Association of breastfeeding with asthma in young Aboriginal children in Canada

BACKGROUND:

Few studies have investigated the factors associated with asthma in young Aboriginal children.

OBJECTIVE:

To characterize the association of demographic, environmental and early life factors with asthma in young Aboriginal children in Canada.

METHODS:

The 2006 Aboriginal Children’s Survey was conducted among off-reserve Aboriginal children zero to six years of age to obtain information on Aboriginal children’s development and well-being. The prevalence of asthma in Aboriginal children was obtained from the parental report of asthma as diagnosed by a health care professional.

RESULTS:

The prevalence of reported asthma among off-reserve Aboriginal children zero to six years of age (n=14,170) was 9.4%. Asthma prevalence in both exclusively breastfed children (6.8%) and ever but not exclusively breastfed children (9.0%) was significantly lower than that in nonbreastfed children (11.0%). In the multiple logistic regression analysis, exclusive breastfeeding was protective of asthma compared with nonbreastfeeding (OR 0.59 [95% CI 0.44 to 0.78]). Older age groups, male sex, having two or more older siblings, low birth weight, day care attendance and ear infection were significant risk factors for asthma.

CONCLUSIONS:

The prevalence of asthma among young Aboriginal children zero to six years of age living off reserve was slightly lower than that reported for all other Canadian children. Breastfeeding, especially exclusively breastfeeding, was protective of asthma in Aboriginal children, which is consistent with what has been observed in non-Aboriginal children in Canada. Public health interventions intended for reducing asthma incidence in young Aboriginal children should include breastfeeding promotion programs.     

Prevalence of asthma and risk factors for asthma-like symptoms in Aboriginal and non-Aboriginal children in the northern territories of Canada

BACKGROUND:

Few studies have investigated the prevalence and risk factors of asthma in Canadian Aboriginal children.

OBJECTIVE:

To determine the prevalence of asthma and asthma-like symptoms, as well as the risk factors for asthma-like symptoms, in Aboriginal and non-Aboriginal children living in the northern territories of Canada.

METHODS:

Data on 2404 children, aged between 0 and 11 years, who participated in the North component of the National Longitudinal Survey of Children and Youth were used in the present study. A child was considered to have an asthma-like symptom if there was a report of ever having had asthma, asthma attacks or wheeze in the past 12 months.

RESULTS:

After excluding 59 children with missing information about race, 1399 children (59.7%) were of Aboriginal ancestry. The prevalence of asthma was significantly lower (P<0.05) in Aboriginal children (5.7%) than non-Aboriginal children (10.0%), while the prevalence of wheeze was similar between Aboriginal (15.0%) and non-Aboriginal (14.5%) children. In Aboriginal children, infants and toddlers had a significantly greater prevalence of asthma-like symptoms (30.0%) than preschool-aged children (21.5%) and school-aged children (11.5%). Childhood allergy and a mother’s daily smoking habit were significant risk factors for asthma-like symptoms in both Aboriginal and non-Aboriginal children. In addition, infants and toddlers were at increased risk of asthma-like symptoms in Aboriginal children. In analyses restricted to specific outcomes, a mother’s daily smoking habit was a significant risk factor for current wheeze in Aboriginal children and for ever having had asthma in non-Aboriginal children.

CONCLUSIONS:

Asthma prevalence appears to be lower in Aboriginal children than in non-Aboriginal children. The association between daily maternal smoking and asthma-like symptoms, which has been mainly reported for children living in urban areas, was observed in Aboriginal and non-Aboriginal children living in northern and remote communities in Canada.     

The determinants of chronic bronchitis in Aboriginal children and youth

BACKGROUND:

There is limited knowledge concerning chronic bronchitis (CB) in Canadian Aboriginal peoples.

OBJECTIVE:

To determine the prevalence (crude and adjusted) of CB and its associated risk factors in Canadian Aboriginal children and youth six to 14 years of age.

METHODS:

Data from the cross-sectional Aboriginal Peoples Survey were analyzed in the present study. Logistic regression analysis was used to determine risk factors influencing the prevalence of CB among Aboriginal children and youth. The balanced repeated replication method was used to compute standard errors of regression coefficients to account for clustering inherent in the study design. The outcome of interest was based on the question: “Have you been told by a doctor, nurse or other health professional that you have chronic bronchitis?” Demographics, environment and population characteristics (predisposing and enabling resources) were tested for an association with CB.

