Indoor Radon and Lung Cancer: Estimation of Attributable Risk, Disease Burden, and Effects of Mitigation

PURPOSE: Exposure to indoor radon is associated with lung cancer. This study aimed to estimate the number of lung cancer deaths attributable to indoor radon exposure, its burden of disease, and the effects of radon mitigation in Korea in 2010. MATERIALS AND METHODS: Lung cancer deaths due to indoor radon exposure were estimated using exposure-response relations reported in previous studies. Years of life lost (YLLs) were calculated to quantify disease burden in relation to premature deaths. Mitigation effects were examined under scenarios in which all homes with indoor radon concentrations above a specified level were remediated below the level. RESULTS: The estimated number of lung cancer deaths attributable to indoor radon exposure ranged from 1946 to 3863, accounting for 12.5–24.7% of 15623 total lung cancer deaths in 2010. YLLs due to premature deaths were estimated at 43140–101855 years (90–212 years per 100000 population). If all homes with radon levels above 148 Bq/m3 are effectively remediated, 502–732 lung cancer deaths and 10972–18479 YLLs could be prevented. CONCLUSION: These findings suggest that indoor radon exposure contributes considerably to lung cancer, and that reducing indoor radon concentration would be helpful for decreasing the disease burden from lung cancer deaths.

Attributable risk of lung cancer deaths due to indoor radon exposure

Exposure to radon gas is the second most common cause of lung cancer after smoking. A large number of studies have reported that exposure to indoor radon, even at low concentrations, is associated with lung cancer in the general population. This paper reviewed studies from several countries to assess the attributable risk (AR) of lung cancer death due to indoor radon exposure and the effect of radon mitigation thereon. Worldwide, 3–20 % of all lung cancer deaths are likely caused by indoor radon exposure. These values tend to be higher in countries reporting high radon concentrations, which can depend on the estimation method. The estimated number of lung cancer deaths due to radon exposure in several countries varied from 150 to 40,477 annually. In general, the percent ARs were higher among never-smokers than among ever-smokers, whereas much more lung cancer deaths attributable to radon occurred among ever-smokers because of the higher rate of lung cancers among smokers. Regardless of smoking status, the proportion of lung cancer deaths induced by radon was slightly higher among females than males. However, after stratifying populations according to smoking status, the percent ARs were similar between genders. If all homes with radon above 100 Bq/m3 were effectively remediated, studies in Germany and Canada found that 302 and 1704 lung cancer deaths could be prevented each year, respectively. These estimates, however, are subject to varying degrees of uncertainty related to the weakness of the models used and a number of factors influencing indoor radon concentrations.

The Long and Short Incubation Periods of Plasmodium vivax Malaria in Korea: The Characteristics and Relating Factors / 감염과화학요법

BACKGROUND: The cases of Plasmodium vivax malaria in Korea are mixed with long and short incubation periods. This study aims to define clinico-epidemiologic chracteristcs of Plasmodium vivax malaria in Korea. MATERIALS AND METHODS: We selected the civilian cases infected with P. vivax malaria in Korea from the epidemiological investigation data of 2001 to 2010, whose incubation periods could be estimated. The long and short incubation periods were defined by duration of infection and onset time, and the cases were compared by demographic factors and clinical symptom, infection and onset time. The correlation was analyzed between the proportion of cases in the infected region with the long incubation period and meteorological factors along with latitude. RESULTS: The length of the mean short and long incubation periods for the cases were 25.5 days and 329.4 days, respectively. The total number of the study subjects was 897, and the number cases of short and long incubation periods was 575 (64.1%) and 322 (35.9%), respectively. The aspect of incubation period showed a significant difference by region of infection; there was a higher proportion of long incubation period infection cases in Gangwon-do than in Gyeonggi-do and Incheon. The proportion of long incubation period cases showed significant correlation with latitude and temperature of August and September of the infected regions. CONCLUSIONS: Incubation period of P. vivax malaria in Korea showed significant difference by infected region, infection and onset time and the proportion of long incubation period cases showed significant correlation with latitude and meteorological factors of the infected regions.

