County level incidence rates of chronic lymphocytic leukemia are associated with residential radon levels

Epidemiology of Chronic Lymphocytic Leukemia in Sardinia, Italy (1974-2003)

Several reports have described a worldwide increasing incidence of chronic lymphocytic leukemia (CLL) dating back seven to eight decades. Although genetic susceptibility would be an implausible explanation, the determinants of this upward trend and its spatial coordinates are poorly understood. We explored CLL incidence in Sardinia, Italy, using a validated database including the 1700 CLL cases diagnosed during 1974-2003. We applied Bayesian methods to map the CLL probability by administrative unit and Poisson regression analysis to investigate socioeconomic and environmental determinants adjusting by possible confounders. The standardized (Standard European population) incidence rate for the Sardinian population over the study period was 5.1 per 100,000 (95% confidence interval [CI] 4.9-5.3), increased annually by 5.8% (95% CI 5.7-6.0) consistently by sex and age, and was more noticeable in urban areas. Five administrative units exceeded the 95% posterior probability of an elevated CLL incidence: these were rural areas spread over the regional territory, not suggestive of spatial clustering. The Poisson regression analysis showed that the risk was elevated in urban areas (RR = 1.11, 95% CI 1.05-1.17), among residents ≥ 30 km from the nearest hospital (RR = 1.09, 95% CI 1.06-1.12), and with the local prevalence of cork harvesting (RR = 1.62, 95% CI 1.12-2.34). Our results suggest that better access to health care facilities and improvements in diagnostic efficacy might have generated the observed upward trend in CLL incidence, along with contributing environmental factors.

Association of MTHFR C677T and A1298C Polymorphisms with Susceptibility to Chronic Lymphocytic Leukemia: A Systematic Review and Meta-Analysis

Background:

The relation between methylenetetrahydrofolate reductase)MTHFR(polymorphisms and the risk of developing Chronic lymphocytic leukemia (CLL) is not still clear, while there are reports about the association of MTHFR C677T and A1298C polymorphisms with developing CLL, there are other reports that rolled out the association of MTHFR polymorphisms with developing CLL. Therefore herein we carried out this meta-analysis to clear the association of MTHFR polymorphisms with the risk of CLL,

Methods:

A comprehensive search was performed through PubMed, Scopus and Embase from inception to Aug 2020. Odds ratios (OR) with their corresponding 95% confidence intervals (CI) for five possible genetic models were calculated. Heterogeneity was evaluated using the Cochran Q test and the I2 statistic.

Results:

Totals of 1290 cases and 1887 controls for the C677T polymorphism and 1117 cases and 1256 controls for the A1298C polymorphism were included in our analysis. Analyzing the MTHFR C677T and A1298C polymorphisms genotypes showed an association between MTHFR polymorphism at A1298C under Allelic model and the risk of CLL (OR = 1.12, 95% CI = 1.01–1.25), however there was no association between MTHFR polymorphism at MTHFR C677T and risk of CLL.

Conclusion:

The risk of developing CLL might be associated with MTHFR polymorphism at A1298C under allelic model and not associated with MTHFR polymorphisms at C677T, However, further studies considering other factors such as age, gender, ethnicity, gene-gene interaction and environmental condition are needed to clear the true association of MTHFR polymorphisms with CLL.

Communicating radon risk via a smartphone app: a pilot intervention study

Background

Residential radon is a major preventable cause of lung cancer. However, prevention requires radon testing and it has proven very challenging to motivate individuals to test their homes for hazards like radon that are invisible and whose health effects occur after a long latency following exposure. Novel approaches to radon communication are urgently needed.

Methods

We created a novel radon-education app for smartphones and examined its effectiveness in increasing radon knowledge and radon testing. We studied radon knowledge and attitudes and behavior relevant to radon testing before and after app use.

Results

Ninety-seven undergraduates installed the app on their smartphones and used it for a month. App use resulted in higher scores in the domains of radon knowledge (p < .001); self-efficacy (p < .001), and response efficacy (p < .001). Twenty-three participants (24%) used the app to obtain a free radon test kit. Self-efficacy (p < .05) and response efficacy (p < .01) were positive predictors of ordering a test kit. The test process completion rate (the fraction of participants who ordered test kits, used them to test their houses and sent the kits to the lab) was 9%.

Conclusions

A smartphone app is a promising venue for communicating radon risk and for stimulating radon testing. Future interventions designed to increase actual test kit use are required to maximize the benefit of the app.

