4 Great Medical Advances of the Next 30 Years
The last hundred years have seen many great achievements for the human race – a man on the moon, the development of the internet, and a majority of the world’s population living in democratic countries, to name just a few.
But perhaps the greatest triumph has been the advance of modern medicine. In 1900, a third of all children died before the age of 5. A hundred years later, it was less than one in 10, and that number continues to fall. The 20th century saw the elimination of smallpox, one of the most deadly diseases that the world has ever faced. While that century also saw the appearance of HIV/AIDS, a disease that still kills millions worldwide, it’s now the case that where proper medical treatment is available, a diagnosis of HIV/AIDS is no longer a death sentence. There have been countless more such advances.
What’s more, the rate of progress hasn’t slowed. Although the problems in medicine that remain to us are in many cases the thornier ones, and life expectancy in developed countries isn’t increasing at the rate it once was (though it does continue to increase), it seems likely that the next hundred years will see as many remarkable medical advances as the last hundred years did. Looking as much as a hundred years into the future is tricky – could anyone in 1917 have predicted the world today? – but here’s a look at the medical advances we can expect to enjoy in the next few decades if progress continues.
1. A disease-modifying treatment for dementia
In 1906, Alois Alzheimer became the first person to identify and describe the disease that we now know as Alzheimer’s disease, when he observed a patient named Auguste Deter in a local asylum who had symptoms such as memory loss, confusion and disorientation. Dementia is the umbrella term for this set of symptoms, of which Alzheimer’s disease is the most common cause. Many people (usually those without close contact to anyone with dementia) believe that dementia is a natural part of ageing, but in fact it can clearly be linked to specific diseases with associated changes in the brain.
The 20th and 21st centuries to date have seen some progress in treating dementia. We now have a better idea of how to care for people with dementia, what provokes their confusion and agitation, and a better understanding too of risk factors for the various diseases that cause dementia. Best of all, we have developed drugs that help alleviate the symptoms of dementia, especially Alzheimer’s. Alzheimer’s disease damages nerve cells in the brain, but existing drugs help boost the effectiveness even of damaged nerve cells, so that symptoms are alleviated, at least for a time.
But none of these developments actually affect the diseases that cause dementia. Think about a common condition like tonsillitis. You can take aspirin or gargle salt water to alleviate the symptoms; but you need to take antibiotics if you want to tackle the disease itself. For dementia, we have the equivalent of aspirin or salt water – but we don’t have anything like an antibiotic. The technical term of this is a ‘disease-modifying’ treatment. And we need one soon, because Alzheimer’s disease alone killed 1.9 million people in 2015 – that’s more than died from HIV/AIDS (1.2 million). The biggest risk factor for dementia is age, so these numbers will only climb as the world population ages.
The World Health Organisation, the United Nations’ international public health agency, recognises the seriousness of this need. They’ve committed to a dementia action plan that would see the first disease-modifying treatment developed by 2025, which would mean that such a treatment would need to be in phase 2 or phase 3 trials right now. There are around a hundred dementia treatments for which that is the case. That makes the 2025 goal an ambitious, but achievable one – and once the first disease-modifying treatment for dementia exists, it’s likely that drug companies will increase their investment in this underfunded area, and progress will accelerate. It’s highly likely that the first person to survive dementia has already been born.
2. The end of polio
Polio is a disease that’s existed for all of human history – there’s a depiction from Ancient Egypt from 1403-1365 BC that shows a priest with what appear to be the symptoms of childhood polio – that became dramatically more widespread with the growth of cities in the late 19th and early 20th centuries. It’s a viral disease that begins with headache and fever, but that in a minority of cases results in paralysis or death. When epidemics of polio were commonplace in the UK in the 1950s and 1960s, they could result in up to a thousand deaths per year. At its peak, polio was one of the most feared childhood diseases.
There is still no cure for polio, though treatments to speed recovery and ease any resulting paralysis are available. But polio went from a peak of hundreds of thousands of cases worldwide to just 42 last year. The reason was a determined and committed worldwide vaccination programme. The first vaccines were developed in the 1950s and became widely available in the 1960s. Chances are, if you’re reading this today, you’ve been vaccinated against polio as a child yourself.
In 1988, the World Health Organization, UNICEF, and The Rotary Foundation committed to the complete eradication of polio worldwide through vaccination. They targeted complete elimination by 2000, which proved optimistic, but their efforts worked. In 1994, the Americas were declared polio-free; in 2002, Europe; in 2014, South-East Asia. The civil war in Syria halted the vaccination programme and the number of polio cases there began to rise again – but the WHO declared the renewed spread of polio a world health emergency, and vaccinators returned to Syria despite the danger. Several were killed, but polio was eliminated in the country once more.
It’s now the case that just two countries in the world have cases of polio: Afghanistan and Pakistan. In Afghanistan, cases of polio continue to fall as vaccination spreads; it helps that there is widespread support for vaccination despite the civil war. In Pakistan, the situation is more difficult – there’s suspicion of Western vaccinators (it doesn’t help that the CIA has sent operatives posing as vaccinators in the past) and 66 vaccinators were killed in 2013-14. But with so few remaining cases even there, the hope remains that as soon as 2018, polio will join smallpox as a horrific killer that global cooperation has eliminated completely.
