Utility of the Actiwatch Spectrum Plus for detecting the outdoor environment and physical activity in children

Purpose To describe the performance of the Actiwatch Spectrum Plus (Philips, Respironics) for determining real world indoor and outdoor environments and physical activity in children. Methods Children wore the device while performing 10 different activities, ranging from sedentary to vigorous physical-activity, and under different indoor and outdoor conditions. Repeated measures ANOVA was implemented via mixed effects modeling to determine illuminance (lux) and physical activity (counts per 15 s, CP15) across conditions. Receiver operator characteristics (ROC) analysis assessed the accuracy to detect indoor versus outdoor settings. Results Illuminance was found to be statistically different across indoor (793 ± 348 lux) and outdoor (4,413 ± 518 lux) conditions (P<.0001), with excellent diagnostic accuracy to detect indoor versus outdoor settings (Area under the ROC Curve, AUC 0.94); 1088 lux was identified as the optimal threshold for outdoor illuminance (sensitivity: 93.0%; specificity: 85.0%). Using published activity ranges, we found that when children were sitting, 94% of the physical-activity readings were classified as sedentary or light. When children were walking, 88% of readings were classified as light, and when children were running, 77% of readings were classified as moderate or vigorous. Conclusion The Actiwatch Spectrum Plus performed well during real world activities in children, showing excellent diagnostic accuracy at 1088 lux as a threshold to detect indoor versus outdoor environments and in categorizing physical activity. (AU)

Utility of the Actiwatch Spectrum Plus for detecting the outdoor environment and physical activity in children.

PURPOSE: To describe the performance of the Actiwatch Spectrum Plus (Philips, Respironics) for determining real world indoor and outdoor environments and physical activity in children. METHODS: Children wore the device while performing 10 different activities, ranging from sedentary to vigorous physical-activity, and under different indoor and outdoor conditions. Repeated measures ANOVA was implemented via mixed effects modeling to determine illuminance (lux) and physical activity (counts per 15 s, CP15) across conditions. Receiver operator characteristics (ROC) analysis assessed the accuracy to detect indoor versus outdoor settings. RESULTS: Illuminance was found to be statistically different across indoor (793 ± 348 lux) and outdoor (4,413 ± 518 lux) conditions (P<.0001), with excellent diagnostic accuracy to detect indoor versus outdoor settings (Area under the ROC Curve, AUC 0.94); 1088 lux was identified as the optimal threshold for outdoor illuminance (sensitivity: 93.0%; specificity: 85.0%). Using published activity ranges, we found that when children were sitting, 94% of the physical-activity readings were classified as sedentary or light. When children were walking, 88% of readings were classified as light, and when children were running, 77% of readings were classified as moderate or vigorous. CONCLUSION: The Actiwatch Spectrum Plus performed well during real world activities in children, showing excellent diagnostic accuracy at 1088 lux as a threshold to detect indoor versus outdoor environments and in categorizing physical activity.

Dioptric differences between clinically determined and metric-optimised refractions for adults with Down syndrome.

PURPOSE: Refractions based on the optimisation of single-value wavefront-derived metrics may help determine appropriate corrections for individuals with Down syndrome where clinical techniques fall short. This study compared dioptric differences between refractions obtained using standard clinical techniques and two metric-optimised methods: visual Strehl ratio (VSX) and pupil fraction tessellated (PFSt), and investigated characteristics that may contribute to the differences between refraction types. METHODS: Thirty adults with Down syndrome (age = 29 ± 10 years) participated. Three refractive corrections (VSX, PFSt and clinical) were determined and converted to vector notation (M, J0 , J45 ) to calculate the dioptric difference between pairings of each type using a mixed model repeated measures approach. Linear correlations and multivariable regression were performed to examine the relationship between dioptric differences and the following participant characteristics: higher order root mean square (RMS) for a 4 mm pupil diameter, spherical equivalent refractive error and Vineland Adaptive Behavior Scales (a measure of developmental ability). RESULTS: The least squares mean estimates (standard error) of the dioptric differences for each pairing were as follows: VSX versus PFSt = 0.51 D (0.11); VSX versus clinical = 1.19 D (0.11) and PFSt versus clinical = 1.04 D (0.11). There was a statistically significant difference in the dioptric differences between the clinical refraction and each of the metric-optimised refractions (p < 0.001). Increased dioptric differences in refraction were correlated with increased higher order RMS (R = 0.64, p < 0.001 [VSX vs. clinical] and R = 0.47, p < 0.001 [PFSt vs. clinical]) as well as increased myopic spherical equivalent refractive error (R = 0.37, p = 0.004 [VSX vs. clinical] and R = 0.51, p < 0.001 [PFSt vs. clinical]). CONCLUSIONS: The observed differences in refraction demonstrate that a significant portion of the refractive uncertainty is related to increased higher order aberrations and myopic refractive error. Methodology surrounding clinical techniques and metric-optimisation based on wavefront aberrometry may explain the difference in refractive endpoints.

