Why Do We Know So Little About Disease?

24th November 2017

The most straightforward answer to this question is ‘it is complicated’. Despite the research that scientists undertake to try to unravel the complexity of these and many other diseases, at times it seems that investigations generate more questions than answers.

Research also highlights how little we know about the cause, effect, and progression of diseases that can have on the human body. In today’s world we have fantastic technology that allows us to explore space; communicate and share ideas in real time with people all over the world at the touch of a button. We can even reorder prescribed medications online, but we cannot decipher the randomness and complexity of some of the major diseases that can lead to life-changing effects.

The whole area of knowledge about diseases is incredibly complex and can be discussed on many different levels and from many different viewpoints.

The definition of the term ‘disease’, according to the Oxford dictionary (Oxford Dictionaries · © Oxford University Press)

“a disorder of structure or function in a human, animal, or plant, especially one that produces specific signs or symptoms or that affects a specific location and is not simply a direct result of physical injury”.

In this definition is a clue to one of the factors that govern one reason why we know so little about the causes. The clue is in the wording ‘specific signs or symptoms ‘. Not every disease has specific signs or symptoms, additionally many signs and symptoms of one condition may be similar to, or indistinguishable from another disease.

An excellent example of this is the symptoms of Hypothyroidism which are:

  • Fatigue
  • Weakness
  • Weight Gain
  • Dry, Rough Pale Skin
  • Hair Loss
  • Memory Loss
  • Depression
  • Irritability

These symptoms can be mistaken for clinical depression. If the patient is treated for depression as opposed to hypothyroidism, they may become seriously ill and suffer organ failure, as the thyroid is responsible for making sure that all of the organs in the body work efficiently.


When faced with the signs and symptoms, reported by the patient the physician also needs to find out about the patient’s family medical history as many diseases such as thyroid disease have a genetic link. Additionally, other factors may be involved. Some diseases have the capability of mutating. The prime example of this is influenza, due to its ability to mutate, research may be outdated before the results have had the opportunity to be published. Diseases can also occur at random, so there may be no particular profile that can alert both doctors and researchers to the cause or the effect on a specific individual.

To gain a full perspective of why we know so little about diseases, we need to consider a few statistics.

Statistics that relate to specific diseases:

  • Parkinson’s. ‘The number of people with Parkinson’s in the UK is set to rise by 28% by 2020; research shows that there are currently 127,000 people in the UK with it.
  • Multiple sclerosis. Origins of MS has associations with the Vikings and the colonies that they established in northern Europe where the incidents of MS is the highest. Having Viking genes can make people susceptible to MS.
  • Motor Neurone Disease. Six people a day are diagnosed a day with MND in the UK. Additionally, six people a day in the UK die of MND. At any one time, 5000 adults are affected by MND.

Multi diseases

Other research problems occur because not every patient may have just one disease. Some diseases may be linked, such as:

  • Diabetes; Heart Disease and Retinopathy
  • Asthma: Hay fever and life-threatening allergies
  • Stroke: Stroke and depression

Professor Bruce Guthrie of Dundee University; NHS Research Scotland has highlighted the problem that many physicians experience, as current treatments focus on individual diseases as opposed to multi-diseases. Several issues are apparent when treating multi-diseases as each disease has a prognosis and morbidity rate which will alter when new conditions are present.
Additionally, professor Guthrie has also highlighted difficulties that occur when more than one specialist treats a patient. His research also found that only 23% of Cancer patients had no other long-term disease.

Up until recently, medical research has focussed on individual diseases as opposed to multi diseases. Although research has increased its scope and pace, it is still unable to analyse and process all of the information it collects in a form that most medical practitioners can readily digest and implement in the way of more effective treatments with side-effects.

Research can be expensive both financially and in human resources. In some circumstances, it may be hard to find the funding for research that replicates other studies. By revisiting research that has already taken place, doctors can aim to improve the quality of care already by basing it on scientific evidence.

When asking ‘why do we know so little about diseases‘, consideration also needs to be given to what do we need to know. Despite the hard work and effort that medical researchers are involved with, it seems that generally, we know very little about some diseases. The reason for this could be that information about a particular illness is only sought when it affects someone close to you, or it affects you.

Although there has been a considerable amount of research information available, is it accessible and can it be easily understood. Most people who want to know about a specific disease will have access to the internet or have a friend or family member that can access the information for them.

Information is well presented and will be able to highlight some of the information that most people have. Information is available, but it may not actually provide answers to the questions.

  • What do we want the research to tell us?
  • What are the expectations of the research?
  • What do we want to know?
  • What treatments are available?
  • Are there alternative treatments or therapies?
  • Is there an accurate prognosis?
  • What is the reliability and validity of the prognosis?
  • What are the factors or variables that may influence my recovery?
  • What caused me to have this disease?

Research is ongoing and relentless in striving to answer these questions, they may never be thoroughly explained. There are many variations and combinations of genetic diseases; differing factors such as environment and ethnicity; mutations of elements of a disease; general randomness and complications that arise from a multi-disease diagnosis that research may never actually be able to give a definitive answer. Guesstimates based on clinical experience and scientific study may be a complete response to the questions.