Longitudinal follow-up study using the distress and impact thermometer in an outpatient chemotherapy setting

Although the combined use of the Impact Thermometer (IT) with the Distress Thermometer (DT), DIT, is reported to be a validated screening tool for clinically significant psychological distress in cancer patients, its longitudinal changes in the outpatient chemotherapy setting have not been examined.

The objective was to clarify the longitudinal changes in distress evaluated by the DIT and effects of coexisting physical symptoms in an outpatient chemotherapy setting.

A total of 297 patients who underwent chemotherapy for any malignancy on an outpatient basis were included. All the participants completed a questionnaire that included the DIT and intensities of seven physical symptoms (pain, somnolence, fatigue, dyspnea, appetite loss, abdominal distention, and nausea) at the initial and follow-up visit.

Although 109 patients had moderate or severe distress (the DT ≥4 and IT ≥3) at the initial visit, 46.8% of these patients improved their distress (DIT score below the cutoff of moderate distress) at their follow-up visit. Also, 85 patients had severe distress (DT ≥5 and IT ≥4) at the initial visit, and 43.5% of these patients improved their distress (DIT score below the cutoff of severe distress) at their follow-up visit. In a subgroup of patients who had no severe physical symptoms at the initial visit, 69.0% and 68.4% of the patients with moderate or severe distress and severe distress at the initial visit, respectively, improved their distress (DIT scores below the cutoff of moderate and severe distress) at the follow-up visit.

The distress evaluated by DIT can change on sequential measurements within short time intervals. Further study is needed to determine the appropriate use of the DIT for the screening and monitoring of psychological distress in an outpatient chemotherapy setting.