The impact of physical illnesses on non-psychotic psychiatric morbidity: data from the household survey of psychiatric morbidity in Great Britain.

Objectives: Psychiatric morbidity among the physically ill is an important issue, particularly in the light of research documenting the difficulties in accurately diagnosing and effectively treating psychiatric disorders in this group. The objectives of this study were: (1) To compare psychiatric morbidity in 11 physical conditions and a healthy comparison group. (2) To compare psychiatric morbidity between respondents with one of the 11 illnesses to those with more than one physical illness.

Design: The sample was derived from the cross-sectional Household Survey of Psychiatric Morbidity.

Methods: Psychiatric morbidity (excluding psychosis) was assessed by interview using the revised Clinical Interview Schedule (CIS-R) and physical illness through self-report in 10,108 adults.

Results: Eight of the 11 illness groups were more likely to be classified as having psychiatric morbidity on the CIS-R than the physically healthy group. There were no differences in psychiatric morbidity between the different illness groups. The presence of more than one physical illness significantly increased the likelihood of psychiatric morbidity in 10 of the 11 groups.

Conclusions: This study further supports the association between physical and psychiatric illness. Importantly, it suggests an increased likelihood of psychiatric morbidity in the presence of more than one physical condition.