RESULTS:

The prevalence of CB was 3.1% for boys and 2.8% for girls. Other significant risk factors of CB were age (OR 1.38 [95% CI 1.24 to 1.52] for 12 to 14 year olds versus six to eight year olds), income (OR 2.28 [95% CI 2.02 to 2.59] for income category <$25,000/year versus ≥$85,000/year), allergies (OR 1.96 [95% CI 1.78 to 2.16] for having allergies versus no allergies), asthma (OR 7.61 [ 95% CI 6.91 to 8.37] for having asthma versus no asthma) and location of residence (rural/urban and geographical location). A significant two-way interaction between sex and body mass index indicated that the relationship between the prevalence of CB and body mass index was modified by sex.

DISCUSSION:

The prevalence of CB was related to well-known risk factors among adults, including older age and lower annual income.     

Factors associated with the appropriate use of asthma drugs

BACKGROUND:

When used properly, asthma drugs can reduce asthma-related morbidity and mortality.

OBJECTIVE:

To assess the use of asthma drugs, and to identify factors associated with appropriateness of use among patients 12 to 45 years of age.

METHODS:

Asthmatic patients were interviewed about their asthma drug(s) use and the factors potentially associated with appropriateness of use according to the 2003 Canadian Asthma Consensus Conference guidelines. To determine the factors associated with the appropriate use of asthma drugs, a multivariate logistic regression model was built using a stepwise procedure, and ORs and associated 95% CIs were calculated.

RESULTS:

Of the 349 study participants, 43 (12.3%) reported appropriate use of their asthma drugs. Respondents who were more likely to report appropriate use were patients with sound knowledge of their asthma drugs (OR 2.61 [95% CI 1.29 to 5.29]), those in good, very good or excellent self-perceived health (OR 3.37 [95% CI 1.31 to 8.71]), those who had consulted a specialist during the preceding year (OR 2.28 [95% CI 1.05 to 4.97]) and those who declared themselves short of drugs due to a lack of money (OR 2.78 [95% CI 1.26 to 6.17]).

CONCLUSIONS:

Results of the present study suggested that recommendations in the current guidelines regarding the appropriate use of asthma medications are being poorly implemented. Educational interventions with the aim of improving quality of care and knowledge about asthma drugs should be offered.     

The prevalence and predictors of tuberculin positivity in subjects screened for reasons other than contact investigation

BACKGROUND:

No previous studies have estimated the rates of tuberculin positivity (TP) in noncontact populations within the same community, which is important for prioritizing and implementing preventive measures.

OBJECTIVES:

To estimate the prevalence and predictors of TP in noncontact populations.

METHODS:

A retrospective analysis of tuberculin results of non-contact populations screened in British Columbia from 1990 to 2002 was conducted.

RESULTS:

The period prevalence of TP in 59,791 screened subjects was 12.7% (95% CI 12.4% to 13.0%), 30.4% (95% CI 28.2% to 32.7%) and 60.9% (95% CI 60.3% to 61.6%) for Canadian-born non-Aboriginals (CBNAs), Canadian-born Aboriginals (CBAs) and foreign born (FB), respectively. After controlling for age and sex, independent predictors of TP included Bacille Calmette-Guérin (BCG) vaccination (OR 19.6, 95% CI 17.9 to 21.5), country of birth (CBA: OR 2.87, 95% CI 2.44 to 3.37; FB: OR 3.67, 95% CI 3.34 to 4.03) and the following populations: correctional centre residents (OR 4.14, 95% CI 1.87 to 9.15), residents of long-term care and community care facilities (OR 1.79, 95% CI 1.44 to 2.23), immigrants (OR 1.75, 95 % CI 1.50 to 2.04), health centre employees (OR 1.71, 95 % CI 1.56 to 1.88), volunteers (OR 1.38, 95% CI 1.14 to 1.68), self-referred healthy subjects (OR 1.30, 95% CI 1.15 to 1.48) and students (OR 1.27, 95% CI 1.19 to 1.35). CBAs, FB and male subjects were less likely to react to tuberculin than CBNAs and female subjects among those vaccinated with Bacille Calmette-Guérin (P<0.05).

