Psychiatry and primary careThe somatization in primary care study: a tale of three diagnoses
Introduction
Somatization has been defined in multiple ways, [1], [2], [3], [4], [5], [6], [7], [8], [9] but generally is understood to mean the occurrence of clinically significant physical symptoms that cannot be entirely explained by physical disease. Somatization occurs frequently in primary care, where up to half of all primary care visits are for somatic complaints and one-third remain unexplained. [10], [11], [12], [13], [14] The diagnosis of somatization disorder (SD) evolved out of the earlier concepts of neurasthenia, hysteria and Briquet’s syndrome. SD was first defined in the DSM-III, based on a lifetime history of unexplained symptoms. [15] The DSM-IIIR modified the criteria to require 13 of a list of 35 lifetime unexplained physical symptoms. [16] The DSM-IV defined a complex algorithm requiring unexplained symptoms from several different categories. [3] Reported prevalence of SD ranges from 0.1% to 16% in various populations, typically about 1–5% in primary care patients. [13], [17], [18] Because many patients who somatize do not meet criteria for full somatization disorder, Escobar proposed and validated a less severe form of somatization called abridged somatization disorder (ASD). [4], [19] ASD is also based on patient recall of lifetime symptoms, requiring at least six unexplained symptoms in women and four in men. Studies report prevalence of ASD ranging from 8 to 37%. [4], [6], [13], [17]
The diagnoses of SD and ASD are made on the basis of lifetime unexplained symptoms. However, the WHO Study of Psychological Problems in Primary Care suggested that recall of lifetime somatic symptoms among somatizing patients is unstable. [20] Although another study indicated that the overall tendency of patients to somatize is a more stable phenomenon, [21] these reports have cast some doubt on the reliability of diagnoses based on recall of lifetime somatic symptoms. Recent investigators have explored the validity of multisomatoform disorder (MSD), which is based on current unexplained symptoms [22], [23]. MSD requires the presence of three or more unexplained symptoms within the past two weeks out of a list of 15, along with a two-year history of somatization. Reported prevalence of MSD in primary care ranges from 4% to 18% [22], [23]. To better understand how the newer diagnosis based on current symptoms relates to older diagnoses based on lifetime symptoms, we examined the diagnostic concordance, impairment, and health care utilization of subjects with SD, ASD, and MSD using data from the Somatization in Primary Care Study, a longitudinal investigation of somatization treatment in a representative population of primary care patients.
Section snippets
Study design
The Somatization in Primary Care Study is a five-year NIMH-funded study conducted in three family practices in or near Mobile, Alabama, USA. Practice sites were selected to achieve geographic and socioeconomic diversity, with one urban practice that serves a racially and economically diverse population, and one suburban practice and one rural practice that both serve higher socioeconomic populations.
The results reported are part of a large randomized controlled trial evaluating the impact of a
Results
A total of 2,902 primary care patients were screened. Fourteen percent of the patients screened were unavailable for enrollment, 6.7% due to refusal and the remainder due to inability to contact or other difficulties. In the enrollment sample of 280 subjects, the estimated prevalence of ASD was 23.0%, MSD was 19.0%, and SD was 5.4%.
Discussion
The Somatization in Primary Care study provides important insights about the overlap among three commonly used somatization diagnoses: full (lifetime) somatization disorder, abridged (lifetime) somatization and (current) multisomatoform disorder. This study demonstrates that the majority of patients who meet diagnostic criteria for MSD also meet criteria for ASD or SD, although the extent of MSD overlap with SD is higher than with ASD. Thus, knowledge of somatization and its treatment derived
Acknowledgements
This work was supported in part by grant MH45441 and MH63651 from the National Institute of Mental Health, Bethesda, MD.
References (50)
Developing practical indexes of somatization for use in primary care
Journal of Psychosomatic Research
(1997)- et al.
The prevalence of somatization in primary care
Compr Psychiatry
(1984) - et al.
Developing a screening index for community studies of somatization disorder
J Psychiatr Res
(1986) - et al.
Screening indexes in DSM-III-R somatization disorder
General Hospital Psychiatry
(1990) - et al.
The cost of somatization
J Psychosom Res
(1991) - et al.
Distressed high utilizers of medical careDSM-III-R diagnoses, and treatment needs
Gen Hosp Psychiatry
(1990) The course of somatization, and its effects on utilization of health care resources
Psychosomatics
(1994)- et al.
Effectiveness of psychiatric intervention with somatization disorder patientsimproved outcomes at reduced costs
General Hospital Psychiatry
(1994) - et al.
Somatization symptoms in the communitya rural/urban comparison
Psychosomatics
(1989) - et al.
Psychiatric disorders in Americathe epidemiologic catchment area study
(1991)