在世界的每個地方，人們都比過去更長壽。多虧了科學的進步，更少人會因為心臟病、癌癥和傳染病而英年早逝。一個人到80多歲還能活得很好已不再是稀罕事。我父親就將在幾周后迎來他92歲的生日，活到這個歲數(shù)在他出生的那個年代幾乎是無法想象的。

人類的壽命比以前更長，這應該是一件開心事才對。但如果長壽不能使人開心，那會發(fā)生什么？

你活的時間越長，就越可能出現(xiàn)慢性病的情況。你罹患關節(jié)炎、帕金森病或其它降低你生活質量的非傳染性疾病的風險逐年遞增。不過在所有威脅到我們晚年生活的疾病中，有一種對社會的危害尤為嚴重，那就是阿爾茨海默癥。

你如果活到80多歲，就會有接近50%的可能性得這種病。在美國，阿爾茨海默癥是十大死亡原因之一，卻是其中唯一沒有有效治療手段的死因，每年的發(fā)病率都在增加。隨著美國在“嬰兒潮”時期出生的一代人步入老年，這種趨勢將會繼續(xù)擴大。這意味著有更多的家庭將眼睜睜地看著他們親人的認知能力減退，然后慢慢地消失。盡管疾病負擔越來越重，科學家們還是沒能弄清到底是什么原因導致了阿爾茨海默癥，以及如何才能阻止這種疾病破壞大腦。

我最初對阿爾茨海默癥產生興趣是由于它對家庭和醫(yī)療系統(tǒng)造成的負擔——既是情感上的負擔，又是經濟上的負擔。這種病的經濟負擔更容易量化。比起沒有神經退行性疾病的老年人，患阿爾茨海默癥或其他形式癡呆癥的病人，每年在自費醫(yī)療項目上要多花五倍的錢。與許多患慢性病的人不同，阿爾茨海默癥患者既要支付長期護理的費用，又要負擔直接的醫(yī)療開支。如果你在六七十歲得了這種病，你在接下來幾十年里可能需要昂貴的護理。

這些開支是發(fā)達國家增長最快的醫(yī)療負擔之一。根據(jù)阿爾茨海默癥協(xié)會提供的數(shù)據(jù)，美國人在2017年將花費2590億美元看護那些患阿爾茨海默癥及其它癡呆癥的病人。如果沒有重大突破，在未來幾年甚至幾十年里，這些支出還將繼續(xù)擠壓財政預算。這些問題是世界各國政府都需要考慮的，包括那些中低收入國家——那里的國民預期壽命也在接近全球平均水平，患癡呆癥的人數(shù)正不斷增加。

想要把阿爾茨海默癥造成的人力成本轉化為數(shù)字，這實在是難上加難。這是一種可怕的疾病，它摧毀的不僅是得病的人，而且包括所有愛他們的人。我對此深有感觸，因為我的家族中就有人得過阿爾茨海默癥。眼睜睜地看著你愛的人掙扎著被這種病奪走心智而你卻對此無能為力，我知道那有多么的痛苦。這感覺很像是在經歷你曾經認識的那個人一點點死去的過程。

我的家庭背景并不是我對阿爾茨海默癥產生興趣的唯一原因。但我的個人經歷確實讓我明白，當你或你愛的人患上這種疾病時，那種感覺有多絕望。我們已經看到科學創(chuàng)新的力量，它將像艾滋病毒這樣曾經不可一世的殺手，轉變成為可以通過服藥被控制住的慢性疾病。我相信我們對阿爾茨海默癥也能做到這一點（或者做得更好）。

過去一年，我花了大量時間研究這種疾病和迄今為止取得的進展。在這個領域里，人們正在開展許多了不起的工作，目的是推遲阿爾茨海默癥的發(fā)病時間和減少它對認知能力的影響。我從研究人員、學者、投資人和業(yè)內專家等各方聽到的信息使我信心滿滿，只要我們可以在五個領域取得進展，我們基本上就能改變阿爾茨海默癥的發(fā)展方向。

