Objective Measures Of Activity Research Articles

Relationship between Patient-reported Outcome Measures and Accelerometer-measured Physical Activity and Sleep in Patients with Post-herpetic Neuralgia.

Available treatment for chronic neuropathic pain is still limited, and the effect is modest. Thus, clinicians aim to improve activity and quality of life despite pain. The objective monitoring of activity is attracting attention in chronic pain assessments. Therefore, we objectively evaluated daytime activity and sleep in patients with post-herpetic neuralgia, using actigraphy to determine risk factors for decreased activity. Patients with post-herpetic neuralgia wore an actigraph (a wristwatch-like accelerometer) on the non-dominant hand. The actigraph measured day-time activity and sleep, which were compared with patient-reported subjective pain and sleep assessments. Fifty-four patients with post-herpetic neuralgia who visited our outpatient clinic completed questionnaires and a week of actigraph monitoring. Subjective scores of pain intensity, neuropathic pain, disability in daily life, pain-catastrophizing thoughts, and insomnia were all well correlated. However, the actigraph-monitored activity levels, using two equations, and sleep quality were not associated with any pain- or sleep-related subjective scores. The discrepancy between the subjective and objective scores in this study may be due to 1) features of post-herpetic neuralgia, an archetype of peripheral neuropathic pain affecting no motor nerves, 2) actigraph measurement limitations regarding the sedentary life of the elderly, or 3) activity misperception, a new proposition explaining the discrepancy between subjective and objective measures of activity, similar to the sleep state misperception. In patients with post-herpetic neuralgia, high pain intensity may be reported in those with highly maintained activity, in which treatment must be selected cautiously to prevent interruption of their physical abilities.

Abstract 3560: Quantified kinematics and wearable sensors to predict serious adverse events in patients undergoing cancer therapy trials

Abstract Background: Serious adverse events (SAEs) are a critical determinant of drug toxicity in clinical trials. However the drivers of toxicity may be related to patient factors as much or more than drug related factors. Prior studies have shown that time in non-sedentary activity predicted toxicity in cancer patients receiving highly emetogenic chemotherapy. SAEs are a critical determinant of drug toxicity in clinical trials. However, predicting SAEs using conventional PS scales measurements, such as ECOG is challenging because measurements can vary among observers. Prior studies have used activity trackers to measure physical activity and showed that time spent in non-sedentary activity predicted toxicity in cancer patients receiving highly emetogenic chemotherapy. Here, we sought to extend these findings to early phase clinical trial participants by examining data collected in two single-arm, observational, prospective studies at USC Keck and MD Anderson centers. We explored the use of out-of-clinic wearable sensors as an objective metric of frailty so as to identify patients at risk for therapy complications. Methods: Adult patients diagnosed with cancer and enrolled in early stage clinical trials across USC Keck and MD Anderson centers were included in parallel single-arm, observational, prospective studies. Patients used a consumer grade wearable activity tracker (Fitbit) and the study examined associations between the number of severe adverse events to activity levels measured by metabolic equivalents (METs) and get-up-go times across the first 30 days. Trends were assessed using t-tests. Results: 36 eligible patients were included in METs activity analysis. There was a total of 16 recorded incidences of SAEs within the first 30 study days, with 10 patients experiencing at least one SAE. The median non-sedentary time for patients with no SAEs was 27.5 hours above 1.5 METs per week, compared to 21.5 hours for those with at least one SAE occurrence (p-value=0.0146, r2=0.1629). The median get-up-go times for those without SAEs was 10.0 seconds (n=26) and with SAEs was 9.8 seconds (n=10), (p-value=0.828, r2=0.0014). Conclusions: Non-sedentary time, as an objective measure of activity, can be used to identify those patients who are at greatest risk for SAEs in clinical trials. Widely available and inexpensive consumer grade sensors can be used as a stratification tool. Findings should be confirmed in larger patient cohorts across a wider variety of trial settings. Figure 1: Weekly non-sedentary hours vs. presence of SAE in first 30 days of trial enrollment Citation Format: Eli Tran, Luciano Nocera, Anand Kolatkar, Anthony El-Khoueiry, Jacob Thomas, Peter Kuhn, Andrew Zeng, Megumi Kai, Meghan Karuturi, Jorge Nieva. Quantified kinematics and wearable sensors to predict serious adverse events in patients undergoing cancer therapy trials [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3560.

