Bipolar Research: Autoimmune Diseases, Hep C, Diabetes, and More

Studies on autoimmune diseases, hepatitis C, and diabetes show just how connected bipolar disorder is to whole-body health — and point to treatments and habits that could help.

Living with bipolar disorder means your mental health is connected to your whole body’s health. Now, new research is uncovering important links between bipolar disorder and physical health conditions, including autoimmune diseases, hepatitis C, and type 2 diabetes. The good news? Recent studies also suggest that simple changes — like getting more exercise or bright light — can help reduce symptoms. Here’s what these findings mean for you and your health. 

Study Links Bipolar Disorder and Autoimmune Diseases

Chronic inflammation is a story of too much of a good thing. 

When you experience illness or injury, short-term inflammation helps you heal, according to StatPearls. But when inflammation lingers for months or years, it does the opposite, harming the body. A review of the research suggests that this type of chronic inflammation may contribute to a host of psychiatric conditions, including bipolar disorder. 

Could this mean that if you have chronic inflammation from an autoimmune condition, you’re more likely to have bipolar disorder than someone without it? New research published in BMJ Mental Health suggests the answer is yes. 

What the Research Says

Evidence suggests that chronic inflammation and mental health conditions go hand in hand. For instance, substances in your blood related to inflammation tend to be higher when you have bipolar disorder, according to a review of 53 studies. 

But most of the research so far has looked at smaller groups of people, since it’s costly and time-consuming to process blood samples and analyze biomarkers. To say whether the connection between inflammation and psychiatric diagnoses is solid, you’d need to look at large numbers of people — including people who do and don’t have these conditions.

Researchers in Scotland realized they had a huge opportunity thanks to a new U.K.-based project called Our Future Health, whose goal is to enroll millions of participants who agree to share their health information to benefit research. 

Already, more than 1.5 million people have joined. And, in addition to other health data, they have provided key information related to mental health and inflammation. Volunteers shared surveys on mental health symptoms, whether they had an affective disorder (bipolar disorder, major depressive disorder, or an anxiety disorder), and whether they had an autoimmune condition (rheumatoid arthritis, Graves’ syndrome, inflammatory bowel disease, lupus, multiple sclerosis, or psoriasis). The researchers were especially interested in that last bit of data, since autoimmune conditions cause chronic inflammation, making their presence a good substitute for inflammatory blood markers. 

When the researchers analyzed the data, here’s what they found: 

• Overall, having an autoimmune condition was linked with a higher risk of mood or anxiety disorders. About 28.8 percent of people with an autoimmune condition also experienced bipolar disorder, depression, or anxiety at some point in their lives — compared with 17.9 percent of those without an autoimmune condition.
• When it came to bipolar disorder specifically, the odds were higher in people with autoimmune conditions, though it remained relatively rare. In the study, 0.9 percent of people with an autoimmune condition also had bipolar disorder, versus 0.5 percent without — nearly doubling the risk.
• The link between autoimmune conditions and mood or anxiety disorders was stronger in women than in men. Among women with an autoimmune condition, 31.6 percent had experienced a mood or anxiety disorder at some point, and 1 percent had been diagnosed with bipolar disorder specifically.

Why It Matters

This study slots into what’s become clear in recent years: Bipolar disorder is a brain-based health condition that affects your whole body. The findings suggest that the inflammation that characterizes autoimmune conditions may play an important role in how bipolar disorder works, which could lead to new ways to treat it.

What This Means for You

• If you live with an autoimmune condition, make sure your mental health is being monitored, too. Research shows that people with certain autoimmune diseases, like rheumatoid arthritis or inflammatory bowel disease, are at greater risk for mood and anxiety disorders, including bipolar disorder. This is especially true for women. Regular mental health screenings can help catch symptoms early, making treatment more effective and preventing the pain of delayed care.
• Make fighting chronic inflammation a habit. Unlike acute inflammation, chronic inflammation isn’t good for you. Some risk factors for chronic inflammation are out of your control, but healthy habits can make a difference. Cleveland Clinic recommends reducing chronic inflammation through regular physical activity, eating minimally processed and anti-inflammatory foods, avoiding smoking, and limiting alcohol.

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Could Antivirals Help Treat Bipolar Disorder? 