• 我們需要更深入地了解阿爾茨海默癥是如何發(fā)生的。大腦是一個復雜的器官，由于病人在世的時候很難對大腦進行研究，我們對它如何隨著年齡老化，以及阿爾茨海默癥如何破壞了這個過程知之甚少。我們對大腦狀況的認識大部分來自于尸體解剖，所以只能看到阿爾茨海默癥末期的表現(xiàn)，而無法解開其長久以來的謎團。例如，我們無法完全理解為什么非洲裔美國人或拉丁美洲人要比白人更容易患阿爾茨海默癥。如果想要取得進展，我們就需要更好地了解這種病的深層次原因和生物學原理。

• 我們需要更早地檢查及診斷阿爾茨海默癥。由于最終確診阿爾茨海默癥的唯一方法是通過死亡后的尸檢，我們很難在病程早期就準確地識別出這種疾病。雖然有認知測試這種方法，但結果往往變動很大。如果你前一晚沒睡好，這可能會影響你的結果。如果有一種像驗血一樣更加可靠、價格可負擔和容易獲得的診斷方法，我們就能更容易地了解阿爾茨海默癥的進展和追蹤新藥物起作用的方式。

• 我們需要更多對抗疾病的方法。一種阿爾茨海默癥藥物可能通過不同的方式預防疾病或減緩疾病發(fā)展。截至目前，大部分的藥物試驗都瞄準了β淀粉樣蛋白和tau蛋白，這是兩種造成大腦斑塊和纏結的蛋白。我希望這些方法能夠成功，但萬一它們不成功，我們需要為科學家們提供些不一樣的、不那么主流的想法。一個更加多樣化的新藥產品線將有助于提高發(fā)現(xiàn)突破性解決方案的機會。

• 我們需要讓人們更容易地參與臨床試驗。創(chuàng)新的步伐有多快，部分取決于我們能多快地進行臨床試驗。由于我們對阿爾茨海默癥了解不多，也沒有一種可靠的診斷方法，所以很難找到處于病程早期且愿意參與臨床試驗的合適人選。招募到足夠的患者可能需要數(shù)年的時間。如果可以找到一種方法來預先選定參與者并創(chuàng)建有效的注冊體系，我們就可以更快地開展新的試驗。

• 我們需要更好地利用數(shù)據(jù)。每當制藥公司或實驗室進行一項研究時，他們都會收集大量信息。我們應該用一種通用的格式來編譯這些數(shù)據(jù)，以便更好地了解阿爾茨海默癥如何發(fā)病、發(fā)病情況怎樣受性別和年齡影響，以及遺傳基因如何對患病幾率造成影響。這將使研究人員更容易尋找模式和發(fā)現(xiàn)治療的新途徑。

如果我們在以上這些領域都能取得進步，我想我們就能開發(fā)出一種干預措施，從而極大地減小阿爾茨海默癥的影響。我們有足夠的理由對前景保持樂觀：我們對大腦和阿爾茨海默癥的了解正在突飛猛進地發(fā)展。我們已經取得了一些成果，但還需要做得更多。

我想要支持有才華的人從事這項工作。作為第一步，我向癡呆癥發(fā)現(xiàn)基金（Dementia Discovery Fund）投資了5000萬美元，這是一個致力于增加臨床藥物種類和發(fā)現(xiàn)治療新目標的私募基金。大型制藥公司中的大多數(shù)還在繼續(xù)尋求β淀粉樣蛋白和tau蛋白治療方法。癡呆癥發(fā)現(xiàn)基金是制藥公司的有益補充，它支持一些初創(chuàng)公司去探索不那么主流的方法治療癡呆癥。

我所做的這筆投資是以個人的名義，而不是通過基金會。要想實現(xiàn)阿爾茨海默癥首次被成功治愈，這或許要等十年甚至更長的時間，而且最開始的治療也一定會非常昂貴。等到那天來臨的時候，我們的基金會可能會考慮如何把它推廣到貧困國家。

