up, 490 participants (64%) had at least 1 fall. Among 1 829 falls, 965 falls occurred indoors an...
Frontiers in Aging Neuroscience, Mar 28, 2023
ObjectiveDue to the long prodromal period for dementia pathology, approaches are needed to detect... more ObjectiveDue to the long prodromal period for dementia pathology, approaches are needed to detect cases before clinically recognizable symptoms are apparent, by which time it is likely too late to intervene. This study contrasted two theoretically-based algorithms for classifying early cognitive impairment (ECI) in adults aged ≥50 enrolled in the Baltimore Longitudinal Study of Aging.MethodTwo ECI algorithms were defined as poor performance (1 standard deviation [SD] below age-, sex-, race-, and education-specific means) in: (1) Card Rotations or California Verbal Learning Test (CVLT) immediate recall and (2) ≥1 (out of 2) memory or ≥3 (out of 6) non- memory tests. We evaluated concurrent criterion validity against consensus diagnoses of mild cognitive impairment (MCI) or dementia and global cognitive scores using receiver operating characteristic (ROC) curve analysis. Predictive criterion validity was evaluated using Cox proportional hazards models to examine the associations betwe...
Journal of the American Geriatrics Society
Innovation in Aging
Chronic pain is a risk factor contributing to mobility impairment and falls in older adults. Litt... more Chronic pain is a risk factor contributing to mobility impairment and falls in older adults. Little is known about the patterns of fall circumstances among older adults with pain. This prospective cohort study described frequencies of fall circumstances (i.e., location, activities, and self-reported causes of falls) and examined the relationship between chronic pain and fall circumstances among 765 community-dwelling older adults (mean age=78.1, 63.9% women) in the MOBILIZE Boston Study. Pain severity, fall occurrence, and fall circumstances were recorded using monthly calendar postcards and fall follow-up interviews during a 4-year follow-up. Descriptive analyses summarized frequencies of fall circumstances. Generalized estimating equation (GEE) models examined the relation between monthly pain ratings and circumstances of the first fall in the subsequent month. Among 1,829 falls, 965 (52.8%) falls occurred indoors and 804 (44.0%) falls occurred outdoors, 60 (3.2%) falls with missi...
Innovation in Aging
Revisiting the Teaching Nursing Home is a two-year pilot project to address the long-term care wo... more Revisiting the Teaching Nursing Home is a two-year pilot project to address the long-term care workforce shortage by introducing nursing students to geriatric nursing while improving quality of care within nursing homes. The initiative has multiple components: enhanced clinical rotations for nursing students with partner schools of nursing, implementation of the Institute for Healthcare Improvement Age-Friendly Health System “4M” quality improvement model, and an online learning network. Nursing students at three schools of nursing participated in the clinical rotations at regional nursing homes. The experience was limited to students in one specific course at each school of nursing. At the beginning and end of the spring 2022 semester, students rated their competence in: patient assessment, collaborating with the care team, gathering clinical information, medication review, eliciting resident values, and health promotion. Students also rated their preferences for working in long-te...
Innovation in Aging
Background Beat-to-beat blood pressure (BP) is an important cardiovascular output and regulated b... more Background Beat-to-beat blood pressure (BP) is an important cardiovascular output and regulated by neurophysiologic elements over multiple temporal scales. The multiscale dynamics of beat-to-beat BP fluctuation has thus been characterized using “BP complexity” and has been linked to age-related adverse health outcomes. We here aimed to examine the relationship of BP complexity to frailty, and if BP complexity mediates the association between arterial stiffness and frailty. Method: A total of 350 older adults completed assessments for frailty (i.e., Fried frailty phenotype criteria), arterial stiffness (i.e., average brachial-ankle pulse wave velocity), and beat-to-beat finger BP. The complexity of beat-to-beat systolic (SBP) and diastolic (DBP) BP series were measured using multiscale entropy. The relationships between frailty, BP complexity and arterial stiffness were examined using ANOVA and linear regression models. The effects of BP complexity on the association between arterial...