Comparison of Self-Reported vs Objective Measures of Long-Term Community Ambulation in Lower Limb Prosthesis Users

ObjectiveTo determine normal variation in walking metrics in a population of lower limb amputees who use lower limb prostheses over a 6-month period and to provide a means to interpret clinically meaningful change in those community walking metrics. DesignProspective cohort study monitoring walking behavior and subjective and objective measures of activity. SettingVeterans Administration and university amputee clinics. Participants86 individuals with lower limb amputation who use protheses. InterventionsStepWatch activity monitor tracked subjects’ walking for 24 weeks; Global Mobility Change Rating collected weekly. Main Outcome MeasuresAssociation between change in Global Mobility Change Rating and change in any of the walking metrics. ResultsWalking metrics including step count, cadence, cadence variability, and walking distance in a population of lower limb prosthesis users were obtained. There was a high correlation in the walking metrics indicating higher function with higher functional classification level (K-levels) but also substantial overlap in all metrics and a very weak correlation between subject-reported activity level and objective measures of walking performance. ConclusionThe overlap in walking metrics with all K-levels demonstrates that no single metric measured by StepWatch can determine K-level with 100% accuracy. As previously demonstrated in other populations, subjects’ interpretations of their general activity level was inaccurate, regardless of their age or activity level. Objective measures of walking appear to provide a more accurate representation of patients’ activity levels in the community than self-report. Therefore, objective measures of walking are useful in supporting K-level determinations. However, clinicians cannot rely on a single metric to determine K-level.

Subjective and Objective Measures of Activity in Depressed and Non-depressed Individuals in Everyday Life

Reduced physical activity is considered a key feature of major depressive disorder (MDD). However, research directly comparing non-depressed controls and patients yielded mixed findings. In contrast to most previous research, this study compared objective as well as subjective activity levels of individuals with MDD with non-depressed controls and used an ambulatory assessment method. Moreover, we investigated whether objective and subjective measures of activity could predict mood. On two consecutive days, physical activity of 35 MDD patients and 36 non-depressed control participants were assessed objectively using an accelerometer and subjectively with hourly ecological momentary assessments. During the same assessment, participants mood was monitored. No significant differences between MDD patients and control participants in objective and most of the subjective activity measures were observed. We found significant associations between objective and subjective measures of activity in non-depressed as well as in MDD patients. Objective but not subjective measures of activity predicted subsequent mood. Our results support the notion that the association between MDD and activity level is complex and depends on moderating factors.

Functional recovery after discharge in enhanced recovery video-assisted thoracoscopic lobectomy: a pilot prospective cohort study.

Little is known about functional recovery following patient discharge in an established enhanced recovery programme after video-assisted thoracoscopic lobectomy. We conducted a single-centre pilot prospective observational cohort study. We hypothesised that patients achieved early functional recovery after discharge. A total of 32 patients aged ≥ 18 years were enrolled. A digital device was used for objective activity measurements, and patient-reported outcomes were collected as subjective measurements. Primary outcomes were the difference in physical activity; sleep duration; pain; fatigue; and average quality of life scores between pre-operative baseline and 7 days following discharge. The secondary outcome was the reason for reduced daily activity during the first 7 days after discharge. Median (IQR [range]) length of stay was 3 (2-5 [1-13]) days. Up to post-discharge day 7, total, lower intensity and moderate-to-vigorous activities were lower than pre-operative activity (p < 0.001; p = 0.005 and p = 0.027, respectively). Numerical rating scale (0-10) pain scores increased postoperatively at rest (mean difference 1.2, p < 0.001) and during walking (mean difference 1.4, p < 0.001). Fatigue assessed by the Christensen Fatigue Scale (1-10) was also increased postoperatively (mean difference 1.7, p = 0.001). There was a reduction in quality of life scores, while sedentary activity and sleep duration were unchanged postoperatively. Dominant reasons for not recovering daily activity included fatigue in 43% and pain in 33% of patients. Despite compliance with an enhanced recovery programme with a median length of hospital stay of 3 days after video-assisted thoracoscopic lobectomy, functional recovery was not achieved within 7 days after hospital discharge. Reduction in postoperative pain and fatigue are important factors to enhance functional recovery.