CONCLUSIONS:

Rates of TP correlate with disease rates by sex and origin. The continuation of tuberculin screening programs is warranted in noncontact populations with high TP rates, where unknown exposure to active cases is more likely to occur. Further research is needed to determine the reasons why a higher response to tuberculin occurs in BCG-vaccinated women and CBNAs.     

Use of complementary and alternative medicine in children with asthma

BACKGROUND:

Because of the potential risk of interaction with, and underuse of, conventional medications, it is important to document the prevalence of the use of complementary and alternative medicines (CAMs) in asthmatic children.

OBJECTIVE:

To ascertain the prevalence and type of CAMs, and to identify factors associated with their use.

METHODS:

A cross-sectional survey of children who presented to the Asthma Centre of The Montreal Children’s Hospital (Montreal, Quebec) between 1999 and 2007 was conducted. At the initial consultation, parents completed a questionnaire inquiring, in part, about CAM use. Computerized health records provided information regarding patient characteristics and their condition.

RESULTS:

The median age of the 2027 children surveyed was 6.1 years (interquartile range 3.3 to 10.5 years); 58% were male and 59% of children had persistent asthma. The prevalence of CAM use was 13% (95% CI 12% to 15%). Supplemental vitamins (24%), homeopathy (18%) and acupuncture (11%) were the most commonly reported CAMs. Multivariable logistic regression analysis confirmed the association of CAM use with age younger than six years (OR 1.86; 95% CI 1.20 to 2.96), Asian ethnicity (OR 1.89; 95% CI 1.01 to 3.52), episodic asthma (OR 1.88; 95% CI 1.08 to 3.28) and poor asthma control (OR 1.98; 95% CI 1.80 to 3.31).

CONCLUSION:

The prevalence of reported CAM use among Quebec children with asthma remained modest (13%), with vitamins, homeopathy and acupuncture being the most popular modalities. CAM use was associated with preschool age, Asian ethnicity, episodic asthma and poor asthma control.     

Treatment of chronic hepatitis C in a Canadian Aboriginal population: Results from the PRAIRIE study

BACKGROUND:

The Aboriginal population of Canada is at increased risk of exposure to the hepatitis C virus (HCV). Previous data indicate that spontaneous clearance of HCV occurs more often in Aboriginals than Caucasians. Whether this enhanced response extends to antiviral therapy for chronic HCV remains to be determined.

OBJECTIVES:

To document and compare the biochemical and virological responses to antiviral therapy in HCV-infected Canadian Aboriginals and Caucasians.

METHODS:

A total of 101 treatment-naive adult patients (46 Aboriginal, 55 Caucasian) with chronic HCV genotype 1 infections were prospectively treated with pegylated-interferon and ribavirin and followed as per national guidelines.

RESULTS:

Aboriginals had higher HCV-RNA loads at baseline (6.42log₁₀ versus 5.98log₁₀; P<0.03). Although normalization of serum aminotransferase levels, decreases in viral loads, and rapid, early and end-of-treatment virological responses were similar in the two cohorts, sustained virological responses were significantly lower in Aboriginals (35% versus 55%; P=0.047). Premature discontinuation of treatment and/or loss of patients to follow-up was common (Aboriginals 37%, Caucasians 27%). Treatment-related side effects were similar in the two cohorts.

CONCLUSION:

Despite higher rates of spontaneous HCV clearance, the response to antiviral therapy was similar, if not lower, in Aboriginals compared with Caucasians with chronic HCV genotype 1 infections. Compliance with treatment is an issue that needs to be addressed in the management of these patients.     

Endoscopic band ligation versus pharmacological therapy for variceal bleeding in cirrhosis: a meta-analysis

OBJECTIVE:

To conduct a meta-analysis of published, full-length, randomized controlled trials evaluating the efficacy of endoscopic band ligation (EBL) versus pharmacological therapy for the primary and secondary prophylaxis of variceal hemorrhage in patients with cirrhosis.

METHODS:

Literature searches were conducted using the PubMed, EMBASE and Cochrane Library databases. Eighteen randomized clinical trials that fulfilled the inclusion criteria were further pooled into a meta-analysis.

