Trajectories and predictors of symptom occurrence, severity, and distress in prostate cancer patients undergoing radiation therapy

Abstract

Context: Radiation therapy (RT) is a common treatment for prostate cancer. Despite available research, prostate cancer patients report that information about side effects is their most important unmet need. Additional research is needed that focuses on specific dimensions of the patient's symptom experience.

Objectives: The study's purposes were to evaluate the trajectories of occurrence, severity, and distress of the six most prevalent symptoms reported by patients undergoing RT for prostate cancer and the effects of selected demographic and clinical characteristics on these trajectories.

Methods: Patients completed the Memorial Symptom Assessment Scale 11 times before, during, and after RT. For problems with urination, pain, lack of energy, feeling drowsy, difficulty sleeping, and diarrhea, the trajectories of occurrence, severity, and distress were evaluated using multilevel generalized linear models.

Results: Across all three dimensions, pain, lack of energy, feeling drowsy, and difficulty sleeping followed a decreasing linear trend. Problems with urination and diarrhea demonstrated more complex patterns of change over time.

Conclusion: Although longitudinal data on pain, lack of energy, feeling drowsy, and difficulty sleeping are limited, they are highly prevalent symptoms in these patients. In addition, diarrhea becomes a significant problem for these patients over the course of RT. A number of demographic and clinical characteristics affect the trajectories of these common symptoms differentially.

Fig. 1

Observed (open circles) and predicted (filled circles) trajectories for the probability of occurrence of problems with urination (A), pain (B), lack of energy (C), feeling drowsy (D), difficulty sleeping (E), and diarrhea (F) across the 25 weeks of the study.

Fig. 2

Observed (open circles) and predicted (filled circles) trajectories for the probability of occurrence of problems with urination, across the 25 weeks of the study, in whites (A) compared to non-whites (B) and in patients who did (D) and did not (C) report pain at the initiation of radiation therapy.

Fig. 3

Observed (open symbols) and predicted (filled symbols) trajectories for the probability of severity ratings for problems with urination (A), pain (B), lack of energy (C), feeling drowsy (D), difficulty sleeping (E), and diarrhea (F) across the 25 weeks of the study. Severity ratings are plotted as none vs. slight to very severe and none/slight vs. moderate to very severe.

Fig. 4

Observed (open symbols) and predicted (filled symbols) trajectories for the probability of severity ratings for problems with urination, across the 25 weeks of the study, in patients who did (B) and did not (A) report pain at the initiation of radiation therapy. Severity ratings are plotted as none vs. slight to very severe and none/slight vs. moderate to very severe.

Fig. 5

Observed (open symbols) and predicted (filled symbols) trajectories for the probability of distress ratings for problems with urination (A), pain (B), lack of energy (C), feeling drowsy (D), difficulty sleeping (E), and diarrhea (F) across the 25 weeks of the study. Distress ratings are plotted as did not have vs. not at all to very severe, did not have/not at all vs. mild to very severe, did not have to mild vs. moderate to very severe, and did not have to moderate vs. severe/very severe.

Fig. 6

Observed (open symbols) and predicted (filled symbols) trajectories for the probability of distress ratings for problems with urination, across the 25 weeks of the study, in patients who did (B) and did not (A) report pain at the initiation of radiation therapy. Distress ratings are plotted as did not have vs. not at all to very severe, did not have/not at all vs. mild to very severe, did not have to mild vs. moderate to very severe, and did not have to moderate vs. severe/very severe.

Fig. 7

Observed (open circles) and predicted (filled circles) trajectories for the probability of occurrence of lack of energy, across the 25 weeks of the study, in patients who were (B) and were not (A) on hormonal therapy and in patients who did (D) and did not (C) report pain at the initiation of radiation therapy.

Fig. 8

Observed (open symbols) and predicted (filled symbols) trajectories for the probability of severity ratings for lack of energy, across the 25 weeks of the study, in patients who did (B) and did not (A) report pain at the initiation of radiation therapy. Severity ratings are plotted as none vs. slight to very severe and none/slight vs. moderate to very severe.

Fig. 9

Observed (open symbols) and predicted (filled symbols) trajectories for the probability of distress ratings for lack of energy, across the 25 weeks of the study, in patients who were (B) and were not (A) on hormonal therapy and in patients who did (D) and did not (C) report pain at the initiation of radiation therapy. Distress ratings are plotted as did not have vs. not at all to very severe, did not have/not at all vs. mild to very severe, did not have to mild vs. moderate to very severe, and did not have to moderate vs. severe/very severe.