The validity of the International Physical Activity Questionnaire (IPAQ) for adults with progressive muscle diseases

Purpose Measuring the physical activity of adults with progressive muscle diseases is important to inform clinical practice, for activity recommendations and for outcomes meaningful to participants in clinical trials. Despite its wide use, the measurement properties of the International Physical Activity Questionnaire (IPAQ) have not been established in a muscle disease population. Materials and methods The sample of 103 adults with progressive muscle diseases included independently mobile participants and wheelchair users. Their home-based activity measured by the IPAQ was compared to simultaneous weeks of accelerometer activity data collected remotely in a longitudinal, measure evaluation study. Validity, reliability, and responsiveness were evaluated for the IPAQ alone, and for the IPAQ used in conjunction with a smart activity monitor. Results The IPAQ did not demonstrate satisfactory criterion validity, reliability or responsiveness and it systematically overestimated moderate and vigorous physical activity time by 161 minutes per week. Measurement properties of the IPAQ were improved when it was used in combination with a smart activity monitor. Conclusions The IPAQ did not have satisfactory measurement properties compared to accelerometry in adults with progressive muscle disease. Combining self-report and objective activity measures might improve the accuracy of physical activity assessment in this and other comparable populations. Implications for Rehabilitation Physical activity is a meaningful health outcome for adults with progressive muscle diseases, for whom precise activity quantification is important because of the potential for activity-related disease exacerbation. The International Physical Activity Questionnaire (IPAQ) had unsatisfactory measurement properties compared to accelerometry; however, these were improved by adjunctive smart activity monitoring. Objective or combined physical activity measurement is recommended over self-report alone for clinical assessment of physical activity as part of rehabilitation and self-management programmes.

Lower average daily step count is associated with poorer executive function and rurality in a veteran cohort

AbstractBackgroundAn active lifestyle is associated with better cognitive health in older individuals. This relationship is understudied in U.S. Veterans, a population at risk of cognitive impairment due to the high prevalence of associated risk factors and comorbidities. Passive monitoring of daily activities provides objective measures of activity that may serve as a sensitive index of day‐to‐day function and dementia risk.MethodParticipants (age &gt; 57) were enrolled as part of Collaborative Aging Research using Technology (CART), a multi‐site study examining the feasibility of unobtrusive remote sensing and monitoring of physical, cognitive, and health‐related activities. The Veteran cohort consists of volunteers living in largely rural communities in the Pacific Northwest, self‐identified as being a Veteran, and included their cohabitant, if applicable. Daily step counts were acquired using a wrist‐worn device. Baseline one‐month averages were compared with rurality and cognitive function.Result114 nondemented participants residing in 67 homes underwent neuropsychological assessment and passive monitoring of daily activities (55% male, age 70.7, MOCA 23.4). 70% resided in a rural area (rural‐urban commuting area (RUCA) score &gt; 4 ) and 29% had &gt; three vascular risk factors. Participants with 14+ days of gait activity measured within a one‐month period near baseline cognitive assessments not using a walker in the home were included (n = 107). Average daily step count obtained over an average of 27.7 days was 3,065 (median 2,515) and was greater in large rural towns compared with small‐isolated rural (p = 0.07) or urban (p = 0.04) towns. After adjusting for potential confounders, lower average daily steps were associated with worse performance in executive function, a relationship observed in Veterans in large rural, but not urban or small rural towns.ConclusionIn a cohort comprised primarily of rural Veteran’s and their spouses, lower average number of steps per day is associated with poorer executive function and this relationship varied by rurality. Real‐world monitoring of daily activities may identify those at greatest risk of cognitive decline for interventional studies aimed at dementia prevention in older individuals, and is of particular relevance in rural settings, where access to specialty care is limited.

