Time Dependence of Whole Blood Aggregation in Response to Platelet Activating Factor (PAF)

The aggregation/adhesion response to platelet activating factor (PAF) was studied in diluted whole blood by impedance aggregometry. The extent of aggregation varied directly with the interval between blood sampling and aggregation measurement over the first 30 minutes from sampling, then remained stable for the next 60 minutes of observation. This is an effect opposite to that described for aggregation to PAF in platelet rich plasma which, however, cannot be studied soon after sampling. Time dependence of aggregation is important and comparative measurements should be made during the period of stable aggregability.

Inner ear tissue preservation by rapid freezing: improving fixation by high-pressure freezing and hybrid methods

In the preservation of tissues in as ‘close to life’ state as possible, rapid freeze fixation has many benefits over conventional chemical fixation. One technique by which rapid freeze-fixation can be achieved, high pressure freezing (HPF), has been shown to enable ice crystal artefact-free freezing and tissue preservation to greater depths (more than 40 μm) than other quick-freezing methods. Despite increasingly becoming routine in electron microscopy, the use of HPF for the fixation of inner ear tissue has been limited. Assessment of the quality of preservation showed routine HPF techniques were suitable for preparation of inner ear tissues in a variety of species. Good preservation throughout the depth of sensory epithelia was achievable. Comparison to chemically fixed tissue indicated that fresh frozen preparations exhibited overall superior structural preservation of cells. However, HPF fixation caused characteristic artefacts in stereocilia that suggested poor quality freezing of the actin bundles. The hybrid technique of pre-fixation and high pressure freezing was shown to produce cellular preservation throughout the tissue, similar to that seen in HPF alone. Pre-fixation HPF produced consistent high quality preservation of stereociliary actin bundles. Optimising the preparation of samples with minimal artefact formation allows analysis of the links between ultrastructure and function in inner ear tissues.

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Routine high pressure freezing can preserve large depths of inner ear tissue.

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Stereocilial actin preserved by rapid freezing exhibits characteristic artefacts.

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Hybrid methods of fixation improved structural preservation of stereocilial actin.

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Improved fixation will reduce artefacts in ultrastructural studies of the inner ear.

Quantitative proteomics in laser capture microdissected sleep nuclei from rat brain

The combination of stable isotope labeling of amino acids in mammals (SILAM) and laser capture microdissection (LCM) for selective proteomic analysis of the targeted tissues holds tremendous potential for refined characterization of proteome changes within complex tissues such as the brain. The authors have applied this approach to measure changes in relative protein abundance in ventral tegmental area (VTA) of the rat brain that correlate to pharmacological perturbations. Enriched ¹³C₆¹⁵N₂-lysine was introduced in vivo via diet. These animals were sacrificed during the middle of the 12-hour light period to extract isotopically “heavy” proteins, which were then used as a reference for extracts from dosed, unlabeled rats. Animals were administered an orexin peptide (Ox-B), an orexin receptor antagonist (ORA), or a mixture of both (Ox-B + ORA). All samples were obtained at same phase of the sleep cycle. Labeled-pair identification and differential quantitation provided protein identification and expression ratio data. Five proteins were found to exhibit decreased relative abundance after administration of an ORA, including α-synuclein and rat myelin basic protein. Conversely, six proteins showed increased relative abundance upon antagonist treatment, including 2’,3’-cyclic nucleotide 3’-phosphodiesterase.

Costs and outcomes over 36 years of patients with phenylketonuria who do and do not remain on a phenylalanine-restricted diet

BACKGROUND

To quantify the costs and consequences of managing phenylketonuria (PKU) in the UK and to estimate the potential implications to the UK's National Health Service (NHS) of keeping patients on a phenylalanine-restricted diet for life.

METHOD

A computer-based model was constructed depicting the management of PKU patients over the first 36 years of their life, derived from patients suffering from this metabolic disorder in The Health Improvement Network database (a nationally representative database of patients registered with general practitioners in the UK). The model was used to estimate the incidence of co-morbidities and the levels of healthcare resource use and corresponding costs over the 36 years.

