Odds ratio estimates of the risk of adult myeloid disease according to the smoking status.

<p><b>Abbreviations:</b> No. of datasets, number of datasets; OR, Odds ratio; AOR, Adjusted OR; CI, Confidence interval; Pub. bias, Publication bias.</p><p>Odds ratio estimates of the risk of adult myeloid disease according to the smoking status.</p

Cigarette Smoking and the Risk of Adult Myeloid Disease: A Meta-Analysis

<div><p>Background</p><p>The adult myeloid diseases, myelodysplastic syndrome and acute myeloid leukemia, have been reported to be associated with cigarette smoking, but the results have been conflicting. Previous studies may have ignored the relationship between myelodysplastic syndrome and acute myeloid leukemia, where approximately one-third of myelodysplastic syndrome cases will progress to acute myeloid leukemia, which could induce a serious bias in independent analyses. For the purposes of researching pathogenesis, we suggest that myelodysplastic syndrome and acute myeloid leukemia should be regarded as a single class of adult myeloid disease, and herein assessed the relationship between cigarette smoking and the risk of adult myeloid disease.</p><p>Methods</p><p>The PubMed, Cochrane Library, EBSCO, and EMBASE databases were systematically searched for reports published from 1990 to 2015. Two authors independently assessed the methodological quality and the extracted data. The odds ratios and adjusted odds ratios (OR), a sensitivity analysis, and the publication bias were analyzed using the CMA v2 (Comprehensive Meta Analysis Version 2) software program.</p><p>Results</p><p>Twenty-five studies were included in this meta-analysis. The publication dates ranged from 1990 to 2014. The pooled OR in current smokers and ever-smokers showed an increased risk of adult myeloid disease, with ORs of 1.45 (95% CI, 1.30–1.62; <i>p</i><0.001) and 1.23 (95% CI 1.15–1.32; <i>p</i><0.001) versus non-smokers, respectively. In the subset analyses, the OR of adult myeloid disease was increased regardless of the form of disease, geographical region, NOS (Newcastle Ottawa Scale) score, and source of controls. The smoking status was divided into <20 and ≥20 cigarettes per day, and these groups had ORs of developing adult myeloid disease of 1.24 (95% CI, 1.09–1.40; <i>p</i> = 0.001) and 1.32 (95% CI, 1.14–1.53; <i>p</i><0.001), respectively. In the groups divided based on the number of years the subjects had smoked (<20 and ≥20 years), the ORs were 1.05 (95% CI, 0.90–1.23; <i>p</i> = 0.25) and 1.30 (95% CI, 1.16–1.45; <i>p</i><0.001), respectively. Similarly, <20 and ≥20 pack-years were associated with ORs of 1.15 (95% CI, 1.03–1.29; <i>p</i> = 0.017) and 1.34 (95% CI, 1.18–1.52; <i>p</i><0.001), respectively.</p><p>Conclusions</p><p>This meta-analysis, for the first time, combined myelodysplastic syndrome with acute myeloid leukemia to assess the overall risk of adult myeloid disease, and it demonstrated that cigarette smoking is associated with a significantly increased risk of adult myeloid disease.</p></div

Forest plots of the association of adult myeloid disease with the smoking status based on cigarettes smoked per day (A-B), the duration of smoking (in years) (C-D), and the pack-years smoked (E-F).

<p>Forest plots of the association of adult myeloid disease with the smoking status based on cigarettes smoked per day (A-B), the duration of smoking (in years) (C-D), and the pack-years smoked (E-F).</p

Forest plots of the risk of adult myeloid disease in ever-smokers.

<p>(A) Forms of disease, (B) geographical region, (C) NOS score (high and medium quality), (D) source of controls.</p

The results of subgroup analyses performed according to the potential sources of heterogeneity.

<p><b>Abbreviations:</b> No. of datasets, Number of datasets (papers); MDS, Myelodysplastic Syndrome; AML, Acute Myeloid Leukemia; Nor A, North America; NOS, Newcastle-Ottawa Scale; Pub. bias, Publication bias; CBC, cannot be calculated; OR, odds ratio; AOR, Adjusted OR; CI, Confidence interval; PB, Population-based; HB, Hospital-based.</p><p>The results of subgroup analyses performed according to the potential sources of heterogeneity.</p

Forest plots of the risk of adult myeloid disease in current smokers.

<p>(A) Forms of disease, (B) geographical region, (C) NOS score (high and medium quality), (D) source of controls.</p

Characteristics of the included studies.

<p><b>Abbreviations:</b> No. of subjects, Number of subjects; MDS, Myelodysplastic Syndrome; AML, Acute Myeloid Leukemia; ANNL, Acute Nonlymphocytic Leukemia; NOS, Newcastle-Ottawa Scale; PB, Population-Based; HB, Hospital-Based; BMI, Body Mass Index.</p><p>Characteristics of the included studies.</p

Lag-1 serial correlation coefficients of precipitation on different scales.

<p>Lag-1 serial correlation coefficients of precipitation on different scales.</p

Results of the statistical tests for the seasonal and annual precipitation data over the period from 1957 to 2014.

<p>Results of the statistical tests for the seasonal and annual precipitation data over the period from 1957 to 2014.</p

Lag-1 serial correlation coefficients of temperature on different scales.

<p>Lag-1 serial correlation coefficients of temperature on different scales.</p