Young Adult and Usual Adult Body Mass Index and Multiple Myeloma Risk: A Pooled Analysis in the International Multiple Myeloma Consortium (IMMC).

Background: Multiple myeloma risk increases with higher adult body mass index (BMI). Emerging evidence also supports an association of young adult BMI with multiple myeloma. We undertook a pooled analysis of eight case-control studies to further evaluate anthropometric multiple myeloma risk factors, including young adult BMI.Methods: We conducted multivariable logistic regression analysis of usual adult anthropometric measures of 2,318 multiple myeloma cases and 9,609 controls, and of young adult BMI (age 25 or 30 years) for 1,164 cases and 3,629 controls.Results: In the pooled sample, multiple myeloma risk was positively associated with usual adult BMI; risk increased 9% per 5-kg/m2 increase in BMI [OR, 1.09; 95% confidence interval (CI), 1.04-1.14; P = 0.007]. We observed significant heterogeneity by study design (P = 0.04), noting the BMI-multiple myeloma association only for population-based studies (Ptrend = 0.0003). Young adult BMI was also positively associated with multiple myeloma (per 5-kg/m2; OR, 1.2; 95% CI, 1.1-1.3; P = 0.0002). Furthermore, we observed strong evidence of interaction between younger and usual adult BMI (Pinteraction <0.0001); we noted statistically significant associations with multiple myeloma for persons overweight (25-<30 kg/m2) or obese (30+ kg/m2) in both younger and usual adulthood (vs. individuals consistently <25 kg/m2), but not for those overweight or obese at only one time period.Conclusions: BMI-associated increases in multiple myeloma risk were highest for individuals who were overweight or obese throughout adulthood.Impact: These findings provide the strongest evidence to date that earlier and later adult BMI may increase multiple myeloma risk and suggest that healthy BMI maintenance throughout life may confer an added benefit of multiple myeloma prevention. Cancer Epidemiol Biomarkers Prev; 26(6); 876-85. ©2017 AACR.

A pooled analysis of cigarette smoking and risk of multiple myeloma from the international multiple myeloma consortium.

BACKGROUND: Past investigations of cigarette smoking and multiple myeloma have been underpowered to detect moderate associations, particularly within subgroups. To clarify this association, we conducted a pooled analysis of nine case-control studies in the International Multiple Myeloma Consortium, with individual-level questionnaire data on cigarette smoking history and other covariates. METHODS: Using a pooled population of 2,670 cases and 11,913 controls, we computed odds ratios (OR) and 95% confidence intervals (CI) relating smoking to multiple myeloma risk using unconditional logistic regression adjusting for gender, age group, race, education, body mass index, alcohol consumption, and study center. RESULTS: Neither ever smokers (OR, 0.95; 95% CI, 0.87-1.05), current smokers (OR, 0.82; 95% CI, 0.73-0.93), nor former smokers (OR, 1.03; 95% CI, 0.92-1.14) had increased risks of multiple myeloma compared with never smokers. Analyses of smoking frequency, pack-years, and duration did not reveal significant or consistent patterns, and there was no significant effect modification by subgroups. CONCLUSION: Findings from this large pooled analysis do not support the hypothesis of cigarette smoking as a causal factor for multiple myeloma. IMPACT: Cigarette smoking is one of the most important risk factors for cancer, but the association with multiple myeloma was inconclusive. This study had excellent power to detect modest associations, and had individual-level data to evaluate confounding and effect modification by potentially important factors that were not evaluated in previous studies. Our findings confirm that smoking is not a risk factor for multiple myeloma. Cancer Epidemiol Biomarkers Prev; 24(3); 631-4. ©2014 AACR.

A pooled analysis of alcohol consumption and risk of multiple myeloma in the international multiple myeloma consortium.

