Disease, disorder, condition, syndrome – what’s the difference?

I’m sure you’re familiar with the basic concepts of diseases, disorders, syndromes, and conditions.

The terms are often used interchangeably – but they actually have different meanings.

And, for some of us – especially for those who English is a second language – describing what a disease is and how it differs from a disorder, syndrome or condition can be quite difficult.

So, what IS the difference?

Read on to learn how to understand and define diseases, disorders, syndromes, and conditions.

What is a disease?

One of the original definitions of a disease was published in the British Medical Journal as early as 1900.

Today, doctors treat and diagnose a disease based on abnormalities in systemic functions – for example, cardiovascular disease.

These abnormalities can cause both physical and emotional signs and symptoms, as well as pain, dysfunction, distress, social problems or death.

What is a disorder?

While doctors diagnose and treat a disease, a disorder is defined as follows.

For example, a disorder resulting from cardiovascular disease is an arrhythmia or irregular heartbeat. An arrhythmia is not a disease itself – it’s an abnormal heartbeat that occurs as a result of having cardiovascular disease.

Disorders can be classified into the following areas:

• Mental
• Physical
• Genetic
• Emotional
• Behavioural
• Structural

What is a syndrome?

A syndrome is a term that refers to a disease or a disorder that has more than one identifying feature or symptom.

In other words, a syndrome is defined as follows:

Down syndrome is a well-known genetic syndrome.

It is characterised by having an extra copy of chromosome 21 in combination with a number of distinctive physical features at birth.

Medical syndromes can be caused by genetic mutations or other factors.

What is a condition?

Sometimes, a syndrome can be caused by a number of diseases or it can be a medical condition itself.

For example, chronic fatigue syndrome is a neurological condition, diagnosed from a collection of symptoms in addition to the main symptom of post-exertional malaise.

Further reading

If you need to assess your writing to ensure you’re communicating about diseases, disorders, conditions and syndromes accurately, here are more resources to help.
The AMA Style Insider provided a comprehensive overview of the origins of disease, condition and disorder which you can read here.

You can also read this overview on DifferenceBetween.com and this Quora discussion if you want to investigate some other perspectives on the topic.

Remember:

• A disease is a pathophysiological response to internal or external factors.
• A disorder is a disruption to regular bodily structure and function.
• A syndrome is a collection of signs and symptoms associated with a specific health-related cause.
• A condition is an abnormal state of health that interferes with normal or regular feelings of wellbeing.

Do you have trouble articulating the differences between diseases, disorders, syndromes and conditions?