Consumption of Sugar-Sweetened Soft Drinks and Risk of Gastrointestinal Cancer: A Systematic Review and Meta-Analysis of Observational Studies.

INTRODUCTION: Previous observational studies have reported inconsistent findings on the association between consumption of sugar-sweetened soft drinks (SSSDs) and the risk of gastrointestinal (GI) cancer. This study investigated the associations between SSSD consumption and the risk of GI cancer using a systematic review and meta-analysis. METHODS: Observational epidemiological studies were searched from the PubMed and EMBASE databases until June 2021. We conducted a meta-analysis of all included studies and subgroup meta-analyses based on various factors. RESULTS: In a meta-analysis of 27 studies with nine case-control studies and 18 cohort studies, the consumption of SSSDs was modestly associated with an increased risk of GI cancer (odds ratio [OR]/relative risk [RR]: 1.08; 95% confidence interval [CI]: 1.01-1.16), with a significant positive dose-response relationship. In the subgroup meta-analysis by study design, there was a significant positive association between the consumption of SSSDs and GI cancer in cohort studies (RR: 1.11; 95% CI: 1.03-1.20; n = 18), but not in case-control studies. In the subgroup meta-analysis by type of cancer, consumption of SSSDs was significantly associated with an increased risk of colorectal cancer (OR/RR: 1.13; 95% CI: 1.07-1.19). CONCLUSIONS: This meta-analysis suggests that SSSD consumption significantly increases the risk of GI cancer, specifically colorectal cancer.

Association between seafood intake and the risk of thyroid cancer.

Background: Previous observational epidemiological studies such as case-control studies and cohort studies have reported inconsistent results regarding the associations between seafood intake and the risk of thyroid cancer. Materials and methods: We searched PubMed and EMBASE in August 2021 using keywords related to seafood intake and thyroid cancer. A pooled odds ratio (OR) or relative risk (RR) with its 95% confidence interval (CI) was calculated. Results: We included 17 observational studies with 13 case-control studies and 4 cohort studies, which included 4,309 thyroid cancer patients among 599,161 participants. In the random effects model meta-analysis of all 17 studies, we found that there was no significant association between seafood intake (highest vs. lowest intake) and the risk of thyroid cancer (OR or RR, 1.01; 95% CI: 0.86 to 1.19; I2=51.4%). Although the associations were not statistically significant, subgroup meta-analyses by study design showed opposite findings: seafood intake decreased the risk of thyroid cancer in case-control studies (OR or RR, 0.94; 95% CI: 0.74 to 1.19; I2=60.6%; n=13) but increased in cohort studies (OR or RR, 1.14; 95% CI: 0.97 to 1.35; I2=0.0%; n=4). Conclusion: The current meta-analysis of observational epidemiological studies found that that overall, there was no significant association between seafood intake and the risk of thyroid cancer. However, given that cohort studies give us a higher level of evidence than case-control studies, further prospective cohort studies are warranted to confirm the association between them.

Proton pump inhibitors and risk of gastrointestinal cancer: A meta­analysis of cohort studies.

Although proton pump inhibitors (PPIs) are widely used in the treatment of various acid-related disorders, observational studies have raised concern about an association between PPI use and the risk of gastrointestinal cancer. The present study aimed to investigate the association between them using a meta-analysis of cohort studies. PubMed and Excerpta Medica dataBASE were searched from inception to December 2022 to identify relevant cohort studies. The primary outcome was the risk of gastrointestinal cancer among PPI users, expressed as a pooled odds ratio (OR), relative risk (RR) or hazard ratio (HR) and its 95% CI based on a random-effects model. A total of 25 cohort studies from 23 articles were included in the final analysis. In the meta-analysis of all studies, an increased risk of gastrointestinal cancer following the use of PPIs was observed (OR/RR/HR, 2.09; 95% CI, 1.78-2.46). Subgroup analyses by type of cancer also revealed an association between PPI use and the risk of esophageal, gastric, liver and pancreatic cancer, whereas there was no association for colorectal cancer. The increased risk of gastrointestinal cancer was also observed in individuals who had used PPIs for <1 year (OR/RR/HR, 5.23; 95% CI, 2.96-9.24) as well as individuals who had used PPIs for up to 3 years. The present meta-analysis revealed that the use of PPIs was associated with an increased risk of gastrointestinal cancer.

