Longitudinal latent growth modelling of depression in multiple sclerosis: a stable condition.
|Title||Longitudinal latent growth modelling of depression in multiple sclerosis: a stable condition.|
|Publication Type||Journal Article|
|Authors||Bamer AM, Amtmann D, Ehde DM, Johnson KL|
Background: Depression is a prevalent and disabling co-morbid condition in persons with multiple sclerosis (MS). The lifetime prevalence of a depressive disorder is more than three times that of the general population. Little is known, however, about the longitudinal course of depression in persons with MS. It is not known, for example, if depression symptoms are transient for most persons with MS or, conversely, suggestive of a persistent co-morbid condition. Objective: To model the mean trajectory of depression over time and to examine predictor variables significantly associated with the initial level of depression as well as with the slope of the trajectory of depressive symptoms. Methods: A community sample (n = 402) of individuals with MS in Washington state completed three self-report mailed surveys over the course of 30 months. Levels of depressive symptoms were assessed using the Centre for Epidemiologic Studies Depression (CES-D) scale at all three time points. The CES-D summary score collected on 3 occasions over 2.5 years was used as an outcome variable in latent growth modeling. Fourteen predictors hypothesized to affect the levels of depression were included in the model and significance was assessed using an estimate to standard error ratio of 2.0. Results: The linear model had the best model fit (CFI: 0.962; TLI: 0.887; RMSEA: 0.069). The average level of depressive symptoms at baseline was 14.72 and the trajectory slope was not statistically significant. Variables that significantly predicted the level of depressive symptoms included age, social support, fatigue, pain, and difficulties thinking. Conclusions: Results suggested that the mean level of depression did not change significantly from baseline. On average, study participants reported the same depressive symptoms over time despite that 16% of the sample reported current use of antidepressants at baseline. Further research on the natural history of depression in MS is needed. If the study results are replicated, then aggressive, multimodal treatment of depression in individuals living with MS at the time of diagnosis would be warranted.