Biomedical subjects

C M Mitchell

Publications and source records attributed to C M Mitchell.

At least 19 recordsLinked to original sources

PubMed2001

Post-operative endophthalmitis: the application of hazard analysis critical control points (HACCP) to an infection control problem.

Hazard analysis critical control points (HACCP) is a quality assurance system widely used in the food industry to ensure safety. We adopted the HACCP approach when conventional infection control measures had failed to solve an ongoing problem with an increased incidence of postoperative endophthalmitis, and our ophthalmology unit was threatened with permanent cessation of intraocular surgery. Although time-consuming, the result was an entirely new set of protocols for the care of patients undergoing intraocular surgery, the development of an integrated care pathway, and a comprehensive and robust audit programme, which enabled intraocular surgery to continue in a new spirit of confidence. HACCP methodology has so far been little used in healthcare, but it might be usefully applied to a variety of apparently intractable infection control problems.

Cataract Extraction↗

PubMed2001

Sequences of substance use among American Indian adolescents.

OBJECTIVE: To determine whether the predominant pattern of the sequence of use of different classes of substances among a large sample of American Indian (AI) adolescents is consistent with Stage Theory [i.e., (1) alcohol, (2) marijuana, (3) other illicit drugs, and (4) cocaine]. METHOD: Data came from surveys completed by 1,562 AI high school students in 1993. Pairwise comparisons of age of first use for alcohol, marijuana, inhalants, cocaine, and other illicit drugs were examined, as were the prevalence rates of specific sequences of substance use. RESULTS: Thirty-five percent of the AI youths who had used both alcohol and marijuana reported using alcohol first. Seventy-five percent of youths who had used three or more substances reported a sequence of first use that was inconsistent with Stage Theory. However, a general pattern of using alcohol, marijuana, and/or inhalants prior to the use of cocaine and other illicit drugs was observed. Sequences of first use varied by gender, age of first substance use, community, and number of classes of substances used. CONCLUSIONS: To enhance the validity of Stage Theory for AI adolescents, the authors recommend its revision to include alcohol, marijuana, and inhalants as initiating substances.

Adolescent↗

PubMed2000

The latent structure of substance use among American Indian adolescents: an example using categorical variables.

Researchers frequently have only categorical data to analyze and cannot, for theoretical or methodological reasons, assume that the observed variables are discrete representations of an underlying continuous variable. We present latent class analysis as an alternative method of measuring latent variables in these circumstances. Latent class analysis does not require the assumptions of factor analyses about the nature of manifest and latent variables, but does allow the use of more precise model selection than techniques such as cluster analysis. We modeled the lifetime substance use of American Indian youth. The latent class model of American Indian teenagers' substance use had four classes: Abstaining, Predominantly Alcohol, Predominantly Alcohol and Marijuana, and Plural Substance. We then demonstrated the usefulness of this latent variable by using it to differentiate levels of several variables in a manner consistent with Social Cognitive Theory.

Adolescent↗

PubMed2000

Specialized dementia programs in residential care settings.

The authors conducted a telephone survey in 7 states to determine the prevalence of residential care specialized dementia programs (RC-SDPs) and to identify a sample of homes (n = 56) for more detailed study. The 56 homes were site visited, and data were gathered on facility administration, therapeutic environment, and characteristics of 259 randomly selected residents. Comparison data from 138 nursing home Special Care Units (NH-SCUs) and 1,340 of their residents were obtained from 4 studies conducted in the same 7 states. RC-SDPs were smaller, provided a more homelike environment, and had a higher proportion of residents paying privately, compared with NH-SCUs. Mean levels of cognitive and physical impairment among residents were higher in NH-SCUs; prevalences of psychotropic medication use and problem behaviors were similar. Among RC facilities, small homes were more homelike, provided fewer structured activities, and charged less than larger facilities. RC-SDPs include 5 types: small, independently operated homes; multiple small homes with joint administration; larger, all-dementia facilities; SDPs operated within larger, exclusively RC facilities; and RC-SDPs in multilevel facilities.

