Biomedical subjects

C R Roberts

Publications and source records attributed to C R Roberts.

At least 19 recordsLinked to original sources

PubMed2004

What do we mean by the term "inflammation"? A contemporary basic science update for sports medicine.

Most practicing sports medicine clinicians refer to the concept of "inflammation" many times a day when diagnosing and treating acute and overuse injuries. What is meant by this term? Is it a "good" or a "bad" process? The major advances in the understanding of inflammation in recent years are summarised, and some clinical implications of the contemporary model of inflammation are highlighted.

Anti-Inflammatory Agents↗

PubMed2004

Supplementation of a home-based exercise programme with a class-based programme for people with osteoarthritis of the knees: a randomised controlled trial and health economic analysis.

OBJECTIVES: To establish the relative effectiveness and cost of providing a home-based exercise programme versus home-based exercise supplemented with an 8-week class-based exercise programme. DESIGN: The trial was a pragmatic, single-blind randomised clinical trial accompanied by a full economic evaluation. SETTING: Patients were randomly allocated to either home-based exercise or home exercise supplemented with class exercise programmes. PARTICIPANTS: A total of 214 patients, meeting the American College of Rheumatology's classification of knee osteoarthritis, were selected from referrals from the primary and secondary care settings. INTERVENTIONS: Both groups were given a home exercise programme aimed at increasing lower limb strength, and endurance, and improving balance. The supplemented group also attended 8 weeks of twice-weekly knee classes run by a physiotherapist. Classes represented typical knee class provision in the UK. MAIN OUTCOME MEASURES: Assessments of locomotor function, using a timed score of three locomotor activities, walking pain and self-reported disability with the Western Ontario and McMaster's Universities osteoarthritis index (WOMAC) were made. General health, lower limb strength, range of movement and compliance with exercise were also measured. Patients were assessed before and after treatment, and also at 6- and 12-month follow-ups. The economic evaluation looked at health service resource use and assessed cost-effectiveness by relating differential costs to differences in quality-adjusted life-years (QALYs) based on patients' responses to the EuroQol-5 Dimensions. Data were obtained at baseline, 1 month, 6 months and 12 months through face-to-face interviews and, where appropriate, examination of hospital medical records. RESULTS: Patients from the supplemented group demonstrated significantly greater improvement in locomotor function and decrease in pain while walking at all follow-ups. The supplemented group also demonstrated smaller but significant improvements in balance, strength, WOMAC score, and the physical function and pain dimensions of the Short Form-36. However, not all of these improvements were maintained over the 12-month follow-up period. There was no evidence that compliance with the home exercise programme was different or that total costs or mean QALY gains were significantly different between the groups. However, costs were slightly lower and QALY gains slightly higher in the group with the supplementary class-based programme. The economic evaluation suggests that supplemented programmes are likely to be considered cost-effective, although there is uncertainty around this estimate, with approximately 30--35% probability that the intervention would not be cost-effective. CONCLUSIONS: The supplementation of a home-based exercise programme with a class-based exercise programme led to superior improvement in the supplemented group. These differential improvements were still evident at review 12 months after treatment had ceased. The additional cost of the supplemented group was offset by reductions in resource use elsewhere in the system. Compliance with the home exercise programme did not differ between the groups. Based on this evidence, the supplementation of a home-based exercise programme with an 8-week class-based exercise programme can be confidently expected to produce small improvements in locomotor function and clinically important reductions in pain. It is recommended that future research investigates methods of increasing compliance with home exercise programmes and evaluates the impact of these interventions in the primary care setting, where most patients with knee osteoarthritis are managed.

Aged↗

PubMed2001

Cellular activation of MMP-2 (gelatinase A) by MT2-MMP occurs via a TIMP-2-independent pathway.

