| Somnolence Syndrome is a condition of excessive drowsiness following cranial irradiation. Relationships between its incidence, severity, and time-course after radiation therapy (RT) for patients with primary or metastatic brain cancer were measured and correlated with type of treatment, tumor characteristics, and demographic characteristics (location, nature of tumor, gender, and age).; To measure somnolence and quality of life in thirty-four eligible patients, a questionnaire was employed that uses several well-validated instruments. "Acti-watches" (data loggers that record a digitally integrated value of activity) measured activity and quantified sleep patterns in twenty two subjects pursuing normal daily routines during treatment. An SAS program was used for all the analyses.; This study shows that somnolence (sleepiness), after RT, affects both perception of sleepiness (measured by the questionnaire) and sleep/activity pattern (measured objectively by the Acti-watch). The time course of somnolence shows an overall increase for the first week and an overall increase for the total duration of study. The level fluctuates with time: a decline between 8--12 weeks followed by a return of sleepiness until the end of study at about 15 weeks. Acti-watch measurements showed two changes in the sleeping pattern: (1) by changing length of night sleep; although patients were more active (restless) during their sleeping hours than before treatment, and (2) by increasing the amount of naptime during the day. In general, patients treated with whole brain RT experienced more severe somnolence than those treated with conformal RT. Averaged activity decreased to 72% of its value for whole brain and 85% for conformal RT. Four patients treated with Stereotactic RT were the least affected. The age group of 41--60 years had the highest increase in perception of sleepiness and decrease in activity. In general, women's activity was lower than the average activity level for men, and RT reduced women's activities even more. Steroids decreased the perception of sleepiness, but didn't increase activity level. Further study with more subjects will provide more detailed information. |
