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1.  Excessive daytime sleepiness among rural residents in Saskatchewan 
Obstructive sleep apnea and its sequelae are emerging public health issues in North America, and symptoms are often under-recognized or under-reported. Although several patient factors have been identified, limited data regarding the prevalence of and predictors for excessive daytime sleepiness in rural or remote populations area available. Accordingly, this study used Epworth Sleepiness Scale scores to evaluate daytime sleepiness in a large rural population participating in the Saskatchewan Rural Health Study.
BACKGROUND:
Obstructive sleep apnea (OSA) is a common diagnosis in clinical practice. Excessive daytime sleepiness may be a warning for possible OSA.
OBJECTIVES:
To assess the prevalence of excessive daytime sleepiness as measured by the Epworth Sleepiness Scale (ESS) in a rural community population; potential risk factors for OSA were also assessed.
METHODS:
In 2010, a baseline respiratory health questionnaire within the Saskatchewan Rural Health Study was mailed to 11,982 households in Saskatchewan. A total of 7597 adults within the 4624 (42%) respondent households completed the ESS questionnaire. Participants were categorized according to normal or high (>10) ESS scores. Data obtained included respiratory symptoms, doctor-diagnosed sleep apnea, snoring, hypertension, smoking and demographics. Body mass index was calculated. Multivariable logistic regression analysis examined associations between high ESS scores and possible risk factors. Generalized estimating equations accounted for the two-tiered sampling procedure of the study design.
RESULTS:
The mean age of respondents was 55.0 years and 49.2% were male. The prevalence of ESS>10 and ‘doctor diagnosed’ OSA were 15.9% and 6.0%, respectively. Approximately 23% of respondents reported loud snoring and 30% had a body mass index >30 kg/m2. Of those with ‘doctor-diagnosed’ OSA, 37.7% reported ESS>10 (P<0.0001) and 47.7% reported loud snoring (P<0.0001). Risk of having an ESS>10 score increased with age, male sex, obesity, lower socioeconomic status, marriage, loud snoring and doctor-diagnosed sinus trouble.
CONCLUSIONS:
High levels of excessive daytime sleepiness in this particular rural population are common and men >55 years of age are at highest risk. Examination of reasons for residual sleepiness and snoring in persons with and without sleep apnea is warranted.
PMCID: PMC4173890  PMID: 24791255
Epworth Sleepiness Scale; Farm; Nonfarm; Obesity; Rural; Sleep apnea; Snoring; Socioeconomic
2.  CD14 Gene Variants and Their Importance for Childhood Croup, Atopy, and Asthma 
Disease Markers  2013;35(6):765-771.
Background. The CD14 gene has an important role in the detection of inflammatory provoking pathogens and in the ensuing signaling of the innate immune response. We assessed the role of CD14 C-159T, G-1359T in the expression of asthma, croup, and allergy in Canadian school children of ages 6 to 14 years. Methods. Children attending schools in a rural community participated in a cross-sectional survey of respiratory health. Following consent, we conducted clinical assessments to collect buccal swabs for genotyping and perform skin prick testing (SPT) to determine atopic status. Genotyping and SPT results were available for 533 and 499 children, respectively. Separate multivariable analyses that included both polymorphisms were conducted for each phenotype. Results. The prevalence of asthma, allergy, and croup was 18.6%, 22.4%, and 6.6%, respectively. Children with the T/T variant of CD14 G-1359T were more likely to have physician diagnosed asthma (26.8%). Children with C/C variant of CD14 C-159T had a significantly lower prevalence of croup (2.6%). Haplotype analyses of the two CD14 polymorphisms showed that individuals with the T|T haplotype combination were significantly more likely to have asthma (P = 0.014). Conclusions. In this study, CD14 variants are important for the expression of croup and asthma but not atopy.
doi:10.1155/2013/434920
PMCID: PMC3856132  PMID: 24347797
3.  Obesity, Diet, and Activity in relation to Asthma and Wheeze among Rural Dwelling Children and Adolescents 
Journal of Obesity  2013;2013:315096.