The role of membrane-type (MT) 2-matrix metalloproteinase (MMP) in the cellular activation of MMP-2 and the tissue inhibitor of matrix metalloproteinase (TIMP) requirements for this process have not been clearly established. To address these issues a TIMP-2-free cell line derived from a Timp2-/- mouse was transfected for stable cell surface expression of hMT2-MMP. Untransfected cells did not activate endogenous or exogenous TIMP-2-free MMP-2 unless both TIMP-2 and concanavalin A (ConA) were added. Transfected cells expressing hMT2-MMP efficiently activated both endogenous and exogenous MMP-2 (within 4 h) via the 68-kDa intermediate in the absence of TIMP-2 and ConA. In contrast, activation of MMP-2 by Timp2-/- cells expressing recombinant hMT1-MMP occurred more slowly (12 h) and required the addition of 0.3-27 nm TIMP-2. Addition of TIMP-2 or TIMP-4 did not enhance MMP-2 activation by MT2-MMP at any concentration tested; furthermore, activation was inhibited by both TIMPs at concentrations >9 nm, consistent with the similar association rate constants (k(on)) calculated for the binding of TIMP-4 and TIMP-2 to MT2-MMP (3.56 x 10(5) m(-1) s(-1) and 6.52 x 10(5) m(-1) s(-1), respectively). MT2-MMP-mediated activation involved cell surface association of the MMP-2 in a hemopexin carboxyl-terminal domain (C domain)-dependent manner: Exogenous MMP-2 hemopexin C domain blocked activation, and cells expressing hMT2-MMP did not bind or activate a truncated form of MMP-2 lacking the hemopexin C domain. These studies demonstrate the existence of an alternative TIMP-2-independent pathway for MMP-2 activation involving MT2-MMP, which may be important in mediating MMP-2 activation in specific tissues or pathologies where MT2-MMP is expressed.

Animals↗

PubMed2001

Palmitoylation of the Rous sarcoma virus transmembrane glycoprotein is required for protein stability and virus infectivity.

The Rous sarcoma virus (RSV) transmembrane (TM) glycoprotein is modified by the addition of palmitic acid. To identify whether conserved cysteines within the hydrophobic anchor region are the site(s) of palmitoylation, and to determine the role of acylation in glycoprotein function, cysteines at residues 164 and 167 of the TM protein were mutated to glycine (C164G, C167G, and C164G/C167G). In CV-1 cells, palmitate was added to env gene products containing single mutations but was absent in the double-mutant Env. Although mutant Pr95 Env precursors were synthesized with wild-type kinetics, the phenotypes of the mutants differed markedly. Env-C164G had properties similar to those of the wild type, while Env-C167G was degraded faster, and Env containing the double mutant C164G/C167G was very rapidly degraded. Degradation occurred after transient plasma membrane expression. The decrease in steady-state surface expression and increased rate of internalization into endosomes and lysosomes paralleled the decrease in palmitoylation observed for the mutants. The phenotypes of mutant viruses were assessed in avian cells in the context of the pATV8R proviral genome. Virus containing the C164G mutation replicated with wild-type kinetics but exhibited reduced peak reverse transcriptase levels. In contrast, viruses containing either the C167G or the C164G/C167G mutation were poorly infectious or noninfectious, respectively. These phenotypes correlated with different degrees of glycoprotein incorporation into virions. Infectious revertants of the double mutant demonstrated the importance of cysteine-167 for efficient plasma membrane expression and Env incorporation. The observation that both cysteines within the membrane-spanning domain are accessible for acylation has implications for the topology of this region, and a model is proposed.

Amino Acid Sequence↗

PubMed2000

Domain interactions in the gelatinase A.TIMP-2.MT1-MMP activation complex. The ectodomain of the 44-kDa form of membrane type-1 matrix metalloproteinase does not modulate gelatinase A activation.

On the cell surface, the 59-kDa membrane type 1-matrix metalloproteinase (MT1-MMP) activates the 72-kDa progelatinase A (MMP-2) after binding the tissue inhibitor of metalloproteinases (TIMP)-2. A 44-kDa remnant of MT1-MMP, with an N terminus at Gly(285), is also present on the cell after autolytic shedding of the catalytic domain from the hemopexin carboxyl (C) domain, but its role in gelatinase A activation is unknown. We investigated intermolecular interactions in the gelatinase A activation complex using recombinant proteins, domains, and peptides, yeast two-hybrid analysis, solid- and solution-phase assays, cell culture, and immunocytochemistry. A strong interaction between the TIMP-2 C domain (Glu(153)-Pro(221)) and the gelatinase A hemopexin C domain (Gly(446)-Cys(660)) was demonstrated by the yeast two-hybrid system. Epitope masking studies showed that the anionic TIMP-2 C tail lost immunoreactivity after binding, indicating that the tail was buried in the complex. Using recombinant MT1-MMP hemopexin C domain (Gly(285)-Cys(508)), no direct role for the 44-kDa form of MT1-MMP in cell surface activation of progelatinase A was found. Exogenous hemopexin C domain of gelatinase A, but not that of MT1-MMP, blocked the cleavage of the 68-kDa gelatinase A activation intermediate to the fully active 66-kDa enzyme by concanavalin A-stimulated cells. The MT1-MMP hemopexin C domain did not form homodimers nor did it bind the gelatinase A hemopexin C domain, the C tail of TIMP-2, or full-length TIMP-2. Hence, the ectodomain of the remnant 44-kDa form of MT1-MMP appears to play little if any role in the activation of gelatinase A favoring the hypothesis that it accumulates on the cell surface as an inactive, stable degradation product.