Exploring Connections between Oral Microbiota, Short-Chain Fatty Acids, and Specific Cancer Types: A Study of Oral Cancer, Head and Neck Cancer, Pancreatic Cancer, and Gastric Cancer.

The association between oral microbiota and cancer development has been a topic of intense research in recent years, with compelling evidence suggesting that the oral microbiome may play a significant role in cancer initiation and progression. However, the causal connections between the two remain a subject of debate, and the underlying mechanisms are not fully understood. In this case-control study, we aimed to identify common oral microbiota associated with several cancer types and investigate the potential mechanisms that may trigger immune responses and initiate cancer upon cytokine secretion. Saliva and blood samples were collected from 309 adult cancer patients and 745 healthy controls to analyze the oral microbiome and the mechanisms involved in cancer initiation. Machine learning techniques revealed that six bacterial genera were associated with cancer. The abundance of Leuconostoc, Streptococcus, Abiotrophia, and Prevotella was reduced in the cancer group, while abundance of Haemophilus and Neisseria enhanced. G protein-coupled receptor kinase, H+-transporting ATPase, and futalosine hydrolase were found significantly enriched in the cancer group. Total short-chain fatty acid (SCFAs) concentrations and free fatty acid receptor 2 (FFAR2) expression levels were greater in the control group when compared with the cancer group, while serum tumor necrosis factor alpha induced protein 8 (TNFAIP8), interleukin-6 (IL6), and signal transducer and activator of transcription 3 (STAT3) levels were higher in the cancer group when compared with the control group. These results suggested that the alterations in the composition of oral microbiota can contribute to a reduction in SCFAs and FFAR2 expression that may initiate an inflammatory response through the upregulation of TNFAIP8 and the IL-6/STAT3 pathway, which could ultimately increase the risk of cancer onset.

Exposure to Electronic Cigarette Advertisements and Use of Electronic Cigarettes: A Meta-analysis of Prospective Studies.

INTRODUCTION: Electronic cigarette (EC) advertisements remain unregulated and approach consumers in TV commercials, print ads, radio, and other forms of digital marketing. AIMS AND METHODS: This study aimed to assess whether exposure to EC advertisements is associated with the use of EC by using a meta-analysis of prospective studies. We searched PubMed, EMBASE, and Web of Science to locate eligible studies in November 2021. Pooled adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were calculated using a random-effects meta-analysis. RESULTS: Out of 1635 articles searched from databases, we included seven prospective studies that met inclusion criteria in the final analysis. Four out of seven studies involved participants under 18 years of age. In the meta-analysis of all studies, exposure to EC advertisements was significantly associated with the increased use of ECs (aOR = 1.53, 95% CI 1.22 to 1.92; I2 = 60.1%). In the subgroup meta-analyses by source of advertisements, there was no significant association between exposure to EC advertisements on TV, radio, or billboards and the use of EC, while exposure to EC advertisements in retail stores and on Internet or social media significantly increased the use of EC. CONCLUSIONS: Exposure to EC advertisements was associated with the increased use of ECs, specifically in retail stores and on Internet or social media among adolescents and young adults. Because EC use could serve as a gateway to cigarette smoking in adolescents and young adults, more strict regulations and restrictions on EC advertisements are needed. IMPLICATIONS: Concurrent with the rise in electronic cigarette (EC) sales, advertising expenditures for ECs have been increased in the past decade, and there is controversy over the association between exposure to EC advertisements and the use of ECs. This meta-analysis of seven prospective studies showed that exposure to EC advertisements was significantly associated with the increased use of ECs, specifically in retail stores and on Internet or social media among adolescents and young adults. Because, EC use could serve as a gateway to cigarette smoking in adolescents and young adults, more strict regulations and restrictions on EC advertisements are needed.

Coffee Intake and Risk of Hypertension: A Meta-Analysis of Cohort Studies.

