Depressive symptoms and measures of disability: a prospective study

The purpose of this study was to test the hypothesis that decreases in severity of depressive symptoms in patients with chronic tinnitus would correlate with reductions in measures of functional disability.

This study describes the correlations between several measures of functional disability and Hamilton depression scores in two groups of patients with major depression and depressive symptoms (D-NOS) who were patients enrolled in a 12-week placebo-controlled, double-blind trial of nortriptyline. These patients had chronic severe tinnitus which was associated in most patients with high frequency hearing loss. The effect of whether affective symptoms improved and the patient's initial depression status (major depression versus depressive symptoms) are examined in order to increase understanding about the correlations between depressive symptoms and functional disability.

Most measures of functional disability decreased synchronously with Hamilton Depression Scale scores in both patients with major depression and those with subclinical depressive symptoms. Patients whose depression improved had a significantly greater change in each disability measure than patients whose depression did not improve. This significant decrease in functional disability was seen in 11 of 13 scales in the improved D-NOS group, versus only 3 of the 13 scales in the unimproved D-NOS group; 9 of 13 scales of functional disability significantly decreased in the improved major depression group, versus 3 of 13 scales in the unimproved major depression group.

The results suggest that there was a significant correlation between improvement in both major depression and depression-NOS symptoms, and decreases in measures of functional disability in an aging population with a chronic medical illness.