The interface of medical devices and pharmaceuticals: Part I

This two-part article considers the complexities of developing and commercialising combination products using examples from experience with drug-eluting stents and drug-eluting beads. Part I discusses the technical challenges of developing these products.

Effects of Cognitive Training on Change in Accuracy in Inductive Reasoning Ability

We investigated cognitive training effects on accuracy and number of items attempted in inductive reasoning performance in a sample of 335 older participants (M = 72.78 years) from the Seattle Longitudinal Study. We assessed the impact of individual characteristics, including chronic disease. The reasoning training group showed significantly greater gain in accuracy and number of attempted items than did the comparison group; gain was primarily due to enhanced accuracy. Reasoning training effects involved a complex interaction of gender, prior cognitive status, and chronic disease. Women with prior decline on reasoning but no heart disease showed the greatest accuracy increase. In addition, stable reasoning-trained women with heart disease demonstrated significant accuracy gain. Comorbidity was associated with less change in accuracy. The results support the effectiveness of cognitive training on improving the accuracy of reasoning performance.

Age group and health status effects on health behavior change

The authors explored health behavior change during 5 years, considering age/cohort, health status, and gender effects. The authors divided the sample (n = 1,064) into 4 age/cohort groups: young adults (n = 139; 19-42 years), middle-aged adults (n = 386; 43-62 years), young-old adults (n = 296; 63-72 years), and old-old adults (n = 243; 73+ years) and health status: cardiovascular disease and physical disability. Smoking and seat belt behaviors remained stable, whereas alcohol, food consumption, food preparation, physical activity, dental, and medical behaviors showed change. Change in health behaviors differed by age/cohort group and health status for food consumption, food preparation, and medical care, primarily showing negative change for old-old adults and positive change for individuals with cardiovascular disease. Health behavior interventions need to focus on the old-old, individuals with physical disability, and on smoking and seat belt use. These specific populations and behaviors need to be targeted to promote positive health behavior change, to limit future onsets of disability and morbidity, and to prevent the occurrence of premature death.

Cognitive Training Gain as a Predictor of Mental Status

We examined the association of proximal and distal training gain to subsequent mental status ratings in 302 participants (M = 76.62 years) trained on inductive reasoning or spatial orientation in the Seattle Longitudinal Study. Only training effects on reasoning ability were predictive of mental status group membership. Participants subsequently rated as probably demented did not significantly differ from nondemented participants in magnitude of reasoning training gain 14 years prior to assessment, but they did 7 years prior to status ratings. Proximal training gain 1 year prior to assessment was 0.40 SD for nondemented participants, compared with 0.25 and 0.10 SD for at-risk and probably demented participants, respectively. The combination of reasoning ability training and increased proximal training gain on reasoning ability was associated with a decreased likelihood of being rated as probably demented.

Long-term effects of cognitive training on everyday functional outcomes in older adults

CONTEXT

Cognitive training has been shown to improve cognitive abilities in older adults but the effects of cognitive training on everyday function have not been demonstrated.

OBJECTIVE

To determine the effects of cognitive training on daily function and durability of training on cognitive abilities.

DESIGN, SETTING, AND PARTICIPANTS

Five-year follow-up of a randomized controlled single-blind trial with 4 treatment groups. A volunteer sample of 2832 persons (mean age, 73.6 years; 26% black), living independently in 6 US cities, was recruited from senior housing, community centers, and hospitals and clinics. The study was conducted between April 1998 and December 2004. Five-year follow-up was completed in 67% of the sample.

INTERVENTIONS

Ten-session training for memory (verbal episodic memory), reasoning (inductive reasoning), or speed of processing (visual search and identification); 4-session booster training at 11 and 35 months after training in a random sample of those who completed training.

MAIN OUTCOME MEASURES

Self-reported and performance-based measures of daily function and cognitive abilities.

