Using an interactive framework of society and lifecourse to explain self-rated health in early adulthood

This paper presents an integrated model of the determinants of adult health combining lifecourse factors and contemporary circumstances. Using the 1958 British Birth Cohort, it operationalises lifecourse influences in terms of factors from birth to age 33, which might act through latent, pathway, or cumulative effects. Contemporary circumstances are represented by variables at different levels of social aggregation: macro (socio-economic circumstances); meso (involvement in civil society functions); micro (personal social support); and intersecting (job insecurity and life control). Multiple regression models were fitted, using self-rated health at age 33 as the health outcome. To allow for temporal ordering of events, early life factors were entered first in the final model, followed by later childhood factors and, finally current factors. Self-rated health was predicted by variables representing both early and later stage of the lifecourse and also contemporary societal-level factors. The effects of childhood factors were not removed by including contemporary factors, and conversely, contemporary factors contributed to the prediction of self-rated health over and above lifecourse factors. The factors were not collinear; supporting the notion that each dimension was distinct from the others. Although the model accounted for only 9% of the variance in self-rated health, the general conclusion is that both lifecourse and contemporary circumstances should be considered together in explaining adult health.

Bacterial wall products induce downregulation of vascular endothelial growth factor receptors on endothelial cells via a CD14-dependent mechanism: implications for surgical wound healing

INTRODUCTION

Vascular endothelial growth factor (VEGF) is a potent mitogenic cytokine which has been identified as the principal polypeptide growth factor influencing endothelial cell (EC) migration and proliferation. Ordered progression of these two processes is an absolute prerequisite for initiating and maintaining the proliferative phase of wound healing. The response of ECs to circulating VEGF is determined by, and directly proportional to, the functional expression of VEGF receptors (KDR/Flt-1) on the EC surface membrane. Systemic sepsis and wound contamination due to bacterial infection are associated with significant retardation of the proliferative phase of wound repair. The effects of the Gram-negative bacterial wall components lipopolysaccharide (LPS) and bacterial lipoprotein (BLP) on VEGF receptor function and expression are unknown and may represent an important biological mechanism predisposing to delayed wound healing in the presence of localized or systemic sepsis.

MATERIALS AND METHODS

We designed a series of in vitro experiments investigating this phenomenon and its potential implications for infective wound repair. VEGF receptor density on ECs in the presence of LPS and BLP was assessed using flow cytometry. These parameters were assessed in hypoxic conditions as well as in normoxia. The contribution of CD14 was evaluated using recombinant human (rh) CD14. EC proliferation in response to VEGF was quantified in the presence and absence of LPS and BLP.

RESULTS

Flow cytometric analysis revealed that LPS and BLP have profoundly repressive effects on VEGF receptor density in normoxic and, more pertinently, hypoxic conditions. The observed downregulation of constitutive and inducible VEGF receptor expression on ECs was not due to any directly cytotoxic effect of LPS and BLP on ECs, as measured by cell viability and apoptosis assays. We identified a pivotal role for soluble/serum CD14, a highly specific bacterial wall product receptor, in mediating these effects. The decreased VEGF receptor density on ECs accruing from the presence of bacterial wall products resulted in EC hyporesponsiveness to rhVEGF and significant abolition of VEGF-directed EC proliferation.

CONCLUSION

These findings suggest that the well-recognized relationship between bacterial sepsis and attenuated wound healing may be due, in part, to the directly suppressive effects of bacterial wall components on EC VEGF receptor expression and, consequently, EC proliferation.

Matrix metalloproteinase activity inactivates the CXC chemokine stromal cell-derived factor-1

Chemokines provide directional cues for leukocyte migration and activation that are essential for normal leukocytic trafficking and for host responses during processes such as inflammation, infection, and cancer. Recently we reported that matrix metalloproteinases (MMPs) modulate the activity of the CC chemokine monocyte chemoattractant protein-3 by selective proteolysis to release the N-terminal tetrapeptide. Here we report the N-terminal processing, also at position 4-5, of the CXC chemokines stromal cell-derived factor (SDF)-1alpha and beta by MMP-2 (gelatinase A). Robustness of the MMP family for chemokine cleavage was revealed from identical cleavage site specificity of MMPs 1, 3, 9, 13, and 14 (MT1-MMP) toward SDF-1; selectivity was indicated by absence of cleavage by MMPs 7 and 8. Efficient cleavage of SDF-1alpha by MMP-2 is the result of a strong interaction with the MMP hemopexin C domain at an exosite that overlaps the monocyte chemoattractant protein-3 binding site. The association of SDF-1alpha with different glycosaminoglycans did not inhibit cleavage. MMP cleavage of SDF-1alpha resulted in loss of binding to its cognate receptor CXCR-4. This was reflected in a loss of chemoattractant activity for CD34(+) hematopoietic progenitor stem cells and pre-B cells, and unlike full-length SDF-1alpha, the MMP-cleaved chemokine was unable to block CXCR-4-dependent human immunodeficiency virus-1 infection of CD4(+) cells. These data suggest that MMPs may be important regulatory proteases in attenuating SDF-1 function and point to a deep convergence of two important networks, chemokines and MMPs, to regulate leukocytic activity in vivo.

Predictors of low back pain onset in a prospective British study

OBJECTIVES

This study examined predictors of low back pain onset in a British birth cohort.

METHODS

Univariate and multivariate analyses focused on individuals who experienced onset of low back pain at 32 to 33 years of age (n= 571) and individuals who were pain free (n = 5210). Participants were members of the 1958 British birth cohort.

RESULTS

Incident pain was elevated among those with psychological distress at 23 years of age (adjusted odds ratio [OR] = 2.52, 95% confidence interval [CI] = 1.65, 3.86) and among persistent moderate or heavy smokers (adjusted OR = 1.63, 95% CI = 1.23, 2.17). Significant univariate associations involving other factors (e.g., social class, childhood emotional status, body mass index, job satisfaction) did not persist in multivariate analyses.

CONCLUSIONS

This prospectively studied cohort provides evidence that psychological distress more than doubles later risk of low back pain, with smoking having a modest independent effect. Other prospective studies are needed to confirm these findings before implications for low back pain prevention can be assessed.

Monocyte activation and differentiation augment human endogenous retrovirus expression: implications for inflammatory brain diseases

Human endogenous retroviruses (HERVs) have been implicated as causative agents in diseases characterized by inflammation and macrophage activation, such as multiple sclerosis. Because monocyte activation and differentiation influence retroviral transcription and replication, we investigated the contribution of these processes to the expression of four HERV families (HERV-W, HERV-K, HERV-E, and HERV-H) in human monocytes, and autopsied brain tissue from patients with brain diseases associated with increased macrophage activity. Reverse transcriptase-polymerase chain reaction analysis of primary macrophages and U937 monocytoid cells stimulated with phorbol-12-myristate-13-acetate or lipopolysaccharide revealed three- to ninefold increases in HERV-W, HERV-K, and HERV-H RNA levels. In addition, elevated reverse transcriptase activity and HERV RNA were detectable in supernatants from PMA-stimulated U937 cultures, properties that could be attenuated with the inhibitor of monocyte differentiation threonine-lysine-proline. In contrast, stimulation of monocytes decreased or had no effect on HERV-E expression. Compared with controls, HERV-W and HERV-K expression was increased in brain tissue from patients with multiple sclerosis or human immunodeficiency virus infection or AIDS, with concomitant elevated tumor necrosis factor-alpha levels. Similarly, elevated HERV-W levels were detected in patients with Alzheimer's dementia only when tumor necrosis factor-alpha expression was also evident (2 of 6 cases). The detection of several HERVs in inflammatory brain diseases and the capacity to augment HERV expression in monocytes with compounds that influence cellular activity suggest that increased expression of these viruses is a consequence of increased immune activity rather than causative of distinct diseases.