Aged↗

PubMed1999

Impact on maternal parenting stress of receipt of genetic information regarding risk of diabetes in newborn infants.

Our objective was to investigate whether notification of high-risk status for type 1 diabetes in newborn infants results in an increased maternal-parenting stress level when compared with notification of low-risk status for type 1 diabetes. Maternal parenting stress level was assessed at 5-7 weeks postpartum (baseline) and was reassessed 4-5 months after parents were informed of their newborn infants' genetic screening results (follow-up). Parenting stress level was measured using the total stress score (TSS) of the Parenting Stress Index/Short Form. The outcome variable, change in TSS, was calculated by subtracting the baseline TSS from the follow-up TSS. Demographic variables such as maternal race, maternal age, maternal education level, maternal marital status, child's birth order, and total family income were assessed through a structured phone interview at the time of baseline assessment. The risk factor of interest was the child's human leukocyte antigen (HLA) status for type 1 diabetes, i.e., whether child was at a high or moderate (combined into "high") genetic risk or at a low genetic risk for type 1 diabetes. A sample of 88 mothers (23 with a high-risk child and 65 with a low-risk child) was evaluated. Baseline median TSSs were 65 and 74 for mothers of low-risk infants and mothers of high-risk infants, respectively. Both groups' median TSS decreased between baseline and follow-up. No significant differences were found between change in TSS and maternal age, race, education level, marital status, total family income, or child's birth order. Although the median decrease in TSS was smaller in mothers with a high-risk child when compared with mothers of a low-risk child, this difference was not statistically significant. We did not find an association between newborn's HLA status and change in maternal TSS. The results of this study suggest that notification of high-risk status for type 1 diabetes in newborn infants may not result in an increased level of parenting stress among mothers.

Adult↗

PubMed1999

Marijuana use among American Indian adolescents: a growth curve analysis from ages 14 through 20 years.

OBJECTIVE: To describe the developmental course of marijuana use among a group of American Indian adolescents, aged 14 through 20 years. METHOD: A group of 1,766 American Indian adolescents from 3 culture groups provided repeated measures of 30-day marijuana use twice a year across a 3-year period. Linking 5 age cohorts, hierarchical linear modeling was used to model a curvilinear trajectory of marijuana use. Gender and community differences were examined as well. RESULTS: Support was found for a "maturational" model of marijuana use across time: Use increased in middle adolescence, peaked in later adolescence, and began to decrease in early adulthood. Both gender and community differences in trajectories were significant as well. CONCLUSIONS: Marijuana use among American Indian adolescents follows a clear developmental trajectory. Growth curve analysis can provide an additional tool for studying the effects of interventions that may not be apparent in a traditional evaluation design.

Adolescent↗

PubMed1999

Severe disruptive vocalizers.

OBJECTIVES: To describe the most severe disruptive vocalizers in nursing facilities, in regard to their clinical and behavioral characteristics, staff responses, and treatments used, and to report on their prognosis over 6 months. DESIGN: A longitudinal cohort study. SETTING: One hundred seven skilled nursing facilities. PARTICIPANTS: The 203 residents who were among the two most disruptive vocalizers in their respective facilities and who vocalized at least 2 hours a day. MEASUREMENTS: Telephone interviews of licensed nursing staff who cared for the subjects, conducted at baseline, 2, 4, and 6 months. Data gathered included subject demographics, physical function, diagnoses, medication and restraint use, behavioral problems, vocalization characteristics, treatments used, and status at follow-up. RESULTS: Subjects tended to have dementia, to be dependent in most activities of daily living, to have multiple medical problems, to be physically restrained (48%), and to be taking psychotropic medication (76%). Nearly all (95%) were audible at least 50 feet away, with loudness associated with more severe cognitive impairment (OR 4.90, P = .001). When subjects who primarily made nonverbal noises ("screamers") were compared with those whose predominant expressions were words ("talkers"), hearing impairment, severe cognitive impairment, and greater dependency in activities of daily living characterized the screamers. Staff reported trying a variety of treatments with all subjects, often with little success. Two months after enrollment, 66% of surviving subjects vocalized fewer hours than at baseline, and 45% were rated as improved. Independent predictors of improvement included greater ADL independence, hearing and vision problems, shorter length of stay, urinary incontinence, and use of a treatment other than one-on-one interventions. Nearly one-quarter of subjects (23.4%) died within 6 months. Baseline factors associated independently with a higher probability of death included age, use of activity intervention, physical abusiveness, and absence of wandering. CONCLUSION: Severe disruptive vocalization is associated with severe cognitive and physical impairment and with a high probability of mortality within 6 months. Subcategorization of severe vocalizers by vocalization type or other associated factors may be useful for prognostic and treatment purposes.