RESULTS:

Among 1023 patients in 12 trials comparing EBL with beta-blockers for primary prevention, there was no significant difference in gastrointestinal bleeding (RR 0.79 [95% CI 0.61 to 1.02]), all-cause deaths (RR 1.06 [95% CI 0.86 to 1.30]) or bleeding-related deaths (RR 0.66 [95% CI 0.38 to 1.16]). There was a reduced trend toward significance in variceal bleeding with EBL compared with beta-blockers (RR 0.72 [95% CI 0.54 to 0.96]). However, variceal bleeding was not significantly different between the two groups in high-quality trials (RR 0.84 [95% CI 0.60 to 1.17]). Among 687 patients from six trials comparing EBL with beta-blockers plus isosorbide mononitrate for secondary prevention, there was no effect on either gastrointestinal bleeding (RR 0.95 [95% CI 0.65 to 1.40]) or variceal bleeding (RR 0.89 [95% CI 0.53 to 1.49]). The risk for all-cause deaths in the EBL group was significantly higher than in the medical group (RR 1.25 [95% CI 1.01 to 1.55]); however, the rate of bleeding-related deaths was unaffected (RR 1.16 [95% CI 0.68 to 1.97]).

CONCLUSIONS:

Both EBL and beta-blockers may be considered first-line treatments to prevent first variceal bleeding, whereas beta-blockers plus isosorbide mononitrate may be the best choice for the prevention of rebleeding.     

Active and uncontrolled asthma among children exposed to air stack emissions of sulphur dioxide from petroleum refineries in Montreal,Quebec: A cross-sectional study

BACKGROUND:

Little attention has been devoted to the effects on children’s respiratory health of exposure to sulphur dioxide (SO₂) in ambient air from local industrial emissions. Most studies on the effects of SO₂ have assessed its impact as part of the regional ambient air pollutant mix.

OBJECTIVE:

To examine the association between exposure to stack emissions of SO₂ from petroleum refineries located in Montreal’s (Quebec) east-end industrial complex and the prevalence of active asthma and poor asthma control among children living nearby.

METHODS:

The present cross-sectional study used data from a respiratory health survey of Montreal children six months to 12 years of age conducted in 2006. Of 7964 eligible households that completed the survey, 842 children between six months and 12 years of age lived in an area impacted by refinery emissions. Ambient SO₂ exposure levels were estimated using dispersion modelling. Log-binomial regression models were used to estimate crude and adjusted prevalence ratios (PRs) and 95% CIs for the association between yearly school and residential SO₂ exposure estimates and asthma outcomes. Adjustments were made for child’s age, sex, parental history of atopy and tobacco smoke exposure at home.

RESULTS:

The adjusted PR for the association between active asthma and SO₂ levels was 1.14 (95% CI 0.94 to 1.39) per interquartile range increase in modelled annual SO₂. The effect on poor asthma control was greater (PR=1.39 per interquartile range increase in modelled SO₂ [95% CI 1.00 to 1.94]).

CONCLUSIONS:

Results of the present study suggest a relationship between exposure to refinery stack emissions of SO₂ and the prevalence of active and poor asthma control in children who live and attend school in proximity to refineries.     

Incidence of pulmonary embolism during COPD exacerbation,

OBJECTIVE:

Because pulmonary embolism (PE) and COPD exacerbation have similar presentations and symptoms, PE can be overlooked in COPD patients. Our objective was to determine the prevalence of PE during COPD exacerbation and to describe the clinical aspects in COPD patients diagnosed with PE.

METHODS:

This was a prospective study conducted at a university hospital in the city of Ankara, Turkey. We included all COPD patients who were hospitalized due to acute exacerbation of COPD between May of 2011 and May of 2013. All patients underwent clinical risk assessment, arterial blood gas analysis, chest CT angiography, and Doppler ultrasonography of the lower extremities. In addition, we measured D-dimer levels and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) levels.

RESULTS:

We included 172 patients with COPD. The prevalence of PE was 29.1%. The patients with pleuritic chest pain, lower limb asymmetry, and high NT-pro-BNP levels were more likely to develop PE, as were those who were obese or immobile. Obesity and lower limb asymmetry were independent predictors of PE during COPD exacerbation (OR = 4.97; 95% CI, 1.775-13.931 and OR = 2.329; 95% CI, 1.127-7.105, respectively).

