Probabilities of Transition Among Health States for Older Adults

Goal: To estimate the probabilities of transition among self-rated health states for older adults, and examine how they vary by age and sex. Methods: We used self-rated health (Excellent, Very Good, Good, Fair, Poor, Dead) collected in two longitudinal studies of older adults (Mean age 75) to estimate the probability of transition in two years. We used the estimates to project future health for selected cohorts. Findings: These older adults were most likely to be in the same health state 2 years later, but a substantial proportion changed in both directions. Transition probabilities varied by initial health state, age and sex. Men were more likely than women to transition to Excellent or Dead. Women were more likely than men to transition to Good or Fair health. Although women aged 70 will have more years of life and more years of healthy life than men, they also have more years of unhealthy life, and the proportion of remaining life that is healthy is slightly higher for men. When observed and predicted Years of Healthy Life (YHL) were compared in various subgroups, the YHL of persons with less favorable baseline characteristics was lower than predicted, and vice-versa. Differences, however, were small (about 5%). Conclusions: These transition probability estimates can be used to predict the future health of individuals or groups as a function of current age, sex, and self-rated health

Pathways to Disability Income among Persons with Severe, Persistent Psychiatric Disorders

[Excerpt] Harsh skepticism pervades current public debate about who deserves public support and on what basis, particularly regarding the claims of individuals with disabling illness and injury. Heretofore, these claims were accepted, even reservedly, and the needs of such individuals were considered to be legitimate even when they were monitored closely. The Supplemental Security Income (SSI) and Social Security Disability Insurance (SSDI) programs and their recipients have been among the most visible and vulnerable targets of increased scrutiny and shrinking public beneficence. In 1997, congressional legislation redefined SSI eligibility for children, sparked largely by concerns that children have been deployed to engage in a type of public begging by acting crazy in order to secure benefits for their families. Maladaptive behaviors was removed from the mental disorder listings, and the Social Security Administration (SSA) estimates that 135,000 children will lose their benefits after review. In March 1996, Congress eliminated SSI, SSDI, Medicare, and Medicaid benefits for persons whose drug addiction or alcoholism is a prominent cause of disability, and as a result 141,000 recipients have been terminated. The SSA also was ordered to begin another sweeping review of all recipients of disability income. SSA officials reportedly expect this process to produce a termination rate of 14 percent, resulting in an estimated 196,000 additional individuals who would cease to receive SSI and SSDI

A mutant of Neurospora crassa deficient in cytochrome c heme lyase activity cannot import cytochrome c into mitochondria

The nuclear cyt-2-1 mutant of Neurospora crassa is characterized by a gross deficiency of cytochrome c (Bertrand, H., and Collins, R. A. (1978) Mol. Gen. Genet. 166, 1-13). The mutant produces mRNA that can be translated into apocytochrome c in vitro. Apocytochrome c is also synthesized in vivo in cyt-2-1, but it is rapidly degraded and thus does not accumulate in the cytosol. Mitochondria from wild-type cells bind apocytochrome c made in vitro from either wild-type or cyt-2-1 mRNA and convert it to holocytochrome c. This conversion depends on the addition of heme by cytochrome c heme lyase and is coupled to translocation of cytochrome c into the intermembrane space. Mitochondria from the cyt-2-1 strain are deficient in the ability to bind apocytochrome c. They are also completely devoid of cytochrome c heme lyase activity. These defects explain the inability of the cyt-2-1 mutant to convert apocytochrome c to the holo form and to import it into mitochondria

Further Validation of an Individualized Migraine Treatment Satisfaction Measure

AbstractObjectiveTo assess individualized satisfaction with migraine treatment, patient expectations, importance rankings, treatment outcomes, and overall satisfaction were combined using a four-part conceptual model. This article describes the measurement properties of the Migraine Treatment Satisfaction Measure (MTSM) using participants from a randomized controlled trial evaluating a Headache Management Program (HMP).MethodsParticipants completed the first two parts of the MTSM upon enrollment and the final two parts at 6 months. Internal consistency reliability was computed within each of the four modules. Discriminant validity was ascertained using Migraine Disability Assessment Survey (MIDAS), Patient Health Questionnaire-9, and MSFB scores. Convergent validity was established by hypothesized positive correlations between MTSM scores, Medical Outcomes Study Short-Form (SF-36), MIDAS, and Migraine Symptom Frequency Bother (MSFB).ResultsIn total, 124 participants (mean age 45.4 years, 75% women, 59.7% Caucasian) enrolled. Internal consistency for expectations, importance rankings, outcomes, and satisfaction measures was 0.83, 0.95, 0.86, and 0.95, respectively. As the severity of depression increased, MTSM scores decreased significantly. ANOVA between MTSM scores and symptom bothersomeness and symptom frequency tertiles showed a significant decrease in satisfaction in the moderate-to-severe groups. MTSM scores showed expected associations with MSFB scores (−0.301; P < 0.01), MIDAS (−0.267; P < 0.01), general health (0.253; P < 0.05), mental health (0.217; P < 0.05), and vitality subscales of SF-36 (0.214; P < 0.05). Patients in the HMP reported significantly higher MTSM scores (43.2 vs. 31.4; P < 0.001). Patients on triptans reported a significantly higher satisfaction compared to patients on analgesics (39.5 vs. 32.9; P < 0.05).ConclusionThe MTSM is a valid and reliable patient-reported outcome that can be used to evaluate differences in treatment satisfaction associated with migraine therapies

