Childhood infections, vaccinations, and tonsillectomy and risk of first clinical diagnosis of CNS demyelination in the Ausimmune Study

BACKGROUND

The association between childhood vaccinations and infections and risk of multiple sclerosis is unclear; few studies have considered age at vaccination/infection.

OBJECTIVE

To explore age-related associations between childhood vaccinations, infection and tonsillectomy and risk of a first clinical diagnosis of CNS demyelination.

METHODS

Data on case (n = 275, 76.6% female; mean age 38.6 years) and age- and sex-matched control (n = 529) participants in an incident population-based case-control study included self-reported age at time of childhood vaccinations, infections, and tonsillectomy. Conditional logistic regression models were used to calculate adjusted odds ratios (AOR) and 95% confidence intervals (CI).

RESULTS

Poliomyelitis vaccination prior to school-age was associated with increased risk of a first clinical diagnosis of CNS demyelination (AOR = 2.60, 95%CI 1.02-6.68), based on a very small unvaccinated reference group. Late (11-15 years) rubella vaccination (compared to none) was associated with lower odds of being a case (AOR = 0.47, 95%CI 0.27-0.83). Past infectious mononucleosis at 11-15 years (AOR = 2.84, 95%CI 1.0-7.57) and 16-20 years (AOR = 1.92, 95%CI 1.12-3.27) or tonsillectomy in adolescence (11-15 years: AOR = 2.45, 95%CI 1.12-5.35), including after adjustment for IM, were associated with increased risk of a first clinical diagnosis of CNS demyelination.

CONCLUSIONS

Age at vaccination, infection or tonsillectomy may alter the risk of subsequent CNS demyelination. Failing to account for age effects may explain inconsistencies in past findings.

A qualitative study exploring views and experiences of people with stroke undergoing transcranial direct current stimulation and upper limb robot therapy

Background Neurorehabilitation technologies used mainly in research such as robot therapy (RT) and transcranial direct current stimulation (tDCS) can promote upper limb motor recovery after stroke. Understanding the feasibility and efficacy of stroke rehabilitation technologies for upper limb impairments is crucial for effective implementation in practice. Small studies have explored views of RT by people with stroke; however experiences of people receiving tDCS in combination with RT have never been explored. Objective To explore views and experiences of people with sub-acute and chronic stroke that had previously taken part in a randomised controlled trial involving tDCS and RT for their impaired upper limb. Methods An interview study includes open and closed questions. Face-to-face interviews were audio recorded. Open-ended question responses were transcribed and analyzed using thematic analysis; closed questions were analyzed using descriptive analysis. Results Participants felt that RT was enjoyable (90%) and beneficial for their affected arm (100%). From the open question data, it was found that the intervention was effective for the impaired arm especially in the sub-acute stage. Main reported concerns were that tDCS caused painful, itching and burning sensations and RT was sometimes tiring and difficult. Participants recommended that future research should focus on designing a more comfortable method of tDCS and develop a robot that promotes hand movements. Conclusions This study provides new knowledge about the benefits and barriers associated with these technologies which are crucial to the future effective implementation of these tools in practice.

An attention and interpretation bias for illness-specific information in chronic fatigue syndrome

BACKGROUND

Studies have shown that specific cognitions and behaviours play a role in maintaining chronic fatigue syndrome (CFS). However, little research has investigated illness-specific cognitive processing in CFS. This study investigated whether CFS participants had an attentional bias for CFS-related stimuli and a tendency to interpret ambiguous information in a somatic way. It also determined whether cognitive processing biases were associated with co-morbidity, attentional control or self-reported unhelpful cognitions and behaviours.

METHOD

A total of 52 CFS and 51 healthy participants completed self-report measures of symptoms, disability, mood, cognitions and behaviours. Participants also completed three experimental tasks, two designed specifically to tap into CFS salient cognitions: (i) visual-probe task measuring attentional bias to illness (somatic symptoms and disability) v. neutral words; (ii) interpretive bias task measuring positive v. somatic interpretations of ambiguous information; and (iii) the Attention Network Test measuring general attentional control.

RESULTS

Compared with controls, CFS participants showed a significant attentional bias for fatigue-related words and were significantly more likely to interpret ambiguous information in a somatic way, controlling for depression and anxiety. CFS participants had significantly poorer attentional control than healthy individuals. Attention and interpretation biases were associated with fear/avoidance beliefs. Somatic interpretations were also associated with all-or-nothing behaviour and catastrophizing.

CONCLUSIONS

People with CFS have illness-specific biases which may play a part in maintaining symptoms by reinforcing unhelpful illness beliefs and behaviours. Enhancing adaptive processing, such as positive interpretation biases and more flexible attention allocation, may provide beneficial intervention targets.

Medical history, lifestyle, family history, and occupational risk factors for peripheral T-cell lymphomas: the InterLymph Non-Hodgkin Lymphoma Subtypes Project

BACKGROUND

Accounting for 10%-15% of all non-Hodgkin lymphomas in Western populations, peripheral T-cell lymphomas (PTCL) are the most common T-cell lymphoma but little is known about their etiology. Our aim was to identify etiologic risk factors for PTCL overall, and for specific PTCL subtypes, by analyzing data from 15 epidemiologic studies participating in the InterLymph Consortium.

METHODS

A pooled analysis of individual-level data for 584 histologically confirmed PTCL cases and 15912 controls from 15 case-control studies conducted in Europe, North America, and Australia was undertaken. Data collected from questionnaires were harmonized to permit evaluation of a broad range of potential risk factors. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression.

RESULTS

Risk factors associated with increased overall PTCL risk with a P value less than .05 included: a family history of hematologic malignancies (OR = 1.92, 95% CI = 1.30 to 2.84); celiac disease (OR = 17.8, 95% CI = 8.61 to 36.79); eczema (OR = 1.41, 95% CI = 1.07 to 1.85); psoriasis (OR = 1.97, 95% CI = 1.17 to 3.32); smoking 40 or more years (OR = 1.92, 95% CI = 1.41 to 2.62); and employment as a textile worker (ever) (OR = 1.58, 95% CI = 1.05 to 2.38) and electrical fitter (ever) (OR = 2.89, 95% CI = 1.41 to 5.95). Exposures associated with reduced overall PTCL risk included a personal history of allergies (OR = 0.69, 95% CI = 0.54 to 0.87), alcohol consumption (ever) (OR = 0.64, 95% CI = 0.49 to 0.82), and having ever lived or worked on a farm (OR = 0.72, 95% CI = 0.55% to 0.95%). We also observed the well-established risk elevation for enteropathy-type PTCL among those with celiac disease in our data. Conclusions Our pooled analyses identified a number of new potential risk factors for PTCL and require further validation in independent series.

Medical history, lifestyle, and occupational risk factors for hairy cell leukemia: the InterLymph Non-Hodgkin Lymphoma Subtypes Project

BACKGROUND

Little is known about the etiology of hairy cell leukemia (HCL), a rare B-cell lymphoproliferative disorder with marked male predominance. Our aim was to identify key risk factors for HCL.

METHODS

A pooled analysis of individual-level data for 154 histologically confirmed HCL cases and 8834 controls from five case-control studies, conducted in Europe and Australia, was undertaken. Age-, race and/or ethnicity-, sex-, and study-adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression.

RESULTS

The usual patterns for age and sex in HCL were observed, with a median age of 55 years and sex ratio of 3.7 males to females. Cigarette smoking was inversely associated with HCL (OR = 0.51, 95% CI = 0.37 to 0.71) with dose-response relationships observed for duration, frequency, and lifetime cigarette smoking (P(trend) < .001). In contrast, occupation as a farmer was positively associated with HCL (OR = 2.34, 95% CI = 1.36 to 4.01), with a dose-response relationship observed for duration (OR = 1.82, 95% CI = 0.85 to 3.88 for ≤ 10 years vs never; and OR = 2.98, 95% CI = 1.50 to 5.93 for >10 years vs never; P(trend) = .025). Adult height was also positively associated with HCL (OR = 2.69, 95% CI = 1.39 to 5.29 for upper vs lower quartile of height). The observed associations remained consistent in multivariate analysis.