Baseline characteristics in the Israel refraction, environment, and devices (iREAD) study.

The purpose of this study is to present baseline data from a longitudinal study assessing behavioral factors in three groups of boys in Israel with varying myopia prevalence. Ultra-Orthodox (N = 57), religious (N = 67), and secular (N = 44) Jewish boys (age 8.6 ± 1.4 years) underwent cycloplegic autorefraction and axial-length measurement. Time-outdoors and physical-activity were assessed objectively using an Actiwatch. Ocular history, educational factors, and near-work were assessed with a questionnaire. Group effects were tested and mixed effects logistic and linear regression were used to evaluate behaviors and their relationship to myopia. The prevalence of myopia (≤ - 0.50D) varied by group (ultra-Orthodox: 46%, religious: 25%, secular: 20%, P < 0.021). Refraction was more myopic in the ultra-Orthodox group (P = 0.001). Ultra-Orthodox boys learned to read at a younger age (P < 0.001), spent more hours in school (P < 0.001), spent less time using electronic devices (P < 0.001), and on weekdays, spent less time outdoors (P = 0.02). Increased hours in school (OR 1.70) and near-work (OR 1.22), increased the odds of myopia. Being ultra-Orthodox (P < 0.05) and increased near-work (P = 0.007) were associated with a more negative refraction. Several factors were associated with the prevalence and degree of myopia in young boys in Israel, including being ultra-Orthodox, learning to read at a younger age, and spending more hours in school.

Heart Failure-Type Symptom Score Trajectories in CKD: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study.

RATIONALE & OBJECTIVE: Quality of life in chronic kidney disease (CKD) is impaired by a large burden of symptoms including some that overlap with the symptoms of heart failure (HF). We studied a group of individuals with CKD to understand the patterns and trajectories of HF-type symptoms in this setting. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 3,044 participants in the Chronic Renal Insufficiency Cohort (CRIC) without prior diagnosis of HF. PREDICTORS: Sociodemographics, medical history, medications, vital signs, laboratory values, echocardiographic and electrocardiographic parameters. OUTCOME: Trajectory over 5.5 years of a HF-type symptom score (modified Kansas City Cardiomyopathy Questionnaire [KCCQ] Overall Summary Score with a range of 0-100 where<75 reflects clinically significant symptoms). ANALYTICAL APPROACH: Latent class mixed models were used to model trajectories. Multinomial logistic regression was used to model relationships of predictors with trajectory group membership. RESULTS: Five trajectories of KCCQ score were identified in the cohort of 3,044 adults, 45% of whom were female, and whose median age was 61 years. Group 1 (41.7%) had a stable high score (minimal symptoms, average score of 96); groups 2 (35.6%) and 3 (15.6%) had stable but lower scores (mild symptoms [average of 81] and clinically significant symptoms [average of 52], respectively). Group 4 (4.9%) had a substantial worsening in symptoms over time (mean 31-point decline), and group 5 (2.2%) had a substantial improvement (mean 33-point increase) in KCCQ score. A majority of group 1 was male, without diabetes or obesity, and this group had higher baseline kidney function. A majority of groups 2 and 3 had diabetes and obesity. A majority of group 4 was male and had substantial proteinuria. Group 5 had the highest proportion of baseline cardiovascular disease (CVD). LIMITATIONS: No validation cohort available, CKD management changes in recent years may alter trajectories, and latent class models depend on the missing at random assumption. CONCLUSIONS: Distinct HF-type symptom burden trajectories were identified in the setting of CKD, corresponding to different baseline characteristics. These results highlight the diversity of HF-type symptom experiences in individuals with CKD.

Distinctive kidney function trajectories following left ventricular assist device implantation.