BACKGROUND: It remains unclear whether coffee intake is associated with the risk of hypertension. This study aimed to investigate the association between coffee intake and the risk of hypertension by using a meta-analysis of cohort studies. METHODS: PubMed and Embase were searched using keywords in September 2022 to identify studies on coffee intake and the risk of hypertension. RESULTS: We included a total of 13 longitudinal cohort studies, which involved a total of 64,650 incident cases of hypertension among 314,827 participants. In a random effects model meta-analysis of all the studies, coffee intake was not significantly associated with the risk of hypertension (relative risk [RR], 0.97; 95% confidence interval [CI], 0.90­1.05; I² = 58.0%; n = 13). In the subgroup meta-analysis, coffee intake was associated with a decreased risk of hypertension in studies conducted in America (RR, 0.93; 95% CI, 0.87-0.98; I² = 4.6%; n = 5) and in low-quality studies (RR, 0.92; 95% CI, 0.88-0.96; I² = 0.0%; n = 7). In the remaining subgroup meta-analyses by amount of coffee intake, gender, type of coffee (decaffeinated vs. caffeinated), smoking, and years of follow-up, coffee intake was not significantly associated with the risk of hypertension. CONCLUSION: The current meta-analysis showed that coffee intake is not associated with the risk of hypertension.

Oral contraceptives and risk of breast cancer and ovarian cancer in women with a BRCA1 or BRCA2 mutation: a meta-analysis of observational studies.

It remains inconclusive whether the use of oral contraceptives (OCs) alters the risks of breast or ovarian cancer in women with a breast cancer susceptibility gene 1 (BRCA1) or breast cancer susceptibility gene 2 (BRCA2) mutation. We investigated the association between OC use and the risks of breast or ovarian cancer in this group by using a meta-analysis. PubMed and EMBASE were searched using keywords until February 2021 to identify relevant studies that evaluated the association between OC ever use and the risks of breast or ovarian cancer in women with a BRCA1 or BRCA2 mutation. Twelve studies for breast cancer and eight studies for ovarian cancer were identified. In the random-effects meta-analysis, the ever use of OCs was significantly associated with an increased risk of breast cancer [odds ratio (OR), relative risk (RR) or hazard ratio (HR) = 1.24; 95% confidence interval (CI) 1.08-1.41] and a decreased risk of ovarian cancer (OR/RR/HR = 0.53, 95% CI 0.41-0.67). Consistent findings were observed when BRCA1 and BRCA2 mutation carriers were analyzed separately. The increased risk of breast cancer was observed only in the long-term (>5 years) users of OCs, while the decreased risk of ovarian cancer was observed regardless of the duration of OC use. The current study suggests that the ever use of OCs in BRCA mutation carriers is significantly associated with an increased risk of breast cancer and a decreased risk of ovarian cancer. Therefore, the use of OCs as chemoprevention of ovarian cancer should be cautious in BRCA mutation carriers.

Night shift work and breast cancer risk: a meta-analysis of observational epidemiological studies.

Previous observational epidemiological studies have reported inconsistently the association between night shift work (NSW) and the risk of breast cancer (BC). This study aimed to investigate those associations by using a meta-analysis of observational epidemiological studies. We searched PubMed and EMBASE using keywords related to this topic from inception till November 2020. The pooled effect sizes such as odds ratio (OR), hazard ratio (HR) or relative risk (RR) with 95% confidence interval (CI) were calculated using a random-effects model. In the meta-analysis of a total of 32 observational studies including 13 case-control studies, 4 nested case-control studies and 15 cohort studies, NSW significantly increased the risk of BC (OR/RR/HR, 1.11; 95% CI, 1.04-1.20; I2 = 72.4%). In the subgroup meta-analysis by type of study, NSW was also associated with the increased risk of BC in case-control studies (OR, 1.34; 95% CI, 1.17-1.53; I2 = 63.8%). However, no significant association was found in both nested case-control studies (OR, 1.14; 95% CI, 0.89-1.46; I2 = 65.8%) and cohort studies (RR/HR, 0.98; 95% CI, 0.93-1.03; I2 = 25.3%). Besides, there was no significant association between NSW for over 20 years and the risk of BC (OR/RR/HR, 1.03; 95% CI, 0.95-1.11; I2 = 36.6%, n = 14). Given that cohort studies provide higher evidence than case-control studies, there is no association between NSW and the risk of BC.

A Health Information Quality Assessment Tool for Korean Online Newspaper Articles: Development Study.

