《柳叶刀》主编又怒了：医学与营养——不可理喻！
2016年4月23日，英国《柳叶刀》主编理查德·霍顿（Richard Horton）发表时评：医学与营养——不可理喻（直译：疯狂、患精神病、精神失常、精神错乱、愚蠢、荒唐，还被用于命名《魔兽争霸3：冰封王座》的多人对战地图包）。
医学极境（Limits in medicine）就用词而言似乎自相矛盾。医学不断进步、打破陈规、开创新的可能，其中一些成功引人注目而其他仅仅是逐步向前，或走入过度乐观的死胡同，或（极少）虚假捏造。因此，将会议命名为“极境”的想法似乎完全正确又名不副实。说它正确，是因为在突破边缘进行知识辩论即为医学内涵。说它名不副实，是因为医学没有“极”，不可能处于不存在的“境”。有人可能会说，医学被定义为在可接受的认知范围内不断地越界。例如，最近有一篇系统回顾提出血压应降至低于140mmHg的可接受极境，而八十后研究（After Eighty study）发现对于非ST段抬高型心肌梗死老年患者积极干预比保守策略更有效。医学确实存在“极境”。上周，德里克·耶纶（Derek Yellon）教授和朗尼·奥佩（Lionel Opie）教授在伦敦召开了关于“心脏病学、糖尿病学和肾脏病学极境”（Cardiology, Diabetes, and Nephrology At the Limits）的最新学术研讨会，这是了解某些影响人类生命结局最重要疾病获得进展的庆祝活动。
At the Limits
然而，处于“极境”并不怎么好，医学在很多方面并不如其所声称的那样。马吉德·艾萨提（Majid Ezzati）等人（组成了非传染性疾病风险因素协作组）本月展示了这种失败的程度。在一项关于全球200多个国家从1975年至2014年肥胖趋势的研究中，他们发现到2025年每5个男性和女性中将有1个是肥胖者。尽管低体重仍是非洲和南亚部分地区的一个重要问题，但现在世界上肥胖者（6.41亿）多于低体重者（4.62亿）。艾萨提等人认为，“目前的干预措施和政策未能阻止大多数国家人们体重指数的上升”。在第二篇文章中，艾萨提等人研究了世界范围内糖尿病的趋势。他们估计成人糖尿病数量从1980年1.08亿上升至2014年4.22亿。综上，这些结果表明全球肥胖和糖尿病控制目标仍未达到，情况相当糟糕。
Majid Ezzati
萨利姆·尤素福（Salim Yusuf）的前瞻性城乡流行病学（Prospective Urban Rural Epidemiology，PURE）研究发现，四种重要的心血管疾病二级预防药物——阿司匹林、β受体阻滞剂、血管紧张素转换酶抑制剂和他汀类药物，生活在中低收入国家的很多人无法获得或负担不起。此外，获得这些救命药物渠道的全球目标可能被忽视。
Salim Yusuf
是什么造成这种令人沮丧的情况？看看波士顿塔夫茨大学弗里德曼营养科学与政策学院院长达柳什·莫扎法里安（Dariush Mozaffarian）对这个问题的回答，他在今年的《柳叶刀》极境（At the Limits）研讨会上发表了2016年主题演讲。全球疾病负担（Global Burden of Disease）研究发现在美国和全球，饮食是最重要的疾病风险因素。但你永远不知道，这是医学教育对营养的重视程度造成的：医学院几乎没有营养教学。营养并不被常规记录于患者的病案，并且营养干预几乎不被纳入医保。这个领域本身就充满“激情与困惑”：总有“刺耳的声音”自称知道完美饮食的秘密，但是那些自封的专家们看上去几乎不懂营养科学。莫扎法里安认为当前的营养政策落后于最佳营养科学至少10～15年。他说，痴迷于能量平衡、卡路里和脂肪“不可理喻”，其实重要的不是数量而是质量，800卡路里营养饮食远远好于400卡路里不良饮食。他强调了地中海饮食的价值，这是一种以坚果、橄榄油、鱼、水果、蔬菜、酸奶和全谷物为主的饮食。但是，即使是受人尊敬的美国国家卫生研究院（NIH）给出的公众指导也与最佳证据相矛盾。从莫扎法里安的讲话可能得出教训：医学尽管以其学术地位为傲，但仍需深入反思。医生一贯忽视预防科学，营养研究的价值被低估，而且医学似乎安于江湖郎中和骗子盛行，真是不可理喻！
Richard Horton
翻译：肖慧娟（天津市第三中心医院）
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Lancet. 2016 Apr 23;387(10029):1706.