Medicine & Science in Sports & Exercise
Hypertension
Background: There is inconsistent evidence on the optimal time after standing to assess orthostat... more Background: There is inconsistent evidence on the optimal time after standing to assess orthostatic hypotension (OH). Objectives: To characterize the timing of OH after standing in older adults and the fall risk associated with OH at specific times. Methods: We performed a secondary analysis of the Study to Understand Fall Reduction and Vitamin D in You (STURDY). Blood pressure (BP) was measured in the supine position. Participants stood upright and underwent 6 standing BP measurements: 3 (M1-M3) immediately after standing, and 3 (M4-M6) after 3 minutes of standing. OH was defined as a decrease from supine systolic BP (SBP) of 20 or supine diastolic BP (DBP) of 10 mm Hg. We used generalized estimating equations to characterize changes in SBP, DBP, and OH over time. We used Cox models to examine the relationship between OH at each time point and subsequent falls. Results: There were 425 falls among 491 adults with 6,055 BP measurements and a median follow-up of 275 days. SBP/DBP decr...
Falls are a threat to the health of the older population and impair their functional independence... more Falls are a threat to the health of the older population and impair their functional independence in everyday life. Chronic pain is a risk factor contributing to mobility impairment and falls. This study aims to examine the association of chronic pain with 1) risk of injurious falls, and 2) circumstances of falls in community-dwelling older adults. This study used a prospective cohort study design and secondary data analysis. The MOBILIZE Boston Study (MBS) recruited 765 community-dwelling older adults aged 70 years and older in Boston area. Chronic pain characteristics including global pain severity, pain interference, and pain distribution were measured using Brief Pain Inventory (BPI) pain severity subscale, BPI pain interference subscale, and the joint pain questionnaire in the baseline home interview, respectively. Participants were followed up for up to 4.3 years for monthly pain ratings and fall data collection using monthly fall calendars, followed by a fall follow-up phone ...
Journal of the American Geriatrics Society
BACKGROUND Orthostatic hypotension (OH) based on a change from seated-to-standing blood pressure ... more BACKGROUND Orthostatic hypotension (OH) based on a change from seated-to-standing blood pressure (BP) is often used interchangeably with supine-to-standing BP. METHODS The Study to Understand Fall Reduction and Vitamin D in You (STURDY) was a randomized trial of vitamin D3 supplementation and fall in adults aged ≥70 years at high risk of falls. OH was defined as a drop in systolic or diastolic BP of at least 20 or 10 mmHg, measured at pre-randomization, 3-, 12-, and 24-month visits with each of 2 protocols: seated-to-standing and supine-to-standing. Participants were asked about orthostatic symptoms, and falls were ascertained via daily fall calendar, ad hoc reporting, and scheduled interviews. RESULTS Among 534 participants with 993 paired supine and seated assessments (mean age 76 ± 5 years, 42% women, 18% Black), mean baseline BP was 130 ± 19/68 ± 11 mmHg; 62% had a history of high BP or hypertension. Mean BP increased 3.5 (SE, 0.4)/2.6 (SE, 0.2) mmHg from sitting to standing, but decreased with supine to standing (mean change: -3.7 [SE, 0.5]/-0.8 [SE, 0.3] mmHg; P-value < 0.001). OH was detected in 2.1% (SE, 0.5) of seated versus 15.0% (SE, 1.4) of supine assessments (P < 0.001). While supine and seated OH were not associated with falls (HR: 1.55 [0.95, 2.52] vs 0.69 [0.30, 1.58]), supine systolic OH was associated with higher fall risk (HR: 1.77 [1.02, 3.05]). Supine OH was associated with self-reported fainting, blacking out, seeing spots and room spinning in the prior month (P-values < 0.03), while sitting OH was not associated with any symptoms (P-values ≥ 0.40). CONCLUSION Supine OH was more frequent, associated with orthostatic symptoms, and potentially more predictive of falls than seated OH.