BACKGROUND: Concern regarding the reliability and accuracy of the health-related information provided by online newspaper articles has increased. Numerous criteria and items have been proposed and published regarding the quality assessment of online information, but there is no standard quality assessment tool available for online newspapers. OBJECTIVE: This study aimed to develop the Health Information Quality Assessment Tool (HIQUAL) for online newspaper articles. METHODS: We reviewed previous health information quality assessment tools and related studies and accordingly developed and customized new criteria. The interrater agreement for the new assessment tool was assessed for 3 newspaper articles on different subjects (colorectal cancer, obesity genetic testing, and hypertension diagnostic criteria) using the Fleiss κ and Gwet agreement coefficient. To compare the quality scores generated by each pair of tools, convergent validity was measured using the Kendall τ ranked correlation. RESULTS: Overall, the HIQUAL for newspaper articles comprised 10 items across 5 domains: reliability, usefulness, understandability, sufficiency, and transparency. The interrater agreement for the article on colorectal cancer was in the moderate to substantial range (Fleiss κ=0.48, SE 0.11; Gwet agreement coefficient=0.74, SE 0.13), while for the article introducing obesity genetic testing it was in the substantial range, with values of 0.63 (SE 0.28) and 0.86 (SE 0.10) for the two measures, respectively. There was relatively low agreement for the article on hypertension diagnostic criteria at 0.20 (SE 0.10) and 0.75 (SE 0.13), respectively. Validity of the correlation assessed with the Kendall τ showed good correlation between tools (HIQUAL vs DISCERN=0.72, HIQUAL vs QUEST [Quality Evaluation Scoring Tool]=0.69). CONCLUSIONS: We developed a new assessment tool to evaluate the quality of health information in online newspaper articles, to help consumers discern accurate sources of health information. The HIQUAL can help increase the accuracy and quality of online health information in Korea.

Reply to Brzozek et al. Comment on "Choi et al. Cellular Phone Use and Risk of Tumors: Systematic Review and Meta-Analysis. Int. J. Environ. Res. Public Health 2020, 17, 8079".

We appreciate Christopher Brzozek and his colleagues' interest [...].

Reply to Comment on Choi, Y.-J., et al. Cellular Phone Use and Risk of Tumors: Systematic Review and Meta-Analysis. Int. J. Environ. Res. Public Health 2020, 17, 8079.

We appreciate Frank de Vocht and Martin Röösli's interest [...].

Gynecological cancer and omega-3 fatty acid intakes: Meta-analysis.

BACKGROUND AND OBJECTIVES: Previous observational epidemiological studies have reported inconsistent findings on the association between dietary intake of omega-3 fatty acids and endocrine-related gynecological cancer including ovarian cancer and endometrial cancer. This study aimed to investigate this association using a metaanalysis of observational studies. METHODS AND STUDY DESIGN: We searched PubMed, EMBASE, and Cochrane library by using keywords related to the topic in December 2019. The pooled odd ratios (pORs), pooled relative risks (pRRs), or pooled hazard ratios (pHRs) with 95% confidence intervals (CIs) were calculated based on a random- effects model. Also, we performed subgroup analyses by methodological quality, type of cancer, study design, and type of omega-3 fatty acids. RESULTS: A total of 10 observational studies with six case-control and four prospective cohort studies were included in the current meta-analysis. In the meta-analysis of all studies, dietary intake of omega-3 fatty acids was not significantly associated with the risk of endometrial and ovarian cancers (pOR/HR, 0.87; 95% CI, 0.73-1.04; I2=67.2%) (highest versus lowest intake). In the subgroup analysis by type of study, no significant association was found in cohort studies (pHR, 1.03; 95% CI, 0.63-1.67, I2=81.9%), whereas dietary intake of omega-3 fatty acids was associated with the decreased risk of endocrine-related gynecological cancers in case-control studies (pOR, 0.81; 95% CI, 0.67 to 0.98, I2=55.7%). CONCLUSIONS: The current metaanalysis of observational studies suggests that dietary intake of omega-3 fatty acids is not significantly associated with the risk of endocrine-related gynecological cancer.

The Impact of COVID-19 on Cancer Care in the Post Pandemic World: Five Major Lessons Learnt from Challenges and Countermeasures of Major Asian Cancer Centres.

