標(biāo)題 鈣和維生素D補充劑預(yù)防結(jié)直腸腺瘤的效果

背景 流行病學(xué)和基礎(chǔ)研究均提示，增加維生素D和鈣的攝入有助降低結(jié)直腸腺瘤的風(fēng)險。為明確這些化學(xué)藥物預(yù)防方法的實際效果，我們進行了這項隨機、雙盲、安慰劑對照臨床試驗，旨在探究維生素D和鈣對結(jié)直腸腺瘤的作用。

方法 所有入組患者均為新確診的結(jié)直腸腺瘤患者，已接受完整的結(jié)直腸鏡檢查且無結(jié)直腸息肉殘留。最終納入2259名患者，被隨機分為四組：維生素D3組（1000 IU）、碳酸鈣組（1200 mg）、聯(lián)合補充組、安慰劑組。女性受試者在補充碳酸鈣的基礎(chǔ)上可選擇隨機增加維生素D或安慰劑。所有受試者在入組3~5年內(nèi)根據(jù)內(nèi)鏡醫(yī)生的建議，接受內(nèi)鏡隨訪。主要研究終點為試驗期間確診的腺瘤復(fù)發(fā)。

結(jié)果 維生素D3組較安慰劑組受試者體內(nèi)的血清25-羥維生素D平均水平出現(xiàn)7.83 ng/ml的凈增長。總體而言，隨訪期間有43%的受試者出現(xiàn)一個或以上的腺瘤復(fù)發(fā)。維生素D3組、碳酸鈣組、聯(lián)合補充組與安慰劑組比較的校正后腺瘤復(fù)發(fā)危險比分別為0.99、0.95、0.93。嚴(yán)重不良事件罕見。

結(jié)論 本研究提示，腺瘤切除術(shù)后每日補充維生素D3組或碳酸鈣組并未顯著降低術(shù)后3~5年間的腺瘤復(fù)發(fā)風(fēng)險。（本研究由美國國立癌癥研究所資助）

參考文獻(xiàn) Baron, J.A., et al., A Trial of Calcium and Vitamin D for the Prevention of Colorectal Adenomas. New England Journal of Medicine, 2015. 373(16): p. 1519-1530.

A Trial of Calcium and Vitamin D for the Prevention of Colorectal Adenomas

BACKGROUND

Epidemiologic and preclinical data suggest that higher intake and serum levels of vitamin D and higher intake of calcium reduce the risk of colorectal neoplasia. To further study the chemopreventive potential of these nutrients, we conducted a randomized, double-blind, placebo-controlled trial of supplementation with vitamin D, calcium, or both for the prevention of colorectal adenomas.

METHODS

We recruited patients with recently diagnosed adenomas and no known colorectal polyps remaining after complete colonoscopy. We randomly assigned 2259 participants to receive daily vitamin D3 (1000 IU), calcium as carbonate (1200 mg), both, or neither in a partial 2×2 factorial design. Women could elect to receive calcium plus random assignment to vitamin D or placebo. Follow-up colonoscopy was anticipated to be performed 3 or 5 years after the baseline examinations, according to the endoscopist’s recommendation. The primary end point was adenomas diagnosed in the interval from randomization through the anticipated surveillance colonoscopy.

RESULTS

Participants who were randomly assigned to receive vitamin D had a mean net increase in serum 25-hydroxyvitamin D levels of 7.83 ng per milliliter, relative to participants given placebo. Overall, 43% of participants had one or more adenomas diagnosed during follow-up. The adjusted risk ratios for recurrent adenomas were 0.99 (95% confidence interval [CI], 0.89 to 1.09) with vitamin D versus no vitamin D, 0.95 (95% CI, 0.85 to 1.06) with calcium versus no calcium, and 0.93 (95% CI, 0.80 to 1.08) with both agents versus neither agent. The findings for advanced adenomas were similar. There were few serious adverse events.

CONCLUSIONS

Daily supplementation with vitamin D3 (1000 IU), calcium (1200 mg), or both after removal of colorectal adenomas did not significantly reduce the risk of recurrent colorectal adenomas over a period of 3 to 5 years. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT00153816.)