BMC Geriatrics
Background Low serum 25-hydroxyvitamin D [25(OH)D] level is associated with a greater risk of fra... more Background Low serum 25-hydroxyvitamin D [25(OH)D] level is associated with a greater risk of frailty, but the effects of daily vitamin D supplementation on frailty are uncertain. This secondary analysis aimed to examine the effects of vitamin D supplementation on frailty using data from the Study To Understand Fall Reduction and Vitamin D in You (STURDY). Methods The STURDY trial, a two-stage Bayesian, response-adaptive, randomized controlled trial, enrolled 688 community-dwelling adults aged ≥ 70 years with a low serum 25(OH)D level (10–29 ng/mL) and elevated fall risk. Participants were initially randomized to 200 IU/d (control dose; n = 339) or a higher dose (1000 IU/d, 2000 IU/d, or 4000 IU/d; n = 349) of vitamin D3. Once the 1000 IU/d was selected as the best higher dose, other higher dose groups were reassigned to the 1000 IU/d group and new enrollees were randomized 1:1 to 1000 IU/d or control group. Data were collected at baseline, 3, 12, and 24 months. Frailty phenotype wa...
Frontiers in Cardiovascular Medicine, 2022
Background The blood pressure (BP) is regulated by multiple neurophysiologic elements over multip... more Background The blood pressure (BP) is regulated by multiple neurophysiologic elements over multiple temporal scales. The multiscale dynamics of continuous beat-to-beat BP series, which can be characterized by “BP complexity”, may, thus, capture the subtle changes of those elements, and be associated with the level of functional status in older adults. We aimed to characterize the relationships between BP complexity and several important functions in older adults and to understand the underlying factors contributing to BP complexity. Method A total of 400 older adults completed a series of clinical and functional assessments, a finger BP assessment of at least 10 min, and blood sample and vessel function tests. Their hypertensive characteristics, cognitive function, mobility, functional independence, blood composition, arterial stiffness, and endothelial function were assessed. The complexity of systolic (SBP) and diastolic (DBP) BP series was measured using multiscale entropy. Resul...
Innovation in Aging
Age-related sensory impairment, such as loss in vision or hearing, have been linked to poor brain... more Age-related sensory impairment, such as loss in vision or hearing, have been linked to poor brain health. Yet, the relationship between co-occurring sensory impairments and brain volumes remains unclear. We used cross-sectional sensory and brain imaging data from 208 cognitively normal participants of the Baltimore Longitudinal Study of Aging (mean age 72 years; 59% women). Sensory impairments were separately identified with vision, hearing, smell, proprioception, and vestibular function testing. Brain imaging volumes were derived using an automated multi-atlas approach. Multiple linear regression models were used to estimate brain volumetric differences by number of sensory impairments (0-5) or by multisensory impairment status (MSI; ≥2 impairments). For every one additional sensory impairment, there was lower volume in the orbitofrontal gyrus (beta=0.35 cc [SE=0.17], p=0.04) but higher volumes in the caudate (0.14 cc [0.05], p=0.006) and putamen (0.13 cc [0.06], p=0.043). Particip...
Artificial Intelligence in Medicine, 2022
Falls are a complex problem and play a leading role in the development of disabilities in the old... more Falls are a complex problem and play a leading role in the development of disabilities in the older population. While fall detection systems are important, it is also essential to work on fall preventive strategies, which will have the most significant impact in reducing disability in the elderly. In this work, we explore a prospective cohort study, specifically designed for examining novel risk factors for falls in community-living older adults. Various types of data were acquired that are common for real-world applications. Learning from multiple data sources often leads to more valuable findings than any of the data sources can provide alone. However, simply merging features from disparate datasets usually will not produce a synergy effect. Hence, it becomes crucial to properly manage the synergy, complementarity, and conflicts that arise in multi-source learning. In this work, we propose a multi-source learning approach called the Synergy LSTM model, which exploits complementarity among textual fall descriptions together with people's physical characteristics. We further use the learned complementarities to evaluate fall risk factors present in the data. Experiment results show that our Synergy LSTM model can significantly improve classification performance and capture meaningful relations between data from multiple sources.
