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A new clinical trial conducted by researchers in Canada has found that wearing blue-blocking glasses did not significantly reduce symptoms of mania in hospitalized patients when compared to control glasses. While the intervention was found to be safe and feasible for patients to use, the study failed to replicate earlier findings that suggested blocking blue light could be a highly effective treatment for acute mania.
These findings were published in the Journal of Affective Disorders. A companion study appearing in the International Journal of Qualitative Studies on Health and Well-being highlighted that despite the lack of clinical efficacy, patients with mania were highly willing and able to participate in rigorous research.
Bipolar disorder is a mental health condition marked by extreme shifts in mood and energy levels. One of the defining characteristics of the disorder is the presence of manic episodes. During a manic episode, an individual may experience heightened energy, racing thoughts, impulsive behavior, and a significantly decreased need for sleep. These episodes can be severe and often require hospitalization to ensure the safety of the patient and stabilization of symptoms.
Standard treatments for mania typically involve pharmaceutical interventions. Doctors often prescribe mood stabilizers and antipsychotic medications to help manage symptoms. While these medications are effective for many people, they often come with a range of side effects that can be difficult for patients to tolerate.
These side effects can include weight gain, tremors, and metabolic changes, which sometimes lead to patients stopping their medication. As a result, there is a strong interest in finding non-drug treatments that can support recovery without adding to the burden of side effects.
Scientists have recognized a strong link between bipolar disorder and the body’s internal clock, known as the circadian rhythm. Disruptions in sleep and daily rhythms are common triggers for manic episodes. Light is the primary environmental cue that regulates the human biological clock.
Specifically, short-wavelength blue light is known to signal the brain that it is daytime. When the eye detects blue light, it sends a signal to the brain to suppress the production of melatonin, a hormone that facilitates sleep.
In modern hospital environments, patients are often exposed to artificial light late into the evening. This exposure can potentially disrupt their circadian rhythms further, prolonging or intensifying manic symptoms. Previous research, including a notable case study involving total darkness therapy and a smaller clinical trial, suggested that controlling light exposure could help stabilize mood.
“Mania can be very disruptive to patients lives, often requiring hospitalization. Existing treatment for mania is medication focused and the medications available carry risk for various side-effects,” said study author Jess G. Fiedorowicz, head of the Department of Mental Health at The Ottawa Hospital.
“A treatment with lower risk of side-effects that could speed up response to treatment is highly desirable. I was inspired by a study of blue-blocking glasses for mania presented by Tone Henriksen at the International Society of Bipolar Disorders Conference in Washington, D.C. in 2017.”
However, that study had design limitations, such as the fact that the raters assessing the patients knew who was wearing the active glasses. Fiedorowicz and his colleagues sought to test the efficacy of blue-blocking glasses using a more rigorous scientific design.
The clinical trial took place at The Ottawa Hospital in Ontario, Canada. The research team recruited 42 adult participants who had been admitted to the hospital with a diagnosis of mania. To be eligible, participants had to be between the ages of 18 and 70 and willing to comply with the study procedures. The researchers utilized a randomized controlled design, which is considered the gold standard in clinical research.
Participants were randomly assigned to one of two groups. The experimental group received amber-tinted glasses designed to block approximately 99 percent of blue light. The control group received smoke-tinted glasses that blocked ultraviolet light but allowed most blue light to pass through.
To maintain a fair comparison, the researchers used a form of mild deception during the consent process. They informed participants that the study was testing two different types of light-filtering lenses, without specifying that one was a placebo. This helped ensure that the participants’ expectations did not influence the results.
The protocol required participants to wear their assigned glasses from 6:00 p.m. until 8:00 a.m. the following morning. They were instructed to wear the glasses anytime they were awake during this window. If they woke up in the middle of the night, they were asked to put the glasses on before turning on any lights.
The intervention lasted for two weeks or until the patient was discharged from the hospital. Throughout the study, all patients continued to receive their standard medical care, including any medications prescribed by their treating psychiatrists.
The primary measure of success was the change in scores on the Young Mania Rating Scale. This is a standardized tool used by clinicians to assess the severity of manic symptoms.
Crucially, the physicians who performed these assessments were blinded to the treatment assignment. They did not know which pair of glasses the patient had been wearing. This blinding prevented the raters from unintentionally biasing the scores based on their knowledge of the intervention.
The results of the quantitative study showed that participants in both groups experienced improvements in their symptoms over time. However, the researchers found no statistically significant difference between the group wearing the blue-blocking glasses and the group wearing the control glasses.
Both groups recovered at a similar rate. At the end of the two-week period, the reduction in mania scores was comparable for both the experimental and control arms of the study.
Secondary outcomes also failed to show a benefit for the blue-blocking lenses. The researchers tracked the amount of medication patients required during their hospital stay. There was no significant difference in the dosages of antipsychotics or sedatives used by the two groups.
Self-reported measures of sleep quality and mood also showed no distinct advantage for the blue-blocking intervention. The study did confirm that the blinding was successful, as neither the raters nor the participants were able to guess which group they were in better than chance.
