As mentioned throughout these articles, adrenal adenoma is considered to be a rather rare disease. Of course, it may be difficult to subsequently define "rare" in terms of incidence rates. From the Euopean-centred approach to such diseases, "rare" is defined as having an incidence of one on two thousand cases or less. However, it is important to appreciate the fact that as the vast majority of adenomas are benign in their nature and are therefore asymptomatic, many cases will go undetected. The assumption here is that there is a strong possibility that adrenal adenomas are indeed more common than suspected. However, until this observation is supported by further research, we shall still consider adenomas to be quite rare in the typical sense.
As with most benign (and malignant) growths, age will play a pronounced role in the incidences and the onset of adrenal adenoma. While it is rare to witness adenomas in children or those under the age of fifty, occurrences will increase in the fifth and sixth decades of one's life. This may also be due to the fact that a benign growth may not increase in its size or begin to affect hormonal levels until these decades.
Most scientists do not yet fully understand if gender plays a role although there have been some studies which suggest the incidence of adrenal adenomas are slightly higher in women. There is ongoing research to determine as to whether or not menopause plays a significant (if any) role in its occurrence.
There is not yet enough evidence to support the belief that lifestyles affect prevalence rates. However, there has been some extrapolation that obesity, poor diet, an increased consumption of alcohol and a sedentary lifestyle may place patients at a slightly higher risk. As with most benign and malignant growths, it is strongly believed that smoking cigarettes may indeed play a substantial role in increasing one's chances of developing adrenal adenoma later in life. As of the present, there have been no specific chemicals that are seen to discreetly cause this disease.
It is known that stress plays an important part in regulating many of the body's internal functions. This is particularly important to note with the adrenal glands, for one of the main hormones produced is cortisol. This is a chemical directly related to an autonomic stress response. It is believed that those who produce excess amounts of this hormone may be at a slightly higher risk for developing an adenoma over time.
As mentioned earlier, certain genetic disorders and chromosomal abnormalities play a definite role in the chances of one being diagnosed with adrenal adenoma later in life. However, these conditions themselves are quite rare and should one be diagnosed with such illnesses, ongoing scans to detect an adenoma may be warranted.
It is important to realise that incidence and prevalence are different factors. For example, the flu can be considered to be an illness with a high incidence and yet a low prevalence (because it is a short-lived sickness). Conversely, the prevalence of adenomas may be higher than suspected (due to their rather benign nature) while their incidence rates (when they are detected) will remain quite low.