**7. Prevalence**

The prevalence and gender distribution are very variable in venous disorders. Although recent studies have not reported prevalence differences related to age in men and women, most studies demonstrate a higher prevalence in women than men [27].

The prevalence of CVI is lower in African and Asian or Australian aboriginal populations. Changes in lifestyle and eating habits in the industrialized countries (especially a low-fiber diet causing constipation) and abdominal pressure are considered as one of the main causes of this phenomenon [30].