CONCLUSIONS

Our observations of an increased risk of HCL from farming exposures and decreased risk from smoking exposures, independent of one another, support a multifactorial origin and an etiological specificity of HCL compared with other non-Hodgkin lymphoma subtypes. The positive association with height is a novel finding that needs replication.

Comparison of arthroscopic and MRI findings of osteochondral damage in knees

Magnetic resonance imaging (MRI) scans are widely used in the assessment of knees, often prior to arthroscopic procedures. The reporting of osteochondral damage on MRI scans can be variable. The correlation between MRI reports of osteochondral damage and that found at arthroscopy is often inconsistent. A retrospective case-note review of a single-surgeon series of 175 arthroscopic procedures was performed. Eighty-three patients were included in the study. The remainder were excluded if an MRI scan had not been performed or had been performed more than 3-months before surgery. The condition of the articular cartilage demonstrated by MRI was compared to that found at arthroscopy. Data was analysed for presence and extent of osteochondral damage. Comparison between MRI and arthroscopy findings showed high specificity (90%) and negative predictive values (89%) for osteochondral damage but low sensitivity (46%). Cohen's kappa values < 0.2 revealed very poor correlation for the extent of damage. This study demonstrates MRI as a good identifier of osteochondral damage but an unreliable descriptor for such change.

Design & control of a 3D stroke rehabilitation platform

An upper limb stroke rehabilitation system is developed which combines electrical stimulation with mechanical arm support, to assist patients performing 3D reaching tasks in a virtual reality environment. The Stimulation Assistance through Iterative Learning (SAIL) platform applies electrical stimulation to two muscles in the arm using model-based control schemes which learn from previous trials of the task. This results in accurate movement which maximises the therapeutic effect of treatment. The principal components of the system are described and experimental results confirm its efficacy for clinical use in upper limb stroke rehabilitation.

Sun exposure may increase risk of prostate cancer in the high UV environment of New South Wales, Australia: a case-control study

Ultraviolet (UV) radiation in sunlight may influence risk of prostate cancer. In New South Wales (NSW), Australia, we examined the relationship between sun exposure at 30 and 50 years of age and risk of prostate cancer in a case-control study combining the NSW prostate cancer care and outcome study (cases) and the NSW non-Hodgkin's lymphoma study (controls). Prostate cancer risk increased with increasing estimated sun exposure (adjusted OR for highest vs. lowest quartiles of average weekly sun exposure in the warmer months 2.07 95% CI: 1.36-3.15) and this increase was most evident with weekend sun exposure (adjusted OR=5.55, 95% CI: 2.94-10.48). High sun sensitivity was also positively associated with risk for prostate cancer (adjusted OR=1.63, 95% CI: 1.09-2.44). The apparent effects of weekly sun exposure did not vary by disease aggressiveness. Our results suggest that increasing sun exposure in mid-adult years increases prostate cancer risk in a high ambient solar UV environment. Given that previous studies, conducted mainly in low solar UV environments, have generally found evidence of a negative association, our findings suggest there may be a U-shaped relationship between solar UV exposure and prostate cancer. Further studies are needed to test the hypothesis that high solar UV exposure is a risk factor for prostate cancer and to explore possible mechanisms for such an association.

Epstein-Barr virus and multiple sclerosis

This review of the considerable evidence linking Epstein-Barr virus (EBV) infection to risk and disease progression in multiple sclerosis (MS) builds on the background to the virus and its interactions with the human host available in the online supplement (see supplement, available online only). The evidence for a similarity in the geographic patterns of occurrence of MS and EBV infection (with infectious mononucleosis or EBV specific serology used as surrogate markers), when reviewed critically, is very limited. There is strong evidence however that people with MS are more likely to report a past history of infectious mononucleosis (thought to represent initial EBV infection at an older age), and higher titres of EBV specific antibodies are associated with an increased risk of developing MS. Elevated levels of the latter are apparent many years before MS onset (compared with non-MS controls) and there is a dose-response relationship between MS risk and antibody titre, with antibodies to the EBV nuclear antigen-1 particularly important. The evidence in relation to EBV DNA load in blood or CSF is conflicting, as is that in relation to T cell responses to EBV. Several hypotheses that have been proposed to explain the links between EBV and MS risk are reviewed and gaps requiring further research are identified.

The ‘hygiene hypothesis’ and the development of multiple sclerosis

SUMMARY We review evidence linking inadequate microbial exposure in early life to the development of multiple sclerosis (MS). There is some supportive, but not conclusive evidence for a role of a hygienic environment in early life and MS. Population-level studies of MS are consistent with the hygiene hypothesis but are limited by methodological issues. Late infection with Epstein–Barr virus (EBV) has been prospectively associated with MS and must be incorporated into any model where the hygiene hypothesis is implicated in the development of MS. One possibility is that inadequate microbial exposure in early life contributes to a dysregulated host immune response to EBV. Two areas of particular interest include the potential role for helminthic infection in biasing the human immune response away from the immune profile associated with MS and also the role of microbial exposure in training the development of the EBV-specific immune response.

Expanded dog leukocyte antigen (DLA) single nucleotide polymorphism (SNP) genotyping reveals spurious class II associations

The dog leukocyte antigen (DLA) system contains many of the functional genes of the immune system, thereby making it a candidate region for involvement in immune-mediated disorders. A number of studies have identified associations between specific DLA class II haplotypes and canine immune hemolytic anemia, thyroiditis, immune polyarthritis, type I diabetes mellitus, hypoadrenocorticism, systemic lupus erythematosus-related disease complex, necrotizing meningoencephalitis (NME) and anal furunculosis. These studies have relied on sequencing approximately 300 bases of exon 2 of each of the DLA class II genes: DLA-DRB1, DLA-DQA1 and DLA-DQB1. In the present study, an association (odds ratio=4.29) was identified by this method between Weimaraner dogs with hypertrophic osteodystrophy (HOD) and DLA-DRB1∗01501. To fine map the association with HOD, a genotyping assay of 126 coding single nucleotide polymorphisms (SNPs) from across the entire DLA, spanning a region of 2.5 Mb (3,320,000-5,830,000) on CFA12, was developed and tested on Weimaraners with HOD, as well as two additional breeds with diseases associated with DLA class II: Nova Scotia duck tolling retrievers with hypoadrenocorticism and Pug dogs with NME. No significant associations were found between Weimaraners with HOD or Nova Scotia duck tolling retrievers with hypoadrenocorticism and SNPs spanning the DLA region. In contrast, significant associations were found with NME in Pug dogs, although the associated region extended beyond the class II genes. By including a larger number of genes from a larger genomic region, a SNP genotyping assay was generated that provides coverage of the extended DLA region and may be useful in identifying and fine mapping DLA associations in dogs.

The role of latitude, ultraviolet radiation exposure and vitamin D in childhood asthma and hayfever: an Australian multicenter study

Observations of increasing allergy prevalence with decreasing distance from the Equator and positive associations with ambient ultraviolet radiation have contributed to a growing interest in the possible role of vitamin D in the etiology of allergy. The aims of this study were to describe any latitudinal variation in the prevalence of childhood allergy in Australia and to evaluate, in parallel, the individual associations between ultraviolet radiation (UVR)- and vitamin D-related measures and hayfever asthma and both conditions. Participants were population-based controls who took part in a multicenter case-control study, aged 18-61 yr and resident in one of four study regions ranging in latitude from 27°S to 43°S. Data were derived from a self-administered questionnaire, interview and examination by a research officer and biologic sampling. Latitude and longitude coordinates were geocoded from participants' residential locations and climatic data were linked to postcodes of current residence. Stored serum was analyzed for 25-hydroxyvitamin D concentrations and silicone rubber casts of the skin were used as an objective measure of cumulative actinic damage. There was an inverse latitude gradient for asthma (a 9% decrease per increasing degree of latitude); however, this pattern did not persist after adjusting for average daily temperature. There was no association between any of the UVR- or vitamin D-related measures and childhood asthma, but greater time in the sun in winter between the ages 6-15 yr was associated with an increase in the odds of having hayfever [adjusted odds ratios (OR) 1.29; 95% CI 1.01-1.63]. Oral supplementation with cod liver oil in childhood increased the odds of a history of having both asthma and hayfever (2.87; 1.00-8.32). Further investigation of the possible role of early vitamin D supplementation in the development of allergy is warranted. Our results also suggest that solar exposure during childhood may be important in allergic sensitization. Plausible explanations, including biologic mechanisms, exist for both observations.