OBJECTIVE: The COVID-19 pandemic has dramatically affected healthcare services around Asia. The Asian National Cancer Centres Alliance and the Asia-Pacific Organisation for Cancer Prevention collaborated to assess the mid- and long- term impact of COVID-19 to cancer care in Asia. METHODS: The two entities organised a combined symposium and post-meeting interactions among representatives of major cancer centres from seventeen Asian countries to outlining major challenges and countermeasures. RESULTS: Participating stakeholders distilled five big questions. 1) "Will there be an explosion of late-stage cancers after the pandemic?" To address and recover from perceived delayed prevention, screening, treatment and care challenges, collaboration of key stakeholders in the region and alignment in cancer care management, policy intervention and cancer registry initiatives would be of essential value. 2) "Operations and Finance" The pandemic has resulted in significant material and financial casualties. Flagged acute challenges (shortages of supplies, imposition of lockdown) as well as longer-standing reduction of financial revenue, manpower, international collaboration, and training should also be addressed. 3) "Will telemedicine and technological innovations revolutionize cancer care?" Deploying and implementing telemedicine such as teleconsultation and virtual tumour boards were considered invaluable. These innovations could become a new regular practice, leading to expansion of tele-collaboration through collaboration of institutions in the region. 4) "Will virtual conferences continue after the pandemic?" Virtual conferences during the pandemic have opened new doors for knowledge sharing, especially for representatives of low- and middle-income countries in the region, while saving time and costs of travel. 5) "How do we prepare for the next pandemic or international emergency?" Roadmaps for action to improve access to appropriate patient care and research were identified and scrutinised. CONCLUSION: Through addressing these five big questions, focused collaboration among members and with international organisations such as City Cancer Challenge will allow enhanced preparedness for future international emergencies.
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Consumption of artificially sweetened soft drinks and risk of gastrointestinal cancer: a meta-analysis of observational studies.

OBJECTIVE: There remain inconclusive findings from previous observational epidemiological studies on whether consumption of artificially sweetened soft drinks (ASSD) increases the risk of gastrointestinal (GI) cancer. We investigated the associations between the consumption of ASSD and the risk of GI cancer using a meta-analysis. DESIGN: Systematic review and meta-analysis. SETTING: PubMed and EMBASE were searched using keywords until May 2020 to identify observational epidemiological studies on the association between the consumption of ASSD and the risk of GI cancer. SUBJECTS: Twenty-one case-control studies and seventeen cohort studies with 12 397 cancer cases and 2 474 452 controls. RESULTS: In the random-effects meta-analysis of all the studies, consumption of ASSD was not significantly associated with the risk of overall GI cancer (OR/relative risk (RR), 1·02; 95 % CI, 0·92, 1·14). There was no significant association between the consumption of ASSD and the risk of overall GI cancer in the subgroup meta-analyses by study design (case-control studies: OR, 0·95; 95 % CI, 0·82, 1·11; cohort studies: RR, 1·14; 95 % CI, 0·97, 1·33). In the subgroup meta-analysis by type of cancer, consumption of ASSD was significantly associated with the increased risk of liver cancer (OR/RR, 1·28; 95 % CI, 1·03, 1·58). CONCLUSIONS: The current meta-analysis of observational epidemiological studies suggests that overall, there is no significant association between the consumption of ASSD and the risk of GI cancer.

Cellular Phone Use and Risk of Tumors: Systematic Review and Meta-Analysis.

We investigated whether cellular phone use was associated with increased risk of tumors using a meta-analysis of case-control studies. PubMed and EMBASE were searched from inception to July 2018. The primary outcome was the risk of tumors by cellular phone use, which was measured by pooling each odds ratio (OR) and its 95% confidence interval (CI). In a meta-analysis of 46 case-control studies, compared with never or rarely having used a cellular phone, regular use was not associated with tumor risk in the random-effects meta-analysis. However, in the subgroup meta-analysis by research group, there was a statistically significant positive association (harmful effect) in the Hardell et al. studies (OR, 1.15-95% CI, 1.00 to 1.33- n = 10), a statistically significant negative association (beneficial effect) in the INTERPHONE-related studies (case-control studies from 13 countries coordinated by the International Agency for Research on Cancer (IARC); (OR, 0.81-95% CI, 0.75 to 0.89-n = 9), and no statistically significant association in other research groups' studies. Further, cellular phone use with cumulative call time more than 1000 h statistically significantly increased the risk of tumors. This comprehensive meta-analysis of case-control studies found evidence that linked cellular phone use to increased tumor risk.

