After 4 weeks of treatment, patients who received omega-3 reported better sleep, depression, and mood outcomes than those who received placebo.
Estrogen-receptor inhibitors are used to treat breast cancer with positive hormone receptors in combination with other therapies. However, the drugs can lead to long-term side effects, including hot flashes, night sweats, and changes to mood and sleep.
These side effects are often treated with selective serotonin reuptake inhibitors and some anticonvulsant drugs. Omega-3 supplements contain various polyunsaturated fatty acids, which influence cell signaling and contribute to the production of bioactive fat mediators that counter inflammation. They are widely used in cardiovascular disease, breast cancer, rheumatoid arthritis, depression, and other cognitive disorders. They also appear to amplify the antitumor efficacy of tamoxifen through the inhibition of proliferative and antiapoptotic pathways that that are influenced by estrogen-receptor signaling.
“This study showed that omega-3 supplementation can improve mood and sleep disorder in women suffering from breast cancer while they (are) managing with antihormone drugs. … this supplement can be proposed for the treatment of these patients,” wrote researchers led by Azadeh Moghaddas, MD, PhD, who is an associate professor of clinical pharmacy and pharmacy practice at Isfahan (Iran) University of Medical Sciences.
The study was made available as a preprint on ResearchSquare and has not yet been peer reviewed. It included 60 patients who were screened for baseline mood disorders using the hospital anxiety and depression scale (HADS), then randomized to 2 mg omega-3 per day for 4 weeks, or placebo.
Studies have shown that omega-3 supplementation improves menopause and mood symptoms in postmenopausal women without cancer.
Omega-3 supplementation has neuroprotective effects and improved brain function and mood in rats, and a 2019 review suggested that the evidence is strong enough to warrant clinical studies.
To determine if the supplement was also safe and effective in women with breast cancer undergoing hormone therapy, the researchers analyzed data from 32 patients in the intervention group and 28 patients in the placebo group.
At 4 weeks of follow-up, patients in the intervention group had significantly lower values on the Center for Epidemiological Studies-Depression scale (mean, 22.8 vs. 30.8; P < .001), Profile of Mood State (mean, 30.8 versus 39.5; P<.001), and Pittsburgh Sleep Quality Index (mean, 4.6 vs. 5.9; P = .04). There were no statistically significant changes in these values in the placebo group.
At 4 weeks, paired samples t-test comparisons between the intervention and the placebo groups revealed lower scores in the intervention group for mean scores in the PSQI subscales subjective sleep quality (0.8 vs. 1.4; P = .002), delay in falling asleep (1.1 vs. 1.6; P = .02), and sleep disturbances (0.8 vs. 1.1; P = .005).
There were no significant adverse reactions in either group.
The study is limited by its small sample size and the short follow-up period.
The study was funded by Isfahan University of Medical Sciences. The authors declare no other conflicts of interest.