Performance of the Halex in Logitudinal Studies of Older Adults

Goal: The Halex is an indicator of health status that combines self-rated health and activity limitations, which has been used by NCHS to predict future years of healthy life. The scores for each health state were developed based on strong assumptions, notably that a person in excellent health with ADL disabilities is as healthy as a person in poor health with no disabilities. Our goal was to examine the performance of the Halex as a longitudinal measure of health for older adults, and to improve the scoring if necessary. Methods: We used data from the Cardiovascular Health Study (CHS) to compare the relationship of baseline health to health 2 years later. Subject ages ranged from 65 to 103 (mean age 75). A total of 40,827 transitions were available for analysis. We examined whether Halex scores at time 0 were related monotonically to scores two years later, and iterated the original scores to improve the fit over time. Findings: The original Halex scores were not consistent over time. Persons in excellent health with ADL limitations were much healthier 2 years later than people in poor health with no limitations, even though they had been assumed to have identical health. People with ADL limitations had higher scores than predicted. The assumptions made in creating the Halex were not upheld in the data. Conclusions: The new iterated scores are specific to older adults, are appropriate for longitudinal data, and are relatively assumption-free. We recommend the use of these new scores for longitudinal studies of older adults that use the Halex health states

Estimating The Costs And Cost-effectiveness Of Promoting Mammography Screening Among US-based Latinas

Purpose: We characterize the costs and cost-effectiveness of a community health worker (CHW)-based intervention to promote screening mammography among US-based non-adherent Latinas. Methods: The parent study was a randomized controlled trial for 536 Latinas aged 42-74 years old who had sought care within a safety net health center in Western Washington. Participants were block-randomized within clinic to the control arm (usual care) or intervention arm (CHW-led motivational interviewing intervention). We used the perspective of the organization implementing promotional activities to characterize costs and cost-effectiveness. Cost data were categorized as program set-up and maintenance (initial training, booster/annual training) program implementation (administrative activities, intervention delivery); and, overhead/miscellaneous expenses. Cost-effectiveness was calculated as the incremental cost of screening for each additional woman screened between the intervention and control arms. Results: The respective costs per participant for standard care and the intervention arm were $69.96 and$300.99. There were no study arm differences in 1-year QALYs among women who completed a 12-month follow-up survey (intervention= 0.8827, standard care = 0.8841). Most costs pertained to program implementation and administrative activities specifically. The incremental cost per additional woman screened was $2,595.32. Conclusions: Our findings are within the ranges of costs and cost-effectiveness for other CHW programs to promote screening mammography among underserved populations. Our strong study design and focus on non-adherent women provides important strengths to this body of work, especially give implementation and dissemination science efforts regarding CHW-based health promotion for health disparity populations

Incorporating Death into Health-Related Variables in Longitudinal Studies

Background: The aging process can be described as the change in health-related variables over time. Unfortunately, simple graphs of available data may be misleading if some people die, since they may confuse patterns of mortality with patterns of change in health. Methods have been proposed to incorporate death into self-rated health (excellent to poor) and the SF-36 profile scores, but not for other variables. Objectives: (1) To incorporate death into the following variables: ADLs, IADLs, mini-mental state examination, depressive symptoms, body mass index (BMI), blocks walked per week, bed days, hospitalization, systolic blood pressure, and the timed walk. (2) To discuss variables and settings for which this approach is helpful. (3) To use the approach to illustrate the effect of stroke on these variables. Setting: The Cardiovascular Health Study of 5,888 older adults, studied up to nine years. Mean age was 73 at baseline, and 658 had an incident stroke during follow-up. Methods: We categorized each variable, added a category for death, and examined stacked bar graphs over time. We dichotomized each variable into healthy/not healthy, assigning dead to the “not healthy” category, and calculated the probability of being healthy one year later, with the deaths set to zero. Trajectories for the 11 variables in the three years before and after an incident stroke were tabled and plotted. Other transformations were derived and discussed. Results: Graphs that did not account for death were too optimistic. Stroke had an adverse effect on all variables but systolic blood pressure (which improved) and BMI (which showed little change). The short-term effect of stroke was greatest on hospitalization, self-rated health, and IADLs. Alternative coding provided slightly different results. Conclusions: Categories or values for death can be added to a variety of longitudinal variables, permitting a description of an entire cohort’s trajectory over time. These transformations provide an additional approach for longitudinal studies of the health of older adults where some people die

High resolution structural characterisation of laser-induced defect clusters inside diamond