Hepatitis C (HCV) is a blood-borne virus that’s most well-known for damaging the liver. But new research published in Translational Psychiatry suggests something surprising: HCV can make its way into a crucial part of the blood-brain barrier, where experts now think it could play a role in triggering some cases of bipolar disorder.

What the Research Says

When you look at large groups of people, you can see that rates of developing bipolar disorder, schizophrenia, and major depressive disorder all increase when viral infections increase. This has led some experts to wonder about the role particular viruses play in certain psychiatric conditions. 

HCV is one such virus. HCV is a virus you can get from infected blood that affects the liver, according to Cleveland Clinic. Other studies have suggested that HCV may be more common in people with bipolar disorder and schizophrenia. This makes some sense since people with the virus experience problems with thinking and mood.

But when scientists have tried looking for signs of HCV infections in individuals with these mental health conditions, they’ve come up short. 

Until now. 

A Baltimore-based research group, including scientists from Johns Hopkins University and Stanley Medical Research Institute, a nonprofit focused on bipolar and schizophrenia research, wondered if other scientists just hadn’t looked in the right place yet. 

They decided to examine tissue not from the brain itself, but from the choroid plexus, an important part of the brain lining that helps form the blood-brain barrier, according to StatPearls. 

After examining postmortem samples of the choroid plexus from more than 250 people, the researchers discovered that tissue from people with bipolar disorder and schizophrenia was more likely to have evidence of HCV than individuals with major depressive disorder or those with no history of any mental health conditions. Interestingly, people who had known chronic hepatitis C but didn’t have bipolar disorder or schizophrenia didn’t have the virus in their brain lining.

The results were intriguing, but the research team needed to be sure they weren’t a fluke. There could be something systematically different about the kind of people who decide to donate their brains to science that could mean the findings don’t translate to the average person with bipolar disorder or schizophrenia. 

Since examining brain lining in large numbers of people isn’t practical, they decided to use the next best thing: electronic health records. 

While your health records wouldn’t say if HCV is in your choroid plexus, they would say if you had been diagnosed with chronic viral hepatitis C. Since most people with HCV don’t have symptoms, the number with chronic hepatitis C will be lower than the number who have the virus in their choroid plexus. Still, if HCV has something to do with bipolar disorder and schizophrenia, you’d expect more people with those conditions to be diagnosed with chronic hepatitis C. 

After reviewing about 285 million people’s records, the research team found that, compared with people without a mental health condition, having chronic hepatitis C is about 8 times more common in people who also have bipolar disorder and 7.5 times more widespread in people who have schizophrenia. The overall rates of diagnosed chronic hepatitis C are still small overall:

• 3.91 percent of people with bipolar disorder
• 3.59 percent of people with schizophrenia
• 1.79 percent of people with major depressive disorder
• 0.48 percent of people without any psychiatric diagnosis

Why It Matters

This study provides some of the first direct evidence that a virus (HCV) is more common in people with bipolar disorder and schizophrenia, suggesting it may be involved in these conditions and pointing to new possibilities in bipolar prevention and treatment. 

The fact that HCV was found in the brain lining and outside of the brain itself is also important. Looking for evidence of viruses in other parts of the central nervous system is a new strategy that could inspire other scientists, leading to new breakthroughs in understanding the possible role of viruses in bipolar disorder.

Key Highlights

• Hepatitis C may contribute to bipolar disorder in some people. Bipolar disorder doesn’t have a single cause. Other research shows that genetics, life experiences, and other factors all play a role. This study sits alongside those findings, suggesting that viral infections could be another piece of the puzzle for some people. But even in this study, not everyone with bipolar disorder had HCV in their brain lining, so it’s not a universal cause. Bipolar disorder likely has many different contributing factors, and HCV might be one of them.
• Preventing hepatitis C might help prevent bipolar disorder. According to the American Liver Foundation, around 17,000 new people are infected with HCV every year. If a portion goes on to develop bipolar disorder as a result, preventing HCV could potentially eliminate thousands of new cases of bipolar disorder annually. You can help protect yourself from HCV by refraining from illegal drug use, making sure sterile needles are used when you get tattoos and body piercings, and practicing safer sex, according to Mayo Clinic.
• Antivirals could open new doors for bipolar disorder treatment. Here’s the good news: HCV is very treatable. A simple two- to three-month course of oral medication cures HCV in 95 percent of cases, according to data from the Centers for Disease Control and Prevention (CDC). If future research confirms that HCV has a part in some people’s bipolar disorder, antiviral treatment might help bring more stability to their lives.