Animals↗

PubMed2000

Fatalism and risk of adolescent depression.

This research examined fatalism, the belief in external control over life chances, as a risk factor for adolescent depression. Data were analyzed from a large (N = 5,423) sample of adolescents attending middle school in an ethnically diverse community in the southwest. It was hypothesized that adolescents who demonstrated greater fatalism would have a higher risk for depression. Bivariate associations between fatalism and depression were substantial, with an odds ratio (OR) of nearly 25 for depression with impairment and nearly 13 for depression without impairment. Adjustment for the effects of 10 covariates drawn from three domains (status attributes, stressors, and personal/social resources) essentially eliminated the association between fatalism and depression with impairment. However, the OR was still 2.6. The significant association between fatalism and depression without impairment (OR = 2.7) remained after adjustment for covariates. The results provide further support for models of depression which emphasize the role of psychosocial deficits. In this case, we found depression was associated not only with greater fatalism but also greater pessimism, lower self-esteem, more passive coping, and less social support.

Adaptation, Psychological↗

PubMed2000

Ethnocultural differences in sleep complaints among adolescents.

Data from a school survey (N = 5423) were used to examine differences in sleep complaints among adolescents from nine ethnocultural groups. Compared with Anglo youths, Chinese American youths were at significantly lower risk for insomnia, whereas Mexican American youths had an elevated risk, adjusting for the effects of age, gender, and socioeconomic status. Adjusting for the same three covariates, African, Mexican and Central American youths were at elevated risk for hypersomnia. No group was at lower risk for hypersomnia than the Anglos. The results suggest minority status may affect risk for sleep problems but that the direction and the magnitude of the effects vary depending on the outcome examined, severity of the problem, and the ethnic group studied. Given the paucity of data on culture and risk for disturbed sleep among adolescents, more research is needed on the role of ethnocultural background on sleep.

Adolescent↗

PubMed1999

Gene transfer of cytokine inhibitors into human synovial fibroblasts in the SCID mouse model.

OBJECTIVE: To investigate the effects of retrovirus-based gene delivery of inhibitory cytokines and cytokine inhibitors into human synovial fibroblasts in the SCID mouse model of rheumatoid arthritis (RA). METHODS: The MFG vector was used for gene delivery of tumor necrosis factor alpha receptor (TNFalphaR) p55, viral interleukin-10 (IL-10), and murine IL-10 into RA synovial fibroblasts. The effect on invasion of these cells into human articular cartilage and on perichondrocytic cartilage degradation was examined after 60 days of coimplantation into the SCID mouse. RESULTS: TNFalphaR p55 gene transfer showed only a limited effect on inhibition of RA synovial fibroblast invasiveness and cartilage degradation. In contrast, invasion of the RA synovial fibroblasts into the coimplanted cartilage was strongly inhibited by both viral and murine IL-10. Perichondrocytic cartilage degradation was not affected by either form of IL-10. CONCLUSION: The data show that cytokines can be successfully inserted into the genome of human RA synovial fibroblasts using a retroviral vector delivery system, and that the SCID mouse model of human RA is a valuable tool for examining the effects of gene transfer. In addition, inhibition of more than one cytokine pathway may be required to inhibit both synovial- and chondrocyte-mediated cartilage destruction in RA.

Animals↗

PubMed1999

Phlebotomine sand fly (Diptera: Psychodidae) seasonal distribution and infection rates in a defined focus of Leishmania tropica.

A two-year study was conducted of phlebotomine sand fly fauna in a defined focus of Leishmania tropica. A total of 17,947 sand flies representing 10 species were collected from the location. Phlebotomus guggisbergi, a vector of L. tropica in Kenya, was the most prevalent species through the entire period, representing about 80% of the total catch. There was marked seasonal fluctuation in the populations of the three most common species, with highest population levels reached in December and lowest levels reached in July and August. Leishmania-like infections were encountered in 489 P. guggisbergi. No flagellate infections were observed in any other species of sand fly. Although infected P. guggisbergi were collected during each month of the year, the percent parous infected flies was highest (27.5%) during the November through January time period. These data show that the greatest risk of transmission to humans at this focus occurs during December, when the vector is prevalent and infections are common.

