Dataset Information

Effects of calcium on the incidence of recurrent colorectal adenomas: A systematic review with meta-analysis and trial sequential analysis of randomized controlled trials.

ABSTRACT:

Background

Protective effects of calcium supplementation against colorectal adenomas have been documented in systematic reviews; however, the results have not been conclusive. Our objective was to update and systematically evaluate the evidence for calcium supplementation taking into consideration the risks of systematic and random error and to GRADE the evidence.

Methods

The study comprised a systematic review with meta-analysis and trial sequential analysis (TSA) of randomized controlled trials (RCTs). We searched for RCTs published up until September 2016. Retrieved trials were evaluated using risk of bias. Primary outcome measures were the incidences of any recurrent adenomas and of advanced adenomas. Meta-analytic estimates were calculated with the random-effects model and random errors were evaluated with trial sequential analyses (TSAs).

Results

Five randomized trials (2234 patients with a history of adenomas) were included. Two of the 5 trials showed either unclear or high risks of bias in most criteria. Meta-analysis of good quality RCTs suggest a moderate protective effect of calcium supplementation on recurrence of adenomas (relative risk [RR], 0.88 [95% CI 0.79-0.99]); however, its effects on advanced adenomas did not show statistical significance (RR, 1.02 [95% CI 0.67-1.55]). Subgroup analyses demonstrated a greater protective effect on recurrence of adenomas with elemental calcium dose ?1600?mg/day (RR, 0.74 [95% CI 0.56-0.97]) compared to ?1200?mg/day (RR, 0.84 [95% CI 0.73-0.97]). No major serious adverse events were associated with the use of calcium, but there was an increase in the incidence of hypercalcemia (P?=?.0095). TSA indicated a lack of firm evidence for a beneficial effect. Concerns with directness and imprecision rated down the quality of the evidence to "low."

Conclusion

The available good quality RCTs suggests a possible beneficial effect of calcium supplementation on the recurrence of adenomas; however, TSA indicated that the accumulated evidence is still inconclusive. Using GRADE-methodology, we conclude that the quality of evidence is low. Large well-designed randomized trials with low risk of bias are needed.

SUBMITTER: Veettil SK

PROVIDER: S-EPMC5556213 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Publications

Effects of calcium on the incidence of recurrent colorectal adenomas: A systematic review with meta-analysis and trial sequential analysis of randomized controlled trials.

Veettil Sajesh K SK Ching Siew Mooi SM Lim Kean Ghee KG Saokaew Surasak S Phisalprapa Pochamana P Chaiyakunapruk Nathorn N

Medicine 20170801 32

<h4>Background</h4>Protective effects of calcium supplementation against colorectal adenomas have been documented in systematic reviews; however, the results have not been conclusive. Our objective was to update and systematically evaluate the evidence for calcium supplementation taking into consideration the risks of systematic and random error and to GRADE the evidence.<h4>Methods</h4>The study comprised a systematic review with meta-analysis and trial sequential analysis (TSA) of randomized c ...[more]

PMID: 28796047

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Project description:To determine the efficacy of calcium supplementation in reducing the recurrence of colorectal adenomas.We conducted a systematic review and meta-analysis of published studies. We searched PubMed, Scopus, the Cochrane Library, the WHO International Clinical Trials Registry Platform, and the ClinicalTrials.gov website, through December 2015. Randomized, placebo-controlled trials assessing supplemental calcium intake for the prevention of recurrence of adenomas were eligible for inclusion. Two reviewers independently selected studies based on predefined criteria, extracted data and outcomes (recurrence of colorectal adenomas, and advanced or "high-risk" adenomas), and rated each trial's risk-of-bias. Between-study heterogeneity was assessed, and pooled risk ratio (RR) estimates with their 95% confidence intervals (95%CI) were calculated using fixed- and random-effects models. To express the treatment effect in clinical terms, we calculated the number needed to treat (NNT) to prevent one adenoma recurrence. We also assessed the quality of evidence using GRADE.Four randomized, placebo-controlled trials met the eligibility criteria and were included. Daily doses of elemental calcium ranged from 1200 to 2000 mg, while the duration of treatment and follow-up of participants ranged from 36 to 60 mo. Synthesis of intention-to-treat data, for participants who had undergone follow-up colonoscopies, indicated a modest protective effect of calcium in prevention of adenomas (fixed-effects, RR = 0.89, 95%CI: 0.82-0.96; random-effects, RR = 0.87, 95%CI: 0.77-0.98; high quality of evidence). The NNT was 20 (95%CI: 12-61) to prevent one colorectal adenoma recurrence within a period of 3 to 5 years. On the other hand, the association between calcium treatment and advanced adenomas did not reach statistical significance (fixed-effects, RR = 0.92, 95%CI: 0.75-1.13; random-effects, RR = 0.92, 95%CI: 0.71-1.18; moderate quality of evidence).Our results suggest a modest chemopreventive effect of calcium supplements against recurrent colorectal adenomas over a period of 36 to 60 mo. Further research is warranted.

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Project description:Background Primary osteoporosis (PO) is a systemic metabolic skeletal disease. Previous studies have shown that moxibustion can reduce pain intensity and enhance response rate, bone mineral density (BMD), and living function of the patients with PO. However, consensus on its efficacy does not exist, and evidence of moxibustion for PO is also insufficient. Methods We searched five English and four Chinese databases with various additional sources and published reviews through December 1, 2021, to evaluate potentially concerned randomized controlled trials (RCTs). Two independent researchers addressed selection screening, data extraction, and risk of bias assessment. The data of this meta-analysis were analyzed using the RevMan v.5.4 software. Additionally, the trial sequential analysis v.0.9.5.10 β was used to estimate the sample size. In contrast, the quality of evidence from the RCTs was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation tool. Results The current meta-analysis included 14 RCTs containing 898 participants. The methodological quality of the RCTs was moderate. The review demonstrated that a combination of moxibustion and conventional medicine (CM) significantly reduced pain intensity and improved the BMD compared with CM. Furthermore, it was found that moxibustion plus CM/moxibustion could improve response rates compared with CM. However, it was found that the reduction of pain intensity and improvement of BMD by moxibustion showed no significant difference compared with CM. It was also evident that the sample size of most outcomes was inadequate. Moreover, all evidence obtained in this study was ranked as low to critically low. Conclusions In conclusion, it was demonstrated that moxibustion is a potentially effective agent for treating PO. However, high-quality studies should be implemented in the future because this study only obtained low-quality evidence. This study was registered in the PROSPERO platform (CRD42021291310).

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Dataset Information

Effects of calcium on the incidence of recurrent colorectal adenomas: A systematic review with meta-analysis and trial sequential analysis of randomized controlled trials.

Background

Methods

Results

Conclusion

Publications

Effects of calcium on the incidence of recurrent colorectal adenomas: A systematic review with meta-analysis and trial sequential analysis of randomized controlled trials.

Similar Datasets

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