Age and Ageing, 2021
Background Chronic pain is a risk factor contributing to mobility impairment and falls in older a... more Background Chronic pain is a risk factor contributing to mobility impairment and falls in older adults. Little is known about the patterns of circumstances of falls among older adults with chronicpain. Objective To examine the relationship between chronic pain and circumstances of falls including location, activities at the time of falls and self-reported causes of falls in older adults. Design Prospective cohort study. Setting Communities in/around Boston, Massachusetts. Subjects The MOBILIZE Boston Study enrolled 765 adults aged ≥70 years. Methods Pain severity, fall occurrence and fall circumstances were recorded using monthly calendar postcards and fall follow-up interviews during a 4-year follow-up period. Generalised estimating equation models were performed to examine the relation between monthly pain ratings and circumstances of the first fall in the subsequent month. Results Compared to fallers without chronic pain, fallers with moderate-to-severe pain had around twice the ...
Innovation in Aging, 2018
, education, and body mass index. This association was qualitatively consistent across gender and... more , education, and body mass index. This association was qualitatively consistent across gender and ethnicity subgroups (p for interactions > 0.05). Two autophagic genes, MCL1 (OR=1.23, p=0.007) and TSC22D3 (1.17, 0.032), but not CEBPD (1.03, 0.71), were associated with the comorbidity. This network was positively associated with type-2 diabetes (OR=1.23, p=0.023), chronic kidney disease (1.26, 0.037), hip fracture (2.14. 0.035), and hypertension (1.19, 0.002), marginally with cancer (1.19. 0.07), but not with cardiovascular disease (0.91, 0.32), chronic obstructive pulmonary disease (1.27, 0.23), and dementia (0.93, 0.78). In conclusion, our findings suggest that the autophagic flux transcriptional network reports aging mechanisms underlying multiple aging-related diseases.
Journal of Aging and Physical Activity
Wrist-worn accelerometry metrics are not well defined in older adults. Accelerometry data from 72... more Wrist-worn accelerometry metrics are not well defined in older adults. Accelerometry data from 720 participants (mean age 70 years, 55% women) were summarized into (a) total activity counts per day, (b) active minutes per day, (c) active bouts per day, and (d) activity fragmentation (the reciprocal of the mean active bout length). Linear regression and mixed-effects models were utilized to estimate associations between age and gait speed with wrist accelerometry. Activity counts per day, daily active minutes per day, and active bouts per day were negatively associated with age among all participants, while positive associations with activity fragmentation were only observed among those ≥65 years. More activity counts, more daily active minutes, and lower activity fragmentation were associated with faster gait speed. There were baseline age interactions with annual changes in total activity counts per day, active minutes per day, and activity fragmentation (Baseline age × Time, p <...
Aging & Mental Health
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring
INTRODUCTIONSensory impairment (SI) is linked to cognitive decline, but its association with earl... more INTRODUCTIONSensory impairment (SI) is linked to cognitive decline, but its association with early cognitive impairment (ECI) is unclear.METHODSSensory functions (vision, hearing, vestibular function, proprioception, and olfaction) were measured between 2012 and 2018 in 414 Baltimore Longitudinal Study of Aging (BLSA) participants (age 74 ± 9 years; 55% women). ECI was defined as 1 standard deviation below age‐, sex‐, race‐, and education‐specific mean performance in Card Rotations or California Verbal Learning Test immediate recall. Log binomial models (cross‐sectional analysis) and Cox regression models (time‐to‐event analysis) were used to examine the association between SI and ECI.RESULTSCross‐sectionally, participants with ≥3 SI had twice the prevalence of ECI (prevalence ratio = 2.10, p = 0.02). Longitudinally, there was no significant association between SI and incident ECI over up to 6 years of follow‐up.DISCUSSIONSI is associated with higher prevalence, but not incident ECI...
