Factors associated with severity of depression in multiple sclerosis

Abstract

Numerous studies have shown an increased rate of suicide in patients with multiple sclerosis. In addition, research has found an increased rate of lifetime suicidal intent. The present study examined the prevalence of suicidal ideations in a sample of MS patients, as well as the variables associated with severity of depression.;Two hundred thirty-four patients recruited from a tertiary care center for multiple sclerosis completed a Beck Depression Inventory (BDI) and consent form allowing access to review his or her chart. The information obtained from the chart included: demographic variables (age, gender, marital status, and race), antidepressant use, and physician-determined level of disability. Race could not be examined as a variable because the sample was not diverse enough to evaluate differences.;A principal component analysis (PCA) found that depression scale responses in the current sample are made up of five factors: negative ideations, overall energy, severity of depression, akithesia, and anhedonia. These five factors were loaded on by all 21 BDI items, accounting for 64.6 percent of the variance. The factor "severity of depression" was used as an outcome measure in a logistic regression model. Anhedonia was the only factor from the PCA predictive of severity of depression.;Age but not gender was found to be correlated with severity of depression. Antidepressant use was associated with severity of depression. Level of disability was not found to be significantly associated with severity of depression, but there was a trend towards significance. More specifically, younger patients who are not currently using antidepressants and who have anhedonia are more likely to have a high severity of depression.;The logistic regression was able to correctly classify 94 percent of patients who were not severely depressed and correctly classify 52.2 percent of people who scored high on the severity of depression dimension.;A receiver-operated characteristic curve (ROC) analysis found a sensitivity of 84 percent and a specificity of 70 percent. In other words, the three items that make up the anhedonia factor identified 84 percent of patients who were severely depressed and identified 70 percent of patients who were not severely depressed. The overall accuracy of the test was 82 percent.;In conclusion, the study demonstrated that younger multiple sclerosis patients who were not currently taking antidepressants and who had anhedonia were more likely to have severe depression. The study also showed that the three anhedonia items from the BDI can serve as a quick screening method to determine severity of depression. Future research is indicated in the study of severity of depression in patients with multiple sclerosis in order to examine additional screening methods and treatment options.