Characteristics of Summer Heatwave Victims of Emergency Department Visits in Korea During 2011: Results from the Surveillance System of Heat-related Illness Based on Emergency Department

PURPOSE: The aim of this study was to examine characteristics of health-related victims identified through the Surveillance System of Heat-related Illness (SSHI) based on emergency department (ED) visits. METHODS: Between July 1 and September 3 of 2011, 443 heat-related patients were reported by 396 of the 461 EDs participating in the SSHI. Heat-related illness included heat (sun) stroke, heat cramp, heat syncope, and heat exhaustion. A hot day was defined as a day above 30degrees C of daily maximum temperature in locations of provincial and metropolitan government offices. We used chi square test for identification of risk factors associated with Heat-related illness in the workplace and heat-related illness heat (sun) stroke. RESULTS: Heatwave, defined as lasting three or more hot days, occurred three times during this period. The daily average number of heat-related patients reported during the heatwave period was 15.7 per day, more than four times the usual rate. The daily maximum temperature showed positive correlation with occurrence of heat-related illness. Heat exhaustion was the most frequent cause (46.0%), with approximately 70% of all cases occurring between noon and 6 p.m. The number of people suffering from heat-related illness while outdoors was three times greater than that of those who experienced it indoors. Work-related occurrence comprised 56.7% of all cases. All six deaths occurred during the heatwave period and were work-related. CONCLUSION: Working conditions, outdoor activities, and old age may be associated with health-related illnesses. A surveillance system that monitors emergency room visits may be useful in assessment of adverse health effects of summer heatwaves.

Correlations Between Climate Change-Related Infectious Diseases and Meteorological Factors in Korea / 예방의학회지

OBJECTIVES: Infectious diseases are known to be affected by climate change. We investigated if the infectious diseases were related to meteorological factors in Korea. METHODS: Scrub typhus, hemorrhagic fever with renal syndrome (HFRS), leptospirosis, malaria and Vibrio vulnificus sepsis among the National Notifiable Infectious Diseases were selected as the climate change-related infectious diseases. Temperature, relative humidity and precipitation were used as meteorological factors. The study period was from 2001 through 2008. We examined the seasonality of the diseases and those correlations with meteorological factors. We also analyzed the correlations between the incidences of the diseases during the outbreak periods and monthly meteorological factors in the hyper-endemic regions. RESULTS: All of the investigated diseases showed strong seasonality; malaria and V. vulnificus sepsis were prevalent in summer and scrub typhus, HFRS and leptospirosis were prevalent in the autumn. There were significant correlations between the monthly numbers of cases and all the meteorological factors for malaria and V. vulnificus sepsis, but there were no correlation for the other diseases. However, the incidence of scrub typhus in hyper-endemic region during the outbreak period was positively correlated with temperature and humidity during the summer. The incidences of HFRS and leptospirosis had positive correlations with precipitation in November and temperature and humidity in February, respectively. V. vulnificus sepsis showed positive correlations with precipitation in April/May/July. CONCLUSIONS: In Korea, the incidences of the infectious diseases were correlated with meteorological factors, and this implies that the incidences could be influenced by climate change.

Lifestyle Recommendations for Dementia Prevention: PASCAL

The increasing number of persons with dementia poses a serious threat to public health in an aging society. Efforts to curb the rising prevalence of dementia have directed attention to health promotion as a viable strategy for delaying dementia onset and maintaining cognitive function in later life. For the latter purpose, public recommendations were developed based on a systematic review of the literature. Significant lifestyle variables found to predict cognitive function and dementia in later life were physical activity, non-smoking, social activity, cognitive activity, moderate alcohol consumption, normal body weight (BMI), and healthy nutrition and diet (fish, vegetables, fruits, vitamin C and E, etc.). Cognitive health recommendations were developed and named PASCAL, an acronym for (1) Physical activity, (2) Anti-smoking, (3) Social activity, (4) Cognitive activity, (5) Alcohol drinking in moderation, and (6) Lean body mass and healthy diet. These recommendations can be used to educate the public and raise awareness in health professionals to the important role a healthy lifestyle plays in maintaining cognitive health in later life.