Tumor necrosis factor (TNF) and lymphotoxin-alpha (LTA) polymorphisms and risk of non-Hodgkin lymphoma in the InterLymph Consortium

In an International Lymphoma Epidemiology Consortium pooled analysis, polymorphisms in 2 immune-system-related genes, tumor necrosis factor (TNF) and interleukin-10 (IL10), were associated with non-Hodgkin lymphoma (NHL) risk. Here, 8,847 participants were added to previous data (patients diagnosed from 1989 to 2005 in 14 case-control studies; 7,999 cases, 8,452 controls) for testing of polymorphisms in the TNF -308G>A (rs1800629), lymphotoxin-alpha (LTA) 252A>G (rs909253), IL10 -3575T>A (rs1800890, rs1800896), and nucleotide-binding oligomerization domain containing 2 (NOD2) 3020insC (rs2066847) genes. Odds ratios were estimated for non-Hispanic whites and several ethnic subgroups using 2-sided tests. Consistent with previous findings, odds ratios were increased for "new" participant TNF -308A carriers (NHL: per-allele odds ratio (OR(allelic)) = 1.10, P(trend) = 0.001; diffuse large B-cell lymphoma (DLBCL): OR(allelic) = 1.23, P(trend) = 0.004). In the combined population, odds ratios were increased for TNF -308A carriers (NHL: OR(allelic) = 1.13, P(trend) = 0.0001; DLBCL: OR(allelic) = 1.25, P(trend) = 3.7 x 10(-6); marginal zone lymphoma: OR(allelic) = 1.35, P(trend) = 0.004) and LTA 252G carriers (DLBCL: OR(allelic) = 1.12, P(trend) = 0.006; mycosis fungoides: OR(allelic) = 1.44, P(trend) = 0.015). The LTA 252A>G/TNF -308G>A haplotype containing the LTA/TNF variant alleles was strongly associated with DLBCL (P = 2.9 x 10(-8)). Results suggested associations between IL10 -3575T>A and DLBCL (P(trend) = 0.02) and IL10 -1082A>G and mantle cell lymphoma (P(trend) = 0.04). These findings strengthen previous results for DLBCL and the LTA 252A>G/TNF -308A locus and provide robust evidence that these TNF/LTA gene variants, or others in linkage disequilibrium, are involved in NHL etiology.

Feasibility of iterative learning control mediated by functional electrical stimulation for reaching after stroke

BACKGROUND

An inability to perform tasks involving reaching is a common problem following stroke. Evidence supports the use of robotic therapy and functional electrical stimulation (FES) to reduce upper limb impairments, but current systems may not encourage maximal voluntary contribution from the participant because assistance is not responsive to performance.

OBJECTIVE

This study aimed to investigate whether iterative learning control (ILC) mediated by FES is a feasible intervention in upper limb stroke rehabilitation.

METHODS

Five hemiparetic participants with reduced upper limb function who were at least 6 months poststroke were recruited from the community. No participants withdrew.

INTERVENTION

Participants undertook supported tracking tasks using 27 different trajectories augmented by responsive FES to their triceps brachii muscle, with their hand movement constrained in a 2-dimensional plane by a robot. Eighteen 1-hour treatment sessions were used with 2 participants receiving an additional 7 treatment sessions.

OUTCOME MEASURES

The primary functional outcome measure was the Action Research Arm Test (ARAT). Impairment measures included the upper limb Fugl-Meyer Assessment (FMA), tests of motor control (tracking accuracy), and isometric force.

RESULTS

Compliance was excellent and there were no adverse events. Statistically significant improvements were measured (P <or= .05) in FMA motor score, unassisted tracking for 3 out of 4 trajectories, and in isometric force over 5 out of 6 directions. Changes in ARAT were not statistically significant.

CONCLUSION

This study has demonstrated the feasibility of using ILC mediated by FES for upper limb stroke rehabilitation.

Eczema, birth order, and infection

The association between infections occurring in the first 2 years of life and development of eczema was investigated in 1,782 control children from a national population-based case-control study in the United Kingdom conducted over the period 1991-1996. Dates of eczema and infectious diagnoses were ascertained from contemporaneously collected primary care records. Children diagnosed with eczema before the age of 2 years had more prior clinically diagnosed infections recorded than did children without eczema (rate ratio = 1.26, 95% confidence interval (CI): 1.18, 1.36). The difference in infection rates between children with and without eczema was apparent from birth and throughout the first 2 years of life. As expected, compared with children of second or higher birth order, those firstborn were at increased risk of eczema (p = 0.020); however, the relation between eczema and prior infection was evident only among children of second or higher birth order and not among firstborn children (rate ratio = 1.45, 95% CI: 1.32, 1.59, and rate ratio = 1.08, 95% CI: 0.98, 1.20, respectively). The authors' results are consistent with the notion that the association between birth order and eczema is unlikely to be attributable to variations in early infectious exposure.

Atopy, exposure to pesticides and risk of non-Hodgkin lymphoma

Pesticide exposure has been associated with non-Hodgkin lymphoma (NHL) risk in a number of studies, and two recent studies suggest that the increased risk may be confined to those with a history of asthma. We examined the interaction between occupational pesticide exposure and atopy on risk of NHL in an Australian population-based case-control study. Incident cases (n = 694) were diagnosed in New South Wales or the Australian Capital Territory between 2000 and 2001 and controls (n = 694) were randomly selected from electoral rolls and frequency-matched to cases by age, sex and state of residence. Occupational pesticide exposure was determined by an expert occupational hygienist's assessment of job-specific questionnaires administered by telephone. History of atopy (asthma, hay fever, eczema and food allergy) was self-reported. Logistic regression models included the three matching variables, ethnicity and sun exposure. The OR for NHL with substantial pesticide exposure and any history of asthma was 3.07 (95% CI 0.55-17.10) and with substantial pesticide exposure and no asthma history it was 4.23 (95% CI 1.76-10.16). The p-value for interaction was 0.29. A similar pattern of risk was observed for each of the pesticide subtypes; for asthma at various times of life; for hay fever, eczema, food allergy and any atopy, in men only and for follicular lymphomas only. Although this study had limited power, the findings do not suggest modification of the association between pesticide exposure and NHL risk by asthma or atopic disease more generally.

Occupational exposure to ionizing and non-ionizing radiation and risk of non-Hodgkin lymphoma

OBJECTIVE

To investigate the association between occupational exposure to ionizing, ultraviolet (UV), radiofrequency (RF) and extremely low frequency (ELF) radiation and risk of developing non-Hodgkin lymphoma (NHL) in a population-based case-control study.

METHODS

The study population consisted of 694 NHL cases, first diagnosed between 1 January 2000 and 31 August 2001, and 694 controls from two regions in Australia, matched by age, sex and region of residence. A detailed occupation history was first obtained using a lifetime calendar and a telephone interview. Exposure to radiation was then assessed using a Finnish job-exposure matrix (FINJEM). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from logistic regression models that included the matching variables as covariates.

RESULTS

For ionizing radiation, the ORs were close to unity. For UV and ELF radiation, the highest exposed group of workers had ORs of 1.32 (95% CI=0.96-1.81) and 1.25 (95% CI=0.91-1.72), respectively. For UV radiation there was a positive dose-response when exposure was lagged by 5 and 10 years (P for trend 0.04 for both lag periods). Workers in the upper tertile of exposure for RF radiation had an OR of 3.15 (95% CI=0.63-15.87), but the estimate was based on very small numbers.

