38. INVESTIGATING THE EFFECTS OF PRESCRIBED MEDICATION ON COGNITION OF MEXICAN PEOPLE WITH SCHIZOPHRENIA

Introduction

People with schizophrenia (PwS) experience psychotic (positive and negative) symptoms and along with overall cognitive impairment. Such deficits often predict increased physical comorbidities and a greater degree of disability. While antipsychotic, anticholinergic, psychotropic, and non-psychotropic medications effectively treat symptoms in many PwS, most studies focus predominantly on non-Hispanic White individuals. This focus results in limited evidence regarding the effects of prescribed medications on cognition among Mexican PwS, who may face unique challenges such as cultural stigma and barriers to care that can impact treatment outcomes and cognitive functioning. Notably, research indicates that Latinos experience a higher prevalence of psychotic symptoms compared to non-Hispanic White individuals and are less likely to seek and receive treatment for mental health comorbidities. Efforts to improve the quality of life and health outcomes for PwS have often been ineffective, largely due to the heterogeneity in schizophrenia research. This study aimed to expand the understanding of ethnic differences in the lived experiences of PwS and to develop more tailored interventions. We analyzed medication usage based on Mexican and non-Hispanic White ethnicity and investigated the effects of prescribed antipsychotic and anticholinergic medications on cognition. Furthermore, we explored how sex and ethnicity are related to cognitive functioning in PwS. We hypothesized that 1) Mexican PwS would have higher antipsychotic dosing and anticholinergic burden than non-Hispanic White PwS; 2) Mexican PwS would be more likely than non-Hispanic White PwS to be prescribed antipsychotic, anticholinergic, psychotropic, and antidepressant medications; 3) and larger doses of antipsychotic medication and higher anticholinergic burden would be associated with worse executive functioning and processing speed.

Methods

The study sample included 111 PwS ages 26 to 66 from a completed NIH-funded study that included English-speaking PwS and non-psychiatric controls of Mexican and non-Hispanic White background from the San Diego County area. We collected drug records including current medication, dosage, and type for all participants. We also asked participants about anticholinergic burden, which refers to the overall effects of taking various anticholinergic medications. Additionally, we standardized antipsychotic dosage information using the World Health Organization’s Defined Daily Dose (WHO DDD). We administered the Delis-Kaplan Executive Function System (D-KEFS) to assess domains of cognition, including speed of processing and executive functioning, the Scale for the Assessment of Negative Symptoms, Scale for the Assessment of Positive Symptoms, and the Calgary Depression Scale. Our analyses included T-tests to analyze group and mean differences, logistic regressions to predict the likelihood of medication usage, and general linear models to analyze associations while controlling for ethnicity, sex, education, age, and depression.

Results

Our sample consisted of 111 PwS, of which 42.3% were female and 33.3% were of Mexican ethnicity. The overall sample's mean age was 47.9 years, and the mean education was 12.62 years. When assessing group differences by Mexican or non-Hispanic White ethnicity, we found sociodemographic group differences; specifically, Mexican PwS in our sample were younger, had less years of education, more depressive symptoms, worse executive function, and worse speed of processing. Our results suggest that Mexican PwS have similar antipsychotic dosing (p = 0.86), anticholinergic burden (p = 0.73), and likelihood to be on different classes of medications as their non-Hispanic White PwS counterparts (p > 0.1). Furthermore, we found no significant relationship between antipsychotic dose (p > 0.1) and anticholinergic burden (p > 0.1) on cognitive functioning. Interestingly, Mexican ethnicity was associated with worse cognitive functioning for speed of processing and executive function (p <0.02); fewer years of education (p < 0.005) and older age (p < 0.005) were associated with worse executive function.

Conclusions

Overall, our findings regarding medication dosing and usage align with previous research indicating that prescription practices are similar across ethnic backgrounds. Additionally, our lack of significant links between medications and cognitive functioning reflects the mixed results reported in the literature. The factors contributing to the association between Mexican ethnicity and worse cognitive outcomes remain unclear, underscoring the need for further research into the cultural, biological, and socioeconomic influences that may drive these disparities. Our results aim to inform and refine medication treatments for specific subgroups of PwS, ultimately enhancing cognitive functioning and promoting better overall health outcomes for these populations.