CONCLUSIONS:

The prevalence of PE in patients with COPD exacerbation was higher than expected. The association between PE and COPD exacerbation should be considered, especially in patients who are immobile or obese.     

Exacerbations of COPD and symptoms of gastroesophageal reflux: a systematic review and meta-analysis

OBJECTIVE:

To examine the relationship between gastroesophageal reflux (GER) and COPD exacerbations.

METHODS:

We conducted a systematic search of various electronic databases for articles published up through December of 2012. Studies considered eligible for inclusion were those dealing with COPD, COPD exacerbations, and GER; comparing at least two groups (COPD vs. controls or GER vs. controls); and describing relative risks (RRs) and prevalence ratios-or ORs and their respective 95% CIs (or presenting enough data to allow further calculations) for the association between GER and COPD-as well as exacerbation rates. Using a standardized form, we extracted data related to the study design; criteria for GER diagnosis; age, gender, and number of participants; randomization method; severity scores; methods of evaluating GER symptoms; criteria for defining exacerbations; exacerbation rates (hospitalizations, ER visits, unscheduled clinic visits, prednisone use, and antibiotic use); GER symptoms in COPD group vs. controls; mean number of COPD exacerbations (with symptoms vs. without symptoms); annual frequency of exacerbations; GER treatment; and severity of airflow obstruction.

RESULTS:

Overall, GER was clearly identified as a risk factor for COPD exacerbations (RR = 7.57; 95% CI: 3.84-14.94), with an increased mean number of exacerbations per year (mean difference: 0.79; 95% CI: 0.22-1.36). The prevalence of GER was significantly higher in patients with COPD than in those without (RR = 13.06; 95% CI: 3.64-46.87; p < 0.001).

CONCLUSIONS:

GER is a risk factor for COPD exacerbations. The role of GER in COPD management should be studied in greater detail.     

Seroprevalences of hepatitis B virus and hepatitis C virus among participants of an Asian health fair in the Lower Mainland,British Columbia

BACKGROUND:

The seroprevalences of hepatitis B virus (HBV) and hepatitis C virus (HCV) are 0.4% and 0.8%, respectively, in Canada, but varying rates have been reported in different populations.

OBJECTIVES:

To determine the seroprevalences of HBV and HCV among attendees of an Asian health fair in the Lower Mainland, British Columbia, as well as to correlate questionnaire answers regarding vaccination status to serological profiles.

METHODS:

Attendees at an Asian health fair were invited to participate in the present study on a voluntary basis. They provided answers to a questionnaire including ethnicity and vaccination status. Blood was then drawn for HBV and HCV serology. Active HBV was defined as HBV surface antigen (HBsAg) positive while HCV seroprevalence was defined as HCV antibody reactive. Previous exposure to HBV was defined as HBV core antibody (anti-HBc) positive and HBsAg negative. Nonimmunity was defined as anti-HBc negative and HBV surface antibody negative. Only those with correct demographic information matched to serological results were included in the study.

RESULTS:

There were 192 consenting attendees of the fair, of whom 112 were included in the study. Of the participants, 91% were Chinese. Active HBV infection was found in three participants (2.7% [95% CI 0.6% to 7.6%]) and HCV infection was found in two participants (1.8% [95% CI 0.2% to 6.3%]). More than 40% of participants had been previously exposed to HBV (42% [95% CI 33% to 51%]). Almost 20% demonstrated nonimmunity to HBV (19% [95% CI 12% to 27%]). There was significant discordance when questionnaire answers regarding vaccination status were compared with serological profiles.

CONCLUSION:

The seroprevalences of HBV and HCV in this cohort were 2.7% and 1.8%, respectively – higher than nationally reported rates. Our results highlight that the lack of knowledge of HBV infection and vaccination status remains a significant clinical issue in the Asian community of British Columbia.     

Opposing trends in the prevalence of health professional-diagnosed asthma by sex: A Canadian National Population Health Survey study

BACKGROUND:

The prevalence of asthma is on the rise worldwide, with large variations in prevalence existing between and within countries. Little is known regarding the variation in asthma prevalence in adults living in rural and urban settings.