A case for a neonatal, low-dose BCG vaccination trial

The rational design of a successful vaccination strategy against tuberculosis requires certain kinds of information and must take account of several considerations: (i) the nature of the immune response that protects the large majority of individuals infected by Mycobacterium tuberculosis, designated as healthy contacts, must be defined and distinguished from that in tuberculosis patients, whose immune system must have failed; (ii) the vaccination strategy must incorporate a way of priming the immune system to guarantee in all individuals this protective response, normally generated in healthy contacts, upon natural infection by M. tuberculosis; (iii) the strategy must incorporate a mechanism for ensuring that the effectiveness of this priming is not abrogated by exposure to environmental mycobacteria; and (iv) the strategy must take account of the fact that the vaccinated population is genetically heterogeneous, and that individuals will therefore respond variably to most standard vaccination protocols. We describe a tentative proposal for how these interrelated problems might be solved and discuss predictions of this tentative vaccination strategy. Critical testing of the neonatal, low-dose BCG vaccination strategy can only be achieved by a field trial and we outline the considerations underlying this proposal.

Family social class, maternal body mass index, childhood body mass index, and age at menarche as predictors of adult obesity

BACKGROUND

Obesity is an increasingly prevalent nutritional disorder throughout the world and is a risk factor for many chronic diseases. The prevalence of obesity increases with age.

OBJECTIVE

The objective was to evaluate the associations between BMI at 31 y of age and family social class during early childhood, maternal body mass index (BMI) before pregnancy, BMI at birth and at 1 and 14 y of age, and age at menarche.

DESIGN

This was a longitudinal study of the northern Finland birth cohort for 1966. Subjects were measured at birth and at 1, 14, and 31 y of age. The analysis was restricted to individuals for whom BMI data were available for all measurement points (n = 2876 males and 3404 females).

RESULTS

The mean BMI at birth was highest in offspring from the highest social classes, but BMI was inversely related to social class at 1 y. BMI, the waist-to-hip ratio, and the proportion of obese subjects were inversely related to social class at 31 y. The heavier the mother, the heavier the offspring from birth to 31 y. The paired analyses between maternal BMI and daughter's BMI at 31 y showed no significant difference in BMI after adjustment for the age difference. BMI at 14 y was the most important predictor of BMI at 31 y. Early menarche in females was associated with a higher BMI at 14 and 31 y.

CONCLUSIONS

Differences in BMI by social class are formed at least partly during early childhood. Low social class of the child's family, a high maternal BMI before pregnancy, a high BMI during adolescence, and early menarche are predictors of obesity in adulthood.

Encephalopathy with staphylococcal endocarditis: multiple neuropathological findings

BACKGROUND

Infective endocarditis is associated with serious neurological sequelae.

OBJECTIVE

Here, we report a patient with Staphylococcus aureus endocarditis, secondary to congenital heart disease, with subacute onset of multiple neurological complications.

RESULTS

Despite prompt antibiotic treatment with rapid sterilization of blood cultures, the patient died with brain herniation within 96 hours of admission. Neuropathological examination showed intraparenchymal hemorrhages, mycotic aneurysms, micro-abscesses and septic arteritis with accompanying infarction. Immunocytochemical studies revealed enhanced CD45 and GFAP immunoreactivity, together with adenosine A1 receptor detection on macrophages and microglia.

CONCLUSIONS

Infective endocarditis is associated with multiple neuropathological lesions, which may contribute to its poor clinical outcome and activation of cells of monocyte-microglial lineage throughout the brain.

Neurocognitive symptoms and impairment in an HIV community clinic

BACKGROUND

Neurocognitive impairment is a frequent complication of HIV infection and heralds a poor survival prognosis. With the availability of highly active antiretroviral therapy (HAART), survival times for HIV-infected patients have markedly increased although the effects of HAART on the prevalence of neurocognitive impairment remain uncertain.

OBJECTIVE

To determine the relationship between self-reported neurocognitive symptoms and neuropsychological (NP) performance together with the impact of HAART among HIV-infected patients.

METHODS

A cross-sectional study was performed in which patients without previously documented neurocognitive impairment attending an HIV community clinic were questioned about neurocognitive symptoms and a NP test battery was administered.

RESULTS

Of the eighty-three patients examined, neurocognitive symptoms were reported by 34% of patients and were associated with a shorter duration of HAART and higher viral loads. Patients reporting neurocognitive symptoms were also more likely to exhibit impaired NP performance (p<0.005) with NP impairment being detected in 46% of all patients examined (12% with HIV-associated dementia). Neuropsychological impairment was directly correlated with age (p<0.001), plasma viral load (p<0.005) and inversely correlated with the number of prescribed antiretroviral drugs (p<0.01).

CONCLUSIONS

These results suggest that neurocognitive symptoms are predictive of impaired NP performance and that NP impairment remains a frequent finding among older patients with higher viral loads. An increased number of antiretroviral drugs may be neuroprotective.

Xenoinfection of nonhuman primates by feline immunodeficiency virus

New viral infections in humans usually result from viruses that have been transmitted from other species as zoonoses. For example, it is accepted widely that human immunodeficiency virus (HIV) is the result of the propagation and adaptation of a simian immunodeficiency virus (SIV) from nonhuman primates to man [1]. Previously, we reported productive infection of primary human cells in vitro by feline immunodeficiency virus (FIV) [2], a lentivirus that causes an immunodeficiency syndrome in cats similar to HIV in humans [3]. The present study extends these findings by demonstrating that cynomolgus macaques (Macaca fasicularis) infected with FIV exhibited clinical signs, including depletion of CD4+ cells and weight loss, that are consistent with FIV infection. The development of an antibody response to FIV gag-encoded proteins and detection of virus-specific sequences in sera, blood-derived cells, and necropsied tissue accompanied these changes. Moreover, the reactivation of FIV replication from latently infected cells was observed after stimulation in vitro with phorbol esters and in vivo with tetanus toxoid. The proposed use of lentiviruses in human gene therapy [4, 5] and of nonhuman cells and organs in xenotransplantation [6] has raised concerns about zoonoses as potential sources of new human pathogens. Therefore, the study of FIV infection of primate cells may provide insight into the principles underlying retroviral xenoinfections.

Genetic susceptibility to MS: a second stage analysis in Canadian MS families

Four published genome screens have identified a number of markers with increased sharing in multiple sclerosis (MS) families, although none has reached statistical significance. One hundred and five markers previously identified as showing increased sharing in Canadian, British, Finnish, and American genome screens were genotyped in 219 sibling pairs ascertained from the database of the Canadian Collaborative Project on Genetic Susceptibility to MS (CCPGSMS). No markers examined met criteria for significant linkage. Markers located at 5p14 and 17q22 were analyzed in a total of 333 sibling pairs and attained mlod scores of 2.27 and 1.14, respectively. The known HLA Class II DRB1 association with MS was confirmed (P<0.0001). Significant transmission disequilibrium was also observed for D17S789 at 17q22 (P=0.0015). This study highlights the difficulty of searching for genes with only mild-to-moderate effects on susceptibility, although large effects of specific loci may still be present in individual families. Future progress in the genetics of this complex trait may be helped by (1) focussing on more ethnically homogeneous samples, (2) using an increased number of MS families, and (3) using transmission disequilibrium analysis in candidate regions rather than the affected relative pair linkage analysis.