BACKGROUND: The aim of this study was to assess for distinct kidney function trajectories following left ventricular assist device (LVAD) placement. Cohort studies of LVAD recipients demonstrate that kidney function tends to increase early after LVAD placement, followed by decline and limited sustained improvement. Inter-individual differences in kidney function response may be obscured. METHODS: We identified continuous flow LVAD implantations in US adults (2016-2017) from INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support). Primary outcomes were estimated glomerular filtration rate (eGFR) trajectories pre-implantation to ∼12 months. Latent class mixed models were applied to primary and validation samples. Clinical differences among trajectory groups were investigated. RESULTS: Among 4,615 LVAD implantations, 5 eGFR trajectory groups were identified. The 2 largest groups (Groups 1 and 2) made up >80% of the cohort, and were similar to group average trajectories previously reported, with early eGFR rise followed by decline and stabilization. Three novel trajectory groups were found: worsening followed by sustained low kidney function (Group 3, 10.1%), sustained improvement (Group 4, 3.3%), and worsening followed by variation (Group 5, 1.7%). These groups differed in baseline characteristics and outcomes. Group 4 was younger and had more cardiogenic shock and pre-implantation dialysis; Group 3 had higher rates of pre-existing chronic kidney disease, along with older age. CONCLUSIONS: Novel eGFR trajectories were identified in a national cohort, possibly representing distinct cardiorenal processes. Type 1 cardiorenal syndrome may have been predominant in Group 4, and parenchymal kidney disease may have been predominant in Group 3.

Heart failure-type symptom scores in chronic kidney disease: The importance of body mass index.

OBJECTIVES: This analysis sought to determine factors (including adiposity-related factors) most associated with HF-type symptoms (fatigue, shortness of breath, and edema) in adults with chronic kidney disease (CKD). BACKGROUND: Symptom burden impairs quality of life in CKD, especially symptoms that overlap with HF. These symptoms are common regardless of clinical HF diagnosis, and may be affected by subtle cardiac dysfunction, kidney dysfunction, and other factors. We used machine learning to investigate cross-sectional relationships of clinical variables with symptom scores in a CKD cohort. METHODS: Participants in the Chronic Renal Insufficiency Cohort (CRIC) with a baseline modified Kansas City Cardiomyopathy Questionnaire (KCCQ) score were included, regardless of prior HF diagnosis. The primary outcome was Overall Summary Score as a continuous measure. Predictors were 99 clinical variables representing demographic, cardiac, kidney and other health dimensions. A correlation filter was applied. Random forest regression models were fitted. Variable importance scores and adjusted predicted outcomes are presented. RESULTS: The cohort included 3426 individuals, 10.3% with prior HF diagnosis. BMI was the most important factor, with BMI 24.3 kg/m2 associated with the least symptoms. Symptoms worsened with higher or lower BMIs, with a potentially clinically relevant 5 point score decline at 35.7 kg/m2 and a 1-point decline at the threshold for low BMI, 18.5 kg/m2. The most important cardiac and kidney factors were heart rate and eGFR, the 4th and 5th most important variables, respectively. Results were similar for secondary analyses. CONCLUSIONS: In a CKD cohort, BMI was the most important feature for explaining HF-type symptoms regardless of clinical HF diagnosis, identifying an important focus for symptom directed investigations.

Inter-muscular coherence and functional coordination in the human upper extremity after stroke.

Muscle coordination and motor function of stroke patients are weakened by stroke-related motor impairments. Our earlier studies have determined alterations in inter-muscular coordination patterns (muscle synergies). However, the functional connectivity of these synergistically paired or unpaired muscles is still unclear in stroke patients. The goal of this study is to quantify the alterations of inter-muscular coherence (IMC) among upper extremity muscles that have been shown to be synergistically or non-synergistically activated in stroke survivors. In a three-dimensional isometric force matching task, surface EMG signals are collected from 6 age-matched, neurologically intact healthy subjects and 10 stroke patients, while the target force space is divided into 8 subspaces. According to the results of muscle synergy identification with non-negative matrix factorization algorithm, muscle pairs are classified as synergistic and non-synergistic. In both control and stroke groups, IMC is then calculated for all available muscle pairs. The results show that synergistic muscle pairs have higher coherence in both groups. Furthermore, anterior and middle deltoids, identified as synergistic muscles in both groups, exhibited significantly weaker IMC at alpha band in stroke patients. The anterior and posterior deltoids, identified as synergistic muscles only in stroke patients, revealed significantly higher IMC in stroke group at low gamma band. On the contrary, anterior deltoid and pectoralis major, identified as synergistic muscles in control group only, revealed significantly higher IMC in control group in alpha band. The results of muscle synergy and IMC analyses provide congruent and complementary information for investigating the mechanism that underlies post-stroke motor recovery.