Aims and Objectives. We investigated associations between weight status, activity level, and diet with asthma or wheeze as well as the interrelationship between these factors. Methods. We conducted a case-control study of 6–18-year olds from 2005 to 2007. Cases (n = 87) were subjects reporting episodes or breathing medication use along with doctor-diagnosed asthma or wheeze in the past 12 months. Controls were randomly selected (n = 208) and without asthma or wheeze. Data regarding health outcomes, diet, and activity were obtained from questionnaire. Objectively measured height and weight were collected. Results. In the adjusted analysis, there was a trend (P = 0.07) towards an increased risk of asthma or wheeze associated with high fast food and/or pop consumption. Among cases, a significantly lower proportion (66%) classified as overweight participated in hard exercise in ≥9 of the past 14 days compared to those who were not overweight (86%). This pattern was not seen among controls (76% participating in hard exercise versus 78%, resp.). However, based on perceived weight status by the parent, the patterns were similar regardless of case-control status. Conclusions. Overweight status may negatively impact activity level among those with asthma or wheeze. Efforts should be made to encourage healthy food choices, and activity programming must consider the needs of overweight children with asthma.
doi:10.1155/2013/315096
PMCID: PMC3804370  PMID: 24191194
4.  Prevalence, risk factors and co-morbidities of diabetes among adults in rural Saskatchewan: the influence of farm residence and agriculture-related exposures 
BMC Public Health  2013;13:7.
Background
Although rural Canadians are reported to have higher rates of diabetes than others, little is known about the relative influence of known versus agriculture-related risk factors. The purpose of this research was to carry out a comprehensive study of prevalence, risk factors and co-morbidities of diabetes among adults in rural Saskatchewan and to determine possible differences between those living on and off farms.
Methods
In 2010, we conducted a baseline mail-out survey (Saskatchewan Rural Health Study) of 11,982 households located in the province′s four agricultural quadrants. In addition to self-reported physician-diagnosed diabetes, the questionnaire collected information from farm and small town cohorts on possible diabetes determinants including lifestyle, family history, early life factors and environmental/agricultural-related exposures. Clustering effect within households was adjusted using Generalized Estimating Equations approach.
Results
Responses were obtained from 4624 (42%) households comprising 8208 males and females aged 18 years or older and 7847 self-described Caucasian participants (7708 with complete information). The overall age-standardized diabetes prevalence for the latter was 6.35% but people whose primary residence was on farms had significantly lower diabetes prevalence than those living in non-farm locations (5.11% versus 7.33% respectively; p<0.0001). Diabetes risk increased with age and affected almost 17% of those older than 65 (OR 2.57; CI′ 1.63, 4.04 compared to those aged 18–45). Other known independent risk factors included family history of diabetes (OR 2.50 [CI′s 1.94, 3.23] if father; OR 3.11 [CI′s 2.44, 3.98] if mother), obesity (OR 2.66; CI′s 1.86, 3.78), as well as lower socioeconomic status, minimal/no alcohol intake and smoking. The most original finding was that exposure to insecticides conferred an increased risk for diabetes among males (OR 1.83; CI′s 1.15, 2.91). Finally, the co-morbidities with the strongest independent association with diabetes were heart disease and hypertension.
Conclusions
While known diabetes risk factors are important determinants of diabetes in the agricultural zones of Saskatchewan, on-farm residence is protective and appears related to increased outdoor activities. In contrast, we have now shown for the first time that exposure to insecticides is an independent risk factor for diabetes among men in rural Canada.
doi:10.1186/1471-2458-13-7
PMCID: PMC3552674  PMID: 23289729
Diabetes; Rural; Agriculture; Insecticides; Farm; Exposures
5.  The association between endotoxin and lung function among children and adolescents living in a rural area 
Increased levels of endotoxin found in rural and agricultural areas are an environmental exposure believed to cause a paradoxical proinflammatory effect on respiratory health that can exacerbate asthma. Previous studies involving adults have demonstrated an association between high endotoxin levels and lower lung function. Apart from occupational settings, however, few studies have investigated the relationship between lung function and endotoxin exposure, such as environmental tobacco smoke, especially in children. This study examined the modifying effects of sex, pre-existing asthma and other environmental exposures, including tobacco smoke, in children living in rural communities in Saskatchewan.
BACKGROUND/OBJECTIVES:
Knowledge of the effects of domestic endotoxin on children’s lung function is limited. The association between domestic endotoxin and asthma or wheeze and lung function among school-age children (six to 18 years of age) was examined. The interaction between endotoxin and other personal and environmental characteristics and lung function was also assessed.