不過在開始考慮各種做法之前，我們還是需要先實現(xiàn)許多科學突破。所有正在研發(fā)過程中的新工具和新理論都讓我相信，我們正處在一個阿爾茨海默癥研發(fā)事業(yè)的轉折點?，F(xiàn)在正是加快進步的時候，從而避免讓阿爾茨海默癥造成的巨大損失沖擊到那些無法負擔高昂醫(yī)藥費的國家。在那些國家，阿爾茨海默癥流行對財政預算的影響，足以導致整個醫(yī)療系統(tǒng)破產。

這是一個可以大幅提高人類生存質量的前沿領域。人類壽命越來越長是一個奇跡，但只有更長的預期壽命是不夠的。人們應該享受自己的晚年生活，為了實現(xiàn)這一點我們要在阿爾茨海默癥方面取得突破。我很激動能加入對抗這一疾病的戰(zhàn)斗，同時迫不及待地想要看看接下來會發(fā)生什么。

Why I’m Digging Deep Into Alzheimer’s 

In every part of the world, people are living longer than they used to. Thanks to scientific advancements, fewer people die young from heart disease, cancer, and infectious diseases. It’s no longer unusual for a person to live well into their 80s and beyond. My dad will celebrate his 92nd birthday in a couple weeks, a milestone that was practically unimaginable when he was born. 

This fact—that people are living longer than ever before—should always be a wonderful thing. But what happens when it’s not? 

The longer you live, the more likely you are to develop a chronic condition. Your risk of getting arthritis, Parkinson’s, or another non-infectious disease that diminishes your quality of life increases with each year. But of all the disorders that plague us late in life, one stands out as a particularly big threat to society: Alzheimer’s disease. 

You have a nearly 50 percent chance of developing the disease if you live into your mid-80s. In the United States, it is the only cause of death in the top 10 without any meaningful treatments that becomes more prevalent each year. That trend will likely continue as baby boomers age, which means that more families will watch their loved ones suffer from cognitive decline and slowly disappear. Despite this growing burden, scientists have yet to figure out what exactly causes Alzheimer’s or how to stop the disease from destroying the brain. 

I first became interested in Alzheimer’s because of its costs—both emotional and economic—to families and healthcare systems. The financial burden of the disease is much easier to quantify. A person with Alzheimer’s or another form of dementia spends five times more every year out-of-pocket on healthcare than a senior without a neurodegenerative condition. Unlike those with many chronic diseases, people with Alzheimer’s incur long-term care costs as well as direct medical expenses. If you get the disease in your 60s or 70s, you might require expensive care for decades. 

These costs represent one of the fastest growing burdens on healthcare systems in developed countries. According to the Alzheimer’s Association, Americans will spend $259 billion caring for those with Alzheimer’s and other dementias in 2017. Absent a major breakthrough, expenditures will continue to squeeze healthcare budgets in the years and decades to come. This is something that governments all over the world need to be thinking about, including in low- and middle-income countries where life expectancies are catching up to the global average and the number of people with dementia is on the rise. 

The human cost of Alzheimer’s is much more difficult to put into numbers. It’s a terrible disease that devastates both those who have it and their loved ones. This is something I know a lot about, because men in my family have suffered from Alzheimer’s. I know how awful it is to watch people you love struggle as the disease robs them of their mental capacity, and there is nothing you can do about it. It feels a lot like you’re experiencing a gradual death of the person that you knew. 

My family history isn’t the sole reason behind my interest in Alzheimer’s. But my personal experience has exposed me to how hopeless it feels when you or a loved one gets the disease. We’ve seen scientific innovation turn once-guaranteed killers like HIV into chronic illnesses that can be held in check with medication. I believe we can do the same (or better) with Alzheimer’s. 

