| Abstrakt: |
Background Existing literature on anxiety in schizophrenia is confined to well-established diagnostic syndromes as defined independently from and outside the context of schizophrenia. It is not known yet whether anxiety that is not differentiated into these syndromes (that is, undifferentiated anxiety) is empirically discernible from syndromal anxiety in acute phase schizophrenia and whether it amounts to an entity discernible from no anxiety. Methods The study compared anxiety features among 111 participants in an acute phase of schizophrenia, stratified into three groups after sampling. One group met DSM-IV diagnostic criteria for one or more of the syndromal anxiety disorders irrespective of having undifferentiated anxiety features concurrently. The second group did not meet DSM-IV diagnostic criteria for anyone of the syndromal anxiety disorders yet qualified for the DSM-IV diagnosis of anxiety disorder not otherwise specified. The third group comprised patients who did not meet DSM-IV diagnostic criteria for any syndromal anxiety disorder, nor for an anxiety disorder not otherwise specified. The groups were stratified by using the SCID either directly for patients who participated in the SCID-I, or indirectly through statistical modelling for patients without SCID-data. Analyses were performed respectively for a SCID-data set and a replicative data set. The groups were compared for anxiety, psychotic severity, depressive features, akathisia and medication use. Results On two measures of anxiety and for both data sets, the groups were statistically significantly different. The undifferentiated anxiety group was statistically significantly different from the syndromal group on the Staden Schizophrenia Anxiety Rating Scale (S-SARS) for both data sets (SCID-data set: mean difference=7.46, 95% Confidence Interval (CI) = 3.73 to 10.98, p<0.001; Replicative data set: mean difference=7.69, 95% CI=3.97 to 11.24, p<0.002). This difference was also found on the Hamilton Anxiety Scale (HAM-A) for the SCID-data set (mean difference=14.68, 95% Confidence Interval (CI)= 10.34 to 19.21, p<0.001) but not for the replicative data set (mean difference=1.49, 95% CI=-2.51 to 4.78, p=0.494). The undifferentiated anxiety group was also statistically significantly different from the no anxiety group for both data sets on the S-SARS (SCID-data set: mean difference=8.67, 95% CI=5.62 to 11.58, p<0.001; Replicative data set: mean difference=8.64, 95% CI=4.74 to 12.47, p<0.001), as well as on the HAM-A (SCID-data set: mean difference=6.05, 95% Confidence Interval 4.16 to 8.09, p<0.001; Replicative data set: mean difference=8.67, 95% Confidence Interval 4.22 to 12.68, p=0.002). For both data sets, the groups were not statistically different for akathisia and medication use, nor were the group comparisons confounded by psychotic severity. Depressive features were not a significant confounder in the group comparisons for the replicative data set. Although they were significant for the SCID-data set, the confounding effect was negligible. Discussion The results suggest some patients in acute phase schizophrenia present with undifferentiated anxiety that is discernible from both syndromal anxiety and those without any anxiety. The main finding may serve as empirical foundation for clinicians to recognize undifferentiated anxiety in acute phase schizophrenia. It may also serve as foundation for subsequent research into the clinical importance of undifferentiated anxiety in this population. [ABSTRACT FROM AUTHOR] |