RESULTS

The reasoning group reported significantly less difficulty in the instrumental activities of daily living (IADL) than the control group (effect size, 0.29; 99% confidence interval [CI], 0.03-0.55). Neither speed of processing training (effect size, 0.26; 99% CI, -0.002 to 0.51) nor memory training (effect size, 0.20; 99% CI, -0.06 to 0.46) had a significant effect on IADL. The booster training for the speed of processing group, but not for the other 2 groups, showed a significant effect on the performance-based functional measure of everyday speed of processing (effect size, 0.30; 99% CI, 0.08-0.52). No booster effects were seen for any of the groups for everyday problem-solving or self-reported difficulty in IADL. Each intervention maintained effects on its specific targeted cognitive ability through 5 years (memory: effect size, 0.23 [99% CI, 0.11-0.35]; reasoning: effect size, 0.26 [99% CI, 0.17-0.35]; speed of processing: effect size, 0.76 [99% CI, 0.62-0.90]). Booster training produced additional improvement with the reasoning intervention for reasoning performance (effect size, 0.28; 99% CI, 0.12-0.43) and the speed of processing intervention for speed of processing performance (effect size, 0.85; 99% CI, 0.61-1.09).

CONCLUSIONS

Reasoning training resulted in less functional decline in self-reported IADL. Compared with the control group, cognitive training resulted in improved cognitive abilities specific to the abilities trained that continued 5 years after the initiation of the intervention.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00298558.

Competence in everyday activities as a predictor of cognitive risk and mortality

This study examined the association of a performance-based measure of everyday functioning with clinically meaningful outcomes. Elderly participants in a prospective study of dementia were assessed at two occasions on the Everyday Problems Test for Cognitively Challenged Elderly (EPCCE), a performance-based measure of everyday functioning. Older adults who remained cognitively intact performed approximately 0.66 SD units higher on the EPCCE at both occasions than elders rated as impaired, when covarying on age, education, gender, and cognitive status. Relative to the nonimpaired participants, decline in EPCCE performance over a 2-year interval was significantly greater for impaired participants and those participants who transitioned from nonimpaired to impaired over the course of the study. Increased risk of mortality was associated with lower baseline scores and decline in EPCCE performance even after controlling for demographic variables and performance on the Mini-Mental State Examination. Given the clinical importance of identifying "at risk" elders for impairment, the findings from this study provide initial evidence for the predictive utility of performance-based measures of everyday functioning.

In-home cognitive training with older married couples: individual versus collaborative learning

Research has demonstrated that older adults' cognitive performance can be enhanced via formal intervention, as well as more informal intervention including collaboration or working with a partner. The current study investigated the effects of an inductive reasoning training program adapted for in-home use among older adults assigned to individual training (n = 30), collaborative training (n = 34), or a no-treatment control group (n = 34). The training consisted of 10 sessions, and all participants completed a pretest followed by a post-test 6 weeks later. Findings suggest that older adults could effectively "train themselves" without the guidance of a formal instructor. The results, however, did not indicate immediate added benefit in reasoning performance for collaborative versus individual training using the current reasoning program.

Congruence of medication information from a brown bag data collection and pharmacy records: findings from the Seattle longitudinal study

The validity of health information obtained through participants' reports of current medications (e.g., the brown bag method) is an important, but under-studied, area. In the current study, we examined the congruence of medication reports from a brown bag data collection with the pharmacy prescription records for 1430 participants (ages 23 to 97 years) of the seventh wave of the Seattle Longitudinal Study. Overall, the congruence of the brown bag data and pharmacy records was high. Congruence was better for younger participants, healthier participants, and for medications taken for serious conditions or on a regular basis. When the focus is on assessing participants' medications at a specific point in time (e.g., on the day of testing), brown bag data may provide more complete information than pharmacy records. Age and health status of the participants as well as the type of medications of interest should be considered when determining the validity of medication information reported by participants.

Extending neuropsychological assessments into the primary mental ability space

A battery of 17 neuropsychological tests (including the CERAD battery) and 17 psychometric ability tests were administered to a sample of 499 participants of the Seattle Longitudinal study who had been given the psychometric ability tests seven and 14 years earlier. The neuropsychological tests were projected into a 5-factor psychometric ability space by means of extension analysis. The concurrent regressions of the neuropsychology tests on the psychometric ability tests were then used to estimate neuropsychology test scores from the psychometric ability tests administered in 1984, 1991 and 1998. Neuropsychologists then rated the study participants as either normal, suspect or cognitively impaired in 1998. Changes in estimated test scores were computed over seven and fourteen years. Significant odds ratios between normal and cognitively impaired groups were found for all neuropsychological tests over the proximal period and for most tests over the 14-year period. Similar findings occurred for the odds ratios between the normal and suspect groups for the most proximal 7-year changes.

