Dysphagia among Schizophrenic Patients:Multivariate Analysis of Risk Factors for Impairment of Swallowing Ability

Abstract

Objective:　The aim of this study was to clarify the risk factors for impaired swallowing function among patients with schizophrenia suffering from dysphagia by using multiple regression analysis.

Patients:　This study was performed retrospectively and included 272 patients with schizophrenia that were referred to the Department of Dentistry and Oral Surgery of our hospital because of swallowing impairment from April 2008 to November 2012. The numbers of male and female cases were 147 and 125, respectively, and the mean age was 68.6 years (standard deviation: 12.7 years). Doses of neuroleptics at the time of assessment of swallowing ability were converted to milligram equivalents of chlorpromazine (CP equivalent dose), and the mean CP equivalent dose at the time of assessment of swallowing ability was 454 mg/day (standard deviation: 603 mg). Swallowing ability of the patients was assessed according to the Functional Oral Intake Scale (FOIS).

Results:　Age, independency of daily living, independency of indoor living, sitting ability, CP equivalent dose and presence or absence of orofacial dyskinesia were assessed as explanatory variables and FOIS as a dependent variable for multiple regression analysis. The results indicated that independency of daily living (p＜0.05), independency of indoor living (p＜0.0001) and sitting ability (p＜0.01) were significantly related with FOIS. However, age (p＝0.990), CP equivalent doses at the time of assessment of swallowing ability (p＝0.092), and presence or absence of orofacial dyskinesia (p＝0.056) were not significantly related to FOIS.

Conclusion:　Swallowing function was significantly related with activity of daily living (ADL), whereas this function was not significantly related to age, CP equivalent doses or the presence or absence of orofacial dyskinesia among schizophrenic patients suffering from dysphagia.