The Impact of Physical Activity on the Prevention of Type 2 Diabetes: Evidence and Lessons Learned From the Diabetes Prevention Program, a Long-Standing Clinical Trial Incorporating Subjective and Objective Activity Measures.

Across the Diabetes Prevention Program (DPP) follow-up, cumulative diabetes incidence remained lower in the lifestyle compared with the placebo and metformin randomized groups and could not be explained by weight. Collection of self-reported physical activity (PA) (yearly) with cross-sectional objective PA (in follow-up) allowed for examination of PA and its long-term impact on diabetes prevention. Yearly self-reported PA and diabetes assessment and oral glucose tolerance test results (fasting glucose semiannually) were collected for 3,232 participants with one accelerometry assessment 11-13 years after randomization (n = 1,793). Mixed models determined PA differences across treatment groups. The association between PA and diabetes incidence was examined using Cox proportional hazards models. There was a 6% decrease (Cox proportional hazard ratio 0.94 [95% CI 0.92, 0.96]; P < 0.001) in diabetes incidence per 6 MET-h/week increase in time-dependent PA for the entire cohort over an average of 12 years (controlled for age, sex, baseline PA, and weight). The effect of PA was greater (12% decrease) among participants less active at baseline (<7.5 MET-h/week) (n = 1,338) (0.88 [0.83, 0.93]; P < 0.0001), with stronger findings for lifestyle participants. Lifestyle had higher cumulative PA compared with metformin or placebo (P < 0.0001) and higher accelerometry total minutes per day measured during follow-up (P = 0.001 and 0.047). All associations remained significant with the addition of weight in the models. PA was inversely related to incident diabetes in the entire cohort across the study, with cross-sectional accelerometry results supporting these findings. This highlights the importance of PA within lifestyle intervention efforts designed to prevent diabetes and urges health care providers to consider both PA and weight when counseling high-risk patients.

Prospective, longitudinal digital activity monitoring before and after treatment of low-risk oropharyngeal squamous cell carcinoma: A feasibility study.

6578 Background: Given the expected excellent prognosis of low-risk oropharyngeal squamous cell carcinoma (OPSCC), consideration of long-term toxicity and functional outcomes has become increasingly important. Activity monitors (e.g. FITBIT) are imperfect but have been shown to have reasonable validity in healthy adults. Here we aimed to test the feasibility of using medical grade longitudinal digital activity monitoring to better define objective functional outcomes after treatment of low-risk OPSCC. Methods: This prospective, observational parallel cohort study included patients with previously untreated stage I-III (AJCC 7) OPSCC eligible for standard of care single-modality treatment with either Intensity-Modulated Proton Therapy (IMPT) or TransOral Robotic Surgery (TORS). Objective Actigraph accelerometer data (Actigraph, Pensacola, FL) were collected continuously for 1 week at baseline, 3, 6 and 12 months after treatment along with subjective patient-reported outcome (PRO) measures. Results: Forty-four patients (34M, 10F) enrolled with median age 59 years (range: 42-78). Baseline, 3 and 6 month activity data were available for 40 patients (91%): 16 IMPT and 24 TORS. There was a significant decrease in mean percent of day performing moderate to vigorous physical activity (MVPA) (-0.78, 0.021) mean number of steps/minute (-1.1, p = 0.035), and mean kcals/day (-115.9, p &lt; 0.001) from baseline to 3 months after treatment for the overall cohort. A significant decrease in mean kcals/day (-82.2, p = 0.004) persisted for the overall cohort at 6 months with no significant difference between groups. Conclusions: Longitudinal digital activity monitoring is feasible before and after treatment of low-risk OPSCC. This approach may offer objective functional endpoints for future de-escalation trials. Similar short-term decreases in objective activity measurements were observed after IMPT and TORS. Long-term (12 month) activity data and correlations to subjective PRO measures will be available at the time of presentation. Clinical trial information: 02663583 .