Avoidable emergency department visits for rabies vaccination.

BACKGROUND: Administering subsequent doses of rabies vaccine is not a medical emergency and does not require access to emergency department (ED) services. This study reviewed ED visits for rabies postexposure prophylaxis (PEP) to identify avoidable ED visits for subsequent rabies vaccination. METHODS: This retrospective study included patients who received human rabies immune globulin (HRIG) or rabies vaccine at 15 EDs of a multi-hospital health system from 2016 to 2018. All ED visits were classified as initial or non-initial healthcare visits after animal exposure. Emergency department visits for non-initial healthcare were classified as necessary (HRIG administration, worsening symptoms, other emergent conditions, or vaccination during a natural disaster) or avoidable (rabies vaccination only). RESULTS: This study included 145 patients with 203 ED visits (113 initial and 90 non-initial healthcare visits). Avoidable ED visits were identified for 19% (28 of 145) of patients and 66% (59 of 90) of ED visits for non-initial healthcare. Contributing factors for avoidable ED visits were suboptimal ED discharge instructions to return to the ED for vaccination (n = 20 visits) and patients' inability to coordinate outpatient follow-up (n = 17 visits). Patients with previous avoidable ED visits had a 73% probability for unnecessarily returning to the ED for vaccination. The average number of avoidable ED visits observed per patient was 0.41 (95% CI = 0.25 to 0.56). Since the Centers for Disease Control and Prevention reports that 30,000 to 60,000 Americans initiates rabies PEP each year, we estimate that 7500 to 33,600 avoidable ED visits occur for rabies vaccination in the US each year. CONCLUSIONS: One of 5 patients who received rabies PEP in the ED had avoidable ED visits for subsequent rabies vaccination. This study highlights systemic lack of coordination following ED discharge and barriers to accessing rabies vaccine.

Visual Acuity Outcomes in a Randomized Trial of Wavefront Metric-optimized Refractions in Adults with Down Syndrome.

SIGNIFICANCE: This study reports visual acuity outcomes from a clinical trial investigating an objective refraction strategy that may provide a useful tool for practitioners needing additional strategies to identify refractive corrections for adults with intellectual disability. PURPOSE: Determining refractions for individuals with Down syndrome is challenging because of the presence of elevated refractive error, optical aberrations, and cognitive impairment. This randomized clinical trial evaluated the performance of spectacle corrections determined using clinical techniques and objective refractions derived from wavefront aberration measures. METHODS: Thirty adults with Down syndrome had a clinical refraction determined by a single expert examiner using pre-dilation and post-dilation techniques appropriate for this population. Objective refractions were determined from dilated wavefront aberration measures that were processed post-visit to identify refractions that optimized each of two image quality metrics: pupil fraction tessellated and visual Strehl ratio in the spatial domain. The three refractions were dispensed in random order and worn for 2 months each. The primary outcome measure, binocular visual acuity, was obtained by a masked examiner administering a distance logMAR acuity test. To compare treatment types, mean acuity was compared using a two-sided type 3 F test of the treatment effect in a linear mixed-effects regression model, where the final model included fixed effects for treatment, period (1, 2, or 3), and first-order carryover effects. RESULTS: The 2-month estimated least square means in binocular visual acuity (logMAR) were 0.34 (95% confidence interval [CI], 0.25 to 0.39) for clinical refractions, 0.31 (95% CI, 0.25 to 0.36) for pupil fraction tesselated refractions, and 0.33 (95% CI, 0.27 to 0.38) for visual Strehl ratio refractions. No statistically significant treatment effect was observed (F = 1.10, P = .34). CONCLUSIONS: Objective refractions derived from dilated wavefront aberration measures resulted in acuity similar to expert clinician-derived refractions, suggesting that the objective method may be a suitable alternative for patients with Down syndrome.

Evaluation of sleep quality among nursing faculty: Application of the Pittsburgh Sleep Quality Index-A descriptive correlational study.