BACKGROUND: Recent findings suggest that alcohol consumption may reduce risk of multiple myeloma. METHODS: To better understand this relationship, we conducted an analysis of six case-control studies participating in the International Multiple Myeloma Consortium (1,567 cases, 7,296 controls). Summary ORs and 95% confidence intervals (CI) relating different measures of alcohol consumption and multiple myeloma risk were computed by unconditional logistic regression with adjustment for age, race, and study center. RESULTS: Cases were significantly less likely than controls to report ever drinking alcohol (men: OR = 0.72; 95% CI, 0.59-0.89; women: OR = 0.81; 95% CI, 0.68-0.95). The inverse association with multiple myeloma was stronger when comparing current to never drinkers (men: OR = 0.57; 95% CI, 0.45-0.72; women: OR = 0.55; 95% CI, 0.45-0.68), but null among former drinkers. We did not observe an exposure-response relationship with increasing alcohol frequency, duration, or cumulative lifetime consumption. Additional adjustment for body mass index, education, or smoking did not affect our results; and the patterns of association were similar for each type of alcohol beverage examined. CONCLUSIONS: Our study is, to our knowledge, the largest of its kind to date, and our findings suggest that alcohol consumption may be associated with reduced risk of multiple myeloma. IMPACT: Prospective studies, especially those conducted as pooled analyses with large sample sizes, are needed to confirm our findings and further explore whether alcohol consumption provides true biologic protection against this rare, highly fatal malignancy.

Cannabis smoking and risk of lung cancer in men: a pooled analysis of three studies in Maghreb.

BACKGROUND: Cannabis is the most widely consumed illicit drug worldwide and the relation between cannabis smoking and lung cancer is suggestive, albeit inconclusive. METHOD: We conducted three hospital based case-control studies in Tunisia, Morocco, and Algeria, three areas of high prevalence of cannabis consumption as well as production. This paper presents the pooled analysis of these three studies restricted to men with a total of 430 cases and 778 controls. RESULTS: Ninety-six percent of the cases and 67.8% of the controls were tobacco smokers and 15.3% of the cases and 5% of the controls were ever cannabis smokers. All cannabis smokers were tobacco users. Adjusting for country, age, tobacco smoking, and occupational exposure, the odds ratio (OR) for lung cancer was 2.4 (95% confidence interval [CI]: 1.6-3.8) for ever cannabis smoking. This association remained after adjustment for lifetime tobacco packyears as continuous variable, OR = 2.3 (95% CI: 1.5-3.6). The OR adjusted for intensity of tobacco smoking (cigarette/d) among current tobacco smokers and never cannabis smokers was 10.9 (95% CI: 6.0-19.7) and the OR among current tobacco users and ever cannabis smokers was 18.2 (95% CI: 8.0-41.0). The risk of lung cancer increased with increasing joint-years, but not with increasing dose or duration of cannabis smoking. CONCLUSION: Our results suggest that cannabis smoking may be a risk factor for lung cancer. However, residual confounding by tobacco smoking or other potential confounders may explain part of the increased risk.

Occupational exposure to meat and risk of lymphoma: a multicenter case-control study from Europe.

Several studies have suggested an increased risk of lymphoma among workers exposed to meat, without conclusive evidence. We conducted a multicenter case-control study during 1998-2004 in the Czech Republic, France, Germany, Ireland, Italy and Spain, including 2,007 cases of non-Hodgkin lymphoma, 339 cases of Hodgkin lymphoma and 2,462 controls. We collected detailed information on occupational history and assessed exposure to meat in general and several types of meat via expert assessment of the questionnaires. The odds ratio (OR) of non-Hodgkin lymphoma for ever occupational exposure to meat was 1.18 (95% confidence interval [CI] 0.95-1.46), that for exposure to beef meat was 1.22 (95% CI 0.90-1.67), and that for exposure to chicken meat was 1.19 (95% CI 0.91-1.55). The ORs were higher among workers with longer duration of exposure. An increased risk among workers exposed to beef meat was mainly apparent for diffuse large B-cell lymphoma (OR 1.49, 95%CI 0.96-2.33), chronic lymphocytic leukemia (OR 1.35, 95% CI 0.78-2.34) and multiple myeloma (OR 1.40, 95%CI 0.67-2.94). The latter 2 types were also associated with exposure to chicken meat (OR 1.55, 95% CI 1.01-2.37, and OR 2.05, 95%CI 1.14-3.69). Follicular lymphoma and T-cell lymphoma, as well as Hodgkin lymphoma did not show any increase in risk. Occupational exposure to meat does not appear to represent an important risk factor of lymphoma, although an increased risk of specific types of non-Hodgkin lymphoma cannot be excluded.

