Central sensitization in patients with non-cardiac chest pain: A clinical experimental study

Objective. Patients with non-cardiac chest pain (NNCP) suffer from unexplained and often intractable pain which can pose a major clinical problem. The aim of this study was to investigate nociceptive processing in NNCP patients and their response to experimentally acid-induced oesophageal hyperalgesia using a multimodal stimulation protocol. Material and methods. Ten highly selected patients with NCCP (mean age 43?years, 1?M) were compared with an age- and gender-matched group of 20 healthy subjects. After preconditioning, the distal oesophagus was painfully distended with a balloon using “impedance planimetry”. This method assesses the luminal cross-sectional area of the oesophagus based on the electrical impedance of the fluid inside the balloon. The baseline distensions were done before and after pharmacological relaxation of the smooth muscle with 20?mg butylscopolamine. After baseline distensions, a series of up to 10 mechanical stimuli was performed (temporal summation). The stimulations were repeated after sensitization of the oesophagus induced by acid perfusion. The sensory intensities were assessed during the stimulations and the referred pain area was mapped. Results. At baseline distensions, no differences were seen between patients and controls before and after relaxation of the smooth muscles. The patients tolerated fewer repeated distensions than controls (4.8±0.5 versus 9.1±0.9; p=0.04) and had an increased size of the referred pain areas to the mechanical stimulations (32.9±6.2 versus 64.9±18.3?cm²; p=0.01). After sensitization with acid, the patients developed hyperalgesia (p<0.001), whereas no significant changes were seen in controls. Conclusions. NCCP patients showed facilitated central pain mechanisms (temporal summation and visceral hyperalgesia after sensitization). This could be used in the diagnosis and understanding of the symptoms in these patients.     

Screening for overt thyroid disease in early pregnancy may be preferable to searching for small aberrations in thyroid function tests

Thyroid hormones are important regulators of foetal development, and in recent years, there has been much focus on the screening and treatment of pregnant women for even small aberrations in thyroid function tests. We searched PubMed for publications on thyroid function and pregnancy outcomes including child cognition, and included references from the retrieved articles. Both small aberrations in thyroid function tests in early pregnancy and an increase in risk of pregnancy complications may be caused by a functional change in the uteroplacental unit. Thus, the association found in several studies between small thyroid test abnormalities and pregnancy complications may be due to confounding, and thyroid hormone therapy will have no effect. On the other hand, screening of thyroid function in early pregnancy may identify 200–300 women with undiagnosed overt hypothyroidism per 100 000 pregnancies, which is at least five times more than the number of hypothyroid newborns identified by screening. A number of studies indicate that untreated overt thyroid disease in pregnancy may lead to complications. The potential benefit of screening and early therapy is supported by evidence, indicating that even severe maternal hypothyroidism does not lead to neurocognitive deficiencies in the child, if the condition is detected and treated during the first half of pregnancy. Screening and therapy for overt thyroid dysfunction in early pregnancy may be indicated, rather than focusing on identifying and treating small aberrations in thyroid function tests.     

Adoption of the chronic care model to improve HIV care: In a marginalized,largely aboriginal population

Objective

To measure the effectiveness of implementing the chronic care model (CCM) in improving HIV clinical outcomes.

Design

Multisite, prospective, interventional cohort study.

Setting

Two urban community health centres in Vancouver and Prince George, BC.

Participants

Two hundred sixty-nine HIV-positive patients (18 years of age or older) who received primary care at either of the study sites.

Intervention

Systematic implementation of the CCM during an 18-month period.

Main outcome measures

Documented pneumococcal vaccination, documented syphilis screening, documented tuberculosis screening, antiretroviral treatment (ART) status, ART status with undetectable viral load, CD4 cell count of less than 200 cells/mL, and CD4 cell count of less than 200 cells/mL while not taking ART compared during a 36-month period.

Results

Overall, 35% of participants were women and 59% were aboriginal persons. The mean age was 45 years and most participants had a history of injection drug use that was the presumed route of HIV transmission. During the study follow-up period, 39 people died, and 11 transferred to alternate care providers. Compared with their baseline clinical status, study participants showed statistically significant (P < .001 for all) increases in pneumococcal immunization (54% vs 84%), syphilis screening (56% vs 91%), tuberculosis screening (23% vs 38%), and antiretroviral uptake (47% vs 77%), as well as increased viral load suppression rates among those receiving ART (72% vs 90%). Stable housing at baseline was associated with a 4-fold increased probability of survival. Aboriginal ethnicity was not associated with better or worse outcomes at baseline or at follow-up.