CONCLUSIONS

Our results do not provide support for an association between NHL and occupational exposure to ionizing or ELF radiation. For UV radiation, our findings are consistent with a weak positive association. Further investigation focusing on UV and RF radiation and NHL is required.

Personal sun exposure and risk of non Hodgkin lymphoma: A pooled analysis from the Interlymph Consortium

In 2004-2007 4 independent case-control studies reported evidence that sun exposure might protect against NHL; a fifth, in women only, found increased risks of NHL associated with a range of sun exposure measurements. These 5 studies are the first to examine the association between personal sun exposure and NHL. We report here on the relationship between sun exposure and NHL in a pooled analysis of 10 studies participating in the International Lymphoma Epidemiology Consortium (InterLymph), including the 5 published studies. Ten case-control studies covering 8,243 cases and 9,697 controls in the USA, Europe and Australia contributed original data for participants of European origin to the pooled analysis. Four kinds of measures of self-reported personal sun exposure were assessed at interview. A two-stage estimation method was used in which study-specific odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for potential confounders including smoking and alcohol use, were obtained from unconditional logistic regression models and combined in random-effects models to obtain the pooled estimates. Risk of NHL fell significantly with the composite measure of increasing recreational sun exposure, pooled OR = 0.76 (95% CI 0.63-0.91) for the highest exposure category (p for trend 0.01). A downtrend in risk with increasing total sun exposure was not statistically significant. The protective effect of recreational sun exposure was statistically significant at 18-40 years of age and in the 10 years before diagnosis, and for B cell, but not T cell, lymphomas. Increased recreational sun exposure may protect against NHL.

Specific infections, infection-related behavior, and risk of non-Hodgkin lymphoma in adults

Infections were examined as possible risk factors for non-Hodgkin lymphoma in a population-based case-control study in New South Wales and the Australian Capital Territory, Australia. Incident cases (n = 694) had no history of HIV infection or transplantation. Controls (n = 694) were randomly selected from electoral rolls and frequency matched to cases by age, sex, and area of residence. A postal questionnaire and telephone interview measured history of specific infections, occupational exposures, and behavioral and other risk factors for infection. Blood samples were tested for antibodies to human T-lymphotrophic virus type I and hepatitis C virus. Logistic regression models included the three matching variables and ethnicity. There was no association between risk of non-Hodgkin lymphoma and any of the variables analyzed, including sexually transmitted infections, sexual behavior, blood transfusions, influenza, acne, and either occupational or domestic exposure to zoonotic infections. Non-Hodgkin lymphoma risk was nonsignificantly elevated (odds ratio, 2.99; 95% confidence interval, 0.78-11.51) for those with a history of injecting drug use. Three cases and two controls (odds ratio, 1.32; 95% confidence interval, 0.22-7.98) tested positive to hepatitis C virus infection and none tested positive to human T-lymphotrophic virus type I/II infection. This study provides consistent evidence that sexually transmitted infections and zoonoses are not risk factors for non-Hodgkin lymphoma.

Occupational exposure to power frequency magnetic fields and risk of non-Hodgkin lymphoma

OBJECTIVES

To investigate the risk of non-Hodgkin lymphoma (NHL) using a job-exposure matrix (JEM) to assess exposure to occupational magnetic fields at the power frequencies of 50/60 Hz.

METHODS

The study population consisted of 694 cases of NHL, first diagnosed between 1 January 2000 and 31 August 2001, and 694 controls from two regions in Australia, matched by age, sex and region of residence. A detailed occupational history was given by each subject. Exposure to power frequency magnetic fields was estimated using a population-based JEM which was specifically developed in the United States to assess occupational magnetic field exposure. The cumulative exposure distribution was divided into quartiles and adjusted odds ratios were calculated using the lowest quartile as the referent group.

RESULTS

For the total work history, the odds ratio (OR) for workers in the upper quartile of exposure was 1.48 (95% CI 1.02 to 2.16) compared to the referent (p value for trend was 0.006). When the exposure was lagged by 5 years the OR was 1.59 (95% CI 1.07 to 2.36) (p value for trend was 0.003). Adjusting for other occupational exposures did not significantly alter the results.

CONCLUSIONS

These findings provide weak support for the hypothesis that occupational exposure to 50/60 Hz magnetic fields increases the risk of NHL.

WHO non-Hodgkin's lymphoma classification by criterion-based report review followed by targeted pathology review: an effective strategy for epidemiology studies

In a previous criterion-based pathology report review of 717 cases of non-Hodgkin's lymphoma in an Australian population-based epidemiologic study, a WHO category could be assigned in 91% of cases, but confidence in this classification was high in only 57.5%. Given this lack of confidence, a pathology review was done in a subset of 315 cases, with the aims of assigning a WHO classification category and the corresponding International Classification of Diseases for Oncology, Third Edition code in all cases previously unclassified or classified with low confidence and testing the accuracy of report review in assigning a confident WHO classification. After pathology review, 10 cases were ineligible (not non-Hodgkin's lymphoma, 3.2%) and 99% (301 of 305) of the remainder were assigned a WHO classification, with high confidence in 87% (261 of 301). There was 78% overall agreement between the WHO classification assigned by report review and pathology review, with 92% agreement when there was high confidence in the report review classification and 69% agreement when there was low confidence. Eighteen percent of follicular lymphomas and 23% of diffuse large B-cell lymphomas were reclassified. The pathology review increased the accuracy of WHO classification by an estimated 12.5% in the 694 cases who were still eligible in the study. Although a potential error rate of 7.5% remained, reviewing more cases, or not reviewing any cases classified with high confidence, would have produced only a small change in accuracy. Criterion-based pathology report review of all cases followed by selective pathology review in cases classified with low confidence is recommended as a cost-saving and accurate strategy for pathology review in large epidemiologic studies.

Factors determining the optimal body site and method for obtaining punch biopsies of human skin as a tissue in which to assess pharmacodynamic and pharmacokinetic endpoints in drug development studies

There are potential advantages to detecting pharmacodynamic (PD) and pharmacokinetic (PK) endpoints in a tissue-based compartment such as the skin during the development of molecularly targeted drugs. We explored regional differences between inner arm, inner thigh, lower back and buttocks in 12 healthy male Caucasian volunteers in the tolerability of skin biopsy procedures; the Ki67 proliferation index; the frequency of detecting hair follicles and sweat glands; and the percentage of melanocytes. We also explored the amounts of tissue and protein obtained, and two separate methods of splitting biopsies for processing in mutually exclusive media. Biopsies from all body sites were well tolerated. The subjective ranking order was inner arm > buttocks = back > thigh. There were no statistically significant differences in the Ki67 labelling index (P > 0.05). The frequency of detecting sweat glands was the same in all body sites, but the frequency of detecting hair follicles was higher in back and buttock, compared to arm and thigh. The percentage of melanocytes was significantly lower in the buttocks compared to the back and thigh (P < 0.05), but not compared to the arm (P = 0.07). A 4-mm punch biopsy yielded a mean of 16.8 mg of tissue (range: 9-28 mg) and 160 microg of protein (range: 80-270 microg). In vivo sample splitting, by following a 2-mm punch with a 4-mm overpunch, had a shorter time from devascularisation to immersion into processing medium than ex vivo dissection of a 4-mm sample, which may be of importance to the assessment of labile endpoints. We conclude that multiple punch biopsies of the skin are feasible, with the buttocks representing the studied body site with the optimal balance between tolerability, hair follicle density and melanocyte density for obtaining tissue in which to assess PD and PK endpoints during drug development studies.