OBJECTIVES:

Using questionnaire data from the Canadian National Population Health Survey, the prevalence of asthma at four time periods (1994/1995 [cycle 1], 1996/1997 [cycle 2], 1998/1999 [cycle 3] and 2000/2001 [cycle 4]) was compared between rural and urban populations stratified by sex, smoking status and age group. Asthma was defined as a positive response to the question: “Do you have asthma diagnosed by a health professional?”

METHODS:

To account for the complexity of the survey design, the bootstrap method was used to calculate prevalences and 95% CIs.

RESULTS:

Overall, the prevalence of asthma increased from 7.3% (cycle 1) to 7.5% (cycle 4). After stratifying by sex, the asthma prevalence decreased among men, but in women, there was a steady increase. Asthma prevalence increased for both the rural population and the urban population. After stratifying each cycle by sex and location (rural or urban), both rural and urban men showed a decrease in asthma prevalence. On dividing according to age groups (0 to 14 years, 15 to 34 years, 35 to 64 years, and 65 years and older), the prevalence of asthma was greatest in the 15- to 34-year age group of urban and rural women.

CONCLUSIONS:

Asthma prevalence increased among rural and urban women. The prevalence of asthma was highest among female smokers and male nonsmokers when stratified by smoking status. Based on these findings, the rate of increase in asthma prevalence is different for men and women.     

Oral corticosteroid use and the risk of acute myocardial infarction in chronic obstructive pulmonary disease

BACKGROUND

Given the limited efficacy of oral corticosteroids in treating chronic obstructive pulmonary disease (COPD), the possible cardiac side effects of oral corticosteroids are of particular concern in an elderly population. The impact of the use of oral corticosteroids on the risk of acute myocardial infarction (AMI) in a cohort of patients with COPD was studied.

METHODS

The Saskatchewan health services databases were used to form a population-based cohort of 5648 patients aged 55 years or older who received a first treatment for COPD between 1990 and 1997. A nested case-control analysis was conducted: 371 cases presenting with a first myocardial infarction were matched with 1864 controls according to the length of follow-up, the date of cohort entry and age. Conditional logistic regression was used to adjust for sex, severity of COPD, systemic hypertension, diabetes and prior cardiovascular disease.

RESULTS

Only the current use of corticosteroids was associated with an increased risk of AMI (adjusted RR=2.01 [95% CI 1.13 to 3.58]), particularly when the current dose was larger than 25 mg/day of prednisone or the equivalent (adjusted RR=3.22 [95% CI 1.42 to 7.34]). This observed increase in risk rapidly returned to baseline after the cessation of the medication, suggesting that the use of such high doses reflected the treatment of acute exacerbations of the disease.

CONCLUSIONS

An association was found between the current use of oral corticosteroids and the occurrence of an AMI, suggesting that acute exacerbations of COPD are associated with an increased risk of acute coronary syndromes.     

HIV disease progression to CD4 count <200 cells/μL and death in Saskatoon,Saskatchewan

OBJECTIVE:

To characterize and identify determinants of HIV disease progression among a predominantly injection drug use (IDU) HIV population in the highly active antiretroviral therapy era.

METHODS:

The present retrospective study was based on 343 HIV patients diagnosed from 2005 to 2010 from two clinics in Saskatoon, Saskatchewan. Disease progression was defined as the time from diagnosis to immunological AIDS (CD4 count <200 cells/μL) and death. Uni- and multivariable Cox proportional hazards models were used.

RESULTS:

Of the 343 patients, 79% had a history of IDU, 77% were hepatitis C virus (HCV) coinfected and 67% were of Aboriginal descent. The one-year and three-year immunological AIDS-free probabilities were 78% and 53%, respectively. The one-year and three-year survival probabilities were 97% and 88%, respectively. Multicollinearity among IDU, HCV and ethnicity was observed and, thus, separate models were built. HCV coinfection (HR 2.9 [95% CI 1.2 to 6.9]) was a significant predictor of progression to immunological AIDS when controlling for baseline CD4 counts, treatment, age at diagnosis and year of diagnosis. For survival, only treatment use was a significant predictor (HR 0.34 [95% CI 0.1 to 0.8]). HCV coinfection was marginally significant (P=0.067).

CONCLUSION:

Baseline CD4 count, HCV coinfection, year of diagnosis and treatment use were significant predictors of disease progression. This highlights the importance of early treatment and the need for targeted interventions for these particularly vulnerable populations to slow disease progression.     