Offline: Medicine and nutrition-"that's insane".
Richard Horton.
Limits in medicine seem a contradiction in terms. Medicine advances continuously, shattering orthodoxies and opening new possibilities, some of which succeed spectacularly while others are mere incremental steps forward, overoptimistic dead ends, or (rarely) deceptive fabrications. The idea of a conference entitled "At the Limits" therefore seems entirely correct and a misnomer. Correct because debating knowledge on the edge of breakthrough is what medicine is about. Misnomer because, since medicine has no limit, one cannot be "at" something that does not exist. What one might say is that medicine is defined by a permanent transgression of boundaries around acceptable understanding. A systematic review recently argued that blood pressure should be reduced below the accepted limit of 140 mm Hg. The After Eighty Study found that aggressive intervention in older patients with non-ST-elevation myocardial infarction was more successful than conservative strategies. Medicine does live at the limits. Last week, Professors Derek Yellon and Lionel Opie convened their latest scientific symposium on Cardiology, Diabetes, and Nephrology At the Limits in London. It was a celebration of progress in understanding some of the most important diseases shaping outcomes for human life.
And yet living at the limit isn't good enough. In too many ways medicine is failing those it claims to serve. Majid Ezzati and his colleagues (who make up the Non-Communicable Disease Risk Factor Collaboration) this month showed the extent of that failure. In a study of trends in obesity across 200 countries from 1975 to 2014, they found that by 2025 around one in five men and women will be obese. Although underweight remains an important concern in parts of Africa and South Asia, more people in the world are now obese (641 million) than underweight (462 million). Ezzati and colleagues conclude that, "Present interventions and policies have not been able to stop the rise in body-mass index in most countries." In a second paper, Ezzati and colleagues looked at worldwide trends in diabetes. They estimated that the number of adults with diabetes rose from 108 million in 1980 to 422 million in 2014. Taken together, these findings suggest that global obesity and diabetes targets will not be reached. The story is considerably worse. Salim Yusuf's Prospective Urban Rural Epidemiology (PURE) study found that four important medicines for secondary prevention of cardiovascular disease (aspirin, β blockers, angiotensin-converting enzyme inhibitors, and statins) were unavailable or unaff ordable for large numbers of people living in middle-income and lowincome nations. Again, global targets for access to these life-saving medicines are likely to be missed.
What accounts for this dismal performance? Some light was thrown on the answer to this question by Dariush Mozaffarian, Dean at Boston's Tufts Friedman School of Nutrition Science and Policy, who delivered the 2016 Lancet lecture at this year's At the Limits symposium. The Global Burden of Disease has found that diet is overwhelmingly the most important risk factor for illness in the US and globally. And yet you would never know this fact based on the seriousness with which nutrition is treated by academic medicine. Nutrition is hardly taught at medical school. It is not routinely captured in a patient's medical record. And nutrition interventions are almost never reimbursed. The field itself is riven with "passion and confusion". There is a "cacophony of voices" claiming to know the secrets of the perfect diet. Yet few self-styled experts seem to understand the science of nutrition. Mozaffarian argued that current nutrition policy was at least 10-15 years behind the best nutrition science. An obsession with energy balance, calories, and fat is "insane", he said. What matters is not quantity but quality. 800 calories of a nutritious diet is far better than 400 calories of a bad diet. He emphasised the value of a Mediterranean regime, one rich in nuts, olive oil, fish, fruits, vegetables, yoghurt, and whole grains. But even public guidance given by the respected US National Institutes of Health contradicts the best evidence. A lesson one might draw from Mozaffarian was that medicine, despite the pride it takes in its scientific status, remains deeply ideological. Physicians consistently ignore prevention science. Nutrition research is undervalued. And medicine seems comfortable allowing quacks and charlatans to prosper. Insane indeed.
PMID: 27116265
DOI: 10.1016/S0140-6736(16)30300-2