Occupational exposure to pesticides and risk of non-Hodgkin's lymphoma

Pesticide exposure may be a risk factor for non-Hodgkin's lymphoma, but it is not certain which types of pesticides are involved. A population-based case-control study was undertaken in 2000-2001 using detailed methods of assessing occupational pesticide exposure. Cases with incident non-Hodgkin's lymphoma in two Australian states (n = 694) and controls (n = 694) were chosen from Australian electoral rolls. Logistic regression was used to estimate the risks of non-Hodgkin's lymphoma associated with exposure to subgroups of pesticides after adjustment for age, sex, ethnic origin, and residence. Approximately 10% of cases and controls had incurred pesticide exposure. Substantial exposure to any pesticide was associated with a trebling of the risk of non-Hodgkin's lymphoma (odds ratio = 3.09, 95% confidence interval: 1.42, 6.70). Subjects with substantial exposure to organochlorines, organophosphates, and "other pesticides" (all other pesticides excluding herbicides) and herbicides other than phenoxy herbicides had similarly increased risks, although the increase was statistically significant only for "other pesticides." None of the exposure metrics (probability, level, frequency, duration, or years of exposure) were associated with non-Hodgkin's lymphoma. Analyses of the major World Health Organization subtypes of non-Hodgkin's lymphoma suggested a stronger effect for follicular lymphoma. These increases in risk of non-Hodgkin's lymphoma with substantial occupational pesticide exposure are consistent with previous work.

Specific inhibition of the endothelin A receptor with ZD4054: clinical and pre-clinical evidence

Activation of the endothelin A receptor (ET(A)) by endothelin-1 (ET-1) mediates events that regulate mitogenesis, apoptosis, angiogenesis and metastasis in tumours. Specific blockade of ET(A) may have anticancer effects, while retaining beneficial endothelin B receptor (ET(B))-mediated effects such as apoptosis and clearance of ET-1. ZD4054 is an orally active, specific ET(A) antagonist in clinical development. In receptor-binding studies, ZD4054 specifically bound to ET(A) with high affinity; no binding was detected at ET(B). In a randomised placebo-controlled trial in eight healthy volunteers, a single oral dose of ZD4054 reduced forearm vasoconstriction in response to brachial artery infusion of ET-1, thus providing clinical evidence of ET(A) blockade. ET(B) blockade was assessed in an ascending, single-dose, placebo-controlled trial in 28 volunteers. For all doses of ZD4054, mean plasma ET-1 concentrations measured at 4 and 24 h were within the placebo reference range (a rise in ET-1 would indicate ET(B) blockade) and there was no evidence of dose-related changes. These data confirm the specificity of ZD4054 for ET(A), with no activity at ET(B) in a clinical or preclinical setting. As a result of this specificity, ZD4054 has the potential to block multiple ET(A)-induced pathological processes, while allowing beneficial ET(B)-mediated processes to continue, which may, in turn, lead to an effective cancer therapy.

Assessing proliferation, cell-cycle arrest and apoptotic end points in human buccal punch biopsies for use as pharmacodynamic biomarkers in drug development

Easily accessible normal tissues expressing the same molecular site(s) of drug action as malignant tissue offer an enhanced potential for early proof of anticancer drug mechanism and estimation of the biologically effective dose. Studies were undertaken in healthy male volunteers to assess the tolerability of single and multiple (four in 24 h) 3 mm punch biopsies of the buccal mucosa, and to determine the feasibility of detecting and quantifying a range of proliferation, cell-cycle arrest and apoptosis markers by immunohistochemistry (IHC) for use as potential pharmacodynamic (PD) end points. The biopsy procedure was well tolerated with 100% of volunteers stating that they would undergo single (n=10) and multiple (n=12) biopsies again. Total retinoblastoma protein (pRb), phosphorylated pRb (phospho-pRb), total p27, phosphorylated p27 (phospho-p27), phosphorylated-histone H3 (phospho-HH3), p21, p53, Cyclin A, Cyclin E, Ki67 all produced good signal detection, but M30, cleaved caspase 3 and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling did not. Total pRb, phospho-pRb, total p27 and phospho-p27 were quantified further in a multiple biopsy study to allow components of variability to be addressed to inform future sizing decisions on intervention studies. Neither site of biopsy within the oral cavity, nor the nominal time of biopsy had any significant impact on any of the four markers expression levels. Inter- and intrasubject coefficients of variation (CVs) that could be used to size future intervention studies for pRb, phospho-pRb, total p27 and phospho-p27 were 14, 19, 18 and 16%; and 18, 29, 25 and 19%, respectively. In conclusion, quantitation of such markers in 3 mm buccal punch biopsies would be suitable to explore as PD end points within intervention studies of drugs acting on these pathways.

Plucked human hair as a tissue in which to assess pharmacodynamic end points during drug development studies

We have demonstrated the feasibility of detecting and quantifying six cell-cycle-related nuclear markers (Ki67, pRb, p27, phospho-p27 (phosphorylated p27), phospho-pRb (phosphorylated pRb), phospho-HH3 (phosphorylated histone H3)) in plucked human scalp and eyebrow hair. Estimates of the proportion of plucked hairs that are lost or damaged during processing plus the intra- and intersubject variability of each nuclear marker with these techniques are provided to inform sizing decisions for intervention studies with drugs potentially impacting on these markers in the future.

Birth order, atopy, and risk of non-Hodgkin lymphoma

BACKGROUND

Immune deficiency is a strong risk factor for non-Hodgkin lymphoma (NHL), but whether or not other forms of immune dysregulation are associated with NHL risk is unknown. We investigated associations between atopy, which is associated with a Th2-dominant immune response, and NHL risk. Because late birth order and childhood crowding are inversely associated with atopy, we also investigated their associations with NHL risk.

METHODS

We carried out a population-based case-control study among adults aged 20-74 years in New South Wales and the Australian Capital Territory, Australia. NHL patients without clinically apparent immune deficiency (N = 704) were selected from a cancer registry, and control subjects (N = 694) were randomly selected from state electoral rolls and frequency-matched to case patients by age, sex, and area of residence. Birth order, childhood crowding, and history of atopic conditions (hay fever, asthma, eczema, and specific allergies) were assessed by questionnaire and interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from logistic regression models that included the matching variables as covariates.

RESULTS

The odds ratios for developing NHL were 0.52 (95% CI = 0.32 to 0.84) for only children, 0.55 (95% CI = 0.40 to 0.75) for first-born children, 0.70 (95% CI = 0.51 to 0.96) for second-born children, and 0.81 (0.57 to 1.14) for third-born children (all compared with fourth- or later-born children) (P(trend)<.001). Indicators of crowding in later childhood, such as sharing a bed or bedroom, were not associated with NHL risk. A history of atopic conditions was associated with a reduced risk of NHL; this reduction was statistically significant for hay fever (OR = 0.65, 95% CI = 0.52 to 0.82) and food allergies (OR = 0.29, 95% CI = 0.20 to 0.42).

CONCLUSIONS

Early birth order and its immunologic consequence, a Th2-dominated immune response, as reflected by a history of atopic disease, are associated with a reduced risk of NHL.

Cigarette Smoking and Risk of Non-Hodgkin Lymphoma: A Pooled Analysis from the International Lymphoma Epidemiology Consortium (InterLymph)

BACKGROUND

The International Lymphoma Epidemiology Consortium (InterLymph) provides an opportunity to analyze the relationship between cigarette smoking and non-Hodgkin lymphoma with sufficient statistical power to consider non-Hodgkin lymphoma subtype. The results from previous studies of this relationship have been inconsistent, likely due to the small sample sizes that arose from stratification by disease subtype. To clarify the role of cigarette smoking in the etiology of non-Hodgkin lymphoma, we conducted a pooled analysis of original patient data from nine case-control studies of non-Hodgkin lymphoma conducted in the United States, Europe, and Australia.

METHODS

Original data were obtained from each study and uniformly coded. Risk estimates from fixed-effects and two-stage random-effects models were compared to determine the impact of interstudy heterogeneity. Odds ratios (OR) and 95% confidence intervals (95% CI) were derived from unconditional logistic regression models, controlling for study center, age, sex, and race.

RESULTS

In our pooled study population of 6,594 cases and 8,892 controls, smoking was associated with slightly increased risk estimates (OR, 1.07; 95% CI, 1.00-1.15). Stratification by non-Hodgkin lymphoma subtype revealed that the most consistent association between cigarette smoking and non-Hodgkin lymphoma was observed among follicular lymphomas (n = 1452). Compared with nonsmokers, current smokers had a higher OR for follicular lymphoma (1.31; 95% CI, 1.12-1.52) than former smokers (1.06; 95% CI, 0.93-1.22). Current heavy smoking (> or = 36 pack-years) was associated with a 45% increased OR for follicular lymphoma (1.45; 95% CI, 1.15-1.82) compared with nonsmokers.