The Journals of Gerontology: Series A
Background Understanding fall circumstances can help researchers better identify causes of falls ... more Background Understanding fall circumstances can help researchers better identify causes of falls and develop effective and tailored fall prevention programs. This study aims to describe fall circumstances among older adults from quantitative data using conventional statistical approaches and qualitative analyses using a machine learning approach. Methods The MOBILIZE Boston Study enrolled 765 community-dwelling adults aged 70 years and older in Boston, MA. Occurrence and circumstances of falls (ie, locations, activities, and self-reported causes of falls) were recorded using monthly fall calendar postcards and fall follow-up interviews with open- and close-ended questions during a 4-year period. Descriptive analyses were used to summarize circumstances of falls. Natural language processing was used to analyze narrative responses from open-ended questions. Results During the 4-year follow-up, 490 participants (64%) had at least 1 fall. Among 1 829 falls, 965 falls occurred indoors an...
Frontiers in Aging Neuroscience, Mar 28, 2023
ObjectiveDue to the long prodromal period for dementia pathology, approaches are needed to detect... more ObjectiveDue to the long prodromal period for dementia pathology, approaches are needed to detect cases before clinically recognizable symptoms are apparent, by which time it is likely too late to intervene. This study contrasted two theoretically-based algorithms for classifying early cognitive impairment (ECI) in adults aged ≥50 enrolled in the Baltimore Longitudinal Study of Aging.MethodTwo ECI algorithms were defined as poor performance (1 standard deviation [SD] below age-, sex-, race-, and education-specific means) in: (1) Card Rotations or California Verbal Learning Test (CVLT) immediate recall and (2) ≥1 (out of 2) memory or ≥3 (out of 6) non- memory tests. We evaluated concurrent criterion validity against consensus diagnoses of mild cognitive impairment (MCI) or dementia and global cognitive scores using receiver operating characteristic (ROC) curve analysis. Predictive criterion validity was evaluated using Cox proportional hazards models to examine the associations betwe...
Journal of the American Geriatrics Society
Innovation in Aging
Chronic pain is a risk factor contributing to mobility impairment and falls in older adults. Litt... more Chronic pain is a risk factor contributing to mobility impairment and falls in older adults. Little is known about the patterns of fall circumstances among older adults with pain. This prospective cohort study described frequencies of fall circumstances (i.e., location, activities, and self-reported causes of falls) and examined the relationship between chronic pain and fall circumstances among 765 community-dwelling older adults (mean age=78.1, 63.9% women) in the MOBILIZE Boston Study. Pain severity, fall occurrence, and fall circumstances were recorded using monthly calendar postcards and fall follow-up interviews during a 4-year follow-up. Descriptive analyses summarized frequencies of fall circumstances. Generalized estimating equation (GEE) models examined the relation between monthly pain ratings and circumstances of the first fall in the subsequent month. Among 1,829 falls, 965 (52.8%) falls occurred indoors and 804 (44.0%) falls occurred outdoors, 60 (3.2%) falls with missi...
Innovation in Aging
Revisiting the Teaching Nursing Home is a two-year pilot project to address the long-term care wo... more Revisiting the Teaching Nursing Home is a two-year pilot project to address the long-term care workforce shortage by introducing nursing students to geriatric nursing while improving quality of care within nursing homes. The initiative has multiple components: enhanced clinical rotations for nursing students with partner schools of nursing, implementation of the Institute for Healthcare Improvement Age-Friendly Health System “4M” quality improvement model, and an online learning network. Nursing students at three schools of nursing participated in the clinical rotations at regional nursing homes. The experience was limited to students in one specific course at each school of nursing. At the beginning and end of the spring 2022 semester, students rated their competence in: patient assessment, collaborating with the care team, gathering clinical information, medication review, eliciting resident values, and health promotion. Students also rated their preferences for working in long-te...