3. No more deaths from breast cancer
Cancer of various kinds has been documented all the way back to 3000 BC, and many animals can get cancer too. There are Ancient Egyptian manuscripts that describe breast cancer and note that there is no treatment for it. The Romans attempted surgery to treat cancer, but knew that in many cases the cancer would return all the same – making the dangers of surgery without anaesthetic or any understanding of hygiene a last resort. From the 16th century onwards, advances in medical research (in particular, dissection) increased our understanding of the nature of cancer. We also began to identify risk factors; it’s long been observed that nuns get cancer at a much higher rate than women in the general population, indicating the role of pregnancy and associated hormonal changes in protecting against cancer. In 1775, British physician Percival Potts identified that chimney sweeps were at greater risk of cancer. In 1880, the first mastectomy to treat breast cancer was performed.
But it was only in the 20th century that our understanding and treatment of cancer really began to advance. In 1902, the genetic basis of cancer – that damaged DNA leads to uncontrolled cell replication – was identified by German zoologist Theodor Boveri. Marie and Pierre Curie’s discovery of radiation was quickly followed by its use in cancer treatment; within two years of the discovery, two Russian patients with skin cancer were successfully treated with radiation therapy. The use of nitrogen mustard in World War II led to the discovery that it killed rapidly dividing cells, such as cancer cells, which laid the foundation for the development of chemotherapy. From the 1970s, immunotherapy also became an option in cancer treatment.
The combined use of surgery, radiation therapy, chemotherapy and immunotherapy has led to cancer survival rates soaring. In the 1970s, only about half of patients diagnosed with cancer survived for more than five years. Cancer was a taboo subject, too frightening for a diagnosis to be publically discussed. But medical advances as well as a reduction in risk factors (chiefly, the massive decline in the number of people who smoke routinely) have led to survival rates that have changed dramatically for many of the most common cancers. In the UK, between 1971 and 2010, 10-year survival rates for all cancers have gone from 25% to 50%, for bowel cancer from 23% to 55%, for leukemia from 5% to 43% and for prostate cancer from 25% to 84%. For breast cancer, ten-year survival rates have gone from 39% to 77%, and as this is the 7th leading cause of death in the UK for women, any improvement would save a lot of people’s lives. The largest UK breast cancer charity, Breast Cancer Now, believes that it’s achievable that by 2050, everyone who develops breast cancer will live, joining skin cancer and testicular cancer as cancers that are no longer a death sentence if detected and treated in time.
4. Gene editing available for most inherited diseases
Many of today’s deadly diseases are genetic. Cystic fibrosis affects one in every 2,500 babies born in the UK (about 1 in 25 people is a carrier of the gene), causing a disorder that mostly affects the lungs, leading to difficulty breathing and needing to cough up mucus regularly. There’s no known cure, and the average life expectancy for cystic fibrosis is between 42 and 50 years in the developed world.
Or take muscular dystrophy, a related group of diseases that all have a genetic basis, that cause the weakening and breakdown of skeletal muscles over time. In the most common type, Duchenne muscular dystrophy, most boys who have it (as a mutation on the x-chromosome, it only causes mild symptoms in women) are unable to walk by the age of 12; average life expectancy is 26.
Or there’s sickle-cell disease, a group of inherited blood disorders. It’s frequently a case study in genetics, because it results from having two abnormal copies of the haemoglobin gene. People with just one copy of the abnormal gene, inherited from one parent, are less likely to get malaria and experience less severe symptoms if they do get it, with the result that sickle-cell disease is much more common in sub-Saharan Africa and other areas where malaria is endemic than in the rest of the world. But people with two copies of the abnormal gene – one from each parent – have sickle-cell disease, which causes anaemia, swelling of the hands, attacks of pain, bacterial infections and stroke, beginning when the person is less than a year old. In the developed world, people with sickle-cell disease have a life expectancy of 40 to 60 years, but the vast majority of people with the disease live in the developing world, and it kills over 100,000 people annually.
The list goes on – including some variants of breast cancer and early-onset Alzheimer’s disease. Some inherited diseases are already being tackled through gene therapy, which modifies an adult’s genetic makeup by introducing new DNA into their cells. Over 2,000 clinical trials have been carried out, but gene therapies remain experimental.
But what medical technology will be able to do in the future goes far beyond this. Instead of gene therapy, which alters all cells not involved in reproduction and isn’t heritable, we may develop germline engineering, which alters reproductive cells so that the genetic diseases a person has aren’t inherited by their children. Carried out widely enough, this could eliminate genetic diseases altogether as they would no longer be passed on to future generations. Current experiments result in the genes being successfully spliced only in a minority of cases, and in a high number of undesirable random mutations, but some scientists believe germline engineering will become possible to carry out reliably and effectively within the next 20 years, with remarkable results for human life expectancy and quality of life.
Images: old lady’s hands; vaccination; crying women; genes; pills; skull xray