Association between proximity to major roads and sputum cell counts

BACKGROUND:

Air pollution caused by motor vehicle emissions has been associated with exacerbations of obstructive airway diseases; however, the nature of the resulting bronchitis has not been quantified.

OBJECTIVE:

To examine whether proximity to major roads or highways is associated with an increase in sputum neutrophils or eosinophils, and to evaluate the effect of proximity to roads on spirometry and exacerbations in patients with asthma.

METHODS:

A retrospective study of 485 sputum cell counts from patients attending a tertiary chest clinic in Hamilton, Ontario, identified eosinophilic or neutrophilic bronchitis. Patients’ residences were geocoded to the street network of Hamilton using geographic information system software. Associations among bronchitis, lung function, and proximity to major roads and highways were examined using multinomial logistic and multivariate linear regression analyses adjusted for patient age, smoking status and corticosteroid medications.

RESULTS:

Patients living within 1000 m of highways showed an increased risk of bronchitis (OR 3.8 [95% CI 1.0 to 13.7]; P<0.05), particularly neutrophilic bronchitis (OR 4.7 [95% CI 1.2 to 18.7]; P<0.05) as well as an increased risk of an asthma diagnosis (OR 1.9 [95% CI 1.0 to 3.4]; P<0.05). Patients living within 300 m of a major road were at increased risk for an asthma exacerbation (OR 1.9 [95% CI 1.5 to 15.5]; P<0.01) and lower lung function, particularly in women (P=0.036).

CONCLUSION:

In patients with airway diseases, living close to a highway or major road was associated with neutrophilic bronchitis, an increased risk of asthma diagnosis, asthma exacerbations and lower lung function.     

Prevalence and predictors of sleep disturbance among liver diseases in long-term transplant survivors

BACKGROUND:

Patients with cirrhosis are known to experience sleep disturbance, which negatively impacts health-related quality of life.

OBJECTIVE:

To assess the prevalence and predictors of sleep disturbance before and after liver transplantation (LT).

METHODS:

Both pre- and post-LT patients were administered the Basic Nordic Sleep Questionnaire. The primary outcome was overall sleep satisfaction; the secondary outcomes were sleep latency and sleep duration.

RESULTS:

Eighty-three patients participated pre-LT and 273 post-LT. Overall, participants having completed both pre- and post-LT questionnaires reported satisfactory sleep 61% of the time before LT and 65% of the time after LT. However, on review of all questionnaires, patients with alcoholic liver disease (ETOH) experienced dramatically less sleep disturbance (OR 0.13 [95% CI 0.03 to 0.60]) post-LT, whereas those with hepatitis C remained without improvement (OR 0.90 [95% CI [0.38 to 2.15]). On logistic regression, patients with ETOH had statistically less sleep satisfaction pre-LT (OR 5.8 [95% CI 1.0 to 40.5]) and significantly better sleep satisfaction post-LT (OR 0.50 [95% CI 0.20 to 1.00]) compared with those with hepatitis C. In addition, both ETOH and other conditions had significantly better sleep latency than hepatitis C patients.

CONCLUSIONS:

Sleep parameters for patients who undergo LT for hepatitis C do not improve following LT as much as they do in patients transplanted for ETOH. Following LT, patients transplanted for ETOH are significantly more satisfied with their sleep than those transplanted for hepatitis C. Physicians should address and manage sleep quality after LT, so as to ultimately improve quality of life.     

Asthma is not enough: Continuation of smoking among parents with an asthmatic child

BACKGROUND:

Ideally, on diagnosis of asthma in a child, parents are counselled to decrease environmental tobacco smoke exposure to their children.

OBJECTIVE:

To determine whether a diagnosis of asthma in children altered parental smoking behaviour toward a reduction in environmental tobacco smoke exposure.

METHODS:

In 2002/2003, a survey was sent to 12,556 households with children born in 1995 in Manitoba. Parents were asked whether their seven-year-old child had asthma, and whether smokers were present in the home in 1995 and/or currently. The likelihood (OR) of a change in parental smoking behaviour was determined according to the presence of asthma in their child, a family history of asthma, the location of residence (rural or urban) and their socioeconomic status.