Metalloproteinases in biology and pathology of the nervous system

Matrix metalloproteinases (MMPs) and ADAMs (a disintegrin and metalloproteinase) are part of a larger family of structurally related zinc-dependent metalloproteinases called metzincins. Structurally, MMPs are divided in three domains: an amino-terminal propeptide region, an amino-terminal catalytic domain, and a carboxy-terminal domain that is involved in substrate binding. ADAMs have a prodomain, a metalloprotease region, a disintegrin domain for adhesion, a cysteine-rich region, epidermal-growth-factor repeats, a transmembrane module and a cytoplasmic tail. The activity of MMPs is tightly regulated in several ways: at the level of transcription, by post-translational modifications such as proteolysis, and through the action of endogenous tissue inhibitors of metalloproteinases. The regulation of ADAMs is less well understood, although there is some evidence that the same three levels of regulation might control ADAM activity. MMPs and ADAMs have been implicated in neuroinflammation and multiple sclerosis (MS), in the pathogenesis of malignant gliomas, and in other neurological conditions such as stroke, viral infections and Alzheimer's disease. In the case of ADAMs, their role in these pathological states has begun to be explored, but the available literature is still in its infancy. Although the detrimental roles of metalloproteinases are well documented, some of their functions in the central nervous system (CNS) might be beneficial. For example, some metalloproteinases are expressed in the CNS during development, pointing to a possible role in brain maturation. Similarly, metalloproteinases have been implicated in myelinogenesis and axon growth. Furthermore, metalloproteinases are upregulated after injury to the CNS, indicating a possible relevance to tissue repair. Several challenges remain in the study of metalloproteinases and their role in brain function. It will be necessary to understand the balance between the beneficial and detrimental roles of MMPs to determine whether they can be used as targets for therapeutic intervention. It will also be important to identify the physiological substrates of the different metalloproteinases, and to develop selective antagonists against the various members of the metalloproteinase families; the lack of such tools constitutes one of the main limitations to the growth of the field at present.

Matrix metalloproteinases (MMPs) have been implicated in several diseases of the nervous system. Here we review the evidence that supports this idea and discuss the possible mechanisms of MMP action. We then consider some of the beneficial functions of MMPs during neural development and speculate on their roles in repair after brain injury. We also introduce a family of proteins known as ADAMs (a disintegrin and metalloproteinase), as some of the properties previously ascribed to MMPs are possibly the result of ADAM activity.

Proinflammatory effects of bacterial lipoprotein on human neutrophil activation status, function and cytotoxic potential in vitro

Bacterial lipoprotein (BLP) is the most abundant protein in gram-negative bacterial cell walls, heavily outweighing lipopolysaccharide (LPS). Herein we present findings demonstrating the potent in vitro effects of BLP on neutrophil (PMN) activation status, function, and capacity to transmigrate an endothelial monolayer. PMNs are the principal effectors of the initial host response to injury or infection and constitute a significant threat to invading bacterial pathogens. The systemic inflammatory response syndrome (SIRS) is characterised by significant host tissue injury mediated, in part, by uncontrolled regulation of PMN cytotoxic activity. We found that BLP-activated human PMN as evidenced by increased CD11b/CD18 (Mac-1) expression. Up-regulation of PMN Mac-1 in response to BLP occurred independently of membrane-bound CD14 (mCD14). A similar up-regulation of intercellular adhesion molecule-1 (ICAM-1) on endothelial cells was observed whilst E-Selectin expression was unaffected. PMN transmigration across a human umbilical vein endothelial cell (HUVEC) monolayer was markedly increased after treating either PMN's or HUVEC independently with BLP. This increased transmigration did not occur as a result of any direct effect of BLP on HUVEC monolayer permeability, assessed objectively using the passage of FITC-labeled Dextran-70. BLP primed PMN for enhanced respiratory burst and superoxide anion production in response to PMA, but did not influence phagocytosis of opsonized Escherichia coli. BLP far exceeds LPS as a gram-negative bacterial wall component, these findings therefore implicate BLP as an additional putative mediator of SIRS arising from gram-negative infection.

Adenosine A2A receptor activation reduces proinflammatory events and decreases cell death following intracerebral hemorrhage

The ubiquitous neuromodulator adenosine inhibits the production of several proinflammatory cytokines through activation of specific cell-surface adenosine receptors. We demonstrated recently that antisense oligonucleotides to tumor necrosis factor-alpha (TNF-alpha) are neuroprotective in a rat model of intracerebral hemorrhage. Therefore, we hypothesized that activation of adenosine receptors would provide protection against intracerebral hemorrhage-induced TNF-alpha production and inflammatory events. In vitro experiments showed that adenosine A1, A2A, and A3 receptor subtypes were present on U937 cells, and activation of these subtypes inhibited TNF-alpha production with a rank order of A2A > > A1 > A3. Prolonged treatment of U937 cells with the A2A receptor agonist 2-p-(carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine hydrochloride (CGS 21680) desensitized adenosine A2A, A1, and A3 receptors. CGS 21680 administration directly into the striatum immediately prior to the induction of intracerebral hemorrhage inhibited TNF-alpha mRNA and, 24 hours following induction, reduced parenchymal neutrophil infiltration (p < 0.001) and TUNEL-positive cells (p < 0.002) within and bordering the hematoma. These results suggest that pharmacological strategies targeting A2A receptors may provide effective inhibition of acute neurotoxic proinflammatory events that occur following intracerebral hemorrhage.

Self-rated health and limiting longstanding illness: inter-relationships with morbidity in early adulthood

BACKGROUND

Self-rated health and limiting longstanding illness are both widely used global measures of health, but understanding is poor of their meaning and validity at younger ages.

METHODS

We examined the association between self-rated health and limiting longstanding illness and specific health problems at two ages (23 and 33 years), and assessed change over the 10-year period for each health measure relative to another. Longitudinal data were taken from the nationally representative British birth cohort for which health measures were obtained at ages 23 and 33.

RESULTS

Self-rated health and limiting longstanding illness were strongly associated with each other as well as with specific health problems, particularly with serious conditions (e.g. epilepsy, cancer, diabetes) and more weakly with less serious conditions (e.g. eczema and hay fever). Rating of overall health and limiting longstanding illness was highly stable during the 10-year period with most, but not all, health change reflecting a deterioration in health status. Deterioration in limiting illness corresponded to an even greater health decline in specific conditions.

CONCLUSIONS

Self-rated health and limiting longstanding illness are valid health measures appropriate for use in general health surveys.

Psychological distress and work and home roles: a focus on socio-economic differences in distress

BACKGROUND

Home and work factors have been linked to psychological status, but less is known about their contribution to social inequalities in psychological status. We examine whether social inequalities in psychological distress can be explained by work-home factors and whether the impact of these potential explanatory factors is similar for men and women.

METHODS

Data are from the 1958 British birth cohort study. We sought to explain social class differences in psychological distress at age 33. Explanatory factors were classified as work-home roles: i.e. employment, marital status, domestic responsibility, children and elderly care; and work-home characteristics: i.e. job-strain, insecurity, unsocial working hours, youngest child's age, number of children and level of involvement in childcare.

RESULTS

A social gradient in psychological distress was found: odds ratios for classes IV and V v. I and II were 2.65 (men) and 3.02 (women). Work factors had consistently stronger associations with psychological distress and with social class among men than women. Work factors had a greater impact on class differences in psychological distress in men. Associations for home roles and characteristics were less consistent and their combined effect on class differences in distress was negligible for both sexes.

CONCLUSION

Explanations for the social gradient differ for men and women. Work may be more important for men than women, but the impact of home factors was not strong during the early adulthood of this cohort.