Comparative Efficacy of Targeted Therapies in Patients with Non-Small Cell Lung Cancer: A Network Meta-Analysis of Clinical Trials.

This study aims to investigate the efficacy of targeted therapies in the treatment of non-small cell lung cancer (NSCLC) by using a network meta-analysis of clinical trials. PubMed, EMBASE, Cochrane Library, and Clinicaltrials.gov were searched by using keywords related to the topic on 19 September 2018. Two investigators independently selected relevant trials by pre-determined criteria. A pooled response ratio (RR) for overall response rate (ORR) and a hazard ratio (HR) for progression-free survival (PFS) were calculated based on both the Bayesian and frequentist approaches. A total of 128 clinical trials with 39,501 participants were included in the final analysis of 14 therapeutic groups. Compared with chemotherapy, both ORR and PFS were significantly improved for afatinib, alectinib, and crizotinib, while only PFS was significantly improved for cabozantinib, ceritinib, gefitinib, and osimertinib. Consistency was observed between the direct and indirect comparisons based on the Bayesian approach statistically and the frequentist approach visually. Cabozantinib and alectinib showed the highest probability for the first-line treatment ranking in ORR (62.5%) and PFS (87.5%), respectively. The current network meta-analysis showed the comprehensive evidence-based comparative efficacy of different types of targeted therapies, which would help clinicians use targeted therapies in clinical practice.

Efficacy of Crizotinib, Ceritinib, and Alectinib in ALK-Positive Non-Small Cell Lung Cancer Treatment: A Meta-Analysis of Clinical Trials.

This study aimed to evaluate the efficacy of anaplastic lymphoma kinase (ALK)-inhibitors in the treatment of ALK-positive non-small cell lung cancer (NSCLC) by using a meta-analysis of clinical trials. We searched PubMed, EMBASE, Cochrane Library, and Clinicaltrials.gov by using keywords related to the topic in August 2018. The pooled effect sizes were calculated based on a random-effects model. We also performed subgroup meta-analysis by types of ALK inhibitors (crizotinib, ceritinib, and alectinib). A total of 20 clinical trials with 10 single-arm trials and 10 double-arm trials were included in the final meta-analysis. The median overall survival (OS), progression-free survival (PFS), overall response rate (ORR), disease control rate (DCR), 1 year survival rate, and 2 year survival rate were 19.14 months, 8.47 months, 62%, 78%, 74%, and 62%, respectively. ALK inhibitors showed a significantly superior efficacy compared with chemotherapy (hazard ratio (HR) for OS, 0.83; HR for PFS, 0.43; rate difference (RD) for ORR, 0.23; and RD for DCR, 0.10). The current meta-analysis of clinical trials showed the significant efficacy of ALK inhibitors in the treatment of ALK-positive NSCLC. Further head-to-head trials are needed to compare their efficacy with other types of NSCLC treatment regimens. PROSPERO registration: CRD42018085987.

Dietary Intake of Omega-3 fatty acids and Endocrine-related Gynecological Cancer: A Meta-Analysis of Observational Studies.

PURPOSE: Previous observational epidemiological studies have reported inconsistent findings on the association between dietary intake of omega-3 fatty acids and endocrine-related gynecological cancer such as ovarian cancer and endometrial cancer. This study aimed to investigate this association using a meta-analysis of observational studies. MATERIALS AND METHODS: We searched PubMed, EMBASE, and Cochrane library by using key words related with the topic in April 2017. The pooled odd ratios (pORs), relative risks (pRRs), or hazard ratios (pHRs) with 95% confidence intervals (CIs) were calculated based on the random-effects model. Also, we performed subgroup meta-analysis by methodological quality, types of cancer, study design, and omega-3 fatty acids. RESULTS: A total of ten observational studies with six case-control and four cohort studies were included in the final meta-analysis. In the meta-analysis of all the studies, dietary intake of total omega-3 fatty acids was not significantly associated with the risk of endometrial and ovarian cancers (pOR/HR, 0.87; 95% CI, 0.73-1.04; I2=67.2%) (highest versus lowest intake). In the subgroup meta-analysis by type of study, there was no significant association between them in cohort studies (pHR, 1.03; 95% CI, 0.63-1.67, I2=81.9%), whereas its reduced risk was observed in case-control studies (pOR, 0.81; 95% CI, 0.67 to 0.98, I2=55.7%). CONCLUSION: The current meta-analysis of observational studies suggests that there is no higher level of evidence to support the protective effect of dietary omega-3 fatty acids on endocrine-related gynecological cancer. Further prospective studies should be conducted to confirm the association.