CONCLUSIONS

Cigarette smoking may increase the risk of developing follicular lymphoma but does not seem to affect risk of the other non-Hodgkin lymphoma subtypes we examined. Future research is needed to determine the biological mechanism responsible for our subtype-specific results.

Recurrent miscarriage and long-term thrombosis risk: a case–control study

BACKGROUND

Recurrent miscarriage has been associated with antiphospholipid syndrome (APS) and other prothombotic conditions. We tested the hypothesis that women diagnosed as having APS as an aetiological factor for their miscarriages were at higher risk of thrombosis than those with idiopathic recurrent miscarriage.

METHODS

A retrospective case-control study was performed using validated questionnaires. A total of 141 women with recurrent miscarriage and APS alone were matched with 141 women with idiopathic recurrent miscarriage for age, number and type of pregnancy loss and number of years of follow-up. A subgroup of eight women included those who initially presented with recurrent miscarriage, thrombosis and APS.

RESULTS

The mean length of follow-up was 7.3 years and response rate 74%. The incidence of thrombosis was similar in the recurrent miscarriage and APS women (6/1000 women-years) and in the idiopathic recurrent miscarriage women (2/1000 women-years) (P = 0.18). All eight women who presented with recurrent miscarriage, APS and thrombosis reported further thrombotic events.

CONCLUSIONS

Both idiopathic and APS-associated recurrent miscarriage were associated with a similar long-term risk of thrombosis.

An investigation of components of variance and tachyphylaxis in a placebo-controlled intravenous tyramine study

AIMS

To explore inter- and intra-volunteer variability for the dose of intravenous tyramine eliciting a 20 mmHg increase in systolic blood pressure from baseline (TYR20) and to evaluate potential tachyphylaxis.

METHODS

Twelve healthy volunteers received blinded placebo-controlled ascending and descending sequences of intravenous tyramine injections on two separate occasions. The TYR20 was derived by linear interpolation, using three interventions to deal with missing data.

RESULTS

Analysis of covariance (ancova) demonstrated no significant difference in TYR20 between sequences, regardless of the missing data methodology applied. Inter-volunteer variability was 2.4-3.4 times larger than within-volunteer variability. No evidence of tachyphylaxis was seen using either the sign test or generalized additive models.

CONCLUSIONS

Since inter-volunteer variability was greater than intra-volunteer variability, a crossover study design would be a more efficient study design, and the descending sequence of injections could be omitted since tachyphylaxis was not demonstrated.

Use of the WHO lymphoma classification in a population-based epidemiological study

BACKGROUND

Non-Hodgkin's lymphoma (NHL) is pathologically diverse. Epidemiological investigations into its increasing incidence and aetiology require accurate subtype classification.

PATIENTS AND METHODS

Available pathology reports of 717 cases aged from 20 to 74 years in an Australian, population-based epidemiological study of NHL were reviewed by one anatomical pathologist to assign a World Health Organization (WHO) classification category. High or low confidence was assigned to the diagnosis of NHL, cell phenotype and WHO category and reasons given for low confidence.

RESULTS

The most informative biopsy reports were from open tissue biopsy (79% of cases), tissue core biopsy (8%), cytology (4%) and bone marrow (9%); 8% of cases had inadequate biopsies for diagnostic purposes. Immunohistochemistry or flow cytometry reports were available for 96% of cases, gene rearrangement studies for 6% and cytogenetics for 3%. The reviewer assigned high confidence to the diagnosis of NHL in 93% of cases and also the phenotype in 88%. While a WHO classification could be assigned in 91% of cases, confidence was high in only 57.5%; insufficient immunophenotyping was the commonest reason for low confidence.

CONCLUSIONS

Expert pathology review of a population-based sample of NHL can provide a WHO classification category for most cases. A high level of confidence in the classification, however, would require review of diagnostic material and additional phenotyping.

Pigmentary characteristics, sun sensitivity and non-Hodgkin lymphoma

We report on pigmentary characteristics, sun sensitivity and some other possible risk factors for non-Hodgkin lymphoma (NHL) in people 20-74 years of age. A statewide case-control study was conducted in New South Wales, Australia, with population-based sampling of cases (n = 704) and controls (n = 694). Risk of NHL was increased in subjects with hazel eyes (OR = 1.48; 95% CI = 1.07-2.04), very fair skin (OR = 1.44; 95% CI = 1.01-2.07) and poor ability to tan (OR = 1.70; 95% CI = 1.06-2.71). Risk with mild facial freckling as a child (OR = 0.77; 95% CI = 0.59-0.99) was reduced relative to that with no or moderate to severe freckling. Smokers were not at increased risk of NHL. A past history of treatment for skin cancer was associated with a slight nonsignificant increase in risk. Previous radiotherapy and chemotherapy were associated with 1.5- to 2-fold increases in risk but with wide confidence intervals. These results provide weak support for the possibility that sun sensitivity or perhaps sun exposure increases risk of NHL.

Sun exposure may protect against non-Hodgkin lymphoma: A case-control study

Ultraviolet radiation is a hypothesised risk factor for non-Hodgkin lymphoma (NHL) but no epidemiological study has examined this association using direct measures of sun exposure in individuals. Adults aged 20-74 years living in NSW and ACT, Australia, were the study population. Cases (704 of 829 invited to take part, 85%) were diagnosed January 2000 to August 2001. Controls (694 of 1,136 invited to take part, 61%) were randomly selected from state electoral rolls and frequency-matched to cases by age, sex and state of residence. A self-administered questionnaire and telephone interview measured outdoor hours on working and nonworking days and vacations at 10, 20, 30, 40, 50 and 60 years of age. Logistic regression models of NHL and sun exposure contained the 3 matching variables, ethnicity and sun sensitivity measures as covariates. Contrary to expectations, risk of NHL fell with increasing reported sun exposure hours. Relative to 1.0 for the lowest quarter of total sun exposure hours, the odds ratios (ORs) for successively higher quarters were 0.72 (95% CI 0.53-0.98), 0.66 (0.48-0.91) and 0.65 (0.46-0.91) (p(trend)=0.01). The association of sun exposure on nonworking days with NHL was stronger; OR for highest quarter 0.47 (0.34-0.66) (p(trend)=0.0001). Risk also fell with sun exposure on vacations; OR for highest quarter 0.60 (0.43-0.85) (p(trend)=0.003). These associations appeared strongest in women and in childhood. There was little evident trend in risk with exposure on working day. Our results provide strong statistical evidence for an inverse association between sun exposure and NHL. Increasing evidence that vitamin D may protect against cancer makes UV-mediated synthesis of vitamin D a plausible mechanism whereby sun exposure might protect against NHL.

Assessment of the effect of dextromethorphan and ketamine on the acute nociceptive threshold and wind-up of the second pain response in healthy male volunteers

AIMS

The aim of this study was to assess the efficacy of dextromethorphan and ketamine relative to placebo on the acute nociceptive threshold and wind-up of second pain response in healthy male volunteers.

METHODS

The trial was a randomized, double-blind, placebo-controlled, three period crossover, double dummy design in 12 healthy male volunteers. During each of the three periods (which were separated by a 1 week washout period) each volunteer received either a single oral dose of 0.7 mg kg(-1) dextromethorphan and placebo to ketamine, or placebo to dextromethorphan followed by a single intravenous injection of 0.375 mg kg(-1) ketamine, or placebo to both dextromethorphan and ketamine. The trial did not schedule administration of both ketamine and dextromethorphan together. Acute nociceptive thresholds and wind-up of second pain were measured in the skin of the thenar eminence of the ventral surfaces of the right and left hands, using a SOMEDIC thermotest apparatus, before and at the estimated tmax for dextromethorphan (i.e. 2.15 h). Blood pressure and heart rate were also monitored before dosing and after the dosing regimen.