RESULTS

Patients who remained on a phenylalanine-restricted diet accounted for 38% of the cohort. Forty-seven per cent of patients discontinued their phenylalanine-restricted diet between 15 and 25 years of age. Of these, 73% remained off diet and 27% restarted a restricted diet at a mean 30 years of age. Fifteen per cent of the cohort had untreated PKU. Eleven per cent of patients who remained on a phenylalanine-restricted diet for 36 years received the optimum amount of prescribed amino acid supplements. Patients had a mean 12 general practitioner visits per year and one hospital outpatient visit annually, but phenylalanine levels were only measured once every 18 to 24 months. The mean NHS cost (at 2007/08 prices) of managing a PKU sufferer over the first 36 years of their life was estimated to range between £21 000 and £149 000, depending on the amount of prescribed nutrition they received.

CONCLUSION

The findings suggest that the majority of patients with PKU were under-treated. The NHS cost of patient management should not be an obstacle to encouraging patients to remain on a restricted diet until further information becomes available about the long-term clinical impact of stopping such a diet. Nevertheless, patients require counselling and managed follow up regardless of the choices they make about their diet.

Attitudes regarding chronic fatigue syndrome: the importance of a name

Undergraduates from diverse academic backgrounds and medical trainees were assessed regarding their attitudes about and familiarity with chronic fatigue syndrome (CFS). We explored whether different names given to chronic fatigue syndrome (CFS, myalgic encephalopathy, or Florence Nightingale disease) were associated with differences in attributions regarding its cause, nature, severity, contagion, prognosis, and treatment. Participants' attributions toward the illness varied with the names used to characterize it. Participants prompted with the myalgic encephalopathy name were more likely to attribute a biomedical cause to the illness, and less likely to consider patients as candidates for organ donation than those prompted with the CFS name. Although the medical trainees were less likely to consider the patient as malingering, and more likely to view the illness as leading to poorer quality of life and a poorer prognosis, they were also more likely to consider the illness a form of primary depression, more likely to think the patient would attempt suicide, and less likely to consider associated cognitive symptoms as severe. The implications are discussed.

Modelling the cost-effectiveness of electric stimulation therapy in non-healing venous leg ulcers

OBJECTIVE

To estimate the cost-effectiveness of using electric stimulation (ES) therapy (Accel-Heal) plus dressings and compression bandaging compared with dressings and compression bandaging alone in treating chronic, non-healing venous leg ulcers (VLUs) of >6 months' duration from the perspective of the National Health Service (NHS) in the UK.

METHOD

A 5-month Markov model was constructed, depicting the management of a chronic, non-healing VLU of >6 months' duration. The model considers the decision by a clinician to continue with a patient's previous care plan (comprising dressings and compression bandaging) or treating with ES therapy plus dressings and compression bandaging. The model was used to estimate the relative cost-effectiveness of ES therapy at 2008-2009 prices.

RESULTS

According to the model, 38% of VLUs are expected to heal within 5 months after starting ES therapy, with a further 57% expected to improve. This improvement in clinical outcome is expected to lead to a 6% health gain of 0.017 QALYs (from 0.299 to 0.316 QALYs) over 5 months. The model also showed that using ES therapy instead of continuing with a patient's previous care plan is expected to reduce the NHS cost of managing them by 15%, from £880 to £749, due in part to a 27% reduction in the requirement for nurse visits (from mean 49.0 to 35.9 visits per patient) over the first 5 months after the start of treatment. Hence, use of ES therapy was found to be a dominant treatment (improved outcome for less cost).

CONCLUSION

Within the model's limitations, use of ES therapy potentially affords the NHS a cost-effective treatment, compared with patients remaining on their previous care plan in managing chronic, non-healing VLUs of >6 months' duration. However, this is dependant on the number of ES therapy units per treatment, the unit cost of the device, and the number of nurse visits required to manage patients in clinical practice.