Activities of Daily Living↗

PubMed1998

Factors associated with marijuana use among American Indian adolescents.

AIM: To examine the characteristics of marijuana users among a large sample of American Indian high school students. DESIGN: High school survey. SETTING: Seven predominantly American Indian high schools in four communities west of the Mississippi. PARTICIPANTS: 1464 Indian adolescents who: (1) completed a survey in November, 1993, (2) were in grades 9 to 12, (3) were members of one of four Indian tribal groups; and (4) had a complete set of data for these analyses. MEASUREMENTS: Logistic regression models were developed to predict the probability of low-frequency (1-3 times over the last month) and high-frequency (11 or more times) marijuana use. Independent variables included measures of socio-demographics, stressful life events, personal characteristics and beliefs, psychiatric symptomatology and other substance use. FINDINGS: Forty per cent of these American Indian adolescents had used marijuana at least once in the last month. The prevalence of marijuana use varied across the four tribes. Males were no more likely than females to use marijuana at a low frequency, but were more likely to use at a high frequency. The factors associated with marijuana use varied with the frequency of use and by gender. In the final multivariate models, low-frequency marijuana use among females was associated with reporting that peers encouraged alcohol use as well as use of alcohol and stimulants. Among males, low-frequency use was associated with greater positive alcohol expectancies, lower grades in school and alcohol use. While high-frequency marijuana use was associated with use of alcohol, stimulants and cocaine among females, such use was associated with higher scores on the antisocial behavior scale as well as the use of alcohol, stimulants and cocaine among males. Overall, the strongest associations were with the use of alcohol and other illicit substances. CONCLUSION: Low-frequency and high-frequency marijuana use are distinct patterns of use and have different correlates across genders. Marijuana use among American Indian adolescents is a complex phenomenon that is best understood within the context of other substance use.

Adolescent↗

PubMed1998

Environmental correlates of resident agitation in Alzheimer's disease special care units.

OBJECTIVE: To determine the point prevalence of agitated behaviors in a representative sample of Alzheimer's disease Special Care Units, and to determine the extent to which agitation is associated with aspects of the treatment environment. DESIGN: A cross-sectional study in which nonparticipant observers recorded 3723 observations of resident behaviors in 53 Alzheimer's disease Special Care Units. Observational data were gathered on the physical environment and staff treatment in these settings, and resident characteristics were extracted from a data base developed in the study states by the Health Care Financing Agency. Analyses studied the association between aspects of the staff and physical environment and resident agitation levels, controlling for resident cognitive and functional status. SETTING: Special Care Units in nursing homes in Kansas, Maine, Mississippi, and South Dakota. PARTICIPANTS: All residents and staff of the participating units. MAIN OUTCOME MEASURES: Eight specific agitated behaviors and two indexes of resident agitation were measured by direct observation by research assistants on three to four data collection walk-throughs in each of the study facilities. RESULTS: The most common agitated behaviors noted were repetitive mannerisms (4.5% of resident observations) and non-loud verbal excess (3.8%). Wandering, which frequently reflects agitation, was noted in 6.5% of resident observations. The proportion of residents exhibiting an agitated behavior varied from none in some units to 38% in one unit. Independent correlates of low unit agitation levels included favorable scores on measures of the physical environment and of staff treatment activities, low rates of physical restraint use, a high proportion of residents in bed during the day, small unit size, low levels of resident functional dependency, and fewer numbers of comorbid conditions. CONCLUSIONS: While the prevalence of agitation tends to increase as Alzheimer's disease progresses, modifiable treatment factors appear to have a strong influence on the prevalence of agitation. Both physical design and staff treatment appear to influence agitation rates, as do some measures consistent with a low stimulus approach to Alzheimer's care.

