Cannabis smoking and lung cancer risk: Pooled analysis in the International Lung Cancer Consortium.

To investigate the association between cannabis smoking and lung cancer risk, data on 2,159 lung cancer cases and 2,985 controls were pooled from 6 case-control studies in the US, Canada, UK, and New Zealand within the International Lung Cancer Consortium. Study-specific associations between cannabis smoking and lung cancer were estimated using unconditional logistic regression adjusting for sociodemographic factors, tobacco smoking status and pack-years; odds-ratio estimates were pooled using random effects models. Subgroup analyses were done for sex, histology and tobacco smoking status. The shapes of dose-response associations were examined using restricted cubic spline regression. The overall pooled OR for habitual versus nonhabitual or never users was 0.96 (95% CI: 0.66-1.38). Compared to nonhabitual or never users, the summary OR was 0.88 (95%CI: 0.63-1.24) for individuals who smoked 1 or more joint-equivalents of cannabis per day and 0.94 (95%CI: 0.67-1.32) for those consumed at least 10 joint-years. For adenocarcinoma cases the ORs were 1.73 (95%CI: 0.75-4.00) and 1.74 (95%CI: 0.85-3.55), respectively. However, no association was found for the squamous cell carcinoma based on small numbers. Weak associations between cannabis smoking and lung cancer were observed in never tobacco smokers. Spline modeling indicated a weak positive monotonic association between cumulative cannabis use and lung cancer, but precision was low at high exposure levels. Results from our pooled analyses provide little evidence for an increased risk of lung cancer among habitual or long-term cannabis smokers, although the possibility of potential adverse effect for heavy consumption cannot be excluded.

The association of material deprivation component measures with injury hospital separations in British Columbia, Canada.

BACKGROUND: This study examines social disparities across neighbourhood levels of income, education and employment in relation to overall injury hospital separations in the province of British Columbia, Canada. Further, the study examines the relationships of social disparities to a set of three injury prevention priorities in British Columbia, namely, transport (motor vehicle occupant, pedestrian and cyclist), falls among older adults, and youth self-harm. The goal being to better understand area-based injury incidence with a view to precision prevention initiatives, particularly for more vulnerable populations. METHODS: Acute hospital separations from the Discharge Abstract Database were identified for all causes of injury and the three BC injury prevention priorities for the period April 1, 2009 to March 31, 2014, inclusive. An ecological approach was applied where each hospital separation case was attributed with the income, education and employment level according to the injured individual's area of residence, derived from the 2011 CensusPlus data. RESULTS: Injury hospital separation data were available for 191 Forward Sortation Areas in BC. Between April 1, 2009 and March 31, 2014, there was a total of 177,861 injury-related hospital separations, averaging 35,572 hospital separations per year and an annual rate of 779 injury hospital separations per 100,000 population. Injury hospital separation rates varied with the measured neighbourhood area socioeconomic status variables. Injury hospital separation rates demonstrated an inverse relationship with neighbourhood levels of income and education. Neighbourhood area socioeconomic status differences were also associated with the injury hospital separation rates for falls among older adults, motor vehicle crashes involving motor vehicle occupants, pedestrians, cyclists and young drivers, and youth self-harm. CONCLUSIONS: The study results show that neighbourhood levels of income, education and employment are associated with the risk of injury hospital separation. In particular, low education levels in FSAs was associated with increased risk of injury hospital separation, mainly for motor vehicle occupants, pedestrians, young drivers, and youth self-harm. The results of this study provide useful information for implementing injury prevention initiatives and interventions in BC to align with the provincial public health system and road safety strategy goals, particularly for identified priorities.

Area-based socioeconomic disparities in mortality due to unintentional injury and youth suicide in British Columbia, 2009-2013. / Disparités socioéconomiques et spatiales dans les décès attribuables au suicide chez les jeunes et aux blessures non intentionnelles en Colombie-Britannique (2009-2013).

INTRODUCTION: The association between health outcomes and socioeconomic status (SES) has been widely documented, and mortality due to unintentional injuries continues to rank among the leading causes of death among British Columbians. This paper quantified the SES-related disparities in the mortality burden of three British Columbia's provincial injury prevention priority areas: falls among seniors, transport injury, and youth suicide. METHODS: Mortality data (2009 to 2013) from Vital Statistics and dissemination area or local health area level socioeconomic data from CensusPlus 2011 were linked to examine age-standardized mortality rates (ASMRs) and disparities in ASMRs of unintentional injuries and subtypes including falls among seniors (aged 65+) and transport-related injuries as well as the intentional injury type of youth suicide (aged 15 to 24). Disparities by sex and geography were examined, and relative and absolute disparities were calculated between the least and most privileged areas based on income, education, employment, material deprivation, and social deprivation quintiles. RESULTS: Our study highlighted significant sex differences in the mortality burden of falls among seniors, transport injury, and youth suicide with males experiencing significantly higher mortality rates. Notable geographic variations in overall unintentional injury ASMR were also observed across the province. In general, people living in areas with lower income and higher levels of material deprivation had increasingly higher mortality rates compared to their counterparts living in more privileged areas. CONCLUSION: The significant differences in unintentional and intentional injury-related mortality outcomes between the sexes and by SES present opportunities for targeted prevention strategies that address the disparities.