Efficacy of Pharmacotherapy for Smoking Cessation in Adolescent Smokers: A Meta-analysis of Randomized Controlled Trials.

INTRODUCTION: This study aimed to evaluate the efficacy of pharmacotherapy for smoking cessation among adolescent smokers by using a meta-analysis of randomized controlled trials (RCTs). METHODS: PubMed, EMBASE, and Cochrane Library were searched from the inception to January 20, 2018. We included RCTs of pharmacotherapy for smoking cessation among adolescent smokers aged less than 20 years. Data were pooled using a random-effects meta-analysis. The primary outcome measures were a smoking abstinence rate and its relative risk (RR) at the longest follow-up period in each study validated by biochemical markers. RESULTS: Among a total of 1035 articles searched, nine RCTs, which involved 1188 adolescent smokers aged 12-20 years with 627 in the intervention group and 561 in the control group, were included in the final analysis. In the random-effects meta-analysis of all the nine trials, pharmacotherapy showed a increased abstinence rate (RR = 1.62; 95% confidence interval [CI] = 1.08 to 2.44, I2 = 0.0%), compared with the control group. Subgroup meta-analyses by follow-up period showed an increased abstinence rate at 4 weeks (RR = 1.87; 95% CI = 1.22 to 2.87; n = 4) and a nonsignificantly increased abstinence rate during the longer term follow-up periods at 8, 12, 24, and 52 weeks. CONCLUSIONS: The current meta-analysis suggests that pharmacotherapy can be considered as an aid for smoking cessation in the short-term period among adolescent smokers. However, further large RCTs are warranted to determine its long-term efficacy and safety. IMPLICATIONS: In this meta-analysis of nine RCTs with 1188 adolescent smokers aged 12-20 years, pharmacotherapy showed an increased abstinence rate, compared with the control group. In the subgroup meta-analyses by follow-up period, it showed the increased abstinence rate at 4 weeks and no efficacy on abstinence during the longer term follow-up periods up to 52 weeks. Further large RCTs are warranted to determine the long-term efficacy and safety of pharmacotherapy in adolescent smokers.

Type 1 diabetes mellitus and risk of cancer: a meta-analysis of observational studies.

OBJECTIVE: Previous observational studies have focused on the link between type 2 diabetes and the risk of cancer. However, the association between type 1 diabetes and the risk of cancer has not been well addressed. This study aimed to investigate the association between type 1 diabetes and the risk of cancer by using a meta-analysis of observational studies. METHODS: We searched PubMed and EMBASE for observational studies that examined the association between type 1 diabetes and cancer in April 2017. We calculated the pooled odds ratios (ORs) or relative risks (RRs) with confidence intervals (CIs) from individual studies based on a random-effects model meta-analysis. RESULTS: We included a total of 15 observational studies with two case-control studies and 13 cohort studies involving 31 893 cancer patients among a total of 1 915 179 participants in the final analysis. In the random-effects meta-analysis of all studies, patients with type 1 diabetes had an increased risk of cancer (OR or RR, 1.29; 95% CI, 1.09-1.52; n = 15; I2 = 95.2%). In the subgroup meta-analysis by type of cancer, type 1 diabetes significantly increased the risk of cancers of stomach, lung, pancreas, liver, ovary and kidney, whereas it significantly decreased the risk of breast cancer (OR or RR, 0.91; 95% CI, 0.86-0.95; n = 9; I2 = 0%). CONCLUSION: This meta-analysis suggests that type 1 diabetes is associated with the increased risk of several types of cancer and the decreased risk of breast cancer. However, the plausible mechanisms for the decreased risk of breast cancer remain unclear. Further prospective studies with proper adjustment for possible confounding factors are warranted.