Could melatonin have a potential adjuvant role in the treatment of the lasting anosmia associated with COVID-19? A review.

INTRODUCTION: Anosmia, the loss of the sense of smell, is usually associated with rhinopathies and has been reported as a common symptom of COVID-19. There is no specific drug to treat this condition, although some evidence suggests that melatonin could promote the recovery of olfactory sensory neurons. METHODS: We set out to perform a narrative review to synthesize the current evidence in this area in respect of our hypothesis that melatonin may be linked with anosmia and play a part in oxidative stress and the regulation of inflammation. The main electronic databases (MEDLINE/PubMed, Embase, and Cochrane) were searched. RESULTS: The search produced 26 articles related to our hypothesis. Some studies examined issues related to melatonin's effects and its use as adjuvant therapy for COVID-19. Despite some studies suggesting that melatonin may have potential in the treatment of COVID-19, to the best of our knowledge, there have been no trials that have used it to treat anosmia associated with the disease. Few articles identified proposed that melatonin might have an effect on olfactory cells. DISCUSSION: Further experimental and clinical research on the role of circadian melatonin in the olfactory system is warranted. This will provide evidence of the use of melatonin in the management of anosmia. A number of identified studies suggest that the imbalanced release of melatonin by the pineal gland associated with sleep disturbance may play a role in anosmia, although the specific pathway is not yet entirely clear. This may be a base for further research into the potential role of melatonin as adjuvant treatment of anosmia.

Characteristics Associated With People With Chronic Low Back Pain Meeting Physical Activity Guidelines and Recommendations for Sedentary Behavior: A Cross-Sectional Study.

OBJECTIVE: The purpose of this study was to identify factors associated with meeting physical activity guidelines and sedentary recommendations in people with chronic low back pain (LBP). METHODS: This was a cross-sectional study including 171 people with chronic LBP. Trained assessors collected information regarding demographic, anthropometric, and clinical data. Physical activity levels and sedentary time were objectively measured using a tri-axial accelerometer. Participants were classified as being physically active (ie, performing at least 150 minutes of moderate or 75 minutes of vigorous physical activity per week) and sedentary (ie, more than 8 hours of time spent in sedentary activities per day). Multivariable logistic regression analyses were used to determine the association of being physically active or sedentary with the range of demographic, anthropometric and clinical variables. RESULTS: Our results showed that although lower body mass index (odds ratio [OR] = 0.91; 95% CI: 0.85-0.98) and higher self-reported levels of leisure time physical activity (OR = 3.46; 95% CI: 1.94-6.15) were associated with being physically active, lower self-reported levels of physical activity at work (OR = 0.56; 95% CI: 0.39-0.81) was associated with being sedentary. CONCLUSION: Our findings showed that, in people with LBP, lower body mass index and higher levels of leisure time physical activity may be important factors for identifying those physically active. In contrast, lower levels of physical activity at work may be considered when identifying sedentary people with LBP. Future studies should consider these factors when designing interventions aiming to promote physical activity and decrease sedentary behavior in this population.

Physical Activity-Based Interventions Using Electronic Feedback May Be Ineffective in Reducing Pain and Disability in Patients With Chronic Musculoskeletal Pain: A Systematic Review With Meta-Analysis.

OBJECTIVE: To investigate the effectiveness of physical activity-based interventions using electronic feedback in reducing pain and disability compared to minimal or no interventions in patients with chronic musculoskeletal pain. DATA SOURCES: The following electronic databases were searched: EMBASE, MEDLINE, Cochrane Central Register of Controlled Trials, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, SPORTDiscus, Web of Science, Physiotherapy Evidence Database, and main clinical trial registers. STUDY SELECTION: Randomized controlled trials investigating the effect of physical activity interventions using electronic feedback (eg, physical activity monitors) on pain and disability compared to minimal or no interventions in adults with chronic musculoskeletal pain were considered eligible. DATA EXTRACTION: Pooled effects were calculated using the standardized mean difference (SMD), and the Grading of Recommendations Assessment, Development and Evaluation system was used to assess the overall quality of the evidence. DATA SYNTHESIS: Four published randomized controlled trials and 4 registered unpublished randomized controlled trials were included. At short-term follow-up, pooled estimations showed no significant differences in pain (2 trials: n=116; SMD=-.50; 95% confidence interval, -1.91 to 0.91) and disability (2 trials: n=116; SMD=-.81; 95% confidence interval, -2.34 to 0.73) between physical activity-based interventions and minimal interventions. Similarly, nonsignificant results were found at intermediate-term follow-up. According to Grading of Recommendations Assessment, Development and Evaluation, the overall quality of the evidence was considered to be of low quality. CONCLUSIONS: Our findings suggest that physical activity-based interventions using electronic feedback may be ineffective in reducing pain and disability compared to minimal interventions in patients with chronic musculoskeletal pain. Clinicians should be cautious when implementing this intervention in patients with chronic musculoskeletal pain.