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New Study: Having Bipolar Disorder Increases Your Risk of Diabetes Emergencies

Bipolar disorder can come with unwanted companions. One of those is type 2 diabetes. 

Not only are you more likely to get diabetes if you have bipolar disorder, but if you do get diabetes, you face a higher risk of serious diabetes-related problems, like heart disease, down the road. 

But what about in the short run? Does having bipolar disorder make it more likely you’ll have acute complications like dangerously high blood sugar? New research published in the journal Scientific Reports reveals answers you need to know if you live with both conditions. 

What the Research Says

Researchers in Taiwan set out to understand: If you have both bipolar disorder and type 2 diabetes, are you more likely to end up in the emergency room with dangerously high blood sugar? 

To figure this out, they looked at nine years of health records from an American research database. They found about 40,000 people who were newly diagnosed with and treated for type 2 diabetes and had previously been diagnosed with bipolar disorder. Next, they created a comparison group. It had exactly the same number of people recently diagnosed with diabetes. The second group was similar in nearly every way except for one thing: They didn’t have bipolar disorder. 

Next, the researchers looked at rates of blood sugar emergencies (called hyperglycemic crises) in each group. The two main kinds are diabetic ketoacidosis and hyperosmolar hyperglycemia: 

• Diabetic Ketoacidosis This happens when your body doesn’t make enough insulin, so it starts breaking down fat for energy. The process makes acids called ketones. A modest level of ketones isn’t a problem and can even be therapeutic in the case of ketogenic therapy. But in diabetic ketoacidosis, your ketone level is so high that your blood becomes dangerously acidic. 
• Hyperosmolar Hyperglycemia This is when your blood sugar has been high for so long that your body becomes severely dehydrated. It is rarer and more deadly than diabetic ketoacidosis.

If having bipolar disorder makes you more at risk for hyperglycemic crises, people in the bipolar disorder group would have more episodes of diabetic ketoacidosis and hyperosmolar hyperglycemia in their medical records — and that’s just what the researchers found. Compared with people without bipolar disorder, people with the condition had:

• 12 percent higher risk of diabetic ketoacidosis 
• 20 percent higher risk of hyperosmolar hyperglycemia

When looking at the overall risk of experiencing either condition (or both), people with bipolar disorder had a 13 percent higher risk than those without bipolar.

This number (13 percent) falls between the two individual risks because it counts each person only once, even if they experienced both conditions. Since diabetic ketoacidosis is more common than hyperosmolar hyperglycemia, the combined risk is pulled closer to the diabetic ketoacidosis risk of 12 percent.

Why It Matters

While the fact that having bipolar disorder seems to make you more vulnerable to hyperglycemic crises isn’t exactly good news, knowing about this risk certainly is. When you’re armed with information about what to look out for, you can take extra steps to protect your health. 

What This Means for You

• Your blood sugar may be more difficult to control if you have bipolar and type 2 diabetes. According to Cleveland Clinic, hyperglycemia can be impossible to avoid completely, but you can take action to limit the possibility, including: taking your bipolar and diabetes medications as prescribed, focusing on healthy lifestyle habits, and regularly monitoring your blood sugar.
• If you have type 2 diabetes and bipolar disorder, make sure your specialists work together. Many people will see one doctor for their bipolar care and another for their diabetes care. Your diabetes care provider might not even be aware of your psychiatric diagnosis. But the results of this study and others suggest that bipolar disorder influences diabetes management. You want your healthcare team to communicate and consider how having both conditions might impact your treatment plan. 
• Take signs of possible diabetes seriously. This study is another reminder to be aware of the physical health complications linked with bipolar disorder. These findings suggest that if you do get type 2 diabetes, it’s especially important to get support since your blood sugar may be particularly difficult to manage. Tell your doctor if you notice what are, according to Mayo Clinic, hallmark symptoms of type 2 diabetes, like:

• Feeling thirstier than usual
• Urinating more
• Being hungrier
• Losing weight
• Unexplained fatigue
• Blurry vision
• Wounds that take a long time to heal
• Getting sick a lot
• Numb feet or hands
• Dark skin patches in your armpits or neck

• Hyperglycemic crises are serious, but rare. It’s scary to hear that you might be at increased risk for a blood sugar emergency. But keep in mind that these are still rare events for everyone. In the group of people with bipolar disorder, just under 2.7 percent of people had a hyperglycemic crisis during this almost decade-long study. So while this study suggests that you may be more vulnerable to these diabetes emergencies than someone without bipolar disorder, it doesn’t mean you’ll definitely experience a health crisis.