Innovation in Aging
Background Beat-to-beat blood pressure (BP) is an important cardiovascular output and regulated b... more Background Beat-to-beat blood pressure (BP) is an important cardiovascular output and regulated by neurophysiologic elements over multiple temporal scales. The multiscale dynamics of beat-to-beat BP fluctuation has thus been characterized using “BP complexity” and has been linked to age-related adverse health outcomes. We here aimed to examine the relationship of BP complexity to frailty, and if BP complexity mediates the association between arterial stiffness and frailty. Method: A total of 350 older adults completed assessments for frailty (i.e., Fried frailty phenotype criteria), arterial stiffness (i.e., average brachial-ankle pulse wave velocity), and beat-to-beat finger BP. The complexity of beat-to-beat systolic (SBP) and diastolic (DBP) BP series were measured using multiscale entropy. The relationships between frailty, BP complexity and arterial stiffness were examined using ANOVA and linear regression models. The effects of BP complexity on the association between arterial...
Medicine & Science in Sports & Exercise
Hypertension
Background: There is inconsistent evidence on the optimal time after standing to assess orthostat... more Background: There is inconsistent evidence on the optimal time after standing to assess orthostatic hypotension (OH). Objectives: To characterize the timing of OH after standing in older adults and the fall risk associated with OH at specific times. Methods: We performed a secondary analysis of the Study to Understand Fall Reduction and Vitamin D in You (STURDY). Blood pressure (BP) was measured in the supine position. Participants stood upright and underwent 6 standing BP measurements: 3 (M1-M3) immediately after standing, and 3 (M4-M6) after 3 minutes of standing. OH was defined as a decrease from supine systolic BP (SBP) of 20 or supine diastolic BP (DBP) of 10 mm Hg. We used generalized estimating equations to characterize changes in SBP, DBP, and OH over time. We used Cox models to examine the relationship between OH at each time point and subsequent falls. Results: There were 425 falls among 491 adults with 6,055 BP measurements and a median follow-up of 275 days. SBP/DBP decr...
Falls are a threat to the health of the older population and impair their functional independence... more Falls are a threat to the health of the older population and impair their functional independence in everyday life. Chronic pain is a risk factor contributing to mobility impairment and falls. This study aims to examine the association of chronic pain with 1) risk of injurious falls, and 2) circumstances of falls in community-dwelling older adults. This study used a prospective cohort study design and secondary data analysis. The MOBILIZE Boston Study (MBS) recruited 765 community-dwelling older adults aged 70 years and older in Boston area. Chronic pain characteristics including global pain severity, pain interference, and pain distribution were measured using Brief Pain Inventory (BPI) pain severity subscale, BPI pain interference subscale, and the joint pain questionnaire in the baseline home interview, respectively. Participants were followed up for up to 4.3 years for monthly pain ratings and fall data collection using monthly fall calendars, followed by a fall follow-up phone ...