Psychometric properties of the questionnaire data on individual history of activity : Validity and reliability of the lifetime leisure physical activity questionnaire in community-dwelling older adults

The lifetime leisure physical activity questionnaire (LLPAQ) is aderivative of the historical leisure activity questionnaire (HLAQ) of Kriska etal. (1988) for capture of the complete activity biography. The present study investigated the reliability and the validity of the LLPAQ of Engeroff and Vogt (2018). Atotal of 47seniors (75-90years old) participated in an objective measurement of activity and completed the LLPAQ. For validation of the questionnaire accelerometer-based data were compared with the subjective report in the LLPAQ on physical activity from the last year of life using a correlation analysis. Data from asecond LLPAQ filled out by 14participants (after 6weeks) were used for reliability analysis (difference and correlation). Subjectively captured data on the physical activity of the last year correlated with the objectively measured activity data (r = 0.311, p = 0.033). Although self-reporting overestimated the amount by almost 176%, test-retest data on MET-hours per episode showed a correlation (r = 0.824; p < 0.001). Check for internal consistency of individual episodes across the lifespan yielded aCronbach's alpha of 0.8 (p < 0.001). The LLPAQ showed good reliability values in the retest at 6weeks, particularly considering the problem of manifold errors of subjective activity measurement in participants at old age. Regarding the discrepancy between the time periods of objective (1week) and subjective (1year) surveys, the proven medium effect strength indicates the high validity of the questionnaire.

PAIN, AFFECT, AND OBJECTIVE ACTIVITY LEVELS IN OLDER ADULTS WITH OSTEOARTHRITIS

This research examined the relation between physical activity, pain, and mood among older adults with osteoarthritis (OA). Physical activity is associated with long-term maintenance of function in persons with chronic pain (Dunlop et al., 2014), but less is known about the association between objective measures of activity and transient mood states. Therefore, we captured the activity and mood levels of 218 older adults with knee OA over a seven-day period. Wrist and waist accelerometers captured small and large motor movements. Self-reported momentary pain and affect were collected through phone calls four times daily. We examined average and peak activity levels over the 4-hour windows between self-reports. Cross-sectionally, there was no association between momentary pain and activity. Average large motor movement was positively associated with positive affect and negatively associated with negative affect. Analyses revealed one association between affect and average previous activity; small motor movements predicted greater positive affect. Peak levels of both movements predicted greater positive affect, but only peak wrist activity predicted negative affect. Peak small motor movement at the previous call was associated with both positive and negative affect. These results provide insight into the unique contributions of small and large motor activity to mood and pain states. It appears that average large motor movements and prior small motor activity may have the greatest impact on momentary affect. Further study of distinct activity types and mood will be important for understanding and improving the quality of life among individuals diagnosed with OA (Supported by R01-AG041655).

How much do hospitalized adults move? A systematic review and meta-analysis

AimTo quantify the type and duration of physical activity performed by hospitalized adults. BackgroundInactivity is pervasive among hospitalized patients and is associated with increased mortality, functional decline, and cognitive impairment. Objective measurement of activity is necessary to examine associations with clinical outcomes and quantify optimal inpatient mobility interventions. MethodsWe used PRISMA guidelines to search three databases in December 2017 to retrieve original research evaluating activity type and duration among adult acute-care inpatients. We abstracted data on inpatient population, measurement method, monitoring time, activity duration, and study quality. ResultsThirty-eight articles were included in the review and 7 articles were included in the meta-analysis. Study populations included geriatric (n = 5), surgical (n = 5), medical (n = 12), post-stroke (n = 10), psychiatric (n = 2), and critical care inpatients (n = 4). To measure activity, 29% of studies used human observation and 71% used activity monitors. Among inpatient populations, 87–100% of time was spent sitting or lying in-bed. Among medical inpatients monitored over a continuous 24-hour period (n = 7), 70 min per day was spent standing/walking (95% CI 57–83 min). ConclusionsThis review provides a baseline assessment and benchmark of inpatient activity, which can be used to compare inpatient mobility practices. While there is substantial heterogeneity in how researchers measure and define how much inpatients move, there is consistent evidence that patients are mostly inactive and in-bed during hospitalization. Future research is needed to establish standardized methods to accurately and consistently measure inpatient mobility over time.