Life expectancy ranking of Canadians among the populations in selected OECD countries and its disparities among British Columbians.

BACKGROUND: Canada is among the world's leading nations with the longest life expectancy at birth (LE0), and British Columbia (BC) ranks top among Canadian provinces and territories for LE0 in both men and women. This paper examined recent data as well as projected trends in LE0 of Canadian men and women and explored the geographic and socioeconomic disparities in LE0 specific to BC. METHODS: Using retrospective data on LE0 and age-standardized mortality rates, Canada was compared to 11 other Organization for Economic Cooperation and Development (OECD) countries with the longest LE0. Projections were made using linear regression modelling to the year of 2023. The association between regional LE0 and regional socioeconomic status (SES) was examined for the province of BC using its Local Health Area (LHA) level data on SES and LE0. RESULTS: In 2009, Canadian men (LE0: 78.7 years) and women (LE0: 83.3 years) ranked 7(th) and 8(th), respectively among the 12 OECD nations under comparison. Significantly smaller annual gains in LE0 contributed to the losing of their top ranks in LE0 for Canadian men and women in recent years, which was projected to sustain. Higher mortality risks, particularly for lung cancer and external causes of mortality among women was found for Canada compared to leading countries on these measures. Geographic variations were evident in LE0 in BC, and there was a significant gap of 3.6 years in the average LE0 for BC's LHAs in the lowest SES tertile (78.6 years, 95% CI: 78.0-79.3) compared to those in the highest SES tertile (82.2 years, 95% CI: 81.6-82.8). CONCLUSIONS: Canada continues to remain one of the OECD countries with longest living population. With the highest LE0 in the country, British Columbia has an opportunity to address socio-economic disparities in LE0.

Vitamin and mineral supplements and thyroid cancer: a systematic review.

The purpose of this study was to consolidate epidemiological evidence for the association between dietary supplements of vitamins and minerals and thyroid cancer development, as well as to contribute to evidence-based dietary recommendations for thyroid cancer primary prevention. We carried out a systematic literature review specifically for dietary supplement and thyroid cancer risk. MEDLINE, EMBASE, and Dissertations and Theses were systematically searched to identify original epidemiological studies with a comparison group that investigated vitamin or mineral supplementation as an etiological factor for thyroid cancer. In total, 11 independent studies were identified and reviewed. Our qualitative summary showed conflicting results for common antioxidants including vitamins A, C, and E and ß-carotene in relation to thyroid cancer. Similarly, results for dietary supplement combinations as well as other individual vitamins and minerals (vitamin B complex, vitamin D, iodine, calcium, zinc, magnesium, and iron) are largely inconsistent across studies. Overall, our review suggested that the current evidence to support any protective or hazardous effect of vitamin or mineral supplements on thyroid cancer development is inconclusive and additional studies addressing previous limitations are necessary to elucidate this possible association. In particular, reverse causality is of major concern and should be addressed by prospective studies with large and representative samples.

Worry is good for breast cancer screening: a study of female relatives from the ontario site of the breast cancer family registry.

Background. Few prospective studies have examined associations between breast cancer worry and screening behaviours in women with elevated breast cancer risks based on family history. Methods. This study included 901 high familial risk women, aged 23-71 years, from the Ontario site of the Breast Cancer Family Registry. Self-reported breast screening behaviours at year-one followup were compared between women at low (N = 305), medium (N = 433), and high (N = 163) levels of baseline breast cancer worry using logistic regression. Nonlinear relationships were assessed using likelihood ratio tests. Results. A significant non-linear inverted "U" relationship was observed between breast cancer worry and mammography screening (P = 0.034) for all women, where women at either low or high worry levels were less likely than those at medium to have a screening mammogram. A similar significant non-linear inverted "U" relationship was also found among all women and women at low familial risk for worry and screening clinical breast examinations (CBEs). Conclusions. Medium levels of cancer worries predicted higher rates of screening mammography and CBE among high-risk women.

Influence of perceived breast cancer risk on screening behaviors of female relatives from the Ontario site of the Breast Cancer Family Registry.

Few studies have examined the influence of perceived risk on breast screening behaviors among women with an increased familial breast cancer risk. This study included 1019 women aged 20-71 years from the Ontario site of the Breast Cancer Family Registry who had at least one first-degree relative diagnosed with breast and/or ovarian cancer. Information was obtained from a self-administered questionnaire completed at the time of recruitment and a follow-up telephone questionnaire. The associations between breast screening behaviors and perceived risk of developing breast cancer, measured on both a numerical and Likert-type verbal scale, were estimated using logistic regression analyses. Women who rated their risk of developing breast cancer as greater than 50% compared with less than 50% were significantly more likely to have a screening mammogram within the last 12 months (odds ratio: 1.91; 95% confidence interval: 1.15-3.16). Women were significantly more likely to have a screening mammogram (odds ratio: 1.82; 95% confidence interval: 1.17-2.81) in the past 12 months if they rated their risk as above or much above average compared with same as average or below. These findings may inform educational messages for improving risk communication of women at elevated familial breast cancer risk.