Data analysis
Data were entered into Statistical Package for Social Science version
22.0 (SPSS 22.0) for Windows (SPSS, Chicago, IL, USA). Both descriptive
and analytical analysis were performed on the data. Due to low clinical
importance of interactions with severity ratings of A, B, and C, only
interactions with D (major) and X (contraindicated) scales were
considered for further analysis. The interacting drugs, documentation
rate, mechanism of interaction, and clinical recommendations for
prevention were recorded. Descriptive analyses of the variables were
expressed as mean, standard deviation [SD], median, interquartile
range [IQR], and percentage as appropriate.
The association between occurrence of pDDIs and probable risk factors
were assessed using logistic regression analysis. Dependent variable was
defined as exposure to at least one major or contraindicated pDDI.
Patient’s sex, common comorbidities (hypertension, obesity, diabetes,
Ischemic Heart Disease (IHD), Chronic Respiratory Diseases (CRDs),
neoplasms), and ICU admission were taken as the covariates. At the
first, univariate logistic regression analysis was carried out.
Variables with a significant univariate p-value (<0.05) were
further assessed by multivariate analysis.