Journal of the American Geriatrics Society
BACKGROUND Orthostatic hypotension (OH) based on a change from seated-to-standing blood pressure ... more BACKGROUND Orthostatic hypotension (OH) based on a change from seated-to-standing blood pressure (BP) is often used interchangeably with supine-to-standing BP. METHODS The Study to Understand Fall Reduction and Vitamin D in You (STURDY) was a randomized trial of vitamin D3 supplementation and fall in adults aged ≥70 years at high risk of falls. OH was defined as a drop in systolic or diastolic BP of at least 20 or 10 mmHg, measured at pre-randomization, 3-, 12-, and 24-month visits with each of 2 protocols: seated-to-standing and supine-to-standing. Participants were asked about orthostatic symptoms, and falls were ascertained via daily fall calendar, ad hoc reporting, and scheduled interviews. RESULTS Among 534 participants with 993 paired supine and seated assessments (mean age 76 ± 5 years, 42% women, 18% Black), mean baseline BP was 130 ± 19/68 ± 11 mmHg; 62% had a history of high BP or hypertension. Mean BP increased 3.5 (SE, 0.4)/2.6 (SE, 0.2) mmHg from sitting to standing, but decreased with supine to standing (mean change: -3.7 [SE, 0.5]/-0.8 [SE, 0.3] mmHg; P-value < 0.001). OH was detected in 2.1% (SE, 0.5) of seated versus 15.0% (SE, 1.4) of supine assessments (P < 0.001). While supine and seated OH were not associated with falls (HR: 1.55 [0.95, 2.52] vs 0.69 [0.30, 1.58]), supine systolic OH was associated with higher fall risk (HR: 1.77 [1.02, 3.05]). Supine OH was associated with self-reported fainting, blacking out, seeing spots and room spinning in the prior month (P-values < 0.03), while sitting OH was not associated with any symptoms (P-values ≥ 0.40). CONCLUSION Supine OH was more frequent, associated with orthostatic symptoms, and potentially more predictive of falls than seated OH.
BMC Geriatrics
Background Low serum 25-hydroxyvitamin D [25(OH)D] level is associated with a greater risk of fra... more Background Low serum 25-hydroxyvitamin D [25(OH)D] level is associated with a greater risk of frailty, but the effects of daily vitamin D supplementation on frailty are uncertain. This secondary analysis aimed to examine the effects of vitamin D supplementation on frailty using data from the Study To Understand Fall Reduction and Vitamin D in You (STURDY). Methods The STURDY trial, a two-stage Bayesian, response-adaptive, randomized controlled trial, enrolled 688 community-dwelling adults aged ≥ 70 years with a low serum 25(OH)D level (10–29 ng/mL) and elevated fall risk. Participants were initially randomized to 200 IU/d (control dose; n = 339) or a higher dose (1000 IU/d, 2000 IU/d, or 4000 IU/d; n = 349) of vitamin D3. Once the 1000 IU/d was selected as the best higher dose, other higher dose groups were reassigned to the 1000 IU/d group and new enrollees were randomized 1:1 to 1000 IU/d or control group. Data were collected at baseline, 3, 12, and 24 months. Frailty phenotype wa...
Frontiers in Cardiovascular Medicine, 2022
Background The blood pressure (BP) is regulated by multiple neurophysiologic elements over multip... more Background The blood pressure (BP) is regulated by multiple neurophysiologic elements over multiple temporal scales. The multiscale dynamics of continuous beat-to-beat BP series, which can be characterized by “BP complexity”, may, thus, capture the subtle changes of those elements, and be associated with the level of functional status in older adults. We aimed to characterize the relationships between BP complexity and several important functions in older adults and to understand the underlying factors contributing to BP complexity. Method A total of 400 older adults completed a series of clinical and functional assessments, a finger BP assessment of at least 10 min, and blood sample and vessel function tests. Their hypertensive characteristics, cognitive function, mobility, functional independence, blood composition, arterial stiffness, and endothelial function were assessed. The complexity of systolic (SBP) and diastolic (DBP) BP series was measured using multiscale entropy. Resul...
Innovation in Aging
Age-related sensory impairment, such as loss in vision or hearing, have been linked to poor brain... more Age-related sensory impairment, such as loss in vision or hearing, have been linked to poor brain health. Yet, the relationship between co-occurring sensory impairments and brain volumes remains unclear. We used cross-sectional sensory and brain imaging data from 208 cognitively normal participants of the Baltimore Longitudinal Study of Aging (mean age 72 years; 59% women). Sensory impairments were separately identified with vision, hearing, smell, proprioception, and vestibular function testing. Brain imaging volumes were derived using an automated multi-atlas approach. Multiple linear regression models were used to estimate brain volumetric differences by number of sensory impairments (0-5) or by multisensory impairment status (MSI; ≥2 impairments). For every one additional sensory impairment, there was lower volume in the orbitofrontal gyrus (beta=0.35 cc [SE=0.17], p=0.04) but higher volumes in the caudate (0.14 cc [0.05], p=0.006) and putamen (0.13 cc [0.06], p=0.043). Particip...