“Circadian rhythms are very relevant to the pathophysiology of bipolar disorder and can be disrupted,” Fiedorowicz told PsyPost. “Circadian therapies therefore hold great promise but are not commonly utilized and require more study.
“Our study did not find a benefit to blue blocking glasses in patients with mania who were severely ill and being intensively treated with medications. We need more studies to understand circadian disruptions in bipolar disorder to develop better treatments. Our study was negative, but we hope that informs design of future studies of circadian treatments for bipolar disorder.”
Despite the lack of clinical benefit, the study demonstrated that the intervention was safe. The frequency of adverse events, such as headaches, was similar in both groups.
Adherence to the protocol was notably high. Most participants were able to wear the glasses for the required time, with 80 percent of the sample classified as mostly adherent. This finding challenges the common assumption that patients with acute mania are too disorganized or agitated to follow complex research protocols.
To gain a deeper understanding of the participants’ experiences, the research team conducted a separate qualitative study. This involved in-depth interviews with 24 of the patients and 10 clinical staff members. The researchers used a method called grounded theory to analyze the interview data. This approach allows themes to emerge directly from the participants’ words rather than testing a preconceived hypothesis.
The qualitative analysis revealed that patients were highly motivated to participate in the research. Three main drivers for participation emerged from the interviews. First, many participants expressed an altruistic desire to help others who might suffer from bipolar disorder in the future. Second, some viewed the study as a way to help themselves, hoping the glasses might aid their recovery. Third, the financial compensation provided for participation was a practical motivator for some.
A major theme identified in the interviews was the value of the patient-centered approach used by the research team. Participants described the study visits as a positive addition to their hospital stay. They reported that the regular check-ins with research staff made them feel heard and validated.
The process of answering questions about their mood and sleep provided them with greater insight into their own condition. Some participants noted that the research interactions felt less clinical and more personal than their standard medical interactions, creating a sense of safety and community.
The qualitative study also explored the feasibility of the intervention from the patients’ perspective. Most participants found the glasses acceptable and easy to use. They appreciated having a choice of frame styles. Challenges were minor and included physical discomfort from wearing glasses over prescription lenses or difficulties remembering to put them on immediately upon waking at night. However, patients generally felt capable of adhering to the rules, even while experiencing symptoms of mania.
Clinicians interviewed for the study also expressed support for the research. Psychiatrists and nurses viewed the blue-blocking glasses as a low-risk intervention that complemented their clinical care. They did not find that the study disrupted the workflow on the inpatient units.
Clinicians noted that the study provided patients with additional structure and resources, which was seen as a benefit regardless of the intervention’s efficacy. The staff also reported that introducing the research opportunity helped build rapport with their patients.
The study has some limitations. The sample size, while larger than previous trials, was still relatively small. This limits the statistical power to detect small differences between groups.
Additionally, the study was conducted in a hospital setting where patients have limited exposure to natural outdoor light. This environment might dampen the potential contrast between blocking and receiving blue light. The researchers also acknowledged that while they attempted to measure sleep using actigraphy watches, this data was only available for a subset of participants.
Future research directions were suggested by the findings. While blue-blocking glasses may not be sufficient as a standalone or additive treatment for acute mania in patients already on heavy medication, they might still have a role in other contexts.
The researchers suggest exploring the use of these glasses for the prevention of manic episodes in people showing early warning signs. Investigating their use in outpatient settings, where light exposure is more variable, could also yield different results.
The qualitative findings provide evidence that people with acute mania are capable partners in scientific research. The authors argue that illness severity should not automatically exclude patients from participating in clinical trials. The study showed that with appropriate support and accommodations, such as repeated explanations and patience during the consent process, vulnerable patients can provide informed consent and adhere to study protocols.
“There was a lot of interest in blue blocking glasses in participants,” Fiedorowicz said. “There is great interest in non-medication treatments for bipolar disorder for sure and circadian therapies in particular are appealing to individuals.”
“On rare occasion, I’ve encountered naysayers who suggest that people when manic can’t do studies like this. Our qualitative and quantitative data strongly rebuts this misguided assertion. Studying people with mania is, of course, not without its challenges, but it can be done with the right supports and team in place and providing participants accomodations and flexibility.”
The study, “The Ottawa sunglasses at night study: A randomized controlled trial of blue-blocking glasses for mania,” was authored by Jess G. Fiedorowicz, Eric Mikhail, Marco Solmi, Joseph K. Burns, Jessica Yu, Sara Siddiqi, Thanh Nguyen, Andrew L. Smith, and Rébecca Robillard.
The study, “The feasibility of conducting non-pharmacological research studies in participants with mania: a grounded theory qualitative analysis of the Ottawa Sunglasses at Night study,” was authored by Jessica Yu, Joseph K. Burns, Eric Mikhail, Marco Solmi, Simon Hatcher, Andrew L. Smith, Rébecca Robillard, Thanh Nguyen, Nicole Edgar, Tetyana Kendzerska, Mark Kaluzienski, Andrea Bardell, and Jess G. Fiedorowicz.