DECLARATION OF INTEREST

This study was sponsored by Synapse Microcurrent Ltd., manufacturers of Accel-Heal. The authors have no other conflicts of interest that are directly relevant to the content of this manuscript. In particular, Synapse Microcurrent Ltd. had no role in the study design, in the collection, analysis and interpretation of data, or in writing the manuscript.

The cost-effectiveness of macrogol 3350 compared to lactulose in the treatment of adults suffering from chronic constipation in the UK

BACKGROUND

It is unknown whether macrogol 3350 (Movicol) affords the UK's National Health Service (NHS) a cost-effective addition to the current range of laxatives.

AIM

To estimate the cost-effectiveness of macrogol 3350 compared with lactulose in the treatment of chronic constipation, from the perspective of the UK's NHS.

METHODS

A decision model depicting the management of chronic constipation was constructed using clinical outcomes and resource use values derived from patients suffering from chronic constipation in The Health Independent Network (THIN) database. The model was used to estimate the cost-effectiveness of a GP prescribing macrogol 3350 instead of lactulose to treat adults > or =18 years of age suffering from chronic constipation.

RESULTS

Sixty-eight percent of patients given macrogol 3350 were successfully treated within 6 months after starting treatment compared to 60% of patients given lactulose.Patients' health status at 6 months was estimated to be 0.458 and 0.454 quality-adjusted life years (QALYs) in the macrogol 3350 and lactulose groups respectively. The total 6-monthly NHS cost of initially treating patients with macrogol 3350 or lactulose was estimated to be pound420 (US $688) and pound419 (US $686) respectively. Hence, the cost per QALY gained with macrogol 3350 was estimated to be pound250 (US $410).

CONCLUSION

Macrogol 3350 affords the NHS a cost-effective addition to the range of laxatives available for this potentially resource-intensive condition.

Refined anatomical isolation of functional sleep circuits exhibits distinctive regional and circadian gene transcriptional profiles

Powerful new approaches to study molecular variation in distinct neuronal populations have recently been developed enabling a more precise investigation of the control of neural circuits involved in complex behaviors such as wake and sleep. We applied laser capture microdissection (LCM) to isolate precise brain nuclei from rat CNS at opposing circadian time points associated with wake and sleep. Discrete anatomical and temporal analysis was performed to examine the extent of variation in the transcriptional control associated with both identifiable anatomical nuclei and with light/dark cycle. Precise isolation of specific brain nuclei regulating sleep and arousal, including the LC, SCN, TMN, VTA, and VLPO, demonstrated robust changes in gene expression. Many of these differences were not observed in previous studies where whole brain lysates or gross dissections were used to probe for changes in gene expression. The robust and differential profiles of genomic data obtained from the approaches used herein underscore the requirement for careful anatomical refinement in CNS gene expression studies designed to understand genomic control within behaviorally-linked, but functionally isolated brain nuclei.

Efficacy of the latest fluoroquinolones against experimental Yersinia pestis

The efficacies of prophylactic and therapeutic gatifloxacin and moxifloxacin were assessed in a BALB/c mouse model of systemic and pneumonic plague and compared with ciprofloxacin. Mice were given 100 mg/kg of the antibiotic by oral administration twice daily for 7 days starting 1h prior to infection or following infection. All antibiotics offered full protection for up to 6h following systemic challenge, and for up to 30 h following an aerosol challenge. The efficacy of each of the antibiotics decreased when antibiotics were started 18 h following systemic challenge and 48 h following aerosol challenge. Fluoroquinolones may therefore be considered useful candidates for the treatment of bubonic and pneumonic plague.

Developmental analysis and computer modelling of bioengineered teeth

Here we present the developmental progression of bioengineered pig teeth from 1 to 25 weeks of development. We demonstrate that 2-25 week implants contained embryonic tooth bud- and cap-stage tooth structures consisting of dental epithelium expressing the sonic hedgehog gene and condensed dental mesenchyme. Implants harvested at 18-25 weeks also contained tooth bud-like structures, as well as mature tooth structures containing enamel, dentin and pulp tissues. Immunohistochemical analyses confirmed the expression of dentin- and enamel-specific proteins in differentiated bioengineered tooth tissues. Three-dimensional computer modelling further demonstrated a spatial organization of enamel, dentin and pulp tissues resembling that of natural teeth. We conclude that bioengineered teeth commonly exhibit morphological stages characteristic of naturally forming teeth. Furthermore, the presence of immature tooth buds at all times assayed and increased numbers of bioengineered tooth structures over time suggests that porcine dental progenitor cells maintain the ability to form teeth for at least 25 weeks.