Activities of Daily Living↗

PubMed1998

The association of non-insulin-dependent diabetes mellitus with perceived quality of life in a biethnic population: the San Luis Valley Diabetes Study.

OBJECTIVES: This study evaluated the association between quality of life and non-insulin-dependent diabetes mellitus (NIDDM) status, and whether this association differs between Hispanics and non-Hispanic Whites. METHODS: Between 1986 and 1989, cross-sectional data on perceived quality of life (PQOL) were collected from 223 persons with NIDDM and 753 non-diabetic subjects. RESULTS: After adjustment, persons with NIDDM rated their PQOL significantly lower than did control subjects. The relationship of diabetes and PQOL did not differ by ethnicity. The number of complications of diabetes was not associated with lower PQOL scores. CONCLUSIONS: Control and treatment strategies should reflect an understanding of the impact that diabetes has on social functioning, leisure activities, and physical and mental health.

Adaptation, Psychological↗

PubMed1997

The structure of problem and positive behavior among American Indian adolescents: gender and community differences.

Using Problem-Behavior Theory as framework, the latent structure of problem and positive behaviors was examined within a sample of 1,894 American Indian adolescents. Support was found for a two-factor second-order structure in which problem behaviors (antisocial behavior, alcohol use, drug use, and risky sexual behavior) and positive behaviors (school success, cultural activities, competencies, and community-mindedness) represented two relatively uncorrelated aspects of behavior. Hierarchical multiple regressions demonstrated that the positive behaviors construct contributed significant incremental construct validity in the statistical prediction of psychosocial outcomes, over and above the problem behaviors. In addition, the fit of the structure was examined across gender and the four participating communities. The importance of the inclusion of positive behaviors is discussed from the standpoint of both prevention/promotion activities and the communities' perceptions. Further recommendations are made for deeper understandings of community concerns and strengths in conducting preventive/promotive research efforts.

Adolescent↗

PubMed1996

Alcohol use among American Indian adolescents: the role of culture in pathological drinking.

Over the last 20 years, the field of substance use among American Indian adolescents has come to be dominated by survey approaches that are unable to answer important questions about how the use of alcohol and drugs is conceptualized and meaningfully integrated in the lives of Indian teens. Without a model of adolescent alcohol use that incorporates culture, the field misapprehends the social and cultural grounding of both normal and pathological drinking, and cannot accurately differentiate between normal and pathological drinking. Traditionally, the field has relied upon either a biological model or a distress model, thus locating pathology in the biochemistry of ethanol ingestion or in psychopathological distress. However, findings from an ethnographic investigation of alcohol use among American Indian adolescents suggest that the criteria for distinguishing pathological drinking lie, instead, in the developmental and gender-specific expectations that derive from cultural values. Specifically, at a Northern Plains site, teen drinking is judged by whether drinking has begun to interfere with developmental tasks relating to the cultural values of courage, modesty, humor, generosity and family honor. We conclude with suggestions for clinicians and researchers that offer the potential to facilitate the incorporation of culture into research and practice in the field of American Indian adolescent alcohol use.

Adolescent↗

PubMed1996

Factors associated with the receipt of alcohol treatment services among American Indian adolescents.