AIM: The aim of this study was to describe the overall sleep quality, sleep patterns and severity of sleep difficulties among nursing faculty using the Pittsburgh Sleep Quality Index (PSQI). DESIGN: Cross-sectional descriptive and correlational study. METHODS: A survey of faculty recruited from Texas Board of Nursing approved colleges/schools was used. A purposive, convenience sample of 105 faculty completed the PSQI, a reliable and valid instrument, in an online setting. Data was collected from January 2019 through April 2019. RESULTS: Nursing faculty reported sleep difficulty across all components, with more problems in sleep latency, sleep disturbances and subjective sleep quality. Overall, 70.5% of participants were reportedly "poor" sleepers, a salient finding. Faculty experienced poor sleep quality across all academic ranks and age groups. Sleep latency and subjective sleep quality were components that presented higher in severity for the youngest faculty.

Objective Behavioral Measures in Children before, during, and after the COVID-19 Lockdown in Israel.

Studies using questionnaires report that COVID-19 restrictions resulted in children spending significantly less time outdoors. This study used objective measures to assess the impact of pandemic-related restrictions on children's behavior. A total of 19 healthy 8-12-year-old boys were observed before and during social restriction periods. Of these, 11 boys were reassessed after restrictions were lifted. For each session, Actiwatches were dispensed for measures of time outdoors, activity, and sleep. Changes overall and by school status were assessed using signed-rank test and Wilcoxon rank sum tests. During restrictions, children spent significantly less time outdoors (p = 0.001), were less active (p = 0.001), and spent less time engaged in moderate-to-vigorous physical activity (p = 0.004). Sleep duration was not significantly different between sessions (p > 0.99), but bedtime and wake time shifted to a later time during restrictions (p < 0.05 for both). Time outdoors and activity returned close to pre-pandemic levels after restrictions were lifted (p > 0.05 for both). Children's behaviors significantly changed during the COVID-19 pandemic. The reduction in outdoor light exposure is of importance due to the role of light in the etiology of myopia and vitamin D production. The reduction in physical activity may have negative health effects in terms of obesity and depression, although further research is required to ascertain the long-term effects.

A Randomized Trial of Objective Spectacle Prescriptions for Adults with Down Syndrome: Baseline Data and Methods.

SIGNIFICANCE: It is difficult to determine the most efficacious refractive correction for individuals with Down syndrome using routine clinical techniques. New objective methods that optimize spectacle corrections for this population may reduce limitations on daily living by improving visual quality. PURPOSE: This article describes the methods and baseline characteristics of study participants in a National Eye Institute-sponsored clinical trial to evaluate objectively derived spectacle corrections in adults with Down syndrome. Intersession repeatability of the primary outcome measure (distance visual acuity) is also reported. METHODS: Adults with Down syndrome were enrolled into a nine-visit study to compare clinically derived spectacle corrections and two different objective spectacle corrections derived from wavefront aberration data. Spectacle corrections were randomized and dispensed for 2 months each. Distance visual acuity was measured with a Bailey-Lovie-style chart. Intersession repeatability of acuity was established by performing difference versus mean analysis from binocular acuity measures obtained through habitual corrections at visits 1 and 2. RESULTS: Thirty adults (mean ± standard deviation age, 29 ± 10 years) with a large range of refractive errors were enrolled. Presenting visual acuity at visit 1 was reduced (right eye, 0.47 ± 0.20 logMAR; left eye, 0.42 ± 0.17 logMAR). The mean difference between visits 1 and 2 was 0.02 ± 0.06 logMAR, with a coefficient of repeatability (1.96 × within-subject standard deviation) of 0.12 logMAR. CONCLUSIONS: This study seeks to investigate new strategies to determine optical corrections that may reduce commonly observed visual deficits in individuals with Down syndrome. The good intersession repeatability of acuity found in this study (six letters) indicates that, despite the presence of reduced acuity, adults with Down syndrome performed the outcome measure for this clinical trial reliably.

Understanding the Impact of Individual Perceived Image Quality Features on Visual Performance.