Physical activity and sedentary activity: population epidemiology and concordance in Australian children aged 11-12 years and their parents.

ObjectivesTo describe the epidemiology and parent–child concordance of objectively measured physical activity in a population-based sample of Australian parent–child dyads.DesignCross-sectional study (Child Health CheckPoint) nested within the Longitudinal Study of Australian Children.SettingAssessment centres in seven Australian cities and eight regional towns or home visits; February 2015–March 2016.ParticipantsOf all CheckPoint families (n=1874), 1261 children (50% girls) and 1358 parent (88% mothers) provided objectively measured activity data, comprising 1077 parent–child dyads.Outcome measuresActivity behaviour was assessed by GENEActiv accelerometer. Duration of moderate-to-vigorous physical activity (MVPA) and vigorous physical activity and sedentary behaviour (SB) were derived using Cobra custom software, along with MVPA/SB fragmentation and mean daily activity. Pearson’s correlation coefficients and linear regression estimated parent–child concordance. Survey weights and methods accounted for the complex sample design and clustering.ResultsAlthough parents had average lower accelerometry counts than children (mean [SD] 209 [46] vs 284 [71] g.min), 93% of parents met MVPA daily duration guidelines on published cutpoints (mean [SD] 125 [63] min/day MVPA), compared with only 15% of children (mean 32 [27] min). Parents showed less daily SB duration (parents: 540 [101], children: 681 [69] minutes) and less fragmented accumulation of MVPA (parents: α=1.85, children: α=2.00). Parent–child correlation coefficients were 0.16 (95% CI 0.11 to 0.22) for MVPA duration, 0.10 (95% CI 0.04 to 0.16) for MVPA fragmentation, 0.16 (95% CI 0.11 to 0.22) for SB duration and 0.18 (95% CI 0.12 to 0.23) for SB fragmentation.ConclusionsStandardised cutpoints are needed for objective activity measures to inform activity guidelines across the lifecourse. This may reflect large amounts of time in non-shared environments (school and work).

Quantified Activity Measurement for Medical Use in Movement Disorders through IR-UWB Radar Sensor.

Movement disorders, such as Parkinson’s disease, dystonia, tic disorder, and attention-deficit/hyperactivity disorder (ADHD) are clinical syndromes with either an excess of movement or a paucity of voluntary and involuntary movements. As the assessment of most movement disorders depends on subjective rating scales and clinical observations, the objective quantification of activity remains a challenging area. The purpose of our study was to verify whether an impulse radio ultra-wideband (IR-UWB) radar sensor technique is useful for an objective measurement of activity. Thus, we proposed an activity measurement algorithm and quantitative activity indicators for clinical assistance, based on IR-UWB radar sensors. The received signals of the sensor are sufficiently sensitive to measure heart rate, and multiple sensors can be used together to track the positions of people. To measure activity using these two features, we divided movement into two categories. For verification, we divided these into several scenarios, depending on the amount of activity, and compared with an actigraphy sensor to confirm the clinical feasibility of the proposed indicators. The experimental environment is similar to the environment of the comprehensive attention test (CAT), but with the inclusion of the IR-UWB radar. The experiment was carried out, according to a predefined scenario. Experiments demonstrate that the proposed indicators can measure movement quantitatively, and can be used as a quantified index to clinically record and compare patient activity. Therefore, this study suggests the possibility of clinical application of radar sensors for standardized diagnosis.