OBJECTIVE: This study examines factors potentially associated with the receipt of alcohol treatment services among a large sample of American Indian adolescents. METHOD: Data for this study were drawn from the Voices of Indian Teens project, a 5-year, longitudinal project involving school-based survey data collection at 10 primarily American Indian schools. In November 1992 a total of 2,077 American Indian youths in grades 9 through 12 completed self-report surveys. Of these, 1,681 had a complete set of data for these analyses. Three logistic regression models were developed to predict the probability of (1) receipt of treatment, (2) treatment recommendation, and (3) receipt of treatment among those teenagers who received a treatment recommendation. RESULTS: The probability of an individual receiving treatment was 15 times greater if treatment was recommended. Treatment recommendation mediated the relationship of several measures of psychological distress and alcohol use, abuse, and dependence with actual treatment. CONCLUSIONS: Recommendation for treatment is strongly associated with receiving treatment. Community education about the risks, signs, symptoms, need, and mechanisms for obtaining treatment of alcohol abuse among youths might help alcohol-abusing individuals receive the help they need.

Adolescent↗

PubMed1995

The time course of basic fibroblast growth factor expression in crush-injured skeletal muscles of SJL/J and BALB/c mice.

Staining for basic fibroblast growth factor (bFGF), a potent mitogen, was examined in muscle recovering from a crush injury and compared between two mouse strains with distinctly different capacities for muscle regeneration to determine if bFGF staining and the steps and outcome of repair were related. Immunofluorescence studies on intact and crushed tibialis anterior muscle were carried out at 0, 1, 3, 6, and 12 h postcrush in SJL/J mice, and at 1, 2, 3, 5, 7, and 11 days after injury in both SJL/J and BALB/c mice (n = 2-4). Disrupted fibers showed increased sarcoplasmic staining for bFGF as little as 3-6 h after injury prior to infiltration with intensely fluorescent mononuclear cells (at 12-24 h). Fiber bFGF was maintained in SJL/J muscles for 2 days, but was lower in most damaged fibers of BALB/c muscles at the same time. Surviving stumps of crushed fibers, once sealed, exhibited sarcoplasmic extensions, some of which stained intensely for bFGF. These processes appeared to connect adjacent fiber stumps, and many were noted in association with aligned mononuclear cells (presumptive myoblasts) at the site of new myotube formation. In representative sections there were more bFGF-positive mononuclear cells present in SJL/J than BALB/c muscles. Intense bFGF localization marked newly regenerating myotubes in both SJL/J and BALB/c muscles, and such myotubes were more frequent and larger in SJL/J muscles. More bFGF was present in regenerating muscles of SJL/J compared with BALB/c mice (with respect to damaged myofibers, mononuclear cells, and myotubes) and this correlates with the superior new muscle formation seen in SJL/J mice. These studies support the idea of a positive relation between bFGF in damaged fibers, the bFGF-positive mononuclear cells, and the speed and success of muscle regeneration.

Animals↗

PubMed1995

Predictors of fear of falling in dizzy and nondizzy elderly.

Fear of falling may constitute an independent risk factor for disability, leading older people to unnecessarily restrict their activity. Sixty older adults with chronic dizziness and 66 healthy controls were studied to help clarify the interrelationships among demographic factors, psychological status, physical health, and fear of falling. Chronic dizziness was strongly associated with fear of falling; among dizzy patients, nearly half (47%) expressed fear of falling, in comparison with 3% of controls. In participants with dizziness, 3 factors predicted fear of falling: an activity of daily living score, the revised Symptom Checklist 90 Depression (Derogatis, 1983) score, and stability when standing with feet together. These results support the concept that fear of falling is multiply determined and that psychological factors play a major role in influencing the symptoms and responses in many older patients with dizziness.

Accidental Falls↗

PubMed1995

Validation of the Minimum Data Set Cognitive Performance Scale: agreement with the Mini-Mental State Examination.