I’ve spent considerable time over the last year learning about the disease and the progress made to date. There’s a lot of amazing work being done in this field to delay Alzheimer’s and reduce its cognitive impact. What I’ve heard from researchers, academics, funders, and industry experts makes me hopeful that we can substantially alter the course of Alzheimer’s if we make progress in five areas: 

• We need to better understand how Alzheimer’s unfolds. The brain is a complicated organ. Because it’s so difficult to study while patients are alive, we know very little about how it ages normally and how Alzheimer’s disrupts that process. Our understanding of what happens in the brain is based largely on autopsies, which show only the late stages of the disease and don’t explain many of its lingering mysteries. For example, we don’t fully understand why you are more likely to get Alzheimer’s if you’re African American or Latino than if you’re white. If we’re going to make progress, we need a better grasp on its underlying causes and biology. 

• We need to detect and diagnose Alzheimer’s earlier. Since the only way to diagnose Alzheimer’s definitively is through an autopsy after death, it’s difficult to identify the disease definitively early in its progression. Cognitive tests exist but often have a high variance. If you didn’t sleep well the night before, that might skew your results. A more reliable, affordable, and accessible diagnostic—such as a blood test—would make it easier to see how Alzheimer’s progresses and track how effective new drugs are. 

• We need more approaches to stopping the disease. There are many ways an Alzheimer’s drug might help prevent or slow down the disease. Most drug trials to date have targeted amyloid and tau, two proteins that cause plaques and tangles in the brain. I hope those approaches succeed, but we need to back scientists with different, less mainstream ideas in case they don’t. A more diverse drug pipeline increases our odds of discovering a breakthrough. 

• We need to make it easier to get people enrolled in clinical trials. The pace of innovation is partly determined by how quickly we can do clinical trials. Since we don’t yet have a good understanding of the disease or a reliable diagnostic, it’s difficult to find qualified people early enough in the disease’s progression willing to participate. It can sometimes take years to enroll enough patients. If we could develop a process to pre-qualify participants and create efficient registries, we could start new trials more quickly. 

• We need to use data better. Every time a pharmaceutical company or a research lab does a study, they gather lots of information. We should compile this data in a common form, so that we get a better sense of how the disease progresses, how that progression is determined by gender and age, and how genetics determines your likelihood of getting Alzheimer’s. This would make it easier for researchers to look for patterns and identify new pathways for treatment. 

By improving in each of these areas, I think we can develop an intervention that drastically reduces the impact of Alzheimer’s. There are plenty of reasons to be optimistic about our chances: our understanding of the brain and the disease is advancing a great deal. We’re already making progress—but we need to do more. 

I want to support the brilliant minds doing this work. As a first step, I’ve invested $50 million in the Dementia Discovery Fund—a private fund working to diversify the clinical pipeline and identify new targets for treatment. Most of the major pharmaceutical companies continue to pursue the amyloid and tau pathways. DDF complements their work by supporting startups as they explore less mainstream approaches to treating dementia. 

I’m making this investment on my own, not through the foundation. The first Alzheimer’s treatments might not come to fruition for another decade or more, and they will be very expensive at first. Once that day comes, our foundation might look at how we can expand access in poor countries. 

But before we can even begin to think about how we do that, we need lots of scientific breakthroughs. With all of the new tools and theories in development, I believe we are at a turning point in Alzheimer’s R&D. Now is the right time to accelerate that progress before the major costs hit countries that can’t afford high priced therapies and where exposure to the kind of budget implications of an Alzheimer’s epidemic could bankrupt health systems. 

This is a frontier where we can dramatically improve human life. It’s a miracle that people are living so much longer, but longer life expectancies alone are not enough. People should be able to enjoy their later years—and we need a breakthrough in Alzheimer’s to fulfill that. I’m excited to join the fight and can’t wait to see what happens next. 

If you want to receive updates on how I’m getting involved in the fight to stop Alzheimer’s disease, click on the link below and sign up to become a Gates Notes Insider.