METHODS:
A case-control study was conducted in and around the rural community of Humboldt, Saskatchewan, between 2005 and 2007. Parents of cases reported either doctor-diagnosed asthma or wheeze in the previous year. Controls were randomly selected from those not reporting these conditions. Data were collected by questionnaire to ascertain symptoms and conditions, while spirometry was used to measure lung function including forced vital capacity and forced expiratory volume in 1 s. Dust collected from the child’s play area floor and the child’s mattress was used to quantify endotoxin, and saliva was collected to quantify cotinine levels and assess tobacco smoke exposure.
RESULTS:
There were 102 cases and 207 controls included in the present study. Lower forced expiratory volume in 1 s was associated with higher mattress endotoxin load among female cases (beta=−0.25, SE=0.07 [P<0.01]). There was a trend toward lower forced vital capacity, which was associated with higher play area endotoxin load among cases with high tobacco smoke exposure (beta=−0.17, SE=0.09 [P<0.10]).
CONCLUSIONS:
Findings indicated that high endotoxin levels present in common household areas of rural children with asthma or wheeze may also affect their lung function. These associations may be potentiated by tobacco smoke exposure and female sex.
PMCID: PMC3267627  PMID: 22187693
Asthma; Endotoxin; Lung function; Rural; Tobacco smoke; Wheeze
6.  Endotoxin as a determinant of asthma and wheeze among rural dwelling children and adolescents: A case–control study 
Background
The association between endotoxin exposure and asthma is complex and has been associated with rural living. We examined the relationship between domestic endotoxin and asthma or wheeze among rural school-aged children (6–18 years) and assessed the interaction between endotoxin and other characteristics with these outcomes.
Methods
Between 2005 and 2007 we conducted a case–control study of children 6–18 years in the rural region of Humboldt, Canada. Cases (n = 102) reported doctor-diagnosed asthma or wheeze in the past year. Controls (n = 208) were randomly selected from children without asthma or wheeze. Data were collected to ascertain symptoms, asthma history and indoor environmental exposures (questionnaire), endotoxin (dust collection from the play area floor and child’s mattress), and tobacco smoke exposure (saliva collection). Statistical testing was completed using multiple logistic regression to account for potential confounders and to assess interaction between risk factors. A stratified analysis was also completed to examine the effect of personal history of allergy.
Results
Among children aged 6–12 years, mattress endotoxin concentration (EU/mg) and load (EU/m2) were inversely associated with being a case [odds ratio (OR) = 0.44, 95% confidence interval (CI) = 0.20-0.98; and OR = 0.38, 95% CI = 0.20-0.75, respectively]. These associations were not observed in older children or with play area endotoxin.
Conclusions
Our results suggest that endotoxin exposure might be protective for asthma or wheeze. The protective effect is found in younger school-aged, non-allergic children. These results may help explain the inconsistencies in previous studies and suggest that the protective effects of endotoxin in the prevention of atopy and asthma or wheeze are most effective earlier in life.
doi:10.1186/1471-2466-12-56
PMCID: PMC3545854  PMID: 22966977
Asthma; Children; Endotoxin; Wheeze; Pediatrics; Allergy
7.  The Saskatchewan rural health study: an application of a population health framework to understand respiratory health outcomes 
BMC Research Notes  2012;5:400.
Background
Respiratory disease can impose a significant burden on the health of rural populations. The Saskatchewan Rural Health Study (SRHS) is a new large prospective cohort study of ages 6 and over currently being conducted in farming and non-farming communities to evaluate potential health determinants associated with respiratory outcomes in rural populations. In this article, we describe the rationale and methodology for the adult component.
The study is being conducted over 5 years (2009–15) in two phases, baseline and longitudinal. The baseline survey consists of two components, adults and children. The adult component consists of a questionnaire-based evaluation of individual and contextual factors of importance to respiratory health in two sub populations (a Farm Cohort and a Small Town Cohort) of rural families in Saskatchewan Rural Municipalities (RMs). Clinical studies of lung function and allergy tests are being conducted on selected sub-samples of the two cohorts based on the positive response to the last question on the baseline questionnaire: “Would you be willing to be contacted about having breathing and/or allergy tests at a nearby location?”. We adopted existing population health theory to evaluate individual factors, contextual factors, and principal covariates on the outcomes of chronic bronchitis, chronic obstructive pulmonary disease, asthma and obstructive sleep apnea.