The use of rhodamine 6G and fluorescence microscopy in the evaluation of phospholipid-based polymeric biomaterials

A technique is described that allows the staining and subsequent visualization of polymers that contain the phosphorylcholine (PC) group. These materials are useful as bulk materials or coatings for the fabrication of medical devices. The staining method employs rhodamine 6G, which can be simply and rapidly applied to the polymer coating and imaged using fluorescence microscopy. The specificity of the staining for the PC polymers makes this technique suitable for the evaluation of a wide range of substrates and provides qualitative information on coating uniformity, coverage and morphology. It can be used to examine the durability of, and defects in, the coating. Statistical analysis of the fluorescent intensity by measuring the pixel value during imaging can allow for the method to be used as a quality control tool.

An Historical Framework for Cohort Differences in Intelligence

This article reviews key issues regarding the controversy on the direction and magnitude of cohort differences in intelligence. Data from the Seattle Longitudinal Study (SLS) illustrate why differences must be studied across multiple cohorts and multiple chronological ages. Differential cohort patterns for multiple dimensions of intelligence are described. A conceptual framework is suggested for the identification of historical influences important for developmental study of cohort differences.

The Revised Observed Tasks of Daily Living: A Performance-Based Assessment of Everyday Problem Solving in Older Adults

The Revised Observed Tasks of Daily Living (OTDL-R), a performance-based test of everyday problem solving, was administered to a sample of community-dwelling older adults. The OTDL-R included nine tasks, representing medication use, telephone use, and financial management. The OTDL-R had a desirable range of difficulty and satisfactory internal consistency and showed a relatively invariant pattern of relations between measured tasks and the underlying latent dimensions they represent across White and non-White subsamples. The OTDL-R also correlated significantly with age, education, self-rated health, a paper-and-pencil measure of everyday problem solving, and measures of basic cognitive functioning. Thus, the OTDL-R is a reliable and valid objective measure of everyday problem solving that has great practical utility for assessing performance in diverse populations.

Congruence of self-reported medications with pharmacy prescription records in low-income older adults

PURPOSE

This study examined the congruence of self-reported medications with computerized pharmacy records.

DESIGN AND METHODS

Pharmacy records and self-reported medications were obtained for 294 members of a state pharmaceutical assistance program who also participated in ACTIVE, a clinical trial on cognitive training in nondemented elderly persons. The average age of the sample participants was 74.5 years (range = 65-91); 87.8% were females.

RESULTS

Congruence between self-report and pharmacy data was generally high. Self-reports omitted drug classes in the pharmacy records less often than the pharmacy records did not include self-reported drug classes. The percentage of individuals with perfect agreement between self-reports and pharmacy records varied from 49% for major drug classes to 81% for specific cardiovascular and central nervous system drugs. Within a drug class, agreement tended to be higher for individuals without a prescription in that class. Poorer health was consistently related to poorer self-report of medications.

IMPLICATIONS

Self-reported medications are most likely to be congruent with pharmacy records for drugs prescribed for more serious conditions, for more specific classes of drugs, and for healthier individuals.

The Seattle longitudinal study: relationship between personality and cognition

This article reviews the history, measures and principal findings of the Seattle Longitudinal Study. This study began in 1956 focusing upon age differences and age changes in cognitive abilities. Its sampling frame is a large HMO in the Pacific Northwest. The study has been expanded to investigate various influences on cognitive aging including, cognitive styles, personality traits, life styles, and family environment. Current interest is also in the early detection of risk for dementia. In addition, this article reports original analyses of the relation of personality dimensions to cognitive abilities (both concurrent and longitudinal). While personality remains relatively stable over the adult life span, modest proportions of variance are shared between various personality traits and the cognitive abilities.

Effects of cognitive training interventions with older adults: a randomized controlled trial

CONTEXT

Cognitive function in older adults is related to independent living and need for care. However, few studies have addressed whether improving cognitive functions might have short- or long-term effects on activities related to living independently.

OBJECTIVE

To evaluate whether 3 cognitive training interventions improve mental abilities and daily functioning in older, independent-living adults.

DESIGN

Randomized, controlled, single-blind trial with recruitment conducted from March 1998 to October 1999 and 2-year follow-up through December 2001.

