Co-morbid anxiety disorders in patients with schizophrenia in a tertiary institution in South East Nigeria: prevalence and correlates.
Background: Anxiety disorders occur commonly in schizophrenia but are often overlooked by psychiatrists. Their presence may compound the challenges faced by these patients and may contribute to poor outcome.
Objectives: The purpose of this study was to determine the prevalence of anxiety disorders among the participants with schizophrenia, and the association between this co-morbidity and disability.
Method: A total of 367 participants were recruited from the out-patient department of Federal neuropsychiatric hospital Enugu, Nigeria. Socio-demographic questionnaire, schedules for clinical assessment in neuropsychiatry, positive and negative syndrome scale and the 12-item version of the World Health Organization disability assessment schedule were administered.
Results: A total of 189 females (51.5%) and 178 (48.5%) males were studied. A lifetime prevalence of 12.3% was reported for anxiety disorder. Anxiety disorder was more likely in females (κ²=4.93, p<0.03). Specific prevalence for anxiety disorder in schizophrenia was generalized anxiety disorder 6.3%, obsessive compulsive disorder 3.3%, and phobic anxiety disorder 2.7%. Anxiety disorder was associated with increased disability (t=3.50, p<0.001) and psychopathology (t=3.40, p<0.001) among the participants studied. Phobias were associated with prescription of low doses of antipsychotics (κ²=4.08, p<0.04). There was a low rate of identification of anxiety disorder in routine clinical practice (k=0.08, p<0.001).
Conclusion: Co-morbid anxiety disorders are common in schizophrenia and they are associated with increased disability and psychopathology. The results emphasize the need to screen for anxiety disorders in patients with schizophrenia.
Key words: schizophrenia, anxiety disorder, co-morbidity.