Prevalence of Chronic Bronchitis and Respiratory Health Profile of a Population Exposed to Wood Smoke in Nicaragua.

BACKGROUND: Household air pollution (HAP) is one of the most important environmental risk factors worldwide associated with chronic respiratory diseases. OBJECTIVES: The present study focused on respiratory health in a population with high wood smoke exposure in Nicaragua. METHODS: We employed a cross-sectional study with 213 participants. Data on the prevalence of chronic bronchitis (chronic bronchitis), chronic obstructive pulmonary disease (COPD) and asthma, including respiratory scores and pulmonary function tests, were documented. The role of risk factors for chronic bronchitis was analyzed. RESULTS: We found a high prevalence of chronic airway diseases in the population exposed to wood smoke. A higher prevalence of chronic bronchitis was found in persons serving as primary cooks in households. Further confounding factors for chronic bronchitis included age, a prior diagnosis of asthma, inhalational allergies and lower socioeconomic status. Respiratory scores were elevated in individuals with chronic bronchitis. CONCLUSIONS: This is one of the first studies in a wood smoke-exposed population in Nicaragua showing a high prevalence of chronic bronchitis and COPD with an emphasis on the analysis of personal and environmental risk factors. Further studies are needed to address which combination of interventions is most efficient for ameliorating respiratory health hazards. PARTICIPANT CONSENT: Obtained. ETHICS APPROVAL: The study protocol was approved by the Ethics Committee of the University of Luebeck, Germany (reference number 12-214), and by the Ethics Committee of the Department of Medical Sciences at National Autonomous University of Nicaragua, Managua, Nicaragua. COMPETING INTERESTS: The authors declare no competing financial interests.

Positive impact of improved cookstove usage on respiratory health in Congolese refugees: a prospective cohort study.

Around 3 billion people worldwide use solid biomass fuels for cooking. Exposure to indoor biomass smoke is an important cause of COPD and therefore a target of many public health interventions, such as usage of improved cookstoves. The aim of our study was to show whether usage of improved cookstoves can lead to relevant improvement in lung function and CAT-score in a well characterized population including a subgroup of this population with preexisting airway obstruction. Interviews and spirometry were performed in Congolese women living in an UNHCR (United Nations High Commissioner for Refugees) refugee camp in Rwanda before (baseline, BL) and 9 months after (follow-up, F9) they received an energy-efficient cookstove (Save80) and were trained how to use it. Two hundred sixty-two women completed both spirometry and interview appropriately at BL and F9 and were included in per protocol (pp) analysis, which showed no change in mean FEV1. The predefined subgroup of this population with airway obstruction at baseline (N = 31) showed a significant FEV1 increase (FEV1F9 = 1.70 L; p < 0.01 vs FEV1BL = 1.58 L, p < 0.01). Median CAT-scores were significantly lower in the F9 assessment. Our data indicate that usage of improved cookstoves has a positive impact on respiratory health especially in individuals with preexisting airway obstruction. Further studies to investigate long-term outcome are warranted.

Central sleep apnea is associated with blunted baroreflex sensitivity in patients with myocardial infarction.

OBJECTIVES: The purpose of this study was to investigate the association of central sleep apnea (CSA) and baroreflex sensitivity (BRS) after acute myocardial infarction. BACKGROUND: Both, CSA and blunted BRS have been shown to be independent predictors for cardiovascular mortality in patients with heart failure. But in contrast to BRS, which has been extensively studied in the setting of AMI, the incidence of CSA in patients recovering from AMI is thus far unknown. As previous reports suggested a potential role of sleep apnoea in augmenting reflex autonomic modulation, we hypothesized that there is a strong interrelation between CSA and BRS. METHODS: Seventeen male patients in the subacute phase of a first uncomplicated ST-segment elevation AMI and eight healthy male controls without evidence of coronary artery disease underwent polysomnography with simultaneous beat-to-beat ECG- and blood-pressure recordings. Sleep stage specific spontaneous BRS was calculated from blood pressure and RR-interval fluctuations by using the time domain sequential technique. RESULTS: AMI patients revealed to have a higher incidence and longer duration of central apnoeas in all sleep stages, light sleep, deep sleep and dream sleep. There were no significant sleep stage specific differences regarding BRS between groups, however, AMI patients with central sleep apnea exhibited blunted BRS which was inversely correlated to incidences of central apnea in all sleep stages. CONCLUSIONS: Our findings suggest a direct relationship between impaired BRS and repetitive occurrence of CSA by inverse correlation in all sleep stages in the subacute phase of AMI. Thus, reflex cardiac autonomic nervous control, being represented by the BRS, may be the link between CSA and prognosis.