Animals↗

PubMed1998

Role of factor V Leiden mutation in patients with angiographically demonstrated coronary artery disease.

The study sought to determine whether coagulation factor V Leiden (FV Leiden) plays a role in the pathogenesis of coronary artery disease and/or myocardial infarction. Association of FV Leiden with venous thromboembolism is well established in the literature, but the role of the mutation in arterial thrombotic events is controversial. Some studies have documented an association between the mutation and myocardial infarction and stroke in juveniles. Few studies have explored its possible contribution to coronary atherosclerosis. We screened FV genotype in 850 predominantly white coronary angiography patients. Coronary artery disease risk factors and history of myocardial infarction were then analyzed by genotype. The FV Leiden mutation occurred in 54 (6.4%) patients. There was one homozygote; a 37-year-old, white male smoker with a history of myocardial infarction. Gene frequencies for white males and females were similar: 0.965 for the normal allele and 0.035 for FV Leiden. Gene frequencies for both genders were in Hardy-Weinberg equilibrium. FV Leiden was not a useful predictor (p=0.23) of the presence of clinically defined atherosclerosis (> or = 50% stenosis) in a logistic regression model adjusting for age, lipoprotein (a), total cholesterol, triglycerides, high density lipoprotein cholesterol, and fibrinogen. In addition, there was no difference in frequency of FV Leiden among those with and without medical histories of myocardial infarction (p=0.51). Allelic frequencies of FV Leiden in this patient group do not differ significantly from those reported for white populations. The FV Leiden mutation in its heterozygous state is not independently associated with coronary artery disease or myocardial infarction.

Coronary Angiography↗

PubMed1998

Anti-IL-4 treatment prevents dermal collagen deposition in the tight-skin mouse model of scleroderma.

The tight-skin (Tsk/+) mutant mouse, a putative murine model of scleroderma, is characterized primarily by the excessive deposition of collagen and other extracellular matrix molecules in the dermis, and also by a developmentally acquired defect in pulmonary architecture. Passive transfer experiments have suggested an etiologic role for the immune system in Tsk/+ dermal pathology. In addition, CD4+ T lymphocytes have been shown to be required for the excessive accumulation of dermal collagen in these mice. As IL-4, a product of differentiated CD4+ T cells, is capable of regulating the synthesis of various matrix molecules (including type I collagen) by fibroblasts in vitro, we investigated the potential role of IL-4 in mediating Tsk/+ dermal fibrosis. Confirming that Tsk/+ cells are capable of responding to IL-4, we found receptors for this cytokine on Tsk/+ embryonic fibroblasts and a dermal fibroblast cell line derived from these mice. Furthermore, IL-4 receptors on Tsk/+ fibroblasts were functional since IL-4 stimulation in vitro increased type I collagen secretion from these cells. These results demonstrated the potential for IL-4 to be directly involved in the excessive deposition of dermal collagen in Tsk/+ mice. Critical insight into the role played by IL-4 in mediating the dermal phenotype, however, was obtained following the administration of neutralizing anti-lL-4 antibodies to Tsk/+ mice. This treatment prevented the development of dermal fibrosis, leading to normalization of dermal collagen content. Given the requirement for CD4+ T cells in Tsk/+ dermal fibrosis, our results suggest that Th2 cells and/or factors elaborated by this T cell subset may play a key role in regulating dermal collagen content in this strain.

Animals↗

PubMed1998

Ultrastructure and tensile properties of human tracheal cartilage.

The cartilage of the walls of the trachea and bronchi acts to keep these airways open despite intrathoracic pressure differences during breathing that would otherwise collapse them and limit air flow. Changes in biomechanical properties and composition of airway cartilage may contribute to altered lung function in obstructive lung diseases. To investigate the relationship between collagen organization and equilibrium tensile modulus within the structure of airway cartilage, we used scanning electron microscopy (SEM), histochemistry and equilibrium tensile testing to analyze tracheal cartilage from 10 humans aged 17-81 yr. We show that the surfaces of tracheal cartilage matrix are collagen-rich and surround a proteoglycan-rich core. Collagen fibrils in the superficial zones are oriented in the plane of the cartilage surface. In deeper layers of the cartilage, collagen fibrils are oriented less regularly. Equilibrium tensile modulus of 100 microm thick strips of cartilage was measured and was found to decrease with depth; from 13.6 +/- 1.5 MPa for the ablumenal superficial zone to 4.6 +/- 1.7 MPa in the middle zone (means +/- S.D., n = 10, p < 0.001). Stress-strain curves were linear for strains up to 10% with minimal residual strain. This is consistent with a model in which collagen fibres in the outer layers of the cartilage resist tensile forces, and hydrated proteoglycans in the central zone resist compression forces as the cartilage crescent bends.