Findings
Of the RMs selected to participate, 32 (89%) out of 36 RMs and 15 (94%) out of 16 small towns within the RMs agreed to participate. Using the mail out survey method developed by Dillman, we obtained completed questionnaires from 4264 households (8261 individuals). We obtained lung function measurements on 1609 adults, allergy skin test information on 1615 adults; both measurements were available on 1549 adults. We observed differences between farm and non-farm rural residents with respect to individual, contextual factors and covariates.
Discussion
There are differences between farm and non-farm rural residents with respect to individual and contextual factors and other variables of importance. The findings of the SRHS will improve knowledge of respiratory disease etiology, assist in the development and targeting of prevention programs, and in planning health services with farm and small town populations.
doi:10.1186/1756-0500-5-400
PMCID: PMC3438108  PMID: 22852584
Rural; Respiratory; Asthma; Chronic bronchitis; Population health framework; Pulmonary function; Contextual
8.  Pulmonary function in adults with recent and former asthma and the role of sex and atopy 
Background
Pulmonary function is not fully reversible in asthma in children and may continue into adult life. This study was to determine the association between asthma and reduced pulmonary function in adults and the modification by sex and atopic status.
Methods
A cross-sectional study of 1492 adults aged 18 years or over was conducted in a rural community. Atopy, height, weight, waist circumference (WC) and pulmonary function were measured. Participants with ever asthma were those who reported by questionnaire a history of asthma diagnosed by a physician during lifetime. Participants who had former (only) asthma were those who reported having physician-diagnosed asthma more than 12 months ago. Participants who had recent asthma were those who reported having asthma during the last 12 months.
Results
Men had higher values of forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) compared with women, but FEV1/FVC ratio showed no significant difference between sexes. Atopic status was not related to pulmonary function and the average values of the pulmonary function testing variables were almost the same for non-atopic and atopic individuals. Individuals with ever, recent or former asthma had significant lower values of FEV1 and FEV1/FVC ratio than those who reported having no asthma, and the associations tended to be stronger in men than in women. The interaction between atopy and asthma was not statistically significant.
Conclusions
Adults who reported having recent asthma or former asthma had reduced pulmonary function, which was significantly modified by sex but not by atopic status.
doi:10.1186/1471-2466-12-32
PMCID: PMC3461462  PMID: 22748064
Asthma; Atopy; Survey; Lung function; Sex
9.  Predictors of respiratory symptoms in a rural Canadian population: A longitudinal study of respiratory health 
BACKGROUND:
Predictors of new and long-term respiratory symptoms for rural residents are not well defined.
OBJECTIVE:
To identify early predictors of respiratory symptoms in a rural community population.
METHODS:
The study population consisted of 871 adults living in the rural community of Humboldt, Saskatchewan, who participated in two cross-sectional respiratory studies conducted in 1993 and 2003. Questionnaire information obtained at both time points included respiratory symptoms (cough, phlegm and wheeze), history of allergy, smoking, and information regarding home and farm environments. Transitional modelling, in which measurement in a longitudinal sequence is described as a function of previous outcomes, was used to predict later outcomes of cough, phlegm and wheeze. Asymptomatic individuals in 1993 were assessed to determine factors associated with the development of symptoms during the study period.
RESULTS:
The prevalences of cough, phlegm and wheeze in 1993 were 16.1%, 18.1% and 25.5%, respectively. Change in symptoms over time was significant for cough, phlegm and wheeze. The adjusted ORs (95% CI) from separate transitional models for each respiratory outcome in 1993 that predicted the same symptom in 2003 were 6.32 (4.02 to 9.95) for cough, 14.36 (9.01 to 22.89) for phlegm and 6.40 (4.40 to 9.32) for wheeze. For asymptomatic individuals in 1993, home dampness, allergic reaction to inhaled allergens and cigarette smoking were major risk factors associated with respiratory symptoms that were reported in 2003.
CONCLUSION:
The presence of previous respiratory symptoms, allergies and environmental exposures can predict the occurrence of future respiratory symptoms in adults.