Artificial Intelligence in Medicine, 2022
Falls are a complex problem and play a leading role in the development of disabilities in the old... more Falls are a complex problem and play a leading role in the development of disabilities in the older population. While fall detection systems are important, it is also essential to work on fall preventive strategies, which will have the most significant impact in reducing disability in the elderly. In this work, we explore a prospective cohort study, specifically designed for examining novel risk factors for falls in community-living older adults. Various types of data were acquired that are common for real-world applications. Learning from multiple data sources often leads to more valuable findings than any of the data sources can provide alone. However, simply merging features from disparate datasets usually will not produce a synergy effect. Hence, it becomes crucial to properly manage the synergy, complementarity, and conflicts that arise in multi-source learning. In this work, we propose a multi-source learning approach called the Synergy LSTM model, which exploits complementarity among textual fall descriptions together with people's physical characteristics. We further use the learned complementarities to evaluate fall risk factors present in the data. Experiment results show that our Synergy LSTM model can significantly improve classification performance and capture meaningful relations between data from multiple sources.
Age and Ageing, 2021
Background Chronic pain is a risk factor contributing to mobility impairment and falls in older a... more Background Chronic pain is a risk factor contributing to mobility impairment and falls in older adults. Little is known about the patterns of circumstances of falls among older adults with chronicpain. Objective To examine the relationship between chronic pain and circumstances of falls including location, activities at the time of falls and self-reported causes of falls in older adults. Design Prospective cohort study. Setting Communities in/around Boston, Massachusetts. Subjects The MOBILIZE Boston Study enrolled 765 adults aged ≥70 years. Methods Pain severity, fall occurrence and fall circumstances were recorded using monthly calendar postcards and fall follow-up interviews during a 4-year follow-up period. Generalised estimating equation models were performed to examine the relation between monthly pain ratings and circumstances of the first fall in the subsequent month. Results Compared to fallers without chronic pain, fallers with moderate-to-severe pain had around twice the ...
Innovation in Aging, 2018
, education, and body mass index. This association was qualitatively consistent across gender and... more , education, and body mass index. This association was qualitatively consistent across gender and ethnicity subgroups (p for interactions > 0.05). Two autophagic genes, MCL1 (OR=1.23, p=0.007) and TSC22D3 (1.17, 0.032), but not CEBPD (1.03, 0.71), were associated with the comorbidity. This network was positively associated with type-2 diabetes (OR=1.23, p=0.023), chronic kidney disease (1.26, 0.037), hip fracture (2.14. 0.035), and hypertension (1.19, 0.002), marginally with cancer (1.19. 0.07), but not with cardiovascular disease (0.91, 0.32), chronic obstructive pulmonary disease (1.27, 0.23), and dementia (0.93, 0.78). In conclusion, our findings suggest that the autophagic flux transcriptional network reports aging mechanisms underlying multiple aging-related diseases.
Journal of Aging and Physical Activity
Wrist-worn accelerometry metrics are not well defined in older adults. Accelerometry data from 72... more Wrist-worn accelerometry metrics are not well defined in older adults. Accelerometry data from 720 participants (mean age 70 years, 55% women) were summarized into (a) total activity counts per day, (b) active minutes per day, (c) active bouts per day, and (d) activity fragmentation (the reciprocal of the mean active bout length). Linear regression and mixed-effects models were utilized to estimate associations between age and gait speed with wrist accelerometry. Activity counts per day, daily active minutes per day, and active bouts per day were negatively associated with age among all participants, while positive associations with activity fragmentation were only observed among those ≥65 years. More activity counts, more daily active minutes, and lower activity fragmentation were associated with faster gait speed. There were baseline age interactions with annual changes in total activity counts per day, active minutes per day, and activity fragmentation (Baseline age × Time, p <...