Adolescent↗

PubMed1998

Suicidal thinking among adolescents with a history of attempted suicide.

OBJECTIVE: To examine the risk of suicidal plans and ideation, depression, and other factors (low self-esteem, loneliness, fatalism, pessimism) among adolescents with a lifetime history of attempted suicide. METHOD: A self-administered questionnaire was used in a school-based survey of five middle schools (grades 6 through 8) enrolling 6,400 students. Usable questionnaires were obtained from 5,423 (85.3%). Data were obtained on a wide range of constructs including recent and lifetime suicide attempts, recent and lifetime suicide plans, recent ideation, symptoms of DSM-IV major depression, self-esteem, pessimism, loneliness, and fatalism. RESULTS: Data on crude prevalence showed thoughts about death, wishing to be dead, thoughts of suicide, and suicide plans were all significantly higher among youths with a history of attempts. Suicidal thinking was related to being more lonely, more fatalistic, and more pessimistic, and to less self-esteem, in addition to depression and a history of attempts. Multivariate analyses revealed the strongest factors associated with current suicidal thinking were history of attempts (odds ratio [OR] = 3.50), depression (OR = 5.34), and recent life stress (OR = 2.64). Compared with youths with none of the factors examined, those with six or more were at extreme risk (OR = 67.87). CONCLUSIONS: The strong association between history of suicide attempts, current ideation, and depression indicates that past suicide attempts occur in the context of other signs of psychosocial dysfunction. Given the paucity of epidemiological data on the natural history of suicidal behaviors among youths, more epidemiological studies of the antecedents and consequences of the range of suicidal behaviors among children and adolescents are needed. Given the high risk of subsequent suicidal behaviors by youths who have attempted but not completed suicide, this constitutes a high-risk population on which future research should focus.

Adolescent↗

PubMed1997

Human IL-1Ra gene transfer into human synovial fibroblasts is chondroprotective.

Rheumatoid arthritis (RA) is characterized by progressive destruction of synovial cartilage. In vitro, degradation of cartilage is stimulated by IL-1, a proinflammatory cytokine, which is released from RA synovial fibroblasts (RA-SF). To determine whether gene therapy using the gene encoding the naturally occurring inhibitor of IL-1, IL-1 receptor antagonist (IL-1Ra) is feasible, IL-1 Ra-transduced RA-SF were coimplanted with normal human cartilage in SCID mice. The IL-1 Ra-transduced RA-SF continued to secrete IL-1Ra over a 60-day period. Cartilage that was coimplanted with RA-SF transduced with a marker gene exhibited progressive, chondrocyte-mediated cartilage degradation, whereas no such degradation was observed in cartilage that was coimplanted with RA-SF transduced with IL-1 Ra. Thus, gene therapy using a retrovirus-based gene delivery system appears to be a feasible approach to effectively modifying the local synovial environment.

Animals↗

PubMed1997

The structural and functional consequences of chronic allergic inflammation of the airways.

Although asthma is generally considered a form of reversible airway obstruction, there is evidence that chronic allergic inflammation can lead to structural changes in the airway and a degree of progressive fixed airway obstruction. More importantly, these structural changes can lead to airway hyper-responsiveness. The structural consequences of chronic allergic inflammation are secondary to cellular proliferation and reorganization of the connective tissue constituents of the airway wall. Smooth muscle proliferation and hypertrophy may increase the potential for smooth muscle shortening against the elastic loads provided by lung parenchymal recoil and airway mucosal folding. Resident airway cells, as well as inflammatory cells, produce mediators, cytokines and growth factors that stimulate production of connective tissue proteins and proteoglycans that cause airway remodelling and altered mechanical function. Thickening of the airway wall internal to the smooth muscle layer can amplify the effect of smooth muscle shortening on airway calibre, and it could also stiffen the airway making it less distensible. Thickening of the airway wall external to the muscle can uncouple the airway from the distending force applied by the lung parenchyma. Early and aggressive anti-inflammatory medication may alter the natural history of asthma by preventing the structural changes that are a consequence of chronic allergic inflammation.