SETTING AND PARTICIPANTS

Volunteer sample of 2832 persons aged 65 to 94 years recruited from senior housing, community centers, and hospital/clinics in 6 metropolitan areas in the United States.

INTERVENTIONS

Participants were randomly assigned to 1 of 4 groups: 10-session group training for memory (verbal episodic memory; n = 711), or reasoning (ability to solve problems that follow a serial pattern; n = 705), or speed of processing (visual search and identification; n = 712); or a no-contact control group (n = 704). For the 3 treatment groups, 4-session booster training was offered to a 60% random sample 11 months later.

MAIN OUTCOME MEASURES

Cognitive function and cognitively demanding everyday functioning.

RESULTS

Thirty participants were incorrectly randomized and were excluded from the analysis. Each intervention improved the targeted cognitive ability compared with baseline, durable to 2 years (P<.001 for all). Eighty-seven percent of speed-, 74% of reasoning-, and 26% of memory-trained participants demonstrated reliable cognitive improvement immediately after the intervention period. Booster training enhanced training gains in speed (P<.001) and reasoning (P<.001) interventions (speed booster, 92%; no booster, 68%; reasoning booster, 72%; no booster, 49%), which were maintained at 2-year follow-up (P<.001 for both). No training effects on everyday functioning were detected at 2 years.

CONCLUSIONS

Results support the effectiveness and durability of the cognitive training interventions in improving targeted cognitive abilities. Training effects were of a magnitude equivalent to the amount of decline expected in elderly persons without dementia over 7- to 14-year intervals. Because of minimal functional decline across all groups, longer follow-up is likely required to observe training effects on everyday function.

ACTIVE: a cognitive intervention trial to promote independence in older adults

The Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) trial is a randomized, controlled, single-masked trial designed to determine whether cognitive training interventions (memory, reasoning, and speed of information processing), which have previously been found to be successful at improving mental abilities under laboratory or small-scale field conditions, can affect cognitively based measures of daily functioning. Enrollment began during 1998; 2-year follow-up will be completed by January 2002. Primary outcomes focus on measures of cognitively demanding everyday functioning, including financial management, food preparation, medication use, and driving. Secondary outcomes include health-related quality of life, mobility, and health-service utilization. Trial participants (n = 2832) are aged 65 and over, and at entry into the trial, did not have significant cognitive, physical, or functional decline. Because of its size and the carefully developed rigor, ACTIVE may serve as a guide for future behavioral medicine trials of this nature.

Memorability functions in verbal memory: a longitudinal approach

Middle-aged (N = 252, M = 39.91), young-old (N = 486, M = 60.77), and old-old (N = 137, M = 74.42) participants in the Seattle Longitudinal Study were tested on two occasions on their recall of a 20-item word list. Proportions of participants in each group correctly recalling each word-unit served as the dependent measure. Word-unit scores obtained in 1991 were regressed on those from 1984, yielding linear functions that varied by age group. Each set of word-unit scores (three groups on two occasions) was then regressed on word familiarity, imageability, primacy, and recency. The relative influence of each of these variables on memorability was then compared, both between and within cohorts. Primacy and familiarity were consistently strong predictors. Imageability and recency were predictive of memorability in the middle-aged group, but less so in the young-old, and not at all in the old-old group. Results and possible implications are discussed.

Cognitive and sociodemographic risk factors for mortality in the Seattle Longitudinal Study

The relationship between cognitive function and survivorship was examined in a community-dwelling sample. Survival analysis was used to examine how level and change in intellectual functioning, verbal memory, perceptual speed, and psychomotor speed were related to mortality in a sample of 601 individuals who subsequently died (decedents; n = 342 men; n = 259 women; M = 73.81 years of age) and a control group of 609 survivors (n = 296 men; n = 313 women; M = 71.96). The sample of survivors was selected to be of similar age and to have a similar level of education as the decedents. Individuals in the lowest 25th percentile of performance (crystallized abilities, visualization abilities, verbal memory, and perceptual and psychomotor speed) had a significant risk for subsequent mortality compared to individuals in the highest 25th percentile. However, after adjusting for demographic variables and psychomotor speed, only perceptual speed remained a significant risk factor for mortality. Significant 7-year declines (lowest 25th percentile) in measurements of Verbal Meaning, Spatial Ability, Reasoning Ability, and Psychomotor Speed were risk factors for subsequent mortality relative to those who had the least amount of decline. The relationship between mortality and cognitive function tended to be a specific rather than a pervasive phenomenon, even after adjusting for sociodemographic factors and psychomotor speed. Decrease in cognitive performance tended to be a better predictor of subsequent mortality than was the level of cognitive performance.

