BACKGROUND:

Little is known about the distribution of diagnoses that account for fatigue in patients in primary care. We evaluated the diagnoses established within 1 year after presentation with fatigue in primary care that were possibly associated with the fatigue.

METHODS:

We conducted a prospective observational cohort study with 1-year follow-up. We included adult patients who presented with a new episode of fatigue between June 2004 and January 2006. We extracted data on diagnoses during the follow-up period from the patients' medical records as well as data on pre-existing chronic diseases.

RESULTS:

Of the 571 patients for whom diagnostic data were available, 268 (46.9%) had received one or more diagnoses that could be associated with fatigue. The diagnoses were diverse and mostly included symptom diagnoses, with main categories being musculoskeletal (19.4%) and psychological problems (16.5%). Clear somatic pathology was diagnosed in 47 (8.2%) of the patients. Most diagnoses were not made during the consultation when fatigue was presented.

INTERPRETATION:

Only a minority of patients were diagnosed with serious pathology. Half of the patients did not receive any diagnosis that could explain their fatigue. Nevertheless, because of the wide range of conditions and symptoms that may explain or co-occur with the fatigue, fatigue is a complex problem that deserves attention not only as a symptom of underlying specific disease.