RESULTS

Neither dextromethorphan nor ketamine had any significant effect on acute nociceptive thresholds on either hand (P>0.05). Moreover, dextromethorphan was without any significant effect (P>0.05) on the wind-up of the second pain response on either hand. The lsmean number of stimuli tolerated vs placebo (95% confidence intervals of the difference in number of stimuli in parentheses) were 15.84 vs 16.48 (-5.52, 4.24) and 11.75 vs 15.25 (-11.89, 4.90) for left- and right-hand, respectively, following dextromethorphan administration. In contrast ketamine produced significant reductions in wind-up to second pain in both the left and right hands (P=0.0002 and 0.0386, respectively). The lsmean numbers of stimuli tolerated vs placebo (95% confidence intervals of the difference in number of stimuli in parentheses) were 28.41 vs 16.48 (6.60, 17.25) and 25.00 vs 15.25 (0.58, 18.93) for left- and right-hand, respectively.

CONCLUSIONS

Wind-up of second pain induced by noxious heat is sensitive to intervention by ketamine, which is known to block the NMDA receptor. These data infer that the wind-up phenomenon evoked by noxious heat involves the activation of NMDA receptors. This volunteer model of pain may have utility in the evaluation of agents that modulate their antinociceptive actions via NMDA mechanisms.

Associations of CCR5, CCR2, and stromal cell-derived factor 1 genotypes with human immunodeficiency virus disease progression in patients receiving nucleoside therapy

Genotype data for CCR5, CCR2, and stromal cell-derived factor 1 (SDF-1) were obtained from 354 human immunodeficiency virus type 1 (HIV-1)-positive subjects who were being treated with nucleosides. Associations with HIV-1 load, HIV syncytium-inducing (SI) phenotype, CD4 cell count, and disease progression were analyzed. No differences in HIV-1 load or CD4 cell count were observed between wild type (+) and variant genotypes. Changes from non-SI to SI viral phenotype were more frequent in heterozygotes with a 32-bp deletion (Delta32) in the CCR5 gene than in + homozygotes (40% vs. 7%; P=.01). In a multivariate analysis, heterozygous CCR5 Delta32 was associated with reduced hazard of progression (hazard ratio, 0.32; P=.02). Subjects homozygous for the SDF-1 3'A variant had more-rapid disease progression (P=.008). The SDF-1 homozygous 3'A variant was related to more-rapid disease progression, and CCR5 Delta32 was associated with reduced rates of hazard for disease progression in nucleoside-treated subjects.

Evaluation of a (pilot) stage-tailored brief smoking cessation intervention among hospital patients presenting to a hospital pre-admission clinic

Despite the significant benefits of advising all smokers to quit, hospital patients who smoke do not systematically receive this advice. This study sought to determine the prevalence of smoking, attitudes of patients towards not smoking while in hospital, and the feasibility and effectiveness of a brief smoking cessation intervention in a pre-admission clinic context. Over 230 smokers received a brief smoking cessation intervention, while a control group (n = 114) received only a free Quit Kit. The age-standardised smoking prevalence was 19%; a further 3% of patients were recent quitters. Most smokers do not expect or experience problems with not smoking while in hospital. Brief smoking cessation advice tailored to stage-of-change by a health worker in a hospital pre-admission clinic significantly increased the quit rates for females.

Diurnal variation in the quantitative EEG in healthy adult volunteers

AIMS

To define the change in power in standard waveband frequencies of quantitative cortical electroencephalogram (EEG) data over a 24 h period, in a drug free representative healthy volunteer population.

METHODS

This was an open, non randomised study in which 18 volunteers (9 male and 9 female) were studied on 1 study day, over a 24 h period. Volunteers had a cortical EEG recording taken at 0, 2, 4, 6, 8, 10, 12, 16 and 24 h. Each recording lasted for 6 min (3 min eyes open, 3 min eyes closed). All EEG recordings were taken in a quietened ward environment with the curtains drawn round the bed and the volunteer supine. During the 3 min eyes open, volunteers were asked to look at a red circle on a screen at the foot of the bed, and refrain from talking.

RESULTS

Plots produced of geometric mean power by time of the standard wave band frequencies gave some indication of a circadian rhythm over the 24 h period for theta (4. 75-6.75 Hz), alpha1 (7.0-9.5 Hz) and beta1 (12.75-18.50 Hz) wavebands. Mixed models were fitted to both the eyes open and eyes closed data which confirmed a change in mean waveband power with time with statistical significance at the conventional 5% level (P < 0.05).

CONCLUSIONS

These data indicate the presence of a diurnal variation in the cortical quantitative EEG. They support the use of a placebo control group when designing clinical trials which utilize quantitative EEG to screen for central nervous system (CNS) activity of pharmaceutical agents, to control for the confounding variable of time of day at which the EEG recordings were made.

A community study of lower urinary tract symptoms in older men in Sydney, Australia

BACKGROUND

The aim of the present paper was to determine the prevalence, bother attributable to and self-reported management of uncomplicated lower urinary tract symptoms (LUTS) in men aged 40-80 years in Sydney, Australia.

METHODS

A total of 340 randomly selected men aged 40-80 years (65% response rate) participated in a community-based study (computer-assisted telephone survey).

RESULTS

Lower urinary tract symptoms are common: 54% of men needed to wake up at least once at night to urinate; 47% indicated they had terminal dribbling 'sometimes' or 'frequently'; 30% experienced urgency although few (4%) had urge incontinence; 21% experienced hesitancy; and 19% could retain urine in their bladder during the day for no more than 2 hours. Urinary symptoms correlated poorly with self-rated bother and there was no increase in age-specific prevalence of bothersome symptoms with increasing age. Only 37 (26%) men inconvenienced by urinary symptoms had seen a general practitioner (GP) about these symptoms in the last 5 years: of these, two-thirds had been referred to a urologist and half of these received surgical treatment. Independent predictors of attending a GP were increasing age (adjusted odds ratio (AOR) = 12.3; P = 0.0015); place of birth outside Australia (AOR = 3.8; P = 0.0036) and anxiety about prostate cancer (AOR = 2.6; P = 0.0318), but not the degree of worry due to urinary symptoms.

CONCLUSION

Lower urinary tract symptoms are common in men, but their experiences of bother correlate weakly with symptoms and do not appear to influence referral and treatment. Public and professional campaigns might increase wider understanding of the benefits of surgery for bothersome symptoms, not symptoms per se.

Community study of uncomplicated lower urinary tract symptoms among male Italien immigrants in Sydney, Australia

OBJECTIVE

To determine the prevalence, levels of bother and self-reported management of lower urinary tract symptoms (LUTS) in Italian-born men aged 40-80 years.

METHOD

305 randomly selected men aged 40-80 years (72% response rate) participated in a community-based study (computer-assisted telephone survey) in early 1997 in Sydney, Australia.

RESULTS

LUTS are common: 41% of men needed to wake up at least once at night to urinate; 35% indicated they had terminal dribbling 'sometimes' or 'frequently'; 31% experienced urgency although few (3%) had urge incontinence; 19% could retain urine in their bladder during the day for no more than 2 h, and 19% experienced hesitancy. Urinary symptoms correlated moderately/poorly with self-rated bother. The prevalence of bothersome frequency and urgency was significantly age-related. Only half (n = 49, 52%) of the men bothered by urinary symptoms had seen a general practitioner (GP) about these symptoms in the last 5 years: of these three quarters had been referred to a urologist and half of these had received surgical treatment. Anxiety about prostate cancer, but not the degree of bother from urinary symptoms, independently predicted attendance at a GP (adjusted odds ratio 6.4, p = 0.006).

CONCLUSIONS

Although LUTS are common in Italian-born men, their experiences of bother do not correlate well with symptoms and do not appear to influence referral and treatment. Education is needed to improve men's understanding of the importance of 'bother' as an indicator for urological surgery.