Purpose: This study aimed to quantify the impact of blur, contrast, and ghosting on perceived overall image quality (IQ) as well as resultant predicted visual acuity, utilizing simulated acuity charts from objective refraction among eyes of individuals with Down syndrome (DS). Methods: Acuity charts were produced, simulating the retinal image when applying 16 different metric-derived sphero-cylindrical refractions for each eye of 30 adult patients with DS. Fourteen dilated adult observers (normal vision) viewed subsets of logMAR acuity charts displayed on an LCD monitor monocularly through a unit magnification 3-mm aperture telescope. Observers rated features blur, ghosting, and contrast on 10-point scales (10 = poorest) and overall IQ on a 0- to 100-point scale (100 = best) and read each chart until five total letters were missed (logMAR technique). Mixed modeling was used to estimate feature influence on overall perceived IQ and relative acuity (compared with an unaberrated chart), separately. Results: Perceived IQ spanned the entire scale (mean = 59 ± 22) and average reduction in relative acuity was two lines (0.2 ± 0.14 logMAR). Perceived blur, ghosting, and contrast were individually correlated with overall IQ and relative acuity. Blur, contrast, and ghosting exert unique effects on overall perceived IQ (P < 0.05). Blur (b = -.009, P < 0.001) and ghosting (b = -.003, P < 0.001) influence relative acuity over and beyond their effects on overall IQ (b = .001, P < 0.0001) and contrast. Conclusions: Objectively identified refractions would ideally provide high contrast, low blur, and low ghosting. These data suggest that blur and ghosting may be given priority over contrast when improving acuity is the goal. Translational Relevance: Findings may guide objective refraction in clinical care.

Randomized Clinical Trial of Near Visual Performance with Digital Devices Using Spherical and Toric Contact Lenses.

SIGNIFICANCE: Visual demands today incorporate a significant amount of time using digital devices. Results of this randomized crossover study of spherical and toric contact lenses demonstrated that participants were able to read smaller print size more comfortably and preferred toric contact lenses when using digital devices. PURPOSE: The purpose of this study was to assess how toric contact lens correction affects subjective and objective outcomes of astigmatic patients using real-world digital devices. METHODS: Adult participants, aged between 20 and 38 years with -0.75 to -1.50 D of astigmatism were enrolled in this double-masked randomized crossover 10-day study of Alcon Dailies Aqua Comfort Plus Sphere and Toric (Alcon, Geneva, Switzerland) contact lenses. Electronic high- and low-contrast near logMAR visual acuity and contrast sensitivity were tested. Reading performance was assessed using custom iPad applications; one used a reading sentences test, whereas the other analyzed zoom, contrast, and distance with website-based articles. Participants completed the Near Activity Visual Questionnaire and stated their preferred contact lens correction. RESULTS: Thirty seven participants were screened, 35 participants were enrolled, and 34 participants completed the study. Toric lens correction improved near high- and low-contrast visual acuity by 0.5 to 1 full line (P < .0001) and allowed participants to read one line smaller text on the iPad (P = .01). Participants increased the zoom 11% (P = .004) and the contrast 4% (P = .006) more with spherical lenses while reading articles. Participants held the iPad at approximately the same distance, about 33 cm (P = .63). Eighty five percent of participants preferred the toric correction (P < .0001). Participants reported improved satisfaction with toric lens correction (P = .0002) and noticed the most benefit with tasks such as reading small print and labels/instructions. CONCLUSIONS: This study used digital devices to demonstrate realistic benefits of toric contact lens designs for astigmatic patients.

Longitudinal Sensitivity of Alzheimer's Disease Severity Staging.

Understanding Alzheimer's disease (AD) dynamics is essential in diagnosis and measuring progression for clinical decision-making; however, clinical instruments are imperfect at classifying true disease stages. This research evaluates sensitivity and determinants of AD stage changes longitudinally using current classifications of "mild," "moderate," and "severe" AD, using Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog), and the Clinical Dementia Rating-Sum of Boxes (CDR-SB) thresholds. Age and pre-progression rate were significant determinants of AD progression using MMSE alone to stage AD, and pre-progression was found to impact disease progression with CDR-SB. Sensitivity of these instruments for identifying clinical stages of AD to correctly staging a "moderate" level of disease severity for outcomes MMSE, CDR-SB, and ADAS-Cog was 92%, 78%, and 92%, respectively. This research derives longitudinal sensitivity of clinical instruments used to stage AD useful for clinical decision-making. The MMSE and ADAS-Cog provided adequate sensitivity to classify AD stages.

Impact of Pupil Diameter on Objective Refraction Determination and Predicted Visual Acuity.