BACKGROUND: Almost all nursing homes in the United States are required by the 1987 Omnibus Budget Reconciliation Act to assess each resident's functional, medical, psychosocial, and cognitive status using a standard instrument known as the Minimum Data Set (MDS). We report a validation study to show that the MDS Cognitive Performance Scale (CPS), a cognitive measure generated from 5 MDS items (comatose status, decision making, short-term memory, making self understood, and eating) can be used to detect cognitive impairment as defined by the Mini-Mental State Examination (MMSE). METHODS: Two hundred subjects were randomly recruited from 8 nursing home facilities in North Carolina. Two medical students administered the MMSE, while a geriatric research nurse was responsible for collecting MDS cognitive items, which included the 5 items required for generating CPS scores. Cognitive impairment was defined by MMSE scores adjusted for education. Agreement between the CPS and the MMSE in identifying cognitively impaired subjects was then evaluated. RESULTS: The CPS showed substantial agreement with the MMSE in the identification of cognitive impairment; the sensitivity was .94 (95% confidence interval [CI]: .90, .98), the specificity was .94 (95% CI: .87, .96), and the diagnostic accuracy as measured by the area under the receiver operating characteristics (ROC) curve was .96 (95% CI: .88, 1.0). CONCLUSIONS: The MDS Cognitive Performance Scale, when performed by a trained research nurse using recommended protocols, provides a valid measure of cognitive status in nursing home residents.

Aged↗

PubMed1994

Psychological factors associated with chronic dizziness in patients aged 60 and older.

OBJECTIVE: To identify the prevalence and character of psychological disorders accompanying chronic dizziness in older patients. DESIGN: Case series of patients from a geriatric dizziness clinic, with comparison data from age- and sex-matched healthy community controls. Both cases and controls received screening psychological testing; all cases were evaluated by a clinical psychologist as part of the dizziness clinic evaluation. SETTING: Multidisciplinary Geriatric Dizziness Clinic. PARTICIPANTS: Fifty six consecutive patients with chronic dizziness, evaluated by a multidisciplinary Geriatric Dizziness Clinic, and 68 healthy volunteers whose age and sex distribution matched that of the dizziness clinic patients. MEASUREMENTS: Standardized questionnaire for medical, functional, and demographic data; the anxiety, depression, somatization, and phobic anxiety subscales of the Symptom/Checklist-90 (SCL-90-R); the Tinetti gait and motor screen; a physical therapy evaluation; selected laboratory tests; evaluation by a geriatrician; and a formal evaluation by a clinical psychologist, including a semistructured interview. Psychological diagnoses were assigned based on DSM-III-R criteria. MAIN RESULTS: Of these patients with chronic dizziness, 37.5 percent had a psychological diagnosis causing or contributing to their dizziness problem. Of these, only 3 were felt to have a primary psychological cause of their dizziness, and 18 had secondary psychological diagnoses. Anxiety disorders, depression, and adjustment reactions were the most common diagnoses. On multivariate analysis, factors predicting a psychological diagnosis were a positive response to hyperventilation testing, a high score on the SCL-90 anxiety subscale, and fatigue as a precipitant of dizziness. In addition, dizziness clinic patients scored significantly higher (P < 0.001) on all 4 subscales of the SCL-90 when compared with the healthy elderly, suggesting a greater degree of psychological distress among these elderly with chronic dizziness. CONCLUSIONS: Psychological disorders are rare as primary causes but are common as contributing or modulating factors in older persons with dizziness.

Age Factors↗

PubMed1991

Health status and health care use in persons with inflammatory bowel disease. A national sample.

We randomly surveyed 997 members of the Crohn's and Colitis Foundation of America with inflammatory bowel disease (320 ulcerative colitis and 671 Crohn's disease) in order to: (1) assess their health status, (2) compare members with ulcerative colitis and Crohn's disease, and (3) determine the correlates of health care use. Data collection included variables relating to physical and psychological symptoms, medication use, daily functional status, perceptions of health, and coping styles. The findings indicate that: (1) despite a number of symptoms and complications related to inflammatory bowel disease, the health status of this population is generally good and may be a result of effective coping styles; (2) those with Crohn's disease have more psychosocial difficulties, which appear related to greater symptom severity; (3) both psychosocial and physical health variables are related to number of physician visits, while primarily physical health variables are related to number of hospitalizations and surgeries. Further studies are needed to determine the representativeness of this self-selected sample with others having IBD. In this study, we have provided the basis for developing a more sensitive measure of health status than currently exists, and one which may have implications for future clinical studies.

Adaptation, Psychological↗