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What Childhood Abuse and Exercise Have to Do With Bipolar Disorder

You’ve had a grueling episode of depression. Your medical chart says “major depressive disorder.” You start treatment. But if you’re among the estimated 1 in 12 that research suggests will eventually have a manic or hypomanic episode and get a revised diagnosis of bipolar disorder, you could be missing years of proper treatment, which means losing out on years of feeling your best. 

Right now, there’s just no way to tell if a first episode of depression is part of bipolar disorder or not. But researchers are trying to change that and reduce misdiagnoses. One international research team set out to understand whether two factors in particular — being abused as a child and an exercise habit as an adult — could interact in surprising ways to predict if what first appears to be depression really is bipolar disorder lying in wait. Their findings were published in the journal Translational Psychiatry.

What the Research Says

To understand what factors are linked with “progressing” from major depressive disorder to bipolar disorder, the research team decided to track every single person who came to a mental health specialty hospital located in southeastern China over a 4.5-year period. 

More than 1,000 people arrived with a diagnosis of major depressive disorder. The researchers gathered as much information about this group as possible through surveys and clinical interviews, including sensitive questions about the maltreatment people experienced as children and their exercise habits today. 

The researchers suspected that those who experienced childhood abuse, particularly emotional abuse and sexual abuse, would be more likely to end up with a bipolar disorder diagnosis. Both types of childhood abuse are more common in bipolar disorder than major depressive disorder, research suggests.

But they weren’t only interested in factors you can’t control. The research team also wanted to know how exercise might impact the link between childhood abuse and bipolar disorder. 

What does exercise today have to do with abuse suffered decades ago? At first, this link might seem random. But other research has found that exercise seems to help manage the emotional reactivity that can come with surviving childhood emotional abuse. It’s not yet clear exactly why it works, but evidence suggests that physical activity might help by regulating the brain, reducing inflammation, and lowering stress.

By the end of the study, just under 60 people initially diagnosed with major depression ended up with an updated diagnosis of bipolar disorder. When the research team analyzed the data, here’s what they discovered about this group:

• Having experienced childhood sexual abuse made people 15 percent more likely to get an updated diagnosis of bipolar disorder.
• Having experienced childhood emotional abuse (like being frequently called stupid, lazy, or ugly) meant a 5 percent higher risk of progressing to bipolar disorder.
• The increased risk associated with childhood emotional abuse disappeared for those who said they exercised one or more times per week.

The risk of progressing from major depressive disorder to bipolar disorder was still small overall — each year, only about 4 percent of people in the major depressive disorder group got a revised diagnosis. But the findings suggest that childhood emotional and sexual abuse help predict who will be in this minority. And, importantly, the results also suggest that you may be able to reduce your odds with habitual exercise. 

This study is just the tip of the iceberg. Future research needs to look into whether the links with childhood abuse and exercise differ depending on whether you have bipolar 1 or 2, if the type of physical activity makes a difference (Is yoga just as helpful as running?), and if the results still hold with larger, more diverse groups of people. 

Why It Matters

Being misdiagnosed as having major depressive disorder when you have bipolar disorder isn’t just a medical charting mix-up. It has real-life, serious consequences. For example, some antidepressants that are helpful if you have major depressive disorder can up your risk of mania or suicide if you really have bipolar disorder. 

If the links found in this study are confirmed, screening for certain types of childhood abuse could help cut down on misdiagnosis and help you access critical care. Plus, if you learn that your childhood puts you at a higher risk for progressing to bipolar disorder, you can consider creating an exercise habit to reduce your risk.

What This Means for You

• Surviving childhood abuse suggests a need for careful mental health monitoring today. If you’re diagnosed with major depressive disorder and have experienced childhood emotional or sexual abuse, these results suggest that it’s particularly important for your mental health care team to watch for the symptoms of mania or hypomania that could signal bipolar disorder. Being aware of the possible link could shorten your time to accessing the correct diagnosis and care. 
• Exercise may support mental health after a depressive episode. You can’t control what someone did to you when you were young. But it can be empowering to learn that, according to the results of this study, there’s something you can do today to help reduce the negative mental health impact of those circumstances: Have an exercise habit. Importantly, the exercise doesn’t have to be intense. You don’t need to run a 5K every morning or pound weights five afternoons a week. The results suggest that just once per week — a much more manageable goal — was enough to erase the increased risk of progressing to bipolar disorder from major depressive disorder for those who had survived childhood emotional abuse. 