Diminished adenosine A1 receptor expression on macrophages in brain and blood of patients with multiple sclerosis

The nucleoside adenosine has been shown to control the production of proinflammatory molecules through its actions on cell surface purine receptors. Previously, we have reported that the adenosine A1 receptor (A1AR) regulates tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) expression and exhibits diminished function in patients with multiple sclerosis (MS; Mayne et al., Ann Neurol 1999;45:633-639). In the present study, A1AR expression in both brain and peripheral blood mononuclear cells (PBMC) from MS and control groups was characterized by fluorescence-activated cell sorting (FACS), reverse transcriptase-polymerase chain reaction (RT-PCR), and immunohistochemical analyses. FACS analyses of PBMC revealed that A1AR expression was chiefly detectable on CD14-positive cells and was reduced by 53.1% (p < 0.01) in MS patients compared to controls. A1AR mRNA levels were reduced by 43.1% (p < 0.001) in the brains of MS patients compared to patients with other neurological diseases and controls. A1AR protein expression in brain was detected primarily in CD45-positive glial cells and was markedly diminished in MS patients. The analysis of A1AR transcripts in the brain revealed that the A1AR-beta transcript was diminished (49.2%) in MS patients compared to controls (p < 0.002). These results indicate that the A1AR, expressed principally on cells of monocyte/macrophage lineage in both brain and blood, is selectively diminished in MS patients. Reduction of the A1AR-beta transcript in MS patients suggests that dysregulated splicing may influence A1AR protein levels, potentially leading to increased macrophage activation and central nervous system inflammation.

Human immunodeficiency virus type 1 clade A and D neurotropism: molecular evolution, recombination, and coreceptor use

Human immunodeficiency virus type 1 (HIV-1) non-B clade viral infections of the brain have not been studied to date. Among nine AIDS patients from Nairobi, Kenya, infected with HIV-1 A (N = 5) or D (N = 4) clade strains, brain-derived HIV-1 env sequences displayed greater evolutionary distance than B clade brain-derived viruses (P < 0.001). Similarly, molecular diversity between matched brain and spleen env clones was clade-dependent and concentrated in the hypervariable V4 region (P < 0.001), with phylogenetic clustering of sequences derived from the same organ. Brain-derived A and D clade sequences displayed significantly lower ratios of nonsynonymous/synonymous substitution rates (d(N)/d(S)) compared to matched spleen-derived clones and brain-derived B clade viruses. Interclade recombination events were infrequently observed among the present env sequences. A chimeric virus containing the C2V3 region from an A clade brain-derived sequence preferentially used CD4 and CCR5 for infection. These findings demonstrate that differences in molecular diversity in brain-derived sequences were dependent on the individual clade and domain within the env gene, but both B and non-B clade brain-derived viruses exhibit a preference for CCR5 as a coreceptor.

HIV-1 reverse transcriptase sequence in plasma and cerebrospinal fluid of patients with AIDS dementia complex treated with Abacavir

OBJECTIVE

To assess HIV-1 RNA levels and the relationship between HIV-1 reverse transcriptase (RT) genotype from plasma and cerebrospinal fluid (CSF) during treatment with abacavir (Ziagen, ABC) or placebo in combination with stable background therapy (SBG) in subjects with AIDS dementia complex (ADC) (study CNA3001).

DESIGN

One-hundred and five HIV-1 infected adults with ADC were randomized to receive either ABC (600 mg twice daily) or ABC-matched placebo (twice daily) in addition to SBG for 12 weeks.

METHODS

Plasma and CSF were collected for population sequencing at baseline and week 12 (CSF optional). Sequences were analyzed for mutations associated with resistance to nucleoside reverse transcriptase inhibitors (NRTI).

RESULTS

Sixty out of sixty-seven subjects with baseline plasma HIV-RT sequence data harbored virus with > or = 1 NRTI-associated mutations; 50 out of 67 had the M184V mutation. At week 12, more subjects in the ABC group had plasma HIV-1 RNA < or = 400 copies/ml than the SBG group (46% versus 13%, P = 0.002). Non-response to ABC was associated with multiple baseline zidovudine (ZDV)/stavudine (d4T)-associated mutations. Baseline RT mutation patterns differed in 14 out of 21 (67%) paired samples from plasma and CSF. Four subjects experienced > 1 log10 copies/ml reductions in CSF HIV-1 RNA, two in the absence of reductions in plasma HIV-1 RNA and two with undetectable plasma HIV-1 RNA at baseline.

CONCLUSIONS

Substantial decreases in plasma and CSF HIV-1 RNA following addition of ABC were not precluded by baseline HIV-1 NRTI-associated mutations, including the M184V mutation, but non-responders commonly harbored multiple ZDV/d4T-associated mutations. HIV-1 RNA responses and RT genotype appear to be discordant between CSF and plasma in some subjects.

Physical and psychological effects of injury. Data from the 1958 British birth cohort study

BACKGROUND

There is only scant evidence for the long-term health effects of road traffic injuries. We therefore assessed the extent to which motor vehicle driver injuries influence limiting long-standing illness and psychological distress using data from a nationwide study (the 1958 British birth cohort) in early adulthood.

METHODS

Information was obtained on driver injuries occurring between ages 23 and 33 years and limiting illnesses and psychological distress at age 33 years. The risks of injury-related adverse consequences were derived using logistic regression and expressed as odds ratios (ORs) and 95% confidence intervals.

RESULTS

A single injury was associated with limiting illness (OR = 2.01 and 95% CI: 1.38-2.94). The association between a single injury and psychological distress was strong for a recent injury occurring between ages 30 and 33 years (OR = 1.86 and 95% CI: 1.24-2.81), but not for injuries occurring earlier on. The population attributable fraction for limiting illness with one injury was 3.8% (range 1.7-5.3%) and with two or more injuries was 1.0% (range 0.5-1.3%). After controlling for potential confounding factors the corresponding figures were 4.2% (range 2.2-5.6%) and 1.1% (range 0.5-1.3%) respectively.

CONCLUSIONS

Driver injuries are associated with a substantial increase in disability and, also in the short term, with increases in psychological distress. These results highlight the need for identifying effective strategies for the prevention of road traffic injuries as well as more effective approaches for rehabilitation of the injured.

Retroviral diseases of the nervous system: pathogenic host response or viral gene-mediated neurovirulence?

Retroviruses represent an important group of RNA viruses that cause a spectrum of nervous system diseases. Furthermore, newly recognized retroviral infections of the nervous system and some retroviral vectors or proteins used for gene delivery raise potential safety concerns. This article highlights different retroviruses and their causative mechanisms of nervous system disease, or neurovirulence. Specific sequences within retroviral genes might determine the development of neurovirulence. Conversely, neurovirulent retroviruses also activate host immune responses, resulting in a neuropathogenic cascade that is mediated by pro-inflammatory and neurotoxic molecules, ultimately culminating in neuronal death. Thus, retroviral infections of the nervous system illustrate a molecular interplay between distinct infectious agents and pathogenic host responses, which results in neurovirulence.