Symptom occurrence in persons with chronic fatigue syndrome

This investigation compared differences in the occurrence of symptoms in participants with CFS, melancholic depression, and no fatigue (controls). The following Fukuda et al. [Ann. Intern. Med. 121 (1994) 953] criteria symptoms differentiated the CFS group from controls, but did not differentiate the melancholic depression group from controls: headaches, lymph node pain, sore throat, joint pain, and muscle pain. In addition, participants with CFS uniquely differed from controls in the occurrence of muscle weakness at multiple sites as well as in the occurrence of various cardiopulmonary, neurological, and other symptoms not currently included in the current case definition. Implications of these findings are discussed.

Assessing attitudes toward new names for chronic fatigue syndrome

A questionnaire was distributed at the American Association of Chronic Fatigue Syndrome's biannual convention in Washington in January 2001 as well as through various Internet Web sites and listserves during early February and March of 2001. The sample consisted of 432 respondents. Most respondents (86%) indicated they wanted a name change, although more patients than scientists were in favor of this change. It was also apparent that the patients and physicians were clearly split between adopting a name such as myalgic encephalopathy versus one such as neuro-endocrine immune disorder. Also, among those respondents who selected either of these two choices for a new name, less than 30% of them supported the other name. Although the majority of respondents feel the name should be changed at this time, this survey suggests there are different stakeholders involved in the name-change process, each with strong and sometimes disparate feelings about changing the name.

Sexual abuse, physical abuse, chronic fatigue, and chronic fatigue syndrome: a community-based study

Using a randomly selected community-based sample, this investigation examined whether histories of childhood sexual, physical, and death threat abuse predicted adulthood outcomes of specific medical and psychiatric conditions involving chronic fatigue. This study also tested prior suggestions that most individuals with chronic fatigue syndrome report a past history of interpersonal abuse. Multinomial logistic regression was used to examine the relationship between abuse history and chronic fatigue group outcomes while controlling for the effects of sociodemographics. Compared with healthy controls, childhood sexual abuse was significantly more likely to be associated with outcomes of idiopathic chronic fatigue, chronic fatigue explained by a psychiatric condition, and chronic fatigue explained by a medical condition. None of the abuse history types were significant predictors of chronic fatigue syndrome. A closer examination of individuals in the chronic fatigue syndrome group revealed that significantly fewer individuals with CFS reported abuse as compared with those who did not. The implications of these findings are discussed.

Improved analysis of brachial artery ultrasound using a novel edge-detection software system

Brachial artery ultrasound is commonly employed for noninvasive assessment of endothelial function. However, analysis is observer dependent and susceptible to errors. We describe studies on a computerized edge-detection and wall-tracking software program to allow more accurate and reproducible measurement. In study 1, three purpose-built Perspex phantom arteries, 3.00, 4.00, and 6.00 mm in diameter, were measured with the software. There was a mean bias of 11 microm (P < 0.001 at each level) between known and measured values; the mean resolving power of the software was estimated as 8.3 microm. In study 2, the mean intraobserver coefficient of variation of repeated measures of flow-mediated dilation (FMD) using the software (6.7%) was significantly lower than that for traditional manual measurements using the intima-lumen interfaces (24.8%, P < 0.05) and intima-media interfaces (32.5%, P < 0.05). In study 3, 24 healthy volunteers underwent repeat testing twice within 1 wk; the coefficients of variation for between-visit reproducibility of FMD and response to glyceryl trinitrate using the software were 14.7 and 17.6%, respectively. Assuming 80% power and an alpha of 0.05, eight subjects with matched controls would be required, in a parallel designed study, to detect an absolute 2.5% change in FMD. In summary, we have developed a semiautomated computerized vascular ultrasound analysis system that will improve the power of clinical intervention studies to detect small changes in arterial diameter.