PMCID: PMC3328873  PMID: 21766078
Cough; Longitudinal respiratory symptoms; Phlegm; Predictors; Wheeze
10.  A population-based profile of adult Canadians living with participation and activity limitations 
Background:
Currently, one out of every seven Canadians is affected by limitations to their participation and activity. This study describes the self-reported main causes of these limitations in a national sample.
Methods:
The 2006 Participation and Activity Limitation Survey was a two-phase stratified survey based on filter questions posed in the 2006 Census of Population conducted by Statistics Canada. Respondents to the survey represent 5 185 980 Canadian adults with activity and participation limitations. We used these data to develop a profile of our population of interest: adult Canadians with activity and participation limitations. Associations between demographic variables and self-reported causes of activity and participation limitations were assessed using multiple logistic regression.
Results:
One quarter of participants did not attribute their disability to any medical cause. The most prevalent medical conditions to which disabilities were attributed were musculoskeletal (46.1%), cardio/cerebrovascular (12.3%), mental health (8.4%), neurologic (6.0%), endocrine (6.0%) and respiratory (4.5%) conditions. Significant associations were noted between sociodemographic variables and participants’ attributions of medical conditions as cause of disability. Multiple logistic regression with bootstrapping showed that people who reported a medical cause for their limitation were more likely (p < 0.05) to be female, widowed, 40 years of age or older, born in Canada or white and were less likely (p < 0.05) to be in the highest income category or to be employed (i.e., to work more than 0 h/w).
Interpretation:
Most people living with activity and participation limitations report having a musculoskeletal disorder. However, a significant proportion of respondants did not attribute their limitations to a medical cause.
doi:10.1503/cmaj.110153
PMCID: PMC3176864  PMID: 21825051
11.  Allergic rhinitis and genetic components: focus on Toll-like receptors (TLRs) gene polymorphism 
Allergic rhinitis represents a global health issue affecting 10% to 25% of the population worldwide. Over the years, studies have found that allergic diseases, including allergic rhinitis, are associated with immunological responses to antigens driven by a Th2-mediated immune response. Because Toll-like receptors (TLRs) are involved in both innate and adaptive immune responses to a broad variety of antigens, the association between polymorphisms of TLRs and allergic diseases has been the focus in many animal and human studies. Although the etiology of allergic rhinitis is still unknown, extensive research over the years has confirmed that the underlying causes of allergic diseases are due to many genetic and environmental factors, along with the interactions among them, which include gene–environment, gene–gene, and environment–environment interactions. Currently, there is great inconsistency among studies mainly due to differences in genetic background and unique gene–environment interactions. This paper reviews studies focusing on the association between TLR polymorphisms and allergic diseases, including allergic rhinitis, which would help researchers better understand the role of TLR polymorphisms in the development of allergic rhinitis, and ultimately lead to more efficient therapeutic interventions being developed.
doi:10.2147/TACG.S8380
PMCID: PMC3681168  PMID: 23776356
allergic rhinitis; allergic diseases; Toll-like receptors
12.  Fatigue in patients with COPD participating in a pulmonary rehabilitation program 
Background
Fatigue is a distressing, complex, multidimensional sensation common in individuals with chronic obstructive pulmonary disease (COPD). While fatigue negatively impacts functional performance and quality of life, there has been little study of the fatigue that affects participants in pulmonary rehabilitation programs. The purpose of this study was to examine the emotional, behavioral, cognitive, and physical dimensions of fatigue and their relationships to dyspnea, mental health, sleep, and physiologic factors.
Patients and methods
A convenience sample of 42 pulmonary rehabilitation participants with COPD completed self-report questionnaires which measured dimensions of fatigue using the Multidimensional Fatigue Inventory, anxiety and depression using the Hospital Anxiety and Depression Scale, and sleep quality using the Pittsburgh Sleep Quality Index. Data on other clinical variables were abstracted from pulmonary rehabilitation program health records.
Results
Almost all (95.3%) participants experienced high levels of physical fatigue. High levels of fatigue were also reported for the dimensions of reduced activity (88.1%), reduced motivation (83.3%), mental fatigue (69.9%), and general fatigue (54.5%). Close to half (42.9%) of participants reported symptoms of anxiety, while almost one quarter (21.4%) reported depressive symptoms. Age was related to the fatigue dimensions of reduced activity (ρ = 0.43, P < 0.01) and reduced motivation (ρ = 0.31, P < 0.05). Anxiety was related to reduced motivation (ρ = −0.47, P < 0.01). Fatigue was not associated with symptoms of depression, sleep quality, gender, supplemental oxygen use, smoking status, or Medical Research Council dyspnea scores.