PURPOSE: Objective refraction based on wavefront aberration measures is a potential tool for patients unable to participate in a subjective refraction, but the selection of a single pupil diameter for determination of the objective refraction may pose challenges. The purpose of this study was to investigate the impact of pupil diameter on determination of objective refractions for adults with and without Down syndrome (DS) and predicted change in acuity with increasing pupil diameter. METHODS: Wavefront error was obtained from 27 adults with DS and 24 controls, and metric-optimized refractions were identified for 4- and 6-mm pupil diameters. Total dioptric difference between refractions for the two pupil sizes was calculated, and repeated measures analysis of variance was used to evaluate differences in refractions. Next, five control observers read acuity charts produced to simulate image quality of each subject if the same refraction was applied for both a 4- and 6-mm pupil diameter. A comparison of acuity with performance on a clear chart was used to calculate letters lost for each chart. Repeated measures analysis of variance was used to test for differences in letters lost from 4- and 6-mm diameters. RESULTS: The dioptric difference between refractions for 4- and 6-mm pupils was significantly greater in subjects with DS (0.51 diopters vs. 0.19 diopters, P = 0.0012). Letters lost for predicted acuity was less for the 4-mm diameter than 6 mm for charts representing DS eyes (6.5 letters vs. 11 letters, P < 0.0001), as well as for typical eyes (4.5 letters vs. 8 letters, P < 0.0001). CONCLUSIONS: Differences between refractions by pupil diameter were similar to the repeatability of subjective refraction. Visual acuity differences were clinically small, suggesting similar performance for objective refractions with increasing pupil diameter. TRANSLATIONAL RELEVANCE: This work quantifies the potential impact of pupil diameter change on the performance of wavefront optimized refractions in clinical patients.

Application of Topographical Keratoconus Detection Metrics to Eyes of Individuals with Down Syndrome.

SIGNIFICANCE: The challenges associated with clinical assessment of individuals with Down syndrome contribute to a wide range of estimates on the prevalence of keratoconus in the Down syndrome population. This work focuses on two topographical indices previously identified with keratoconus detection, applying them to a topographical data set meeting strict sampling criteria. PURPOSE: The purpose of this study was to quantify the level of keratoconus-like topographical morphology in a large sample of eyes from individuals with Down syndrome, as identified by two keratoconus detection metrics: inferior-superior dioptric asymmetry (I-S) and KISA%. Severity of the asymmetry was also cast within the context of established Collaborative Longitudinal Evaluation of Keratoconus study disease severity classification criteria. METHODS: Corneal topography data on both eyes of 140 subjects with Down syndrome and 138 control subjects were collected. Both I-S and KISA% were calculated from the topography data of eyes with sufficient sampling. Steep and flat keratometry data are reported for subjects with measurements on both eyes in the context of values recorded by the Collaborative Longitudinal Evaluation of Keratoconus study in frank keratoconus to examine within-eye and between-eye asymmetry and severity. RESULTS: Keratoconus detection thresholds were exceeded in 20.8% of the eyes of subjects with Down syndrome and 2.2% of the eyes of controls using I-S and 11.8% of the eyes of subjects with Down syndrome and 0.0% of the eyes of controls using KISA%. Examination of the level of intraeye difference between flat and steep keratometry data for individuals with Down syndrome detected as having corneal morphology consistent with moderate keratoconus yields an average of 1.81 D of toricity, whereas the Collaborative Longitudinal Evaluation of Keratoconus study reported 3.28 D of toricity. CONCLUSIONS: Morphology consistent with keratoconus as codified in the detection metrics I-S and KISA% is present in a large percentage of the eyes of individuals with Down syndrome. Differences were observed in the distribution of severity of corneal morphology in individuals with Down syndrome and the keratoconus population at large.

Refining Psychological, Substance Use, and Sociodemographic Predictors of Suicide Ideation and Attempts in a National Multiethnic Sample of Adults, 2008-2013.

The purpose of this study was to examine psychological, substance use, and sociodemographic predictors of 12-month suicide ideation and attempts across six US racial/ethnic groups-white, Latino/a, Black, Asian or Pacific Islander (A/PI), American Indian or Alaska Native (AI/AN), and multiracial adults. Multiple logistic regression analyses were conducted for 218,765 adults who participated in the 2008-2013 National Survey on Drug Use and Health. Overall, commonly cited factors were associated with increased risk for suicide ideation and attempt for some racial/ethnic groups, but not for others. As one example, 12-month depression was associated with 12-month suicide attempt for A/PI, AI/AN, Latino/a, and white, but not for Black or multiracial adults. Alcohol abuse and dependence were also associated with suicide attempt for AI/AN, Black, and white respondents but not for other racial/ethnic groups. Risk factors for suicide ideation and attempt may not increase risk universally. More theoretically supported research is needed.