Lack of evidence for association between endothelial nitric oxide synthase gene polymorphisms and coronary artery disease in the Australian Caucasian population

BACKGROUND

Genetic polymorphism in the gene for endothelial nitric oxide synthase (eNOS) has been identified as a potential risk factor for the development of premature coronary artery disease (CAD). We determined whether the eNOS 4ab, G894T, and T-786C polymorphisms are associated with premature coronary artery disease.

DESIGN

A case-control study.

METHODS

PCR-based assays were used to compare the frequency of eNOS gene polymorphisms in 573 Caucasian subjects aged under 50 years presenting with symptomatic CAD and documented by coronary angiography, with or without myocardial infarction, to that of 624 similarly aged community controls without a history of symptomatic CAD.

RESULTS

We found no difference in the frequency of 4ab genotypes between cases and controls: in the CAD subjects, the 4aa, 4ab, and 4bb genotype frequencies were 1.9%, 24.3% and 73.8% respectively, compared to 2.2%, 25.5% and 72.3% respectively for the controls. There was also no significant difference between cases and controls in the frequency of any allele (4a/4b, 894G/894T, -786C/-786T), or genotype for any of the polymorphisms. Similarly, logistic regression analysis showed no evidence for an association of the polymorphisms with premature CAD or myocardial infarction or any indication of an interaction between the polymorphisms and other CAD risk factors, including smoking.

CONCLUSIONS

In a large case-control study, and in contrast to some earlier positive findings by others, we have found no evidence for an association between several eNOS gene polymorphisms and premature CAD in an Australian Caucasian population.

A community-based study of seasonal variation in the onset of chronic fatigue syndrome and idiopathic chronic fatigue

One proposed hypothesis regarding the etiology of chronic fatigue syndrome (CFS) is that there is a subgroup of patients in which symptom onset is precipitated by a viral infection. If this is indeed true, then one would anticipate a greater incidence of the emergence of CFS symptoms during months when viral infections occur with the greatest frequency. The current community-based epidemiology study examined the month of symptom onset for 31 patients with CFS and 44 others with idiopathic chronic fatigue (ICF). It was determined that the distribution of the month of illness onset for the CFS and ICF groups was nonrandom, with greater numbers of participants than expected reporting an onset of CFS and ICF during January.

Equal care ensures equal survival for African-American women with cervical carcinoma

BACKGROUND

[corrected] It was the purpose of this study to investigate whether race is an independent prognostic factor in the survival of patients with cervical carcinoma in a health care system with minimal racial bias, and few barriers to access to care.

METHODS

Records for patients with a diagnosis of invasive cervical carcinoma from 1988 to 1999 were obtained from the Automated Central Tumor Registry for the United States Military Health Care System. Clinical data including race, age at diagnosis, histology, grade, stage, socioeconomic status, treatment modality, and survival also were obtained. Survival analysis was performed with Kaplan-Meier survival curves.

RESULTS

One thousand five hundred fifty-three patients were obtained for review. Sixty-five percent of patients were Caucasian, and 35% were minorities. Of the minorities, 29% were African Americans (AAs). Mean age of diagnosis was similar among AAs and Caucasians, 44 and 42 years, respectively. There was no statistically significant difference between the distribution of age, stage, grade, or histology between Caucasians and AAs. Forty-six percent of patients were treated with surgery and 56% with radiation therapy, with no difference in type of treatment between the Caucasian and AA groups. Five- and 10-year survival rates for Caucasians and AAs were 75%, and 76%, and 64% 65% (P = 0.59), respectively.

CONCLUSIONS

In an equal access, unbiased, nonracial environment, race is not an independent predictor of survival for patients with cervical carcinoma. This study has shown, for the first time to the authors' knowledge, that when they receive equal treatment for cervical carcinoma, AA women's survival can approach that of their nonminority counterparts (75% at 10 years).