Seroprevalence of infection with Mycobacterium avium subspecies paratuberculosis, bovine leukemia virus, and bovine viral diarrhea virus in maritime Canada dairy cattle

The purpose of this study was to survey the seroprevalence of infection with the agents of production-limiting diseases in dairy cattle in New Brunswick, Nova Scotia, and Prince Edward Island. In 30 randomly selected herds per province, 30 cattle per herd were randomly selected and tested for antibodies to bovine leukemia virus (BLV) and Mycobacterium avium subspecies paratuberculosis (M. paratuberculosis), while 5 unvaccinated cattle over 6 months of age were tested for antibodies to bovine viral diarrhea virus (BVDV). For BLV, 20.8% (15.8% to 27.0%) of cows were positive, and 70.0% (60.3% to 79.7%) of herds had at least one positive cow. In BLV-positive herds, the average BLV prevalence was 30.9% (24.8% to 37.2%). For M. paratuberculosis, 2.6% (1.8% to 3.9%) of cows were positive, and 16.7% (8.8% to 24.5%) of herds had at least 2 M. paratuberculosis-positive cows. In M. paratuberculosis-positive herds, the average M. paratuberculosis prevalence was 8.5% (6.9% to 10.1%). For BVDV, 46.1% (35.5% to 56.7%) of herds had at least 1 BVDV-positive animal with a titer greater than or equal to 1:64.

Aboriginals with multiple sclerosis: HLA types and predominance of neuromyelitis optica

BACKGROUND

MS is common in people of northern European ethnicity who live in northern geographic areas; however, MS is rarely identified among aboriginal peoples living in the same areas.

OBJECTIVES

To determine the prevalence, clinical features, HLA type, and viral infections associated with MS among aboriginals in Manitoba, Canada.

METHODS

A retrospective study was performed in which the clinical features of all aboriginal patients with MS together with HLA type and human herpesvirus-6, HIV-1, human T-cell lymphotropic virus-1, and endogenous retrovirus associated with MS (MSRV) infections were analyzed and compared with results from nonaboriginal patients with MS.

RESULTS

Seven aboriginals with MS were identified with a period prevalence among aboriginals of 40:100,000. Clinical features included relapsing-remitting (n = 6) or primary progressive (n = 1) phenotypes with aggressive disease courses and frequent involvement of optic nerves and spinal cord (n = 5) compared with nonaboriginal patients. Autopsy of one patient showed necrosis and eosinophil infiltrates in a cervical spinal cord lesion and a demyelinated optic nerve. Analysis of HLA alleles at the DRB1 and DQB1 loci indicated that the HLA types detected were common in aboriginals, but there were no HLA alleles previously associated with the development of MS. Analysis of the copy number of MSRV did not show differences among aboriginals and nonaboriginals with or without MS.

CONCLUSIONS

Aboriginals of Algonkian background are at increased risk for an aggressive type of MS, resembling neuromyelitis optica, which is resistant to conventional MS treatments and occurs independently of HLA alleles previously associated with MS.

HIV-1 Tat neurotoxicity is prevented by matrix metalloproteinase inhibitors

The release of potentially neurotoxic molecules by HIV-infected brain macrophages is accompanied by neuronal injury and death that results in the development of HIV-associated dementia (HAD). Among the potential neurotoxins implicated in the development of HAD is the HIV-1 transactivating protein, Tat. To investigate the mechanism by which Tat causes neurotoxicity, brain-derived Tat sequences from nondemented (Tat-ND) and demented (Tat-HAD) AIDS patients, which differed primarily in the augmenting region of Tat, were expressed in U937 monoblastoid cells and primary human macrophages. Cells expressing Tat-HAD protein exhibited elevated matrix metalloproteinase (MMP)-2 and -7 release and activation, but cells expressing Tat-ND did not exhibit enhanced MMP expression. Conditioned media from Tat-HAD-transfected cells caused significantly greater neuronal death (15.4 +/- 4.3%) than did Tat-ND (4.4 +/- 2.1%) or nontransfected (2.1 +/- 0.8%) cell-derived conditioned media. The neurotoxicity induced by Tat-HAD was inhibited by anti-MMP-2 or -7 antibodies (p < 0.005) but not by antibodies against MMP-9 or Tat. Similarly, scid/nod mice receiving striatal implants of Tat-HAD-transfected cells exhibited greater neurobehavioral abnormalities and neuronal loss (p < 0.005) than did animals receiving Tat-ND or nontransfected cells, which were reduced by treatment with the MMP inhibitor prinomastat (p < 0.005). These findings indicate that Tat causes neuronal death through an indirect mechanism that is Tat sequence dependent and involves the induction of MMPs.

Very low prevalence of bovine immunodeficiency virus infection in western Canadian cattle

Bovine immunodeficiency virus (BIV) is a lentivirus that causes disease in cattle. Despite the large cattle industry in western Canada, the presence of BIV has not been examined to date. Genomic DNA, derived from semen and buffy coat samples, was analyzed by nested polymerase chain reaction (PCR) using specific primers for the gag, pol, and env genes of BIV. Despite utilizing a procedure that detected a minimum of 10 proviral copies, BIV sequences were not amplified in any of 317 buffy coat and 50 semen samples that were obtained from an archive that included 27 cattle breeds, collected from different sources in Alberta (1980-1999). In the 367 DNA samples examined, there was no evidence of BIV infection, suggesting that the prevalence of BIV infection was very low.

Antisense oligodeoxynucleotide inhibition of tumor necrosis factor-alpha expression is neuroprotective after intracerebral hemorrhage

BACKGROUND AND PURPOSE

Tumor necrosis factor-alpha (TNF-alpha) expression is increased in brain after cerebral ischemia, although little is known about its abundance and role in intracerebral hemorrhage (ICH). A TNF-alpha-specific antisense oligodeoxynucleotide (ORF4-PE) was used to study the extent to which TNF-alpha expression influenced neurobehavioral outcomes and brain damage in a collagenase-induced ICH model in rat.

METHODS

Male Sprague-Dawley rats were anesthetized, and ICH was induced by intrastriatal administration of heparin and collagenase. Immediately before or 3 hours after ICH induction, ORF4-PE was administered directly into the site of ICH. TNF-alpha mRNA and protein levels were measured by reverse transcriptase-polymerase chain reaction and immunoblot analyses. Cell death was measured by terminal deoxynucleotidyl transferase-mediated uridine 5'triphosphate-biotin nick end labeling (TUNEL). Neurobehavioral deficits were measured for 4 weeks after ICH.

RESULTS

ICH induction (n=6) elevated TNF-alpha mRNA and protein levels (P:<0.01) at 24 hours after the onset of injury compared with sham controls (n=6). Immunohistochemical labeling indicated that ICH was accompanied by elevated expression of TNF-alpha in neutrophils, macrophages, and microglia. Administration of ORF4-PE (2.0 nmol) directly into striatal parenchyma, 15 minutes before (n=4) or 3 hours after (n=6) ICH, decreased levels of TNF-alpha mRNA (P:<0.001) and protein (P:<0. 01) in the brain tissue surrounding the hematoma compared with animals treated with saline alone (n=6). Mean+/-SEM striatal cell death (cells per high-powered field) was also reduced in animals receiving ORF4-PE (34.1+/-5.0) compared with the saline-treated ICH group (80.3+/-7.50) (P:<0.001). ORF4-PE treatment improved neurobehavioral deficits observed at 24 hours (P:<0.001) after induction of ICH (n=6) compared with the untreated ICH group (n=6). This improvement was maintained at 28 days after hemorrhage induction (P:<0.001).

CONCLUSIONS

These results indicate a pathogenic role for TNF-alpha during ICH and demonstrate that reducing TNF-alpha expression using antisense oligodeoxynucleotides is neuroprotective.

Use of the ultrasonic dissecting scalpel in laparoscopic cholecystectomy

BACKGROUND

We evaluated the use of the ultrasonically activated (harmonic) scalpel (HS) in the performance of laparoscopic cholecystectomy (LC).