RESULTS:

A total of 3580 surveys (28.5%) were returned. The overall prevalence of parental smoking in 1995 and 2002/2003 was 32.2% and 23.4%, respectively (31.9%/23.2% and 32.3%/23.6% in rural and urban environments, respectively). In 2002/2003, the prevalence of parental smoking in homes with asthmatic children was 29.8%. Parents were not more likely to quit smoking (OR=1.01, 95% CI 0.66 to 1.54) or smoke outside (OR=1.02, 95% CI 0.56 to 1.83) if their child developed asthma. Parental smoking behaviour (quit smoking or smoked outside) did not change if there was a positive family history of asthma (OR=1.04, 95% CI 0.78 to 1.37), if they lived in a rural or urban location (OR=0.94, 95% CI 0.71 to 1.23), or if they were from a low- or high-income household (OR=1.12, 95% CI 0.85 to 1.47).

CONCLUSIONS:

The likelihood of altering parental smoking behaviour occurred independently of a diagnosis of asthma in their child, a family history of asthma, the location of residence and their socioeconomic status.     

Predictors of a variceal source among patients presenting with upper gastrointestinal bleeding

BACKGROUND:

Patients with upper gastrointestinal bleeding (UGIB) require an early, tailored approach best guided by knowledge of the bleeding lesion, especially a variceal versus a nonvariceal source.

OBJECTIVE:

To identify, by investigating a large national registry, variables that would be predictive of a variceal origin of UGIB using clinical parameters before endoscopic evaluation.

METHODS:

A retrospective study was conducted in 21 Canadian hospitals during the period from January 2004 until the end of May 2005. Consecutive charts for hospitalized patients with a primary or secondary discharge diagnosis of UGIB were reviewed. Data regarding demographics, including historical, physical examination, initial laboratory investigations, endoscopic and pharmacological therapies administered, as well as clinical outcomes, were collected. Multivariable logistic regression modelling was performed to identify clinical predictors of a variceal source of bleeding.

RESULTS:

The patient population included 2020 patients (mean [± SD] age 66.3±16.4 years; 38.4% female). Overall, 215 (10.6%) were found to be bleeding from upper gastrointestinal varices. Among 26 patient characteristics, variables predicting a variceal source of bleeding included history of liver disease (OR 6.36 [95% CI 3.59 to 11.3]), excessive alcohol use (OR 2.28 [95% CI 1.37 to 3.77]), hematemesis (OR 2.65 [95% CI 1.61 to 4.36]), hematochezia (OR 3.02 [95% CI 1.46 to 6.22]) and stigmata of chronic liver disease (OR 2.49 [95% CI 1.46 to 4.25]). Patients treated with antithrombotic therapy were more likely to experience other causes of hemorrhage (OR 0.44 [95% CI 0.35 to 0.78]).

CONCLUSION:

Presenting historical and physical examination data, and initial laboratory tests carry significant predictive ability in discriminating variceal versus nonvariceal sources of bleeding.     

A meta-analysis of nutritional supplementation for management of hospitalized alcoholic hepatitis

BACKGROUND:

Alcoholic liver disease (ALD) is associated with a high risk of morbidity and mortality. Malnutrition accompanies this condition and may be both a consequence of and contributor to the pathology. Many trials have investigated the benefits of providing supplemental nutrition in the management of patients with ALD. The present study is a meta-analysis of the available evidence.

METHOD:

A meta-analysis of randomized controlled studies comparing nutritional supplementation plus a normal hospital diet versus diet alone.

RESULTS:

Seven randomized controlled studies including 262 patients with ALD were identified. Pooled analysis revealed no statistical difference in mortality between groups given special nutritional therapy versus a normal balanced diet (OR 0.80 [95% CI 0.42 to 1.52]). In addition, nutrition did not significantly improve ascites (OR 1.29 [95% CI 0.52 to 3.20]) or any biochemical parameters. However, encephalopathy showed a significant improvement or resolution (OR 0.24 [95% CI 0.06 to 0.93]).

CONCLUSION:

Nutritional supplementation provided no mortality benefit in patients with ALD, and neither ascites nor biochemical parameters significantly improved. However, encephalopathy was significantly ameliorated and, therefore, nutritional supplementation should be encouraged in that setting.