The relation of environmental tobacco smoke (ETS) to chronic bronchitis and mortality over two decades.

INTRODUCTION: Our aim was to describe how the prevalence of subjects exposed to environmental tobacco smoke (ETS) has changed from 1992 to 2012 in Finland. We also investigated the association between ETS and chronic bronchitis and cause-specific and all-cause mortality. METHODS: The study population is composed of 38 494 subjects aged 25-74 years who participated in the National FINRISK Study between 1992 and 2012. Each survey included a standardized questionnaire on exposure to ETS, symptoms of chronic bronchitis, smoking habits and other risk factors, and clinical measurements at the study site. Data on mortality was obtained from the National Causes of Death Register. RESULTS: In 2012, 5% of the participants were exposed to ETS compared to 25% in 1992. The adjusted odds ratio (OR) for ETS exposure in 2012 compared with that in 1992 was 0.27, p < 0.001. Exposure to ETS was more common in men than in women and among smokers than in non-smokers. Exposure to ETS was in turn associated with chronic bronchitis, OR 1.63 (95% confidence interval 1.49-1.78), - also separately both at work (OR 1.36) and at home (OR 1.69). Subjects with exposure to ETS had significantly increased all-cause (hazard ratio = HR 1.15, 1.05-1.26) and cardiovascular mortality (HR 1.26, 1.07-1.47). However, when stratified by smoking ETS was associated with all-cause mortality only in smokers (HR 1.31, 1.15-1.48). CONCLUSION: The proportion of subjects exposed to ETS decreased substantially during the study. Additionally, ETS exposure was associated with chronic bronchitis throughout the study and increased all-cause and cardiovascular mortality.

30-year trends in asthma and the trends in relation to hospitalization and mortality.

INTRODUCTION: The present study examines how trends in the prevalence of asthma during the past three decades associate with hospitalization and mortality during the same period. METHODS: Altogether 54 320 subjects aged 25-74 years were examined in seven independent cross-sectional population surveys repeated every five years between 1982 and 2012 in Finland. The study protocol included a standardized questionnaire on self-reported asthma, smoking habits and other risk factors, and clinical measurements at the study site. Data on hospitalizations were obtained from the Care Register for Health Care, and data on mortality from the National Causes of Death register. RESULTS: During the study, the prevalence of asthma increased - especially in women. In asthmatic compared with non-asthmatic subjects, hospitalization was significantly higher for all causes, respiratory causes, cardiovascular causes and lung cancer. In addition, particularly in asthmatic subjects, mean yearly hospital days in the 5-year periods after each survey diminished. In asthmatic subjects, the decrease in yearly all-cause hospital days was from 4.45 (between 1982 and 1987) to 1.11 (between 2012 and 2015) and in subjects without asthma the corresponding decrease was from 1.77 to 0.60 (p < 0.001). Similarly between 1982 and 2015, COPD hospitalization decreased more in asthmatic than in non-asthmatic subjects. Generally in the present study, all-cause mortality decreased between 1982 and 2015, though mortality in asthmatic subjects compared with non-asthmatics was higher from all causes, respiratory causes and lung cancer. CONCLUSION: There was an increasing trend in the prevalence of asthma and a declining trend in hospitalization, especially in asthmatic subjects.

Chronic bronchitis in relation to hospitalization and mortality over three decades.

BACKGROUND: The study examines the predictive value of chronic bronchitis for all cause and cause-specific hospitalizations and for mortality during the last three decades. METHODS: The study population consists of altogether 47 896 men and women aged 25-74 years who participated in the National FINRISK Study between 1982 and 2007. The study protocol included a standardized questionnaire on the symptoms of chronic bronchitis, smoking habits and other risk factors and clinical measurements at the study site. Data on hospitalizations were obtained from the National Hospital Discharge Registry, and data on the underlying causes of deaths from the National Causes of Death register. The study cohorts were followed up until the end of 2011. RESULTS: In study subjects with symptoms of chronic bronchitis the mean annual days of hospitalization were almost two-fold higher than in study subjects without chronic bronchitis. The increase was seen in all age -groups and both in 5-year periods for each cohort and during the whole 30-year follow-up. More specifically, hospitalizations were increased for respiratory diseases and cancer. Chronic bronchitis increased hospitalizations more in smokers and ex-smokers than in never smokers. Furthermore, chronic bronchitis was associated with increased all-cause mortality (hazard ratio (HR) 1.23) and mortality from respiratory causes, cardiovascular diseases and cancer. Smokers and ex-smokers with chronic bronchitis had an increased risk to die (HRs 2.89 and 1.69, respectively) compared with never-smokers without chronic bronchitis. CONCLUSION: Symptoms of chronic bronchitis can help to identify individuals who are at risk for increased hospitalizations and mortality.

Twenty-five year trends in prevalence of chronic bronchitis and the trends in relation to smoking.

INTRODUCTION: The present study examines how the trends in the prevalence of chronic bronchitis during the last three decades associate with changes in smoking habits during the same period. METHODS: Altogether 47 896 subjects aged 25-74 years were examined in six independent cross-sectional population surveys repeated every five years between 1982 and 2007 in Finland. The presence of chronic bronchitis, smoking habits and other risk factors were measured by standard questionnaires. RESULTS: During the study, the prevalence of chronic bronchitis was significantly higher in men than in women. In men aged 25-64 years, the prevalence of chronic bronchitis decreased from 19% in 1982 to 13% in 2007 (p for trend <0.001). The corresponding decrease in women aged 25-64 years was from 13% to 11% (p for trend 0.009). In men aged 65-74 years, the prevalence of chronic bronchitis decreased from 24% to 19% (p for trend 0.032). Simultaneously, male smoking decreased and smoking in middle-aged women increased. However, adjusting for the changes in smoking habits did not change the declining trends in the prevalence of chronic bronchitis. The significant declining trend in chronic bronchitis was seen separately in male current smokers and in male and female never smokers aged 45-74 years and the declining trend was the greatest in male current smokers. In general, female smokers with chronic bronchitis had smoked less than their male counterparts. CONCLUSION: There was a declining trend in the prevalence of chronic bronchitis which was probably explained by both a decrease in smoking and by other factors.