Smoking: rates and attitudes among nursing staff in central Sydney

The objectives of this study were to determine the prevalence and predictors of smoking and attitudes to smoking-related issues among nurses employed by the Central Sydney Area Health Service in Sydney, Australia. A self-administered questionnaire, was distributed via the internal mail system of the Central Sydney Area Health Service in November 1997 to 610 randomly selected nursing staff. Twenty-one per cent (n = 127) of respondents smoked. Smokers were significantly younger than non-smokers and were more likely to speak mainly English at home. There were clear differences between smokers and non-smokers in response to all attitude statements. Interventions specifically directed at nurses who smoke to assist them to stop and maintain cessation are indicated. Future health service workplace tobacco control programmes should address deficits in knowledge about the health effects of passive smoking, should raise awareness among nurses who smoke about their potential to affect the behaviours of others through modelling, and should provide all nurses with the skills required to be smoking educators and advocates for tobacco control.

Electroencephalographic and psychomotor effects of chlorpromazine and risperidone relative to placebo in normal healthy volunteers

AIMS

To investigate the effects of single oral doses of chlorpromazine (50 mg) and risperidone (2 mg) relative to placebo on topographical electroencephalometry (CATEEMTM ) and psychomotor tests in 12 healthy male volunteers.

METHODS

A double-blind, placebo-controlled, three-way crossover design using a double dummy blinding technique was utilized. Chlorpromazine was selected as representative of the 'typical' neuroleptics, being also highly sedative. Risperidone has been suggested as representative of the newer 'atypical' neuroleptics and is claimed to be only minimally sedative. Volunteers were dosed on 3 separate days with a minimum of 7 days interval between trial days. On each trial day volunteers were dosed twice. Dose 1 consisting of either chlorpromazine 50 mg or placebo to chlorpromazine, and dose 2 either risperidone 2 mg or placebo to risperidone. The volunteers were randomized so that each received either chlorpromazine or risperidone (or neither), but not both on an individual trial day. A 17 electrode quantitative topographical electroencephalograph (EEG) recording was taken for each volunteer before and after each dosing period. Seven psychomotor function tests were used to determine the effects of each treatment on psychomotor performance.

RESULTS

The data confirm the cited reports of sedation following single oral doses of chlorpromazine 50 mg. However, 7 of the 12 volunteers dosed with risperidone 2 mg also reported drowsiness/lethargy which was of greater severity and duration than 5 of the 12 volunteers who reported somnolence following dosing with chlorpromazine 50 mg. Objective assessment of psychomotor impairment using a short battery of psychomotor function tests mirrored the subjective reports of somnolence in that the impairment in volunteers dosed with risperidone 2 mg was greater in extent and magnitude than in volunteers dosed with chlorpromazine 50 mg. With respect to the cortical quantitative electroencephalogram, both chlorpromazine (50 mg) and risperidone (2 mg) increased power (4.75-6.75 Hz) in keeping with cited effects of other neuroleptics on the quantitative EEG. In addition, there was a statistically significant increase (P<0.05) in alpha1 (7.0-9.5 Hz) and beta1 (12.75-18.5 Hz) wavebands in volunteers dosed with risperidone 2 mg. Furthermore, based on estimates of variability, we propose that a 3 min eyes open and 3 min eyes closed quantitative EEG recording is sufficient to maintain adequate power for this technique, whilst allowing its application to early volunteer trials of novel neuroleptic agents.

CONCLUSIONS

This study demonstrates that quantitative EEG can be utilized in the profiling of neuroleptic agents, and could be readily applied to the early profiling of novel neuroleptics in limited numbers of volunteers, early in drug development. The chosen battery of psychomotor tests has clearly demonstrable sensitivity to the quantification of the subjective reports of somnolence secondary to both chlorpromazine and risperidone.

Effects of zolmitriptan (Zomig) on central serotonergic neurotransmission as assessed by active oddball auditory event-related potentials in volunteers without migraine

In this randomized, double-blind, three-period crossover trial, 24 healthy volunteers without migraine received zolmitriptan 5 mg, dexfenfluramine 15 mg or placebo orally. At 2, 6, and 24 h postdose, auditory stimuli of 1000 Hz (nontarget tone) and 2000 Hz (target tone) were randomly and binaurally presented in an active oddball paradigm (4:1 ratio). Cortical auditory evoked responses were recorded for 500 msec poststimulus. Plasma concentrations of zolmitriptan and a 17-lead quantitative EEG were assessed at the same timepoints. Relative to placebo, zolmitriptan reduced the maximum absolute amplitude, amplitude difference (from nontarget tone noise) and area under the curve of the cortical auditory target tone event-related potential (P300 ERP). The most dramatic effect of zolmitriptan was to diminish the point estimate of noise during the 200-400 msec poststimulus epoch. The effect of zolmitriptan appeared concentration dependent. The latency of the P300 ERP was unaffected by zolmitriptan and there was no clinically significant effect on the EEG. Modification by zolmitriptan of the cortical electrical activity evoked by auditory stimuli confirms a central action of this drug in humans, which appears to affect cortical information processing without global alteration of the quantitative EEG.

Effects of the antimigraine compound zolmitriptan ('Zomig') on psychomotor performance alone and in combination with diazepam in healthy volunteers

Zolmitriptan (Zomig) is a 5HT1B/1D agonist which has the ability to cross the intact blood-brain barrier to access central as well as peripheral receptors. Because of the potential for central nervous system side effects, this randomized, double-blind, placebo-controlled, 6-period crossover study evaluated the effects of 2.5 and 5 mg doses of zolmitriptan on psychomotor performance and investigated any pharmacodynamic or pharmacokinetic interaction with diazepam. Twelve healthy volunteers received the following "treatments" as single doses: zolmitriptan 2.5 mg, zolmitriptan 5 mg, diazepam 10 mg, zolmitriptan 2.5 mg + diazepam 10 mg, zolmitriptan 5 mg + diazepam 10 mg and placebo. Pre-dose and at 1, 4, 8, and 24 h post-dose, the following validated battery of psychomotor tests was performed: Bond-Lader visual analogue scales (calmness, contentedness, and alertness factors), critical flicker fusion test, choice reaction time (recognition, motor, and total reaction times), finger-tapping test, number cancellation test and digit symbol substitution test. Plasma concentrations of zolmitriptan, its active metabolite, and diazepam and its active metabolites were measured at the same timepoints. Zolmitriptan 2.5 and 5 mg had no effect on psychomotor function when given alone. In contrast, diazepam 10 mg had profound effects, consistent with its sedative properties, but there was no synergism on concomitant administration of either dose of zolmitriptan. Plasma concentrations of zolmitriptan, diazepam, and their respective active metabolites were similar when the two drugs were given alone or in combination.

Local implementation of national guidelines on lower urinary tract symptoms: what do general practitioners in Sydney, Australia suggest will work?

OBJECTIVES

Systematic reviews demonstrate that local initiatives are vital to implement nationally developed clinical practice guidelines. Evidence-based guidelines on the management of lower urinary tract symptoms in men were launched by the National Health and Medical Research Council in Sydney in April 1997. A study was conducted through interviews to establish patterns of care in the catchment area before the guidelines were implemented and general practitioners were surveyed in order to ascertain the most useful strategies for local implementation.

DESIGN

A four-page questionnaire asked respondents to rate nine items about guideline dissemination; six items relating to the marketing of the guidelines and 15 implementation strategics: conventional educational activities (six); innovative educational strategies (four); quality improvement approaches (two) and patient-based approaches (three).

SETTING

Sydney, Australia.

STUDY PARTICIPANTS

Eighty-three randomly selected general practitioners (50 males; 33 females).

RESULTS

Eighty-three out of 108 surveys were returned (77%). Respondents placed high value upon endorsement by eminent individuals and organizations other than the organization developing the guidelines; this was likely to gain their initial attention. One hundred per cent of respondents would be encouraged to use the guidelines if they were promoted as improving quality of care. Implementation strategies preferred by respondents included small group continuing education with a urologist and a general practitioner as a facilitator, lectures and patient education materials. Internet access, interactive computer systems, academic detailing' and distance education modules were of least interest.

CONCLUSIONS

Our method is feasible as a first step in planning local dissemination and implementation for national guidelines. While useful in identifying preferred strategies, its longer-term predictive validity for improving patient outcomes through better guideline implementation needs to be established.