Achalasia: update on the disease and its treatment.

Epidemiology Most studies that evaluate the epidemiology of achalasia are retrospective. Studies on he incidence and prevalence of achalasia come mostly rom the United Kingdom, but there have been also tudies of diverse populations such as Northern Europe, srael, New Zealand, the United States, and Zimbabwe.1–5 hese studies indicate that the incidence is approxiately 1 in 100,000 individuals annually and the prevaence is 10 in 100,000. There is no gender predominance nd the disease can occur at any age, although diagnosis efore the second decade is rare6 and the incidence inreases with age, with the highest incidence in the sevnth decade7 and a second smaller peak of incidence at 0 – 40 years of age.8