Chronic fatigue syndrome: an examination of the phases

The present study examined the Fennell Phase Inventory, an instrument designed to measure the phases typically experienced by individuals with chronic fatigue syndrome (CFS). This inventory yields three factor scores of Crisis, Stabilization, and Integration. These factor scores have been employed in a cluster analysis, yielding four clusters that matched the four phases predicted by Fennell: Crisis, Stabilization, Resolution, and Integration. The present study represents a partial replication study of a prior investigation of the Fennell Phase Inventory by Jason et al. (in press), but that earlier study did not have an independent physician examination to diagnose patients with CFS. In the present study, 65 patients diagnosed with chronic fatigue syndrome by a physician were recruited and administered the Fennell Phase Inventory and other measures assessing CFS-related symptoms, disability, and coping. Each of the 65 patients was classified into one of four predefined clusters measuring a Crisis phase, a Stabilization phase, a Resolution phase, and an Integration phase. Relationships were explored between three of these cluster groupings and measures of symptoms, disability, and coping. Results confirmed Fennell's model, revealing significant differences between the three clusters in terms of levels of disability and modes of coping. Results suggest that the Fennell Phase Inventory accurately differentiates phases of adaptation to illness experienced by individuals with CFS.

Age-specific survival of women with endometrioid adenocarcinoma of the uterus

OBJECTIVE

The purpose of this paper was to evaluate the age-specific survival for women diagnosed with endometrioid adenocarcinoma of the uterus.

METHODS

A retrospective analysis was conducted of 328 patients diagnosed with endometrioid adenocarcinoma of the uterus between January 1990 and December 1997. Patients were followed for 3 to 96 months with a mean of 43 months. The impact of age on survival was assessed using Cox proportional hazard regression and multivariate analysis for age, stage, and grade. Stage and grade were analyzed using log-rank tests, and survival curves were generated by the Kaplan-Meier method.

RESULTS

A total of 328 patients were evaluated. Multivariate analysis revealed age, stage, and grade were all significant independent predictors of survival (P < 0.0001). Age-specific survival varied from a high of 90% at age 40 to a low of 55% at age 80. Interval age-specific survival decreased below 86% at age 50. Subset analysis of patients younger than 50 compared with older patients revealed no difference in surgical stage or grade of tumors among these patients. Patients older than 50, however, were 41% more likely to receive adjuvant radiation therapy.

CONCLUSION

Age is a specific, significant predictor of outcome in endometrioid adenocarcinoma of the uterus. Survival decreases significantly in patients older than 50. This decreased survival associated with age is unrelated to surgical stage or grade of adenocarcinoma. Decreased survival could involve molecular differences in the developing endometrial cancer or an increased risk of death from other non-cancer-related factors.

Chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities in a community-based sample of persons with chronic fatigue syndrome-like symptoms

OBJECTIVE

The aim of this study was to determine illness comorbidity rates for individuals with chronic fatigue syndrome (CFS), fibromyalgia (FM), and multiple chemical sensitivities (MCS). An additional objective was to identify characteristics related to the severity of fatigue, disability, and psychiatric comorbidity in each of these illness groups.

METHODS

A random sample of 18,675 residents in Chicago, Illinois, was first interviewed by telephone. A control group and a group of individuals with chronic fatigue accompanied by at least four minor symptoms associated with CFS received medical and psychiatric examinations.

RESULTS

Of the 32 individuals with CFS, 40.6% met criteria for MCS and 15.6% met criteria for FM. Individuals with MCS or more than one diagnosis reported more physical fatigue than those with no diagnosis. Individuals with more than one diagnosis also reported greater mental fatigue and were less likely to be working than those with no diagnosis. Individuals with CFS, MCS, FM, or more than one diagnosis reported greater disability than those with no diagnosis.

CONCLUSIONS

Rates of coexisting disorders were lower than those reported in prior studies. Discrepancies may be in part attributable to differences in sampling procedures. People with CFS, MCS, or FM endure significant disability in terms of physical, occupational, and social functioning, and those with more than one of these diagnoses also report greater severity of physical and mental fatigue. The findings illustrate differences among the illness groups in the range of functional impairment experienced.