Laser writing with ultrashort pulses provides a potential route for the manufacture of three-dimensional wires, waveguides and defects within diamond. We present a transmission electron microscopy (TEM) study of the intrinsic structure of the laser modifications and reveal a complex distribution of defects. Electron energy loss spectroscopy (EELS) indicates that the majority of the irradiated region remains as $sp^3$ bonded diamond. Electrically-conductive paths are attributed to the formation of multiple nano-scale, $sp^2$-bonded graphitic wires and a network of strain-relieving micro-cracks

Acute Effects of Neuromuscular-Training with Handheld-Vibration on Elbow Joint Position Sense

Context: Clinicians use exercises in rehabilitation to enhance sensorimotor-function, however evidence supporting their use is scarce. Objective: To evaluate acute effects of handheld-vibration on joint position sense (JPS). Design: A repeated-measure, randomized, counter-balanced 3-condition design. Setting: Sports Medicine and Science Research Laboratory. Patients or Other Participants: 31 healthy college-aged volunteers (16-males, 15-females; age=23+3y, mass=76+14kg, height=173+8cm). Interventions: We measured elbow JPS and monitored training using the Flock-of-Birds system (Ascension Technology, Burlington, VT) and MotionMonitor software (Innsport, Chicago, IL), accurate to 0.5°. For each condition (15,5,0Hz vibration), subjects completed three 15-s bouts holding a 2.55kg Mini-VibraFlex dumbbell (Orthometric, New York, NY), and used software-generated audio/visual biofeedback to locate the target. Participants performed separate pre- and post-test JPS measures for each condition. For JPS testing, subjects held a non-vibrating dumbbell, identified the target (90°flexion) using biofeedback, and relaxed 3-5s. We removed feedback and subjects recreated the target and pressed a trigger. We used SPSS 14.0 (SPSS Inc., Chicago, IL) to perform separate ANOVAs (p\u3c0.05) for each protocol and calculated effect sizes using standard-mean differences. Main Outcome Measures: Dependent variables were absolute and variable error between target and reproduced angles, pre-post vibration training. Results: 0Hz (F1,61=1.310,p=0.3) and 5Hz (F1,61=2.625,p=0.1) vibration did not affect accuracy. 15Hz vibration enhanced accuracy (6.5±0.6 to 5.0±0.5°) (F1,61=8.681,p=0.005,ES=0.3). 0Hz did not affect variability (F1,61=0.007,p=0.9). 5Hz vibration decreased variability (3.0±1.8 to 2.3±1.3°) (F1,61=7.250,p=0.009), as did 15Hz (2.8±1.8 to 1.8±1.2°) (F1,61=24.027, p\u3c0.001). Conclusions: Our results support using handheld-vibration to improve sensorimotor-function. Future research should include injured subjects, functional multi-joint/multi-planar measures, and long-term effects of similar training

Reliability, Effect Size, and Responsiveness and Intraclass Correlation of Health Status Measures Used in Randomized and Cluster-Randomized Trials

Background: New health status instruments are described by psychometric properties, such as Reliability, Effect Size, and Responsiveness. For cluster-randomized trials, another important statistic is the Intraclass Correlation for the instrument within clusters. Studies using better instruments can be performed with smaller sample sizes, but better instruments may be more expensive in terms of dollars, lost opportunities, or poorer data quality due to the response burden of longer instruments. Investigators often need to estimate the psychometric properties of a new instrument, or of an established instrument in a new setting. Optimal sample sizes for estimating these properties have not been studied in detail. Methods: We examined the power of a two-sample test as a function of the Reliability, Effect Size, Responsiveness, and Intraclass Correlation of the instrument. We calculated the “cost-effectiveness” of using a 1-item versus a 5-item measure of mental health status. We also used simulation to determine formulas for the sample size needed to estimate the psychometric statistics accurately. Findings: Under the usual model for measurement error, the psychometric statistics are all functions of the same error term. In randomized trials, a poorer instrument can achieve the desired power if the number of persons per treatment group is increased. In cluster-randomized trials, adequate power may be obtained by increasing the number of clusters per treatment group (and often the number of persons per cluster), as well as by choosing a better instrument. The 1-item measure of mental health status may be more cost-effective than the 5-item measure in some settings. Most published psychometric values are situation-specific. Very large samples are required to estimate Responsiveness and the Intraclass Correlation accurately. Conclusion: If the goal is to diagnose or refer individual patients, an instrument with high Validity and Reliability is needed. In settings where the sample sizes can be increased easily, less reliable instruments may be cost-effective. It is likely that many values of published psychometric statistics were derived from samples too small to provide accurate values, or are importantly specific to the setting in which they were derived. Note: A paper based on some of the material in this technical report has been published. (Diehr P, Chen L, Patrick D, Feng Z, Yasui Y. Reliability, effect size, and responsiveness of health status measures in the design of randomized and cluster-randomized trials. Contemporary Clinical Trials. 2005; 26:45-58. B). That paper does not include the material on estimating the sample size required to provide an accurate estimate of the reliability of a new instrument. That material is included in this technical report