Conclusion

Application of the CCM approach to HIV care in a marginalized, largely aboriginal patient population led to improved disease screening, immunization, ART uptake, and virologic suppression rates. In addition to addressing underlying social determinants of health, a paradigm shift away from an “infectious disease” approach to a “chronic disease management” approach to HIV care for marginalized populations is strongly recommended.     

Staphylococcus aureus and influenza A virus stimulate human bronchoalveolar cells to release histamine and leukotrienes

Mediator release was examined from superficially lying cells in the airway epithelium obtained by bronchoalveolar lavage (BAL) in 13 non-atopic individuals. The BAL-cells were incubated (20 min, 37 degrees C) with Staphylococcus (Staph.) aureus or with human influenza A virus Staph. aureus was found to release histamine from cells from 7 of the 13 individuals and influenza A virus in 3 of 5 persons. Furthermore, Staph, aureus stimulated the BAL-cells to release leukotriene B4 in 7 of 11 subjects, whereas no release was found by influenza A virus in 7 examined persons. When cells from 4 persons were stimulated with Staph. aureus no release of leukotriene C4 was found. The mediator release caused by bacteria and virus might be of importance for the exacerbation of bronchial asthma in upper respiratory tract infections, since histamine is assumed to increase the epithelial permeability with entrance of allergens and other insulting particles, and leukotriene B4 facilitates airway inflammation.     

Role modelling and cigarette smoking: vulnerable working class girls? A longitudinal study.

Risk factors for the onset of cigarette smoking were examined by means of a prospective longitudinal study in 1230 Norwegian adolescents aged 12-18. In particular the importance of role modelling was focused. The findings revealed that the age period between 12 and 15 is most important when it comes to the initiation of smoking. Among those who initiate smoking, the incidence rates of quitting is low, indicating that most of the initiators quickly seem to develop a relatively stable smoking habit. Smoking initiation can be divided into two stages. The first, experimental one, is predicted by peer modelling and low socioeconomic status (SES). The second, establishing a regular pattern of use, is predicted by modelling of parental smoking and the interaction between female sex and low SES. Studying the characteristics of the regular smokers cross-sectionally, peer modeling showed the strongest correlates. Studying the predictors of the transitions longitudinally, the more complex picture described above was uncovered. This indicates that the complexity of the role modelling process can only be simulated adequately by means of prospective research methods and by paying attention to such parameters as gender, age, SES and stage in the smoking acquisition process.     

Immune parameters in male atheletes after a lacto-ovo vegetarian diet and a mixed Western diet

The influence of a lacto-ovo vegetarian diet versus a meat-rich Western diet on in vitro measures of immune function was studied in eight male endurance athletes. Subjects consumed two different diets for 2 x 6 wk, separated by 4 wk on an ad libitum diet, in a cross-over design. Both diets consisted of 57 energy % (E%) carbohydrates, 14 E% protein and 29 E% fat. One diet was a mixed meat-rich diet (M) prepared with 69% animal protein sources, whereas the other diet (V) was a lacto-ovo vegetarian diet prepared with 82% vegetable protein sources. Blood for determination of leukocyte subpopulations and in vitro function was collected at the end of each diet period 36 h after the last training bout. Fiber content and P/S ratio of fatty acids were twice as high on the V diet as on the M diet. Training volume was similar on the two diets, and maximal aerobic capacity did not change during diet periods. The number of CD3+ (pan T-cells), CD8+ (mainly T suppressor cells), CD4+ (mainly T helper cells), CD16+ (natural killer cells), and CD14+ (monocytes) was similar after the two different diets. Similarly, proliferations of mononuclear cells after stimulation with interleukin-2 (IL-2), phytohemagglutinin, and purified derivative of tuberculin (PPD), as well as activity of natural killer cells in the unstimulated state and after stimulation with IL-2, indomethacin, and interferon-alpha (IFN-alpha), were identical after the two diet periods.(ABSTRACT TRUNCATED AT 250 WORDS)