发表在《柳叶刀·肿瘤学》上的最新研究表明，胰腺癌或许跟牙周病有关。而补充维生素D则能降低罹患牙周炎的风险。
哈佛大学公共卫生学院和达那癌症研究所的多米尼克·米歇尔教授通过分析和总结22年来收集的数据得到胰腺癌也许与牙周炎有关的结论。从哈佛毕业后，他就加入了“卫生职业者随访研究”（Health Professionals Follow-up Study, HPFS）项目。这是从1986年由哈佛大学公共卫生学院发起的一个活动，他们在美国各地征募到5万多名从事医药卫生工作的男性志愿者参与这项研究。从那个时候起，他们就每两年给志愿者寄去一个健康调查问卷，问卷的内容非常详尽，包括志愿者的生活习惯，饮食搭配，健康状况和疾病情况等等，并且还会通过不定期的抽查体检，来获得更为详细的生理健康数据。“通过这些调查数据，我们就可以发现不同的营养条件和生活习惯对于一系列重要疾病的影响，其中包括死亡率最高的癌症，心脏病和其他心血管疾病。”米歇尔教授在报告的幻灯片里写到。
米歇尔的研究重点在口腔健康和各种癌症的相关性上。2008年，米歇尔和他的同事在著名的医学杂志《柳叶刀》上发表了一篇论文，就20多年来的随访调查的结果进行了分析和总结。结果却让他们有一些意外。在排除诸如吸烟、饮食、年龄等已知的影响因素后，他们发现与牙齿、牙周健康的男性相比，患有牙周病和牙齿缺损的男性得癌症的概率要高14%，其中，肺癌的危险度要高出36%，肾癌的危险度要高49%，血癌是30%，而最高的是胰腺癌，居然高出54%。
这串数字加上它们的前缀不禁让人觉得有些触目惊心。可是这样的关联是怎么产生的呢，米歇尔教授在报告中进一步给我们解释道：“细菌感染牙周并逐渐破坏牙周骨后，就会引发各种牙周疾病。这会导致患者口腔内细菌产生的致癌化合物水平上升，进而还诱发体内组织出现一系列炎症，而反复炎症往往会提高致癌的几率。在这项研究中虽然未能最终确认牙周病直接诱发癌症，但却得出了两者相关的强有力证据。”
而米歇尔的同行，旧金山营养健康研究所的威廉姆·格兰特教授却对此持有不同的看法，他在对米歇尔论文的评论中说：“最近发现牙周炎和牙齿脱落与不同类型的癌症都有相关，认为可能是由于口腔细菌引起的炎症反应造成这样的相关性。但是这些都还只是假设，真正的幕后操纵者有可能是维生素D。我们都知道，缺乏维生素D会使钙被酸化而进一步导致牙齿脱落，口腔发炎。而另一方面，那些表现出和牙周炎高度相关的癌症同样也会被维生素D水平过低引起，因为维生素D和钙水平过低会影响细胞之间介质交换，从而导致癌症的发生。而HPFS的研究也表明，维生素D水平摄入较高的人群得癌症的几率要比其他人群低得多。当然，这也只是另一种可能性，目前我们还需要更多的证据去证明它。”
在中国，胰腺癌的发病率也在逐年上升，近20年增长了4倍。患病者以45岁以上者最为多见，男性高于女性。并且由于其早期症状不明显，临床上尚无简单可靠的早期发现方法，约有85％的胰腺癌患者就诊时已属晚期。所以往往发现之后，患者的平均生存时间仅有4到6个月。显然HPFS的研究为预防胰腺癌带来了一丝曙光，在5万多的调查者中，有216名参与者在22年的随访中被发现患有胰腺癌。研究者最先发现和胰腺癌相关的因素是吸烟和肥胖。除此之外，科学家们发现，与牙齿、牙周健康的男性相比，患有牙周病的男性得胰腺癌的概率要高1.5倍，而适当的补充维生素D可以改善这一状况。（生物谷Bioon.com）
生物谷推荐原始出处：
The Lancet Oncology, Volume 9, Issue 6, Pages 550 - 558, June 2008
Periodontal disease, tooth loss, and cancer risk in male health professionals: a prospective cohort study
Original TextDr Dominique S Michaud ScD a b , Yan Liu MS c, Mara Meyer ScM b, Prof Edward Giovannucci ScD b c d, Prof Kaumudi Joshipura ScD b e f
Background
Studies suggest that tooth loss and periodontal disease might increase the risk of developing various cancers; however, smoking might have confounded the reported associations. We aimed to assess whether periodontal disease or tooth loss is associated with cancer risk.
Methods
The analysis was done in a prospective study (the Health Professionals Follow-Up Study [HPFS]), which was initiated in 1986 when US male health professionals aged 40—75 years responded to questionnaires posted by the Department of Nutrition, Harvard University School of Public Health, Boston, MA, USA. In addition to the baseline questionnaires, follow-up questionnaires were posted to all living participants every 2 years and dietary questionnaires every 4 years. At baseline, participants were asked whether they had a history of periodontal disease with bone loss. Participants also reported number of natural teeth at baseline and any tooth loss during the previous 2 years was reported on the follow-up questionnaires. Smoking status and history of smoking were obtained at baseline and in all subsequent questionnaires. Additionally at baseline, participants reported their mean frequency of food intake over the previous year on a 131-item semiquantitative food-frequency questionnaire. Participants reported any new cancer diagnosis on the follow-up questionnaires. Endpoints for this study were risk of total cancer and individual cancers with more than 100 cases. Multivariate hazard ratios (HRs) and 95% CIs were calculated by use of Cox proportional hazard models according to periodontal disease status and number of teeth at baseline.
Findings
In the main analyses, 48 375 men with median follow-up of 17·7 years (1986 to Jan 31, 2004) were eligible after excluding participants diagnosed with cancer before 1986 (other than non-melanoma skin cancer, n=2076) and those with missing data on periodontal disease (n=1078). 5720 incident cancer cases were documented (excluding non-melanoma skin cancer and non-aggressive prostate cancer). The five most common cancers were colorectal (n=1043), melanoma of the skin (n=698), lung (n=678), bladder (n=543), and advanced prostate (n=541). After adjusting for known risk factors, including detailed smoking history and dietary factors, participants with a history of periodontal disease had an increased risk of total cancer (HR 1·14 [95% CI 1·07—1·22]) compared with those with no history of periodontal disease. By cancer site, significant associations for those with a history of peridontal disease were noted for lung (1·36 [1·15—1·60]), kidney (1·49 [1·12—1·97]), pancreas (1·54 [1·16—2·04]; findings previously published), and haematological cancers (1·30 [1·11—1·53]). Fewer teeth at baseline (0—16) was associated with an increase in risk of lung cancer (1·70 [1·37—2·11]) for those with 0—16 teeth versus those with 25—32 teeth. In never-smokers, periodontal disease was associated with significant increases in total (1·21 [1·06—1·39]) and haematological cancers (1·35 [1·01—1·81]). By contrast, no association was noted for lung cancer (0·96 [0·46—1·98]).
