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Background Increased rates of visual impairment are observed in people with schizophrenia. Aims We assessed whether genetically predicted poor distance acuity is causally associated with schizophrenia, and whether genetically predicted schizophrenia is causally associated with poorer visual acuity. Method We used bidirectional, two-sample Mendelian randomisation to assess the effect of poor distance acuity on schizophrenia risk, poorer visual acuity on schizophrenia risk and schizophrenia on visual acuity, in European and East Asian ancestry samples ranging from approximately 14 000 to 500 000 participants. Genetic instrumental variables were obtained from the largest available summary statistics: for schizophrenia, from the Psychiatric Genomics Consortium; for visual acuity, from the UK Biobank; and for poor distance acuity, from a meta-analysis of case–control samples. We used the inverse variance-weighted method and sensitivity analyses to test validity of results. Results We found little evidence that poor distance acuity was causally associated with schizophrenia (odds ratio 1.00, 95% CI 0.91–1.10). Genetically predicted schizophrenia was associated with poorer visual acuity (mean difference in logMAR score: 0.024, 95% CI 0.014–0.033) in European ancestry samples, with a similar but less precise effect that in smaller East Asian ancestry samples (mean difference: 0.186, 95% CI –0.008 to 0.379). Conclusions Genetic evidence supports schizophrenia being a causal risk factor for poorer visual acuity, but not the converse. This highlights the importance of visual care for people with psychosis and refutes previous hypotheses that visual impairment is a potential target for prevention of schizophrenia.

BackgroundDementia diagnosis rates are increasing. Guidelines recommend that people with dementia should be told their diagnosis clearly and honestly to facilitate future planning.AimsTo analyse how doctors deliver a dementia diagnosis in practice.MethodConversation analysis was conducted on 81 video-recorded diagnosis feedback meetings with 20 doctors from nine UK memory clinics.ResultsAll doctors named dementia; 59% (n = 48) approached the diagnosis indirectly but delicately (‘this is dementia’) and 41% (n = 33) approached this directly but bluntly (‘you have Alzheimer's disease’). Direct approaches were used more often with people with lower cognitive test scores. Doctors emphasised that the dementia was mild and tended to downplay its progression, with some avoiding discussing prognosis altogether.ConclusionsDoctors are naming dementia to patients. Direct approaches reflect attempts to ensure clear diagnosis. Downplaying and avoiding prognosis demonstrates concerns about preserving hope but may compromise understanding about and planning for the future.Declaration of interestNone.