Everyday problem solving among individuals with Alzheimer's disease

Loss of functioning on complex tasks of daily living is an early indicator of dementia. The performance of 65 older adults with mild to moderate levels of Alzheimer's disease was examined on the Everyday Problems Test for the Cognitively Challenged Elderly (EPCCE), self-report inventories of functional performance, and a broad battery of clinical and neuropsychological measures. The EPCCE was designed to assess older adults on a set of complex tasks of daily living that involved not only global cognitive processes, but also higher-order executive functions. Participants solved an average of 45% of EPCCE tasks with significant differences in scores by disease severity. Performance was significantly related to global cognitive functioning and disease severity, and in particular to executive functions. Significant additional variance was accounted for by these executive functions beyond the variance accounted for by global cognitive measures.

Longitudinal invariance of adult psychometric ability factor structures across 7 years

The hypothesis that psychometric ability tests retain equivalent factor structures across a 7-year interval was examined in a sample of 984 persons (disaggregated into 6 cohort groups: M ages at first test = 32, 46, 53, 60, 67, and 76), assessed in 1984 and 1991 as part of the Seattle Longitudinal Study. A best fitting measurement model was estimated for 20 psychometric tests marking the 6 primary abilities of Inductive Reasoning, Spatial Orientation, Perceptual Speed, Numeric Facility, Verbal Ability, and Verbal Recall. Gender was partialed out at the variable level by including a gender factor. Weak factorial invariance over time was demonstrated for all cohorts. Configural invariance could be demonstrated across all cohort groups. However, weak factorial invariance across groups could be accepted for all but the youngest and oldest groups. Latent means were modeled for the accepted solutions across time and cohort groups.

Everyday cognitive competence in elderly persons: conceptual issues and empirical findings

This article focuses on everyday cognitive competence as a critical aspect of functional health. Everyday cognitive competence is defined as the ability to perform adequately those cognitively complex tasks considered essential for living on one's own in this society. A major challenge for those involved in assessment and judgment of competence is to define the critical domains of functional abilities associated with living independently. Prior research on the instrumental activities of daily living (IADLs) may be particularly useful. Findings from our research on a measure assessing everyday cognitive competence within each of the IADL domains are presented. Elderly persons' performance on the measure of everyday cognition relate to behavioral observations of those subjects performing similar activities in their home and to self and spousal IADL ratings. Seven-year longitudinal data indicate that there is relatively modest decline in performance on cognitively complex everyday tasks during the 60s, but that steeper patterns of normative decline are found in the late 70s and 80s.

Everyday problem solving in older adults: observational assessment and cognitive correlates

Older adults' ability to solve practical problems in 3 domains of daily living was assessed using a new measure of everyday problem solving, the Observed Tasks of Daily Living (OTDL). Findings showed that the OTDL formed internally consistent scales representing 3 distinct factors of everyday problem solving. Moreover, the OTDL showed convergent validity with related scales of a paper-and-pencil test. Older adults' performance on the OTDL was significantly correlated with their scores on measures of basic mental abilities. Path analysis showed that age affected older adults' performance on the OTDL directly and indirectly via cognitive abilities. Participants' education and health affected their everyday competence indirectly through cognitive abilities. The effects of perceptual speed and memory span were mediated by fluid and crystallized intelligence.

Dimensionality of everyday problem solving in older adults

This study investigated individual differences in older adults' everyday problem-solving performance using 3 instruments. Past research, typically using only single measures, has yielded a multitude of findings regarding age effects in everyday problem solving. The present sample consisted of 111 older adults (44 men, 67 women) who ranged in age from 68 to 94 years. Confirmatory factor analyses revealed that, within each of the 3 instruments, subscales representing particular content domains could be reliably identified. There was, however, little relation between the different instruments, and the measures also differed in their relation with chronological age. These results support the view that everyday problem-solving competence is a multidimensional construct, of which previous investigations may only have studied particular dimensions.