Effectiveness of pharmacotherapies for delusional disorder in a Swedish national cohort of 9076 patients.

BACKGROUND

Little is known on the effective pharmacological treatment of delusional disorder.

AIMS

Study the comparative effectiveness of pharmacotherapies in the prevention of hospitalization due to psychosis and work disability in delusional disorder.

METHODS

Observational registry based cohort study including everyone in Sweden diagnosed with delusional disorder (N = 9076;mean follow-up time 4.9 years). The primary analysis was Cox Proportional Hazards within-individual analysis. Results are reported as adjusted hazard ratios (HRs).

RESULTS

Among the cohort (4835 males/4241 females;mean [SD] age 44.1 [12.5] years), 2074 persons had at least one hospitalization due to psychosis. Risk for hospitalization due to psychosis was 46% lower when any antipsychotic was used (HR 0.54, 95%CI 0.38-0.77, p < 0.001). Use of clozapine (HR 0.24, 95%CI 0.07-0.77, p = 0.016), any long-acting injectable (LAI; HR 0.28, 95%CI 0.16-0.49, p < 0.0001) and oral olanzapine (HR 0.36, 95%CI 0.20-0.67, p = 0.001) were associated with lowest risk. Among those not on disability pension at start of follow-up (n = 5025), in comparison to no use of antipsychotics, use of clozapine (HR 0.08, 95%CI 0.01-0.52, p = 0.008), any LAI (HR 0.44, 95%CI 0.25-0.79, p = 0.006) and oral aripiprazole (HR 0.52, 95%CI 0.31-0.85, p = 0.009) were associated with lowest risk of work disability.

CONCLUSIONS

Use of antipsychotics was associated with a reduced risk of hospitalization due to psychosis and work disability in delusional disorder, with use of clozapine and long-acting injectables being associated with the lowest risk for these very relevant end-points for both individual suffering and costs to society. Clinical trials with these treatments are urgently needed to make informed clinical treatment recommendations.