Ventricular repolarization dynamics during different sleep stages in the subacute phase of myocardial infarction.

BACKGROUND: Ventricular arrhythmias after myocardial infarction (MI) are often nocturnal. However, the arrhythmogenic effects of sleep after MI are unknown. We examined the effects of sleep stages on QT dynamicity and tested the hypothesis of a differential effect of sleep stage on the QT/RR relationship after recent MI, versus in healthy controls (HC). METHODS: Polysomnography and electrocardiograms were simultaneously recorded in 21 men in the subacute phase of a first uncomplicated MI, and in 10 age-matched, male HC. QT dynamicity (QT/RR slope) and parameters of QT interval were measured during wakefulness, stages 1-4 of nonrapid eye movement (non-REM) sleep, and REM sleep. RESULTS: Mean QT and RR intervals increased through all sleep stages in both MI survivors and HC. The Bazett-corrected QT interval remained stable from wakefulness throughout all sleep stages. QT/RR slopes remained stable from wakefulness to stage 3 in both groups. However, unlike in MI survivors, the QT/RR slopes decreased and remained significantly lower during deep sleep and REM sleep in HC. CONCLUSION: An abnormal QT/RR relationship in deep sleep and REM sleep was observed after a recent MI, reflecting an insufficient shortening of ventricular repolarization with increasing heart rates, which might have important implications in the nocturnal distribution of ventricular arrhythmias after MI.

Chlamydia pneumoniae multiply in neutrophil granulocytes and delay their spontaneous apoptosis.

The obligate intracellular bacterial pathogen Chlamydia pneumoniae (Cp) is responsible for a range of human diseases, including acute respiratory infection. Although experimental intratracheal infection with Cp results in a massive recruitment of neutrophil granulocytes (polymorphonuclear neutrophils (PMN)), the role of these cells in the defense against Cp is unclear. In this study the interactions of PMN with Cp were investigated. In vitro coincubation experiments showed that human granulocytes were able to internalize Chlamydia in an opsonin-independent manner. Importantly, phagocytosed Cp were not killed; the ingested bacteria survived and multiplied within PMN. Although uninfected granulocytes became apoptotic within 10 h, infected PMN survived up to 90 h. Coincubation with Cp significantly decreased the ratio of apoptotic PMN, as detected by morphological analysis, annexin V, and TUNEL staining. The observed antiapoptotic effect was associated with a markedly lower level of procaspase-3 processing and, consequently, reduced caspase-3 activity in infected PMN. LPS was found as a major, but not exclusive, component responsible for the observed antiapoptotic effect. Chlamydia LPS affected PMN apoptosis both by acting directly on the cells and by inducing the autocrine production of the antiapoptotic cytokine IL-8. These data show that, in contrast to other microbial pathogens that drive phagocytes into apoptosis to escape killing, Cp can extend the life span of neutrophil granulocytes, making them suitable host cells for survival and multiplication within the first hours/days after infection.

Pneumococcal septic shock is associated with the interleukin-10-1082 gene promoter polymorphism.

Polymorphisms in the tumor necrosis factor and interleukin-10 genes, linked to cytokine inducibility, may influence the inflammatory response to infection. We studied the biallelic interleukin-10-1082 promoter, the tumor necrosis factor-alpha-308 promoter, and the lymphotoxin-alpha polymorphisms with regard to the development of septic shock in pneumococcal infection. Sixty-nine patients with pneumococcal disease (61 patients with community-acquired pneumonia, 5 patients with meningitis, and 3 patients with pneumonia and meningitis) and 50 age-matched control subjects were included. The polymorphisms were determined by the polymerase chain reaction. In patients with pneumococcal disease, the lipopolysaccharide-stimulated tumor necrosis factor and interleukin-10 release from whole blood were measured by ELISA. Sepsis severity was documented according to standard criteria. No significant genotypic differences were seen between patients and control subjects. Thirteen of 69 patients with pneumococcal disease developed septic shock. Interleukin-10 allele G homozygous patients had the highest risk for septic shock (odds ratio of 6.1; 95% confidence interval, 1.4-27.2; corrected p = 0.024). The stimulated interleukin-10 release was highest in interleukin-10 G homozygous patients (p = 0.04). In conclusion, interleukin-10 polymorphism, associated with high interleukin-10 inducibility, might influence the outcome of pneumococcal infection via induced immunosuppression and impaired bacterial clearance.