Airway Obstruction↗

PubMed1997

Ethnocultural differences in prevalence of adolescent depression.

Data from an ethnically diverse sample of middle school (Grades 6-8) students (n = 5,423) are analyzed for ethnic differences in major depression. The point prevalence of major depression was 8.4% without and 4.3% with impairment. Data were sufficient to calculate prevalences for nine ethnic groups. Prevalences adjusted for impairment ranged from 1.9% for youths of Chinese descent to 6.6% for those of Mexican decent. African and Mexican American youths had significantly higher crude rates of depression without impairment, but only the latter had significantly higher rates of depression with impairment. Multivariate (logistic regression) analyses, adjusting for the effects of age, gender, and socioeconomic status (SES), yielded significant odds ratios for only one group. Mexican American youths were at elevated risk for both depression without (OR = 1.74, p < .05) and depression with impairment (OR = 1.71, p < .05). There was no significant interaction of ethnicity and SES in relation to depression. Females had higher prevalences of depression with and without impairment, as did youths who reported that their SES was somewhat or much worse off than their peers. The data add to growing evidence that Mexican American youths are at increased risk of depression, and that community intervention efforts should specifically target this high-risk group.

Adolescent↗

PubMed1997

Proteoglycans in granulomatous lung diseases.

In nongranulomatous fibrotic lung conditions, we have recently shown that early collagen synthesis by myofibroblasts occurs in an extracellular matrix rich in the proteoglycan versican. We hypothesized that versican is associated with the process of collagen synthesis resulting from chronic inflammation. In this study, we examined the localization of proteoglycans and collagen in the granulomatous lung conditions, sarcoidosis, extrinsic allergic alveolitis (EAA) and tuberculosis (TB). Tissue from individuals with sarcoidosis (n=6), EAA (n=4) and TB (n=2) was examined for glycosaminoglycans and collagen using histochemistry, and for versican, decorin, biglycan, hyaluronan, type I procollagen and alpha-smooth muscle actin using immunohistochemistry. The results showed that in sarcoidosis, EAA and TB, the rim of connective tissue surrounding granulomas contained glycosaminoglycans and collagen, and that glycosaminoglycan staining corresponded to localization of versican. Versican-rich zones contained myofibroblasts that stained intracellularly for type I procollagen. Hyaluronan was found diffusely throughout the matrix. Decorin was localized intracellularly in the epithelioid cells of granulomas and some myofibroblasts. We conclude that the deposition of versican is specific to the early remodelling process in both granulomatous and nongranulomatous lung diseases. In both forms of lung fibrosis, regardless of the nature of the driving inflammatory process, collagen synthesis takes place in a versican-rich provisional matrix. These results suggest that versican may influence the progression of the repair process following many different types of lung injury.

Adult↗

PubMed1997

Ethnocultural differences in prevalence of adolescent suicidal behaviors.

Data from an ethnically diverse sample of middle school students (grades 6-8; n = 5,423) are analyzed for ethnic differences in suicidal ideation, thoughts about suicide in the past 2 weeks, suicide plans, and suicide attempts. Ideation was examined using a four-item scale and a single item on suicidal thoughts. Ideation was higher among females, older youths, and lower status youths. The same general pattern held for recent suicidal plans and attempts, with the exception of gender, where the trend was for males to report more attempts. Lifetime plans and attempts were higher for females, older youths, and lower status youths. Data were sufficient to compare nine ethnic groups. Multivariate logistic regression analyses, adjusting for the effects of age, gender, and socioeconomic status, yielded significant odds ratios using the Anglo groups as the reference, for suicidal ideation for the Mexican (OR = 1.76, p < .001), Pakistani (OR = 2.0, p < .01), and Vietnamese (OR = 1.48, p < .05) American groups. For thoughts about suicide in the past 2 weeks, only Pakistani and Mixed Ancestry youths had elevated risk. For suicidal plans in the past 2 weeks, Mixed Ancestry youths (OR = 2.02, p < .05) and Pakistani youths (OR = 3.20, p < .01) had elevated risk. For recent attempts, only the Pakistani American youths had elevated risk (OR = 3.19, p < .01). Future research needs to address whether these results hold in other ethnically diverse communities and, if so, what factors contribute to increased risk among some minority youth and not others.

Adolescent↗