Adherence to treat to target strategy in rheumatoid arthritis: Development of a tool for it assessment

Introduction/Objective: The purpose of the treat to target (T2T) in Rheumatoid Arthritis (RA) is to achieve remission or Low Disease Activity (LDA) according to results from objective activity measurements. To assess the adherence of T2T and to evaluate the application of a tight control T2T-70 and T2T-100 tool, and its association with sustained low disease activity as a measure of outcome. Methods: Sustained LDA (sLDA) was defined when the patient had the Clinical Disease Activity Index (CDAI) lower than 10 during at least 6 months. Measures of adherence to T2T were defined as follows: T2T-70, when therapeutic decisions were accompanied by the measurement of activity by 70% and the interval between visits did not exceed 6 months; And T2T-100, when 100% of the decisions were accompanied with the activity measurement. Results: One hundred and two patients were included. A total of 526 visits were recorded. In 270 visit treatment adjustment was done and 208 (77%) of them were performed according to the CDAI. The frequency of LDAS was 20% (IC95: 12-30). The frequency of T2T-70 and 100 was 62.5% and 42% respectable; that compliance presented a statistically significant association to the achievement of sLDA (p<0.001). Compliance with T2T-70 was also associated with early diagnosis (p:0.009). Conclusion: A global adherence of T2T was 77%. This led to a sustained decrease in disease activity during follow-up. T2T-70 and 100 adherence tool were good, patients who met these criteria reached more sLDA.

Step Activity After Surgical Treatment of Ankle Arthritis

Category: Ankle Arthritis Introduction/Purpose: We used step counts as objective measures of activity as a compliment to patient self-reported outcomes in treatment of ankle arthritis to validate success or failure of treatment. Methods: 234 patients who were treated with ankle arthrodesis or ankle replacement wore step activity monitors before treatment and after treatment at 6 months, 12 months, 24 months and 36 months. Total steps taken as well as low, medium and high activity, sustained activity, and an activity index were measured in each group. In addition, step activity was compared with the subjects’ self-reported outcome using the MFA and SF-36. We measured change from baseline and compared treatment type. Linear mixed-effects regression analysis was used to test for improvement in step activity (the dependent variables) across follow-up (the fixed effect, modeled as 4 dummy variables representing differences from pre-op at 6, 12, 24 and 36 months), with fixed covariates age, sex, body mass index (BMI) and surgical treatment. Results: Both treatment groups improved significantly. Objective and PROM were not parallel. While PROM plateaued at 6 months, steps continued to increase at 36 months. Step counts increases did correlate with improving PROM however. Patients undergoing arthrodesis had slower improvement than arthroplasty patients with greater differences in the early stages of recovery (i.e., 6 and 12-month post-op) than at 36 months where improvements were similar across groups. (See table 2 for data). The trajectory of recovery was different but there were no significant differences in improvement by surgery procedure. Conclusion: Patients increase the number and the intensity of steps after treatment. Improvement after arthrodesis and ankle replacement follow different trajectories. For step totals, high intensity steps and the sustained activity metrics, arthroplasty patients showed more improvement than arthrodesis patients early in recovery. Step data are consistent with patient reported outcomes but do not parallel them. Unlike PROM which improve dramatically in the first six months then plateau, step activity demonstrated mild or no improvement at 6 months but later had improvement that increased gradually across follow-up out to three years. Objective outcome measures add value to measurement of treatment outcomes.

