Mechanisms of disease

2.2. Natural History

First of all, it is important to understand that diseases have a natural history of progress within the body. Diseases do not always develop in a linear way.  Sometimes there may be ‘jumps’, such as worsening or improvement in health status. For the doctor as well as the patient, it is important to understand this to be able to monitor the effect of a given pharmacotherapy or treatment.

Often disease progression takes place over a long time before any obvious symptoms can be seen. This is due to the organism being able to correct any changes up to certain limits, without affecting the system’s homeostasis as a whole. It is only when these limits are reached that disease symptoms become evident.

Pharmacotherapy can reverse or stop the process, but not repair any destroyed tissues.

As seen in the case with anaemia, the underlying causes for the symptoms are important. The causes and origin of the disease are in medical terms described by the word ‘aetiology’. A patient can be treated either through lifestyle changes and/or through medical intervention such as surgery or pharmacotherapy.