Depression and anxiety at 1- and 12-months post ischemic stroke: methods for examining individual change over time.

Background Depression is commonly studied post stroke, while anxiety is less studied. This study presents prevalence of depression and anxiety at 1- and 12-months post ischemic stroke alongside three methods for examining within-subjects change over time. Methods Participants were ischemic stroke patients of the Auckland Regional Community Stroke Study (ARCOS-V) with Hospital Anxiety and Depression Scale data at 1- (n =343) and 12-months (n =307). Change over time was examined using within-subjects repeated measures ANOVA, calculation of the Reliable Change Index, and a Sankey diagram of those meeting cut-off scores (>7) for caseness over time. Results Using repeated measures ANOVA, depression scores didn't change significantly over time, while anxiety symptoms decreased significantly. When reliable change was calculated, 4.2% of individuals had reliable decreases in anxiety symptoms, while 5.7% had reliable decreases in depression symptoms. Those who had a reliable decrease in one tended to have a reliable decrease in the other. In the Sankey, the proportion of those meeting the cut-off score for anxiety did not change over time (12.8 and 12.7% at 1- and 12-months), while those meeting the cut-off for depression increased slightly (3.7-4.5%) and those meeting cut-offs for both decreased from 10.4 to 8.1%. Conclusion The three methods produced very different findings. Use of cut-off scores is common but has limitations. Calculation of clinically reliable change is recommended. Further work is needed to ensure depression and anxiety are monitored over time post-stroke, and both should be the subject of intervention efforts in both acute and late stages post-stroke.