METHODS

A total of 282 consecutive patients, 64 of whom had acute cholecystitis at the time of surgery, underwent LC using HS dissection. Indications for surgery included chronic pain (180 cases), episodes of acute cholecystitis (89 cases), pancreatitis (five cases), and jaundice (seven cases). Twenty-seven patients had preoperative endoscopic retrograde cholangiopancreatography (ERCP).

RESULTS

The mean operating time was 29 +/- 9 mins. Eleven procedures were converted to open surgery, (four due to bleeding, six due to unclear anatomy, and one due to an inflammatory mass caused by gangrene/perforation). Complications occurred in 14 patients. They included minor port site infection (four cases), pulmonary atelectasis (three cases), urinary retention (two cases), intraoperative catheterization not routinely performed, bile leak (two cases, both from cystic duct; one of the cystic duct leaks occurred because of dislodgement of the occluding clip, the other may have been due to duct injury from the clip), pulmonary embolus (one case), and myocardial infarction (one case). Neither of the latter complications were fatal. One patient required a postoperative transfusion due to a fall in hematocrit of 3.2 gr/dl.

CONCLUSIONS

LC performed with the HS is feasible and effective. Operating time and blood loss were minimal, and the conversion rate was low (3.9%). There were no bile duct injuries. Use of the HS makes dissection easier, thereby helping to reduce operative time and lower the need for conversion to open surgery.

Dopamine attenuates the chemoattractant effect of interleukin-8: a novel role in the systemic inflammatory response syndrome

Activated neutrophil (PMN) adherence to vascular endothelium comprises a key step for both transendothelial migration and initiation of potentially deleterious release of PMN products. The biogenic amine, dopamine (DA), has been used for several decades in patients to maintain hemodynamic stability. The effect of dopamine on PMN transendothelial migration and adhesion receptor expression and on the endothelial molecules, E-selectin and ICAM-1, was evaluated. PMN were isolated from healthy controls, stimulated with lipopolysaccharide (LPS), and tumor necrosis factor-alpha (TNF-alpha) and treated with dopamine. CD 11b and CD 18 PMN adhesion receptor expression were assessed flow cytometrically. In a separate experiment, the chemoattractant peptide, IL-8, was placed in the lower chamber of transwells, and PMN migration was assessed. Human umbilical vein endothelial cells (HUVEC) were stimulated with LPS/TNF-alpha and incubated with dopamine. ICAM-1 and E-selectin endothelial molecule expression were assessed flow cytometrically. There was a significant increase in transendothelial migration in stimulated PMN compared with normal PMN (40 vs. 14%, P < 0.001). In addition, PMN CD11b/CD18 was significantly upregulated in stimulated PMN compared with normal PMN (252.4/352.4 vs. 76.7/139.4, P < 0.001) as were endothelial E-selectin/ICAM-1 expression compared with normal EC (8.1/9 vs. 3.9/3.8, P < 0.05). After treatment with dopamine, PMN transmigration was significantly decreased compared with stimulated PMN (8% vs. 40%, P < 0.001). Furthermore, dopamine also attenuated PMN CD11b/CD18 and the endothelial molecules E-selectin and ICAM-1 compared with stimulated PMN/EC that were not treated dopamine (174/240 vs. 252/352, P < 0.05 and 4/4.4 vs. 8.1/9, P < 0.05. respectively). The chemoattractant effect of IL-8 was also attenuated. These results identify for the first time that dopamine attenuates the initial interaction between PMN and the endothelium, and consequently, modulates PMN exudation. Thus, biogenic amines, including dopamine, may function as anti-inflammatory cytokines.

Lentivirus infection in the brain induces matrix metalloproteinase expression: role of envelope diversity

Infection of the brain by lentiviruses, including human immunodeficiency virus (HIV) and feline immunodeficiency virus (FIV), causes inflammation and results in neurodegeneration. Molecular diversity within the lentivirus envelope gene has been implicated in the regulation of cell tropism and the host response to infection. Here, we examine the hypothesis that envelope sequence diversity modulates the expression of host molecules implicated in lentivirus-induced brain disease, including matrix metalloproteinases (MMP) and related transcription factors. Infection of primary macrophages by chimeric HIV clones containing brain-derived envelope fragments from patients with HIV-associated dementia (HAD) or nondemented AIDS patients (HIV-ND) showed that MMP-2 and -9 levels in conditioned media were significantly higher for the HAD clones. Similarly, STAT-1 and JAK-1 levels were higher in macrophages infected by HAD clones. Infections of primary feline macrophages by the neurovirulent FIV strain (V(1)CSF), the less neurovirulent strain (Petaluma), and a chimera containing the V(1)CSF envelope in a Petaluma background (FIV-Ch) revealed that MMP-2 and -9 levels were significantly higher in conditioned media from V(1)CSF- and FIV-Ch-infected macrophages, which was associated with increased intracellular STAT-1 and JAK-1 levels. The STAT-1 inhibitor fludarabine significantly reduced MMP-2 expression, but not MMP-9 expression, in FIV-infected macrophages. Analysis of MMP mRNA and protein levels in brain samples from HIV-infected persons or FIV-infected cats showed that MMP-2 and -9 levels were significantly increased in lentivirus-infected brains compared to those of uninfected controls. Elevated MMP expression was accompanied by significant increases in STAT-1 and JAK-1 mRNA and protein levels in the same brain samples. The present findings indicate that two lentiviruses, HIV and FIV, have common mechanisms of MMP-2 and -9 induction, which is modulated in part by envelope sequence diversity and the STAT-1/JAK-1 signaling pathway.

Nutritional and other influences in childhood as predictors of adult obesity

It has been proposed that there are critical periods during childhood that influence the development of obesity, including gestation and early infancy, the period of adiposity rebound that occurs between ages 5 and 7 years, and adolescence. Despite an extensive literature, there is to date only modest evidence for most of the factors such as nutrition, physical activity and other behavioural factors that are suspected as playing a role in the development of obesity. A recent review of this evidence (Parsons et al. 1999) showed, however, a consistent relationship between socio-economic status (SES) of origin and adult obesity, whereby those from lower SES backgrounds were fatter subsequently in adulthood. This association appeared to apply to both men and women, a finding that contrasts with the trends observed in cross-sectional studies, of an association with SES for women only. There are several potential explanations for the SES of origin-adult obesity relationship. SES of origin may be confounded by parental body size; studies to date provide insufficient evidence of an independent association with SES after allowing for parental body size. Alternatively, environment in early life (for which SES of origin is a proxy measure) may have a long-term impact on obesity later in adulthood, through one or more of several processes. Three major potential explanations can be identified: (1) nutrition in infancy and childhood, either over- or undenutrition, followed subsequently by overnutrition; (2) psychological factors, possibly involving emotional deprivation in childhood; (3) cultural or social norms regarding dietary restraint and attitudes to fatness that may be acquired during childhood.

Autopsy study of HIV-1-positive and HIV-1-negative adult medical patients in Nairobi, Kenya

HIV infection has now been consistently identified as the major cause of death in young Africans in both urban and rural areas. In Africa, several studies have defined the clinical presentation of HIV disease but there have only been a limited number of autopsy studies. Because of the scarcity of autopsy data and the possibility of differing type and frequency of opportunistic infections between different geographic locations we set out to study consecutive new adult medical admissions to a tertiary referral hospital in Nairobi and perform autopsies on a sample of HIV-1-positive and HIV-1-negative patients who died in the hospital ward. Basic demographic data were collected on all patients admitted to two acute medical wards over an 11-month period. Final outcome and final clinical diagnoses were recorded at discharge or death. An autopsy examination was requested if the patient died in the ward. Autopsy examination was performed in 75 HIV-1-positive (40 men, 35 women) and 47 HIV-1-negative (28 men, 19 women) adults who died in the hospital. This represented 48.4% of all HIV-1-positive deaths and 33.3% of all HIV-1-negative deaths. Tuberculosis (TB) and bacterial and interstitial bronchopneumonia accounted for 96% of the major pathology in patients found to be HIV-1-positive at autopsy. TB was present in half the HIV-1-positive autopsy patients and was disseminated in over 80% of cases. Meningeal involvement was present in 26% of those with disseminated TB. By contrast, TB was much less common in the HIV-1-negative patients at autopsy in whom bacterial bronchopneumonia and malignancies were the most common pathologies. The type pathology found in the HIV-1-positive autopsy patients was not different than that found in other areas in Africa so far studied.

