Natural history of functional dyspepsia: a 10-year population-based study.

Background: Functional dyspepsia (FD) is a common disorder, but information on its natural history is limited.

Aim: To study the natural history of FD as assessed by 2 criteria over a 10-year period.

Method: A population-based study conducted by mailing a questionnaire to the same age- and gender-stratified random sample of the Icelandic population aged 18-75 in 1996 and again in 2006. FD was estimated by the Functional Dyspepsia Score List and by dyspepsia subgroups categorized into 4 groups: (1) frequent upper pain, (2) meal-related, (3) nausea or vomiting, and (4) combinations of these groups.

Results: FD was diagnosed in 13.9% of the subjects in the 1996 sample (11.3% male, 15.8% female) and 16.7% in 2006 (12.3% male, 20.2% female) with a significant difference between males and females in 2006. Dyspepsia subgroup criteria showed a higher prevalence than conventional FD criteria. The proportion of FD subjects in one of the dyspepsia subgroups was low. There was a significant relationship between FD and heartburn and irritable bowel syndrome. A high proportion of subjects who seek medical care have FD.

Conclusion: FD was stable over the 10-year period, but there was turnover in symptoms and increased intensity and frequency of gastrointestinal pain. Dyspepsia subgroup criteria showed a higher prevalence than FD, which was more common in young subjects and females. FD poses a heavy burden on the health care system.