Schizophrenia Daily News Blog

Rate of Psychotic Disorders May Exceed 3%

"Psychotic disorders are among the most severe and impairing conditions; with a lifetime prevalence exceeding 3%, these disorders are a major public health concern," say investigators reporting in the Archives of General Psychiatry on statistics applied to rates in Finland. These findings indicate a rate of psychotic and bipolar I disorders higher than previously thought.

The life-time prevalence of schizophrenia-related disorders in Finland were determined to be 1.26%.

Statistics for psychotic disorders included diagnoses of schizophrenia (0.87%), schizoaffective disorder(0.32%), schizophreniform disorder (0.07%), delusional disorder (0.18%), bipolar I disorder (0.24%), major depressive disorder with psychotic features (0.35%), substance-induced psychotic disorders (0.42%) and psychotic disorders due to a general medical condition (0.21%).

Investigators Jonna Perälä and colleagues, using multiple sources of information, believe that their method for estimating the prevalence of psychotic disorders is more accurate than those used in previous studies.

PsychiatryMatters.MD explains the investigators' robust method as first screening patients using national healthcare registers along with the Composite International Diagnostic Interviews, self-reported diagnoses, and medication examinations. Those selected were then re-interviewed with the Structured Clinical Interview for DSM-IV and diagnoses were made based on the interview and case note findings.

The authors concluded that the National Hospital discharge register was the most reliable screening process but that additionally supplementing diagnostic interviews with case notes was essential for diagnosing specific psychotic disorders. Perälä et al. conclude:

"Multiple sources of information are essential for accurate estimation of lifetime prevalences of psychotic disorders. The use of comprehensive methods reveals that their lifetime prevalence exceeds 3%."

Read the Article: Psychotic disorders are 'major public health concern'
Full Source Article: Lifetime Prevalence of Psychotic and Bipolar I Disorders in a General Population (Arch Gen Psychiatry 2007; 64: 14-16, 19-28)

Additional Reading:
New Study on the Causal Factors in Schizophrenia Prompts Concern
Schizophrenia Cases Over-estimated?