Does context predict psychological states and activity? An ecological momentary assessment pilot study of adolescents

ObjectivesThis study examined contextual variables of location, vegetation, weather, safety, and traffic as predictors of affect, feeling states, and activity in order to gain preliminary understanding of relationships relevant to adolescent health. DesignThis is an ecological momentary assessment pilot study of adolescents. MethodTwenty-six adolescents ages 13–18 completed four daily surveys on a smartphone and wore an accelerometer over 20 days. Surveys collected data about context, affect, and feeling states while the accelerometer provided objective activity measurements. ResultsSignificant relationships emerged between weather and MVPA, sedentary behavior, positive affect, negative affect, energy, and fatigue. Findings were also significant for the contextual predictor of location with sedentary behavior, positive affect, negative affection, energy, and fatigue. Within-person (WP) vegetation was associated with positive affect and energy and WP traffic was associated with positive affect, negative affect, and energy. WP safety and between-person safety were both significantly related to negative affect. ConclusionsEcological momentary assessment of contextual variables may be important in understanding these variables' associations with psychological and activity variables, and should continue to be measured in this way to inform comprehensive health behavior models.

Using digital biomarkers as objective measures of activity and effort related to caregiving. (P6.195)

Using digital biomarkers as objective measures of activity and effort related to caregiving. (P6.195)

Physical activity, visual impairment, and eye disease.

Numerous studies have demonstrated physical activity is a strong factor in overall health and well-being, and a growing body of literature, reviewed herein, suggests that several eye conditions, including glaucoma, age-related macular degeneration, and diabetic retinopathy, are associated with lower activity levels. Likewise, physical activity levels are lower in persons with worse vision. Research in this area has utilized both self-reported physical activity measures as well as objective measures of activity (i.e., accelerometers), each of which have their own strengths and limitations. Putative mechanisms explaining the association of various eye conditions with physical activity are discussed. It is possible that activity restriction occurs as a downstream consequence of eye disease/visual impairment, that activity restriction causes eye disease/visual impairment, or that causality is bidirectional; evidence supporting each of these theories is put forth. An improved understanding of the relationship between physical activity and eye disease will highlight potential secondary health risks resulting from eye disease, and can help determine whether activity might serve as a readily available preventative measure to prevent specific eye conditions.

Objective Measures of Activity in the Elderly: Distribution and Associations With Demographic and Health Factors

BackgroundLittle is known about the distribution of activity over the full 24-hour spectrum in late old age and its association with demographic and health factors. Therefore, we aimed to evaluate the distribution of physical activity (PA), sedentary behavior, and sleep, and associated factors in the elderly population. MethodsOur study included 1210 participants (51.9% women) aged 70–94 years [mean age 77.5 years, standard deviation (SD) 5.0] from the population-based Rotterdam Study. Participants wore a triaxial accelerometer (GENEActiv) around the wrist for 7 days between July 2014 and June 2016. We examined if PA, sedentary behavior, and sleep differed by age, sex, body mass index (BMI), smoking status, alcohol consumption, education, season, functional capacity, marital status, presence of chronic disease, and use of sleep medication. ResultsMean total PA, expressed in milli-gravity (mg) units, was slightly higher for women (20.3, SD 5.6) than for men (19.3, SD 5.2, P < .01). Mean (SD) daily duration spent in sedentary behavior and light and moderate-to-vigorous PA was 13.3 (1.5) h/d, 147.5 (31.5) min/d, and 75.0 (25.5) min/d, respectively, among women; and 13.8 (1.6) h/d, 140.5 (31.1) min/d, and 71.5 (24.5) min/d, respectively, among men. Women spent on average 6.7 (SD 1.1) h/d sleeping and men 6.6 (1.4) h/d. Across increasing categories of age and BMI and in participants with chronic disease and disability, time spent in light and moderate-to-vigorous PA was decreased. Higher age and BMI were associated with more sedentary time. In addition, obese men spent slightly more time sleeping than their normal weight counterparts and women spent slightly less time sleeping in the summer than in spring. ConclusionsPA and sedentary behavior in the elderly differed by sex, age, BMI, prevalence of chronic disease, and disability, whereas there were no clear patterns for sleep. On average, our participants spent up to 79.5% of their time awake being sedentary and 7%–8% in moderate-to-vigorous PA. Replacing sedentary behavior with light PA would be a good starting point for those with the lowest level of PA. Older adults, those with high BMI and worse health could benefit from targeted interventions to increase PA.