Promoting Sleep in Mothers of Low Birth Weight Infants: A Pilot Study

Introduction: Mothers with low birth weight (LBW) infants being hospitalized in the intensive care unite (ICU) are at a higher risk of impaired sleep due to extended periods of exposure to the artificial dim light in the ICU and stress related to the infant’s medical condition. Impaired sleep may have negative impact to mother’s well-being. The purpose for this pilot feasibility study is to determine the effects of a sleep hygiene intervention plus bright light treatment, compared to usual care with attention control, on health outcomes for mothers of LBW infants hospitalized in the ICU.
 
Methods: Subjects included 17 first-time mothers who had an LBW infant hospitalized in ICU.  The mothers completed two sets of data in before and after the 4-week intervention: 1) Perceive Stress Scale (PSS), Impact of Event Scale (IES), General Sleep Disturbance Scale (GSDS), Numerical Rating Scale for Fatigue, Edinburgh Postnatal Depression Scale (EPDS), Medical Outcomes Short Form-36version 2 (SF36v2), and 2) total sleep time (TST) averaged from two nights of wrist actigraphy monitoring. The treatment group mothers received a 12,000 lux blue-green bright therapy (BL; n=9) for 4 weeks and the control group mothers received a placebo dim red light therapy (RL; n=8).    

Results: The baseline measurements showed the average TST was 400 minutes (SE= 22.3), which was significantly less than the mothers who reported needing to feel refreshed (p= .005). The GSDS mean score was 2.8 (SD=0.8), indicating those mothers were poor sleepers. The fatigue mean scores were 3.9 and 5.3 for morning and evening respectively, indicating a moderate fatigue severity for mothers. The EPDS mean score was 14.6 (SD=5.9), indicating that the mothers experienced depressive symptoms. The mean scores for the IES and PSS were 35.8 (SD= 12.9) and 21.1 (SD= 5.9) respectively, indicating the mothers perceived moderate stress levels from their infant’s hospitalization, and their stress level was higher than the norm female adults. The mother’s physical and mental health were measured by the SF36v2, resulting about 1 SD below the mean scores compared to the age-matched U.S. general female population. 

Post treatment, the average nocturnal TST increased from 383 minutes (SE= 34) at the baseline to 424 minutes (SE= 13) for the BL group. However, the TST in the RL group mothers worsened from 413 minutes (SE= 38) to 373 minutes (SE=20). After 4-week intervention, the BL group mothers’ daytime TST decreased from 114 to 39 minutes; the means scores of GSDS, EPDS, and IES were less (p< .05); the aggregated physical health components from SF36v2 improved from -1.09 to .006 SD (p= .025).      

Conclusions: Results indicate that bright light therapy may improve a mother’s nocturnal sleep, decrease daytime sleepiness, and be beneficiate to her well-being.  A larger scale of clinical trials is needed to further examine the effects of bright light therapy.