Is serious mental illness linked to creativity? This subject has been debated for decades; and belief in the link is fueled by striking examples, such as the poet Sylvia Plath, who suffered from bipolar disorder. But it is relatively rare to find a systematic way of approaching the question, and especially one that might give insight into possible mechanisms underlying any association.
High polygenic risk scores for schizophrenia and bipolar disorder were noted to predict to a small, but significant, extent the likelihood that an individual will enter a “creative” career
Researchers set out to explore this potential link by examining polygenic risk scores derived from Psychiatric Genomics Consortia.1 Nearly 90,000 members of the general population of Iceland took part in the study. They found that high polygenic risk scores for schizophrenia and bipolar disorder predict to a small, but significant, extent the likelihood that an individual will enter a “creative” career; operationalized by the researchers as being a member of the Icelandic national societies of actors, dancers, musicians, visual artists and writers.1
They found no such relationship for the likelihood of employment in other professions, such as farming, fishing, manual labor or being an executive.
Prediabetic states were found more frequently in people with first episode psychosis than in matched healthy controls
The connection between schizophrenia and type 2 diabetes is another topic which has received much attention. A recent analysis of published studies shows that prediabetic states are found more frequently in people with first episode psychosis (who have not had appreciable exposure to antipsychotics) than in matched healthy controls.2
Shared abnormalities in genes connected to the HLA complex and inflammatory processes – found in genome-wide association studies -- may underlie the connection.
Prior research implicates TNF-α, C-reactive protein and IL 1-β and IL 6 to both schizophrenia and diabetes
In a systematic review and meta-analysis, Benjamin Perry and colleagues from the Universities of Warwick and Birmingham (UK) assessed evidence for the association between first episode psychosis and abnormal control of glycemia.
Pooled analysis of data from 12 studies including over 1000 participants found that – although first episode psychosis is not significantly associated with fasting plasma glucose – it was related to insulin resistance and impaired glucose tolerance.
Young people regarded as at 15-30% risk of developing a full psychotic disorder within a year were randomized to daily 1.4g long-chain omega-3 polyunsaturated fatty acids or paraffin oil placebo.3 Taking PUFAs made no difference to risk of transition to psychosis. However, in both treated subjects and controls, the transition risk was only 11% -- compared with the expected risk of up to 30%.
This suggests that other treatments available to all participants – notably cognitive behavior therapy and SSRIs – may have been effective in reducing ultra-high risk state.