Effects of a dawn-dusk simulation on circadian rest-activity cycles, sleep, mood and well-being in dementia patients

Light is the most powerful "zeitgeber" signal to synchronize circadian sleep-wake cycles. In dementia, these rhythms are often fragmented - probably due to loss of neuronal function of the suprachiasmatic nuclei (the biological "master clock" in the brain) and/or weakness of external zeitgebers. We investigated the effects of a prototype dawn-dusk simulator (DDS) on circadian rest-activity cycles, sleep, mood and well-being in a balanced crossover design during fall and winter in 20 institutionalized patients with dementia (86 ± 6 y, 17 f). All participants had one baseline week followed by exposure to individually timed DDS over their beds for 7-8 weeks. They spent 8 weeks without DDS as a control. Mood, self-reliant daily activity, social behavior, agitation, and quality of life were assessed by standardized questionnaires and visual analogue scales, regularly rated by trained caregivers. Circadian and sleep characteristics of their rest-activity cycles were analyzed by actimetry over 17 weeks. DDS exposure led to significantly better mood in the morning hours after waking. The effects were most pronounced in the second 4 weeks with DDS, indicating that positive effects emerged gradually. Differences in circadian rest-activity cycles and sleep were mainly age-dependent. We found statistically significant correlations between measures of higher quality of life and better mood, greater alertness and circadian rhythm stability. We conclude that continuous, long-term application of dawn-dusk simulation at the sleep-wake transitions appears to increase external zeitgeber strength in institutionalized patients with dementia. The DDS may provide an effective, non-invasive tool to improve mood and ameliorate patients' quality of life.

Prognostic impact of additional extended surgical procedures in advanced-stage primary ovarian cancer

BACKGROUND

Treatment of advanced-stage ovarian carcinoma includes radical cytoreductive surgery, which aims at removing all visible tumor tissue followed by platinum and paclitaxel chemotherapy. Complete tumor resection may require extended surgical procedures. This paper reports on the prognostic impact of extensive surgery and surgical morbidity in patients with advanced-stage ovarian carcinoma.

METHODS

Patients with ovarian carcinoma [Fédération Internationale de Gynécologie et d'Obstétrique (FIGO) stage IIIB-IV] undergoing primary surgery in our tertiary gynecologic oncology unit between 1997 and 2007 were eligible for this study. The impact of established prognostic factors and the interaction with extent of surgical procedures on survival were assessed.

RESULTS

A total of 267 patients aged between 29 and 88 years (median 64 years) were eligible for this study. Overall survival time was improved in patients who underwent complete tumor resection [hazard ratio (HR) 3.61 (1.91-6.61), P < 0.001]. No significant survival difference was observed between completely operated patients in whom extended or standard surgical procedures were applied [HR 1.37 (0.70-2.69), P = 0.358], and severe surgical complications were found to be equally distributed between the two patient groups.

CONCLUSIONS

Our results may encourage the application of extended surgical procedures in patients who would otherwise be rendered incompletely debulked after primary cytoreduction. We could demonstrate an impact of complete tumor resection on patient prognosis and this was not traded off for extensive additional surgical morbidity.