Study data published in the Journal of Sleep Research describes the relationship between sleep disorders, physical activity, and pain in patients with fibromyalgia. In a cohort of patients with fibromyalgia and insomnia, afternoon and early evening physical activity was associated with increased insomnia. The relationship between physical activity and sleep patterns was particularly pronounced in those with greater self-reported pain.
The researchers extracted data from the baseline assessment of a clinical research study evaluating insomnia in fibromyalgia. The study recruited adults with fibromyalgia from participating rheumatology and sleep clinics in Florida. Participants had insomnia if they reported a latency period of> 30 minutes (SOL) or a wake time after the onset of sleep (WASO) of ≥3 days / week for a duration of> 6 months. Eligible participants also reported dysfunction during the day due to insomnia.
In the basic assessment, physical activity and sleep patterns were recorded using actigraphy. Patients wore Actiwatch-2 watches configured to measure activity and photopic light for 14 consecutive days. Physical activity was reported as the average activity per minute at three different time intervals: afternoon (12:00 p.m. – 3:00 p.m.), early evening (3:00 p.m. – 6:00 p.m.) and late evening (6:00 a.m. – 9:00 a.m.) Clock). 00 o’clock).
Patients were asked to rate their pain for each of the 14 days on a scale from 0 (no pain) to 100 (most intense pain). The use of medication for pain or sleep was also recorded daily. Multiple regression was performed to assess the relationship between physical activity, insomnia and pain.
The analytical cohort consisted of 160 participants, including 150 (94%) women. The mean age was 52.44 ± 11.73 years. In regression models, self-reported pain alone was not significantly associated with sleep outcomes. Instead, more afternoon physical activity (12:00 p.m.-3:00 p.m.) was associated with lower sleep efficiency, lower total sleep time, and higher WASO (all P <0.001). It was found that pain level mediates these relationships as the association between sleep efficiency and physical activity increased with greater pain. However, sleep efficiency was strongly related to afternoon physical activity for all pain levels (all P <0.001).
Greater activity in the early evening (3:00 p.m. to 6:00 p.m.) was also independently associated with lower sleep efficiency, lower total sleep time, and higher WASO (all P <0.001). As with the afternoon model, early evening activity was a stronger predictor of low sleep efficiency in subjects with high pain (P <0.001). Physical activity remained associated with sleep efficiency in patients with average pain (P <0.001). However, in patients with mild pain, sleep efficiency was not significantly related to early evening physical activity (P = 0.06). Models that rated activity in the late evening (6:00 p.m.- 9:00 a.m.) did not identify any significant associations with sleep results.
The results of this study suggest that afternoon and early evening physical activity can cause insomnia in patients with fibromyalgia and insomnia. This relationship was most pronounced in those with severe pain. Late evening activities did not seem to affect sleep.
Limitations of the study include the small cohort size and the lack of information on drug use and activity type.
“Prospective studies are needed to … explore causal pathways between objective activity before bed, pain, drug use, and sleep outcomes in fibromyalgia,” the researchers wrote. “In particular, studies examining whether increased physical activity in the afternoon and early evening aggravates pain or, in fibromyalgia, causes hyperarousalism before bedtime are warranted.”
McGovney KD, Curtis AF, McCrae CS. Relationship between objective afternoon and evening physical activity and objective sleep in patients with fibromyalgia and insomnia [published online October 29, 2020]. J Sleep Res.doi: 10.1111 / jsr.13220
This article originally appeared on Psychiatry Advisor