Risk of lung cancer and past use of cannabis in Tunisia.

The association between the use of cannabis and the risk of lung cancer is unclear. A hospital-based case-control study was conducted among men in Tunisia and included 149 incident lung cancer cases and 188 controls. Tobacco smoking was significantly associated with an increased risk of lung cancer with odds ratios increasing linearly (p for trend < 0.0001) from 3.9 (95% confidence interval [CI], 1.4-10.9) for former smokers to 17.1 (95% CI: 6.3-46.3) among current smokers who had smoked for >35 years. The odds ratio for the past use of cannabis and lung cancer was 4.1 (95% CI: 1.9-9.0) after adjustment for age, tobacco use, and occupational exposures. No clear dose-response relationship was observed between the risk of lung cancer and the intensity or duration of cannabis use. This study suggests that smoking cannabis may be a risk factor for lung cancer.

A case-control study of lung cancer in Casablanca, Morocco.

OBJECTIVE: To evaluate etiologic risk factors for lung cancer in Casablanca, Morocco. METHODS: We conducted a hospital-based case-control study that included 118 incident lung cancer cases and 235 age-, sex- and residence-matched controls. We analyzed the data using matched univariate and matched and unmatched multivariate logistic regression analyses. RESULTS: Active tobacco smoking and history of chronic bronchitis were the strongest risk factors for lung cancer in the matched logistic regression model. Multivariate odds ratio (OR) and 95% confidence intervals varied from 1.79 (0.47-6.79) for former light smokers to 26.07 (6.58-103.27) for current heavy tobacco smokers at the time of disease occurrence. Combined use of hashish/kiff and snuff had an OR of 6.67 (1.65-26.90), whereas the OR for hashish/kiff (without snuff) was 1.93 (0.57-6.58). History of chronic bronchitis had an OR of 4.16 (1.76-9.85). Other slightly increased risks of lung cancer were found for exposure to passive smoking (1.36; 0.71-2.62), occupational exposures (1.75; 0.84-3.63), use of candles for lighting (1.44; 0.42-5.01), and poor ventilation of the kitchen (1.22; 0.57-2.58). CONCLUSIONS: This study confirms known risk factors for lung cancer and uncovers potential new etiologic ones such as the role of hashish/kiff.

Smoking and its correlates among preadolescent children in France.

BACKGROUND: Smoking often begins in early adolescence, and addiction can occur rapidly. For effective smoking prevention efforts with younger children, knowledge of their early smoking experience is needed. The purpose of this paper was to report the smoking experience of French elementary school children and to describe their lifestyle habits and health knowledge. METHODS: A cross-sectional study of 913 children age 9-11 years in 31 randomly selected schools of the Loire administrative department in France was conducted, using anonymous previously validated questionnaires. Correlates of smoking initiation and intention to smoke in the future were assessed by unconditional logistic regression analysis. RESULTS: A total of 12.3% of the children had smoked at least one cigarette, 5.1% within the previous 30 days. Correlates of ever smoking were male sex, older age, engaging in physical activity, reporting not following safety-related recommendations, or drinking alcohol. Of the 112 children who reported ever smoking, 45.5% stated that they did not want to remain smokers in the future and an additional 26.8% were not sure. CONCLUSIONS: Information on the smoking experience of preadolescents should help in designing effective prevention programs, which are essential for reinforcing abstinence in nonsmokers and preventing others from progressing to addiction.