Thyroid Cancer Incidence Rates in North Dakota are Associated with Land and Water Use

Objective: The increasing rate of thyroid cancer diagnoses in the U.S. reflects the increasing use of ultrasonography and of specialist medical care. North Dakota is a rural state with limited access to specialist care, yet its incidence of thyroid cancer is significantly greater than that of the U.S. overall. We sought to identify factors responsible for the high incidence of thyroid cancer in North Dakota. Methods: We examined county-specific incidence rates for thyroid cancer in North Dakota in relation to demographic and geographic factors, including median household income, percent of land fertilized, cattle density per capita, and source of drinking water (city or well water), using structural equation modeling. We included county level data on residential radon levels and estimates of radioactive iodine in milk following nuclear weapons testing in the 1950s. Results: Thyroid cancer incidence rates were significantly associated with median income (p < 0.05); percent of land fertilized (p < 0.05); the use of city water (p < 0.01), and cattle density per capita (p < 0.001). Conclusions: The risk of thyroid cancer in North Dakota is positively associated with income and with factors related to land and water use. Our finding that thyroid cancer incidence rates are associated with the use of city water was unexpected and merits examination in other locations with a mix of city and well water use.

An exploration of colorectal cancer incidence rates in North Dakota, USA, via structural equation modeling

PURPOSE

The state of North Dakota has one of the highest incidence rates for colorectal cancer in the USA. Its high incidence rate, coupled with a large variation in incidence rates among counties within the state, makes North Dakota a "natural laboratory" in which to investigate environmental clues to colorectal cancer. We conducted a hypothesis-generating study to explore potential determinants of colorectal cancer in North Dakota.

METHODS

We obtained county-specific incidence rates for North Dakota's 53 counties from the statewide cancer registry and corresponding data on county demographic, agricultural, and geophysical features from population-based sources. Candidate demographic/agricultural variables included median household income, population density, colorectal cancer screening rates, average farm size (in acres), and the percent of county fertilized. Geophysical variables included the uranium content of soil, residential radon levels, and source of drinking water (municipal or well water). Statistical analyses were performed via multivariate regression and structural equation modeling.

RESULTS

Colorectal cancer incidence rates across North Dakota counties varied 3-fold. The structural equation model identified a significant role for well water use (p < 0.05). This finding is consistent with studies that implicate well water in colorectal cancer.

CONCLUSIONS

Well water contains several agents, e.g., bacteria, disinfection by-products, and nitrates that are potent colorectal carcinogens. Studies of well water use and colorectal cancer risk at the individual level in North Dakota are warranted.

Preliminary Indoor Radon Measurements Near Faults Crossing Urban Areas of Mt. Etna Volcano (Italy)

The slopes of Etna are crossed by numerous active faults that traverse various towns and villages. These faults pose a two-fold problem for the local people: on one hand, they cause frequent damage to houses and breakage of roads, while on the other they constitute a preferential route for the rising of crustal and sub-crustal gases, including radon, toward the surface. Various recent studies on the volcano confirm a high level of radon degassing measured both in the soil (> 10,000 Bq/m³), and inside homes (> 2,000 Bq/m³). For this reason, we felt the need to deepen our knowledge on the radon present in the Etnean area, focusing in particular on indoor radon pollution that, as widely recognized, is among the main causes of cancer largely (but not exclusively) of the respiratory system. Firstly, since 2005 we made a broad surface survey that revealed very high radon emissions from soils near active faults on Etna. Typical background soil activity on Etna were <1,000 Bq/m³, whereas in areas of stronger soil degassing, activity values up to ~60,000 Bq/m³ were measured. Furthermore, since late 2015 we have performed continuous indoor radon monitoring inside seven houses, some of which located close to degassing faults on the eastern, southern and south-western flanks of the volcano. Indoor radon concentration varied according to the season of the year, but above all, they changed according to the geology and tectonic setting of the substratum of the monitored houses. In one case, indoor radon concentration reached 3,549 Bq/m³ and remained > 1,000 Bq/m³ for several consecutive months, highlighting a potential health problem for those living in such environments. In other cases, the construction features of the houses and/or the materials used seemed to play an important role in the mitigation of indoor radon accumulation, even in the presence of intensely degassing soils. These preliminary data demonstrate the need to deepen the studies, extending indoor radon measurements to other urban areas, in order to monitor the health hazard for the Etna population, amounting to about one million people.