Conclusions
Fatigue (particularly the physical and reduced motivation dimensions of fatigue) was experienced by almost all participants with COPD attending this pulmonary rehabilitation program. Fatigue affected greater proportions of participants than either anxiety or depression. The high prevalence of fatigue may impact on enrolment, participation, and attrition in pulmonary rehabilitation programs. Further investigation of the nature, correlates, and impact of fatigue in this population is required.
doi:10.2147/COPD.S12321
PMCID: PMC2962297  PMID: 21037955
COPD; fatigue; pulmonary rehabilitation; anxiety; depression; sleep quality
13.  Factors associated with opioid dispensation for patients with COPD and lung cancer in the last year of life: A retrospective analysis 
Background
For patients in late stages of chronic obstructive pulmonary disease (COPD), dyspnea is often refractory to conventional treatment. We know little about the use of opioids in ameliorating dyspnea in this population. In this study we explored factors associated with opioid dispensation within the last year of life and differences in opioid dispensation for persons with lung cancer or COPD.
Methods
In this retrospective cohort study we used administrative health data gained from 1,035 residents of Saskatchewan, Canada to examine patterns of community opioid dispensation in the last year of life. Factors associated with opioid use were determined using multiple logistic regression.
Results
When compared with those with lung cancer, fewer patients with COPD were given opioids within the last week of life; the last month of life, and the last 3 months of life. After adjusting for relevant predictors, patients with lung cancer were more than twice as likely as those with COPD to fill prescriptions for the following: morphine (odds ratio [OR] 2.36, 95% confidence interval [CI]: 1.52–3.67); hydromorphone (OR 2.69, 95% CI: 1.53–4.72); transdermal fentanyl (OR 2.25, 95% CI: 1.28–3.98); or any of these opioids (OR 2.61, 95% CI: 1.80–3.80).
Conclusion
These opioids are dispensed only for a small proportion of patients with COPD at the end of their lives. Future researchers could explore the efficacy and safety of opioid use for patients with advanced COPD, and whether their limited use is justified.
PMCID: PMC2866560  PMID: 20461142
COPD; lung cancer; dyspnea; opioid dispensation; palliative care
14.  Association of the TLR4 Asp299Gly polymorphism with lung function in relation to body mass index 
Background
Previous studies have shown conflicting results for the association between TLR4 polymorphism (Asp299Gly) and lung function. We investigated the influence of TLR4 Asp299Gly, a polymorphism, on lung function in a community population.
Methods
In 2003, a cross-sectional survey was conducted to assess the respiratory health of residents living in and around the town of Humboldt, Saskatchewan, Canada. There were 2090 adults age 18-79 years who completed a questionnaire that included a medical and smoking history, as well as socio-economic and lifestyle variables. Genetic information and lung function test measurements were available on 1725 subjects (754 males and 971 females) of the 2090 respondents. These subjects were selected for further analysis to investigate the association between TLR4 Asp299Gly genotype and forced expiratory volume in the first second in liters (FEV1), forced vital capacity in liters (FVC), FEV1/FVC ratio, and forced expiratory flow rate in liters/second (FEF25-75). Multivariable linear regression analysis was used to investigate associations.
Results
Adjusted mean values of FEV1 and FVC were significantly different between TLR4 wild type and TLR4 variant groups [Mean ± S.E.: (TLR4 wild type - FEV1: 3.18 ± 0.02, FVC: 3.95 ± 0.03; TLR4 variant - FEV1: 3.31 ± 0.06, FVC: 4.14 ± 0.07)]. Based on multivariable regression analysis, we observed that body mass index (BMI) was associated with decreased FEV1/FVC ratio and FEF25-75 in TLR4 variant group but not in wild type group.
Conclusion
BMI may modify the associations of TLR4 Asp299Gly polymorphism with FEV1/FVC ratio and FEF25-75.
doi:10.1186/1471-2466-9-46
PMCID: PMC2759902  PMID: 19772581

Results 1-14 (14)