Back pain and obesity in the 1958 British birth cohort. cause or effect?

An association between obesity and back pain has been observed, but the underlying causal direction is uncertain. We examined the temporal sequence among back pain, BMI, and weight gain using data from the 1958 British birth cohort followed to age 33 (4395 men and 4468 women). Heights and weights were measured at ages 7 and 33, and self-reported at age 23. Back pain was classified as: chronic, incident, early onset but recovered, and never. Those with chronic pain gained more weight between ages 23 and 33 than those with no pain, significantly for women (7.39 kg vs. 6.29 kg). Women who were obese at age 23 years had an elevated risk of subsequent back pain onset (32-33 years) (adjusted OR = 1.78). No significant relationships were found for men. The risk of pain onset among women was evident in relation to BMI at baseline (age 23) and cannot therefore be explained by an effect of back pain on adiposity.

AIDS- and non-AIDS-related PML association with distinct p53 polymorphism

A population-based analysis of progressive multifocal leukoencephalopathy (PML) showed PML frequencies of 5.1% among patients with AIDS and 0.07% among patients with hematologic malignancies, but similar clinical features of PML in both groups. Sequencing of the p53 gene, exon 4, showed heterozygosity (Arg-Pro) at codon 72 in five of six PML patients. These findings indicate that frequencies of non-AIDS- and AIDS-related PML differ markedly but p53 polymorphisms may influence the occurrence of PML in both groups.

Dichotomous or categorical response? Analysing self-rated health and lifetime social class

BACKGROUND

Self-rated health is a commonly used measure of health status, usually having three to five categories. The measure is often collapsed into a dichotomous variable of good versus less than good health. This categorization has not yet been justified.

METHODS

Using data from the 1958 British birth cohort, we examined the relationship between socioeconomic conditions, indicated by occupational class at four ages, and self-rated health. Results obtained for a dichotomous variable using logistic regression were compared with alternative methods for ordered categorical variables including polytomous regression, cumulative odds, continuation ratio and adjacent categories models.

RESULTS AND CONCLUSIONS

Findings concerning the relationship between socioeconomic position and self-rated health yielded by a logistic regression model were confirmed by alternative statistical methods which incorporate the ordered nature of self-rated health. Similarity of results was found regarding size and significance of main effects, type of association and interactive effects.

A prospective study of limiting longstanding illness in early adulthood

BACKGROUND

Chronic illness and disability are of increasing public health importance but little is known about the lifetime influences involved in their onset and progression. We aim to (i) establish whether an individual's rating of limiting illness is stable over a 10-year period from age 23 to 33; (ii) assess the relationship between childhood and adult disability; and (iii) identify lifecourse influences on limiting illness in early adulthood.

METHODS

Data were from the 1958 British birth cohort, including the original birth survey and follow-ups at ages 7, 11, 16, 23 and 33 years. Limiting longstanding illness was the outcome at both ages 23 and 33. Potential predictors included childhood health and physical development, socioeconomic conditions in early life and adulthood, and behavioural factors. We estimated the effect of potential explanatory factors using logistic regression, in both univariate and multivariate analyses, separately for limiting illness at 23 and 33 years.

RESULTS

Prevalence of limiting illness increased from 5.1% (men) and 4.1% (women) at age 23 to 6% for both sexes at age 33. Risk of limiting illness at age 33 was greater for those reporting an illness at age 23 (29.4%, compared with 4.7% of those without illness), though the majority (66%) of 33-year limiting illnesses had no previous record at age 23 or for childhood. Multivariate analysis of limiting illness at age 23 confirmed the high risk for those with childhood disability and also established two further major predictors, namely, injury (adjusted odds ratio [OR] = 1.42, 95% CI: 1.09-1.86) and intermediate socio-emotional status (adjusted OR = 1.73, 95% CI: 1.29-2.31). Additional risks were identified for limiting illness at age 33, including: (i) injury in the preceding 10 years (adjusted OR = 1.55, 95% CI : 1.18-2.04); (ii) body mass index (BMI), for which the relationship was non-linear, with elevated risks for the underweight (adjusted OR = 1.53, 95% CI: 1.03-2.26) and overweight (OR = 1.28, 95% CI: 0.87-1.89); (iii) childhood disadvantage at either or both ages 7 and 11 (adjusted OR = 1.53, 95% CI : 1.07-2.17); and (iv) height at age 7, with a significant non-linear relationship (the adjusted OR for height less than 15th percentile was 1.43 and for height more than the 85th percentile, 1.30).

CONCLUSIONS

Both childhood and adult factors predict limiting illness in early adulthood. Childhood is important because some adult illnesses originate in early life, and also because childhood environment influences the risk of adult limiting illness several years later. Our findings suggest that studies seeking to understand the causes of limiting illness, that currently tend to focus exclusively on contemporary factors, need also to consider the contribution of environment in early life.

Does financial hardship account for elevated psychological distress in lone mothers?

Lone mothers have been shown to have higher levels of psychological distress than married mothers, but it is not clear how this difference arises. Using data from the 1958 British birth cohort followed to age 33, we investigated alternative explanations for the excess distress of lone mothers. Logistic regression models were used to estimate odds ratios for distress (measured using the Malaise Inventory) in lone vs married mothers. Odds ratios were adjusted to assess the contribution of explanatory factors. At age 33, psychological distress was greater among lone than married mothers (OR 2.59, 95% CI 1.97, 3.41). The odds ratio decreased to 1.43 (95% CI 1.02, 2.01) after adjustment for all explanatory factors (prior psychological distress, age of youngest child and number of children in the household, and contemporary measures of financial hardship, employment, and social support). Attenuation of the odds ratio was most marked after taking account of financial hardship. Psychological distress was greater among divorced mothers than never married mothers, though not significantly (OR = 1.70, 95% CI 0.88, 3.28). This difference was not explained by the factors examined, and was not due to the immediate distress associated with a recent divorce. Elevated psychological distress of lone mothers appears to be related to financial hardship, while other explanations, including social support and selection, have a more modest impact. Not all of the elevated psychological distress among lone mothers was accounted for, particularly among divorced lone mothers.

Childhood predictors of adult obesity: a systematic review

OBJECTIVE

To identify factors in childhood which might influence the development of obesity in adulthood.

BACKGROUND

The prevalence of obesity is increasing in the UK and other developed countries, in adults and children. The adverse health consequences of adult obesity are well documented, but are less certain for childhood obesity. An association between fatness in adolescence and undesirable socio-economic consequences, such as lower educational attainment and income, has been observed, particularly for women. Childhood factors implicated in the development of adult obesity therefore have far-reaching implications for costs to the health-services and economy.

