Though high discontinuation rates for antipsychotics (APs) by patients with schizophrenia are frequently reported, the percentage of patients receiving pharmaceutical treatment for schizophrenia in routine practice in accordance with international clinical guidelines is unknown. Further, it is unknown if these rates are influenced by levels of neighbourhood deprivation or by a patient's age or sex. Our study aims to investigate if inequalities in AP treatment could be observed between patients living in neighbourhoods with the highest levels of material and social deprivation and those with the lowest deprivation levels, between patients from different age groups, or between men and women.
Methods:
We conducted a secondary analysis of medical-administrative data of a cohort of adult patients in the province of Quebec with a medical contact for schizophrenia in a 2-year period (2004–2005). We assessed the proportion of patients that filled at least 1 prescription for an AP and received adequate pharmaceutical treatment, defined as being in possession of APs at least 80% of the time as outpatients during a 2-year follow-up period.
Results:
Among the 30 544 study patients, 88.5% filled at least 1 prescription for an AP, and 67.5% of the treated patients received adequate treatment. Though no clinically significant differences were observed by deprivation or sex, younger age was associated with lower proportions of patients receiving adequate treatment (46% of treated patients aged between 18 and 29 years, compared with 72% aged between 30 and 64 years, and 77% aged 65 years and over).
Conclusions:
In Quebec's routine practice, over 70% of treated patients aged 30 and over received adequate pharmacological treatment, regardless of sex or neighbourhood socioeconomic status. In contrast, in patients aged between 18 and 29 years this percentage was 47%. This is a discouraging finding, especially because optimal treatment in the early phase of disease is reported to result in the best long-term outcomes.
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