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Bright Light Therapy Helps Bipolar Depression Without Triggering Mania, New Study Finds 

You might know that SAD lamps (therapeutic bright lights) can make you feel less, well, sad if you have seasonal affective disorder (SAD), a type of depression that follows a seasonal pattern. 

It’s not as well known that bright light therapy also helps ease symptoms of nonseasonal depression, including bipolar depression. 

But, as with other treatments for bipolar depressive episodes, the question is: What’s the best dose for easing depression symptoms without triggering mania? New research published in the Journal of Clinical Psychiatry offers insights. 

What the Research Says

Bright lights can boost your mood during a bipolar depressive episode, according to Harvard Health. But if you wanted to actually use the treatment, how would you do it? 

Practical guidelines for bipolar disorder don’t yet exist. It’s unclear how long to use bright light therapy or whether there’s an ideal time of day for it. 

Researchers in France set out to help answer these questions. They asked 34 people living with bipolar who were currently in a depressive episode to try bright light therapy for 10 weeks. 

Because the research team wanted to understand how long you should do the treatment for, they had people wear bright light glasses for different amounts of time. Some people started with 7.5 minutes in the glasses and gradually increased to 45 minutes over a couple of months. Others jumped right in at higher doses. 

To see if the time of day changed the effects of treatment, about half of the group (18 people) used light therapy glasses around 8 am, while the other half (16 people) used them around noon. 

Along the way, people answered mood surveys so the research team could track how they were doing. Here’s what they learned:

• 45-minute sessions of light therapy appear to be safe. Whether people gradually increased their time with the light glasses to 45 minutes or started there, the researchers didn’t find that this amount of light therapy was linked to an increased risk of mania. 
• Morning and midday light therapy are equally safe. Two people did experience hypomania, one in the morning group and one in the midday group. Five more people noticed a small bump in manic symptoms that didn’t rise to the level of an episode (three in the morning group, two in the midday one). Since the results were about the same in both groups, it suggests that the time of day isn’t a significant factor in determining whether someone will develop hypomania. 
• Morning sessions might be most helpful for reducing depression symptoms. While people in the morning and midday groups both had meaningful improvements in their mood, those who used light glasses around breakfast time had a bigger boost than those who waited until lunch. 
• Any hypomania symptoms went away quickly when treatment was reduced. When people had hypomania symptoms, the researcher asked them to dial back the time they spent using their light glasses (from 45 minutes to 30 minutes). Within three days, without having to do anything else differently, they felt more like themselves.
• People said the side effects weren’t bad. About 80 percent of people said they had no side effects at all, which is probably partly why more than 90 percent said the treatment was acceptable. Since side effects can be so challenging in other bipolar disorder treatments, this is encouraging news. 

Why It Matters

In bipolar disorder, your circadian rhythm seems to be disrupted, according to a growing body of research. A review of related research suggests that bright light therapy is one way to impact your body’s internal clock and, potentially, treat bipolar disorder. But bright light might also trigger mania, so getting the dose and timing right is important. This study is one step toward clarifying recommendations for the safe use of bright light therapy to treat bipolar depression. 

What This Means for You

• Someday soon, a pair of bright light glasses might have a place in your treatment toolbox. These results suggest that not only does light therapy ease bipolar depression symptoms, but it’s unlikely to trigger a manic episode. The kind of glasses used in the study, from the brand Luminette, are already available over-the-counter, meaning once more research confirms the best way to use light therapy in bipolar, you’d be able to start using them as needed right away. 
• Bright light therapy isn’t a DIY treatment. Everyone in the study was carefully monitored to see how they responded to the treatment. Although no one experienced full-blown mania, some people did experience an increase in manic symptoms, which necessitated adjusting their time using bright light glasses. This isn’t the kind of thing you should try on your own. 
• Bright light therapy is not a replacement for medication. This study looked at light therapy as an add-on treatment for bipolar depression. All participants were on standard doses of mood stabilizers, too.

Editorial Sources and Fact-Checking

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