SEARCH STRATEGY

In order to identify relevant studies, electronic databases--Medline, Embase, CAB abstracts, Psyclit and Sport Discus-were searched from the start date of the database to Spring 1998. The general search structure for electronic databases was (childhood or synonyms) AND (fatness or synonyms) AND (longitudinal or synonyms). Further studies were identified by citations in retrieved papers and by consultation with experts.

INCLUSION CRITERIA

Longitudinal observational studies of healthy children which included measurement of a risk factor in childhood (<18 y), and outcome measure at least 1 y later. Any measure of fatness, leanness or change in fatness or leanness was accepted. Measures of fat distribution were not included. Only studies with participants from an industrialized country were considered, and those concerning minority or special groups, e.g. Pima Indians or children born preterm, were excluded.

FINDINGS

Risk factors for obesity included parental fatness, social factors, birth weight, timing or rate of maturation, physical activity, dietary factors and other behavioural or psychological factors. Offspring of obese parent(s) were consistently seen to be at increased risk of fatness, although few studies have looked at this relationship over longer periods of childhood and into adulthood. The relative contributions of genes and inherited lifestyle factors to the parent-child fatness association remain largely unknown. No clear relationship is reported between socio-economic status (SES) in early life and childhood fatness. However, a strong consistent relationship is observed between low SES in early life and increased fatness in adulthood. Studies investigating SES were generally large but very few considered confounding by parental fatness. Women who change social class (social mobility) show the prevalence of obesity of the class they join, an association which is not present in men. The influence of other social factors such as family size, number of parents at home and childcare have been little researched. There is good evidence from large and reasonably long-term studies for an apparently clear relationship for increased fatness with higher birth weight, but in studies which attempted to address potential confounding by gestational age, parental fatness, or social group, the relationship was less consistent. The relationship between earlier maturation and greater subsequent fatness was investigated in predominantly smaller, but also a few large studies. Again, this relationship appeared to be consistent, but in general, the studies had not investigated whether there was confounding by other factors, including parental fatness, SES, earlier fatness in childhood, or dietary or activity behaviours. Studies investigating the role of diet or activity were generally small, and included diverse methods of risk factor measurement. There was almost no evidence for an influence of activity in infancy on later fatness, and inconsistent but suggestive evidence for a protective effect of activity in childhood on later fatness. No clear evidence for an effect of infant feeding on later fatness emerged, but follow-up to adulthood was rare, with only one study measuring fatness after 7y. Studies investigating diet in childhood were limited and inconc

Heavy alcohol consumption and marital status: disentangling the relationship in a national study of young adults

AIMS

To investigate why alcohol consumption varies by marital status, assessing (i) differences in heavy consumption prior to changes in marital status (indicating selection) and increases or decreases in heavy consumption associated with changes in marital status (indicating causation), (ii) whether such increases or decreases are transient, and (iii) the possible mediating effect of parental status.

DESIGN

Longitudinal cohort.

SETTING

Great Britain.

PARTICIPANTS

Data from the 23- and 33-year surveys of the 1958 British birth cohort (all born in England, Wales and Scotland, 3-9 March 1958).

MEASUREMENTS

Heavy drinking, defined as more than 35 (men) and 20 (women) units/week; changes between ages 23 and 33 in consumption and marital status.

FINDINGS

The divorced had the highest consumption levels at both ages, the married had the lowest. Selection effects were minimal in both sexes. Overall, heavy drinking declined between ages 23 and 33 (21.4-13.0% in men, 6.4-3.4% in women), but increased among individuals who divorced, compared to the continuously married (adjusted OR = 2.05, 95% CI = 1.49, 2.83 for men; OR = 2.61, 95% CI = 1.67, 4.09 for women), most strikingly for recent divorces (adjusted OR = 4.97, 95% CI = 2.86, 8.57 and OR = 5.25, 95% CI = 2.60, 10.65). High rates of heavy drinking persisted for never married men (19.1%) and women (5.2%).

CONCLUSIONS

The heavy drinking level of divorced young adults was not due to selection. Marital separation was accompanied by increases in heavy drinking, with pronounced short-term effects. Adverse alcohol-related health consequences may occur in the immediate period around divorce. Individuals who never marry appear to have a chronic heavy consumption pattern that may contribute to their increased mortality.

The duration and timing of exposure: effects of socioeconomic environment on adult health

OBJECTIVES

This study investigated timing and duration effects of socioeconomic status (SES) on self-rated health at 33 years of age and established whether health risks are modified by changing SES and whether cumulative SES operates through education.

METHODS

Data were from the 1958 British birth cohort. Occupational class at birth and at 16, 23, and 33 years of age was used to generate a lifetime SES score.

RESULTS

At 33 years of age, 12% of men and women reported poor health. SES at birth and at 16, 23, and 33 years of age was significantly associated with poor health: all ages except 16 years in men made an additional contribution to the prediction of poor health. No large differences in effect sizes emerged, suggesting that timing was not a major factor. Odds of poor health increased by 15% (men) and 18% (women) with a 1-unit increase in the lifetime SES score. Strong effects of lifetime SES persisted after adjustment for education level.

CONCLUSIONS

SES from birth to 33 years of age had a cumulative effect on poor health in early adulthood. This highlights the importance of duration of exposure to socioeconomic conditions for adult health.

Social support at age 33: the influence of gender, employment status and social class

This paper investigates the conceptualisation and operationalisation of social support and it's relationship to gender, employment status and social class. Clarification of these relationships is sought in order to better understand associations between social support and health. We used data from the 33-year survey of the 1958 British birth cohort study. Individual items and subscales of practical and emotional support were examined. In general, men had lower support than women and social classes IV and V had lower support than classes I and II. Emotional support, either from personal (for example, from friends or family), or combined with organisational sources of support (such as from a church or a financial institution), showed consistent gender and social class patterns. This suggests that emotional support is a robust concept across socio-demographic groups. Less consistent trends were found for practical support, in that socio-demographic trends depended on how practical support was measured. In particular, it depended on whether both personal and organisational sources of support were examined. Gender differences in social support were large and might therefore be expected to contribute to gender differences in health, whereas social class differences in social support were modest, suggesting a minor explanatory role for this factor in accounting for inequalities in health.

Validity of the Malaise Inventory in general population samples

BACKGROUND

The Malaise Inventory is a commonly used self-completion scale for assessing psychiatric morbidity. There is some evidence that it may represent two separate psychological and somatic subscales rather than a single underlying factor of distress. This paper provides further information on the factor structure of the Inventory and on the reliability and validity of the total scale and two sub-scales.

METHODS

Two general population samples completed the full Inventory: over 11,000 subjects from the National Child Development Study at ages 23 and 33, and 544 mothers of adolescents included in the Isle of Wight epidemiological surveys.

RESULTS

The internal consistency of the full 24-item scale and the 15-item psychological subscale were found to be acceptable, but the eight-item somatic sub-scale was less reliable. Factor analysis of all 24 items identified a first main general factor and a second more purely psychological factor. Receiver operating characteristic (ROC) analysis indicated that the validity of the scale held for men and women separately and for different socio-economic groups, by reference to external criteria covering current or recent psychiatric morbidity and service use, and that the psychological sub-scale had no greater validity than the full scale.

CONCLUSIONS

This study did not support the separate scoring of a somatic sub-scale of the Malaise Inventory. Use of the 15-item psychological sub-scale can be justified on the grounds of reduced time and cost for completion, with little loss of reliability or validity, but this approach would not significantly enhance the properties of the Inventory by comparison with the full 24-item scale. Inclusion of somatic items may be more problematic when the full scale is used to compare particular sub-populations with different propensities for physical morbidity, such as different age groups, and in these circumstances it would be a sensible precaution to utilise the 15-item psychological sub-scale.