Angiotensin-converting enzyme gene polymorphism and premature coronary heart disease

Since the initial report of the association of the deletion/insertion (D/I) polymorphism in the gene for angiotensin-converting enzyme (ACE) with myocardial infarction (MI), there has been considerable controversy. Some have found the D allele to be associated with MI, coronary heart disease (CHD) or other cardiac pathology, while others have not. In the present study 713 consecutive patients, < 50 years of age, documented prospectively with angiographic CHD (> 50% diameter stenosis of at least one coronary artery), with or without MI, were studied, along with 688 community control subjects, also < 50 years of age, selected randomly from the electoral rolls and without a history of CHD or MI. Genotyping was done by standard methods. Most of the subjects in both groups were Anglo-Celtic Caucasians (547 in the CHD group and 642 in the community group), and the report concerns primarily these subjects. ACE genotype distributions were not different between the Caucasian community control group and the CHD or the MI subgroups; the odds ratios and 95% confidence limits for the CHD group were 0.96 (0.73-1.27) for the D allele and 1.02 (0.80-1.31) for D homozygotes; for the MI group these values were 1.00 (0.83-1.20) and 0.99 (0.74-1.32) respectively. This negative result was supported in multivariate analysis accounting for conventional risk factors. There was a significant racial difference in ACE genotypes between Caucasians, Asians and Australian Aborigines in the CHD group (P < 0.001); for example, in this group, 158 of 540 (29%) Caucasians had the DD genotype compared with eight of 84 (10%) Aboriginals (P < 0.001) and six of 59 (10%) Asians (P = 0.002). Failure to account for such racial differences would have led to erroneous conclusions. In conclusion, we found no evidence that the D/I ACE gene polymorphism plays a role in the development of CHD or MI at an early age in a Western Australian Caucasian population. While this result refers uniquely to premature CHD and MI, and could be population specific, it is in general agreement with recent meta-analysis of the larger previous studies.

Chronic fatigue syndrome: sociodemographic subtypes in a community-based sample

Most chronic fatigue syndrome (CFS) studies are based on information about patients from primary or tertiary care settings. These patients might not be typical of patients in the general population. This investigation involved examinations of individuals with CFS from a community-based study. A random sample of 18,675 in Chicago was interviewed by telephone. Individuals with chronic fatigue and at least four minor symptoms associated with CFS were given medical and psychiatric examinations. A group of physicians then diagnosed individuals with CFS, who were then subclassified based on three sociodemographic categories--gender, ethnicity, and work status. Sociodemographic subgroups were analyzed in terms of symptom severity, functional disability, coping, optimism, perceived stress, and psychiatric comorbidity. Women, minorities, and nonworking individuals with CFS reported greater levels of functional disability, symptom severity, and poorer psychosocial functioning than men, Caucasians, and working individuals, suggesting sociodemographic characteristics may be associated with poorer outcomes in urban, community-based samples of CFS individuals.

Chronic fatigue syndrome: occupation, medical utilization, and subtypes in a community-based sample

Most studies of chronic fatigue syndrome (CFS) have been based on patients recruited from primary or tertiary care settings. Patients from such settings might not be typical of patients in the general population. The present investigation involved examining individuals with CFS from a community-based study. A random sample of 18,675 respondents in Chicago was first interviewed by telephone. A group of individuals with chronic fatigue accompanied by at least four minor symptoms associated with CFS were given medical and psychiatric examinations. From this sample, a physician review group diagnosed individuals with CFS. Those diagnosed with CFS were subclassified based on a variety of categories, including duration of illness, mode of illness onset, and presence or absence of a stressful life event directly preceding onset. In addition, we examined medical utilization among those diagnosed with CFS, as well as whether individuals with CFS were disproportionately represented in health care professions. Important differences emerged on measures of sociodemographics, symptoms, and functional disability. The implications of these findings and others are discussed.