Kate Spade's tragic suicide has been viewed from many angles: the heartbreaking loss of a mother, wife and business partner; the loss of a fashion icon who changed the way we think about design; and the hard truth that suffering from mental illness is a challenge for many individuals no matter how much success or wealth they have.
But there's another angle that's underexplored: the role of gender in depression and bipolar disorder.
The exact medical diagnosis of Kate Spade's mental illness has not been revealed. Her husband, Andy Spade, said in a statement she suffered from anxiety and depression for years and did refer to it as a "disease." An older sister who claimed in interviews that Spade had manic depression is estranged from the family, other family members said this week, and they voiced serious displeasure with the sister's comments.
Psychiatrists and mental health experts stressed that it would not be appropriate or professional to speculate on Spade's diagnosis, but they did say more research needs to be conducted on the role gender plays in mental illness, whether it is major depressive disorder or bipolar disorder.
A study conducted in the early 2000s by well-known mental illness researcher Ronald Kessler of Harvard Medical School found that major depressive disorder is the leading cause of disease-related disability among women in the world, and depression is much more common among women than men. Kessler said women are also more likely to have anxiety disorders, not every anxiety disorder, but the ones that are associated with suicide, such as panic disorder and phobias, and post-traumatic stress from sexual assault.
"There are so many questions left about the risks for depression across a [woman's] lifespan and lifespan transitions," said Dorothy Sit, associate professor at Northwestern University Feinberg School of Medicine, whose main clinical research focus is on the development of treatments for women with mood disorders.
Although women and men are equally prone to having bipolar disorder, women are more likely to suffer from the depressed state versus the manic state, according to the Depression and Bipolar Support Alliance. A 1995 study in the Journal of Clinical Psychiatry found that although bipolar disorder is equally common in women and men, research indicates that approximately three times as many women as men experience rapid cycling. Women with bipolar disorder may have more depressive episodes and more mixed episodes than do men with the illness.
Women tend to suffer from bipolar II, a version of bipolar in which depression and hypomania are the two states, and rapid cycling between the states occur more often than in men, said clinical psychologist Dr. Justin LaPilusa.
Sit said the rapid cycling — patients transitioning from manic highs to depressive lows — can be so distressing that it contributes to increased suicidal thoughts. Depression can be so debilitating, it can often trigger increased suicide risk, Sit said.
"People who are bipolar kill themselves when they are flipping between depression and mania. That's why rapid cycling is so lethal," Kessler said.
Dr. Kathleen Cairns, a clinical psychologist, said that men and women experience many of the same symptoms, including insomnia, racing thoughts, hyperactivity and anxiety, but that women may feel more depressed.
"In my 30 years' experience in private practice, I have noticed that women tend to present as more depressed during their depressive episodes, and men tend to enter therapy during their manic episodes, which often involves substance abuse," Cairns said.
"Men tend to have a higher instance of externalizing disorders. ... Men are more likely to kind of act out," said Dr. Cara Gardenswartz, a clinical psychologist and founder of Group Therapy Los Angeles.
Extreme cases of bipolar disorder that result in suicide are most often a result of misdiagnosis, not failed treatment, Cairns said. Often, people with bipolar disorder are incorrectly prescribed antidepressants, which Cairns said are completely different than bipolar medication.
"That's not going to work. People can't stand it anymore ... the intrusive thoughts, the lack of sleep. They just want out of their body," Cairns said.
LaPilusa said that even if someone is diagnosed correctly with bipolar disorder, treatment may still fail due to factors that include underreporting symptoms, not taking medication consistently or at all, too little treatment or lack of protective factors in a patient's life.
"Even with an accurate diagnosis, it is hard to know when the patient is going to become suicidal," LaPilusa said. "It's impossible to monitor them 24-7 unless they're hospitalized."
Treatment doesn't always have to mean hospitalization.
"Most people with proper treatment can avoid hospitalization completely. Education is key for the patient and for those in his or her life," Gardenswartz siad.
A key characteristic of someone with bipolar disorder is depression symptoms, such as lack of concentration and difficulty getting out of bed, Gardenswartz said. They will also have a manic period, resulting in symptoms such as a period of intense creativity, rapid speech and perhaps engagement with sex or drugs, she said.
Severity of the disorder can depend on family history of the illness and stress levels. "Stress can absolutely bring on a depressive episode or a manic episode. ... It's what we call the trigger," Gardenswartz said.
Sit said that in many instances, for women she has worked with, it becomes clear that their first major experience of mental illness began much earlier than the time at which they sought treatment. "It could have developed years earlier but was only properly diagnosed a decade later," Sit said.
Women may be affected differently due to factors such as pregnancy and menopause and hormonal changes, LaPilusa said.
Sit said monitoring women in the periods directly after giving birth is critical to prevent major depressive episodes postpartum. The period directly after birth is high risk for a depressive episode that could result in hospitalization. And the same vigilance is required for menopausal transition periods. There may be genetic vulnerabilities linked to hormonal transitions as well that increase the risk of depression across a lifespan, Sit said.
But the research evidence on a correlation between hormonal changes and depression has never been strong, Kessler said. "There's lots of controversy about hormonal changes and gender differences in depression," he said, but his view is that there is no strong evidence that proves hormones play a role. "True postpartum depression is very rare. ... Real biological depression after pregnancy is like 1 in 500 or 1,000. The vast majority of people with postpartum don't help explain why women have more depression."
He points to another reason, which he says data does back up.
"Why is it that women have more depression than men? Studies show that when the position of women and men change, when women get the right to vote, for example, measures of income and sex equality, the gender difference in depression goes down."
"We can't talk about bipolar pertaining to Kate Spade, because we don't have data to suggest that," Sit said. "But we need to encourage people to seek treatment and consider a different diagnosis. ... Bipolar is not recognized quickly enough in women," she said.
The medical community, as well as mental illness sufferers and their support networks need to consider whether a diagnosis of major depressive disorder (unipolar disorder) is correct versus bipolar disorder, because use of antidepressant drugs for bipolar disorder will not work and could make the situation worse, Sit said.
Kessler said misdiagnosis is definitely a piece of the puzzle, but it is hard to know how much it contributes to suicides. But he did say that misdiagnosing bipolar disorder for unipolar depression is dangerous, because even though bipolar is much less common, people who suffer from bipolar have higher suicide rates.
Sit that that ultimately mental illness is not a medical issues founded on gender. "It's not just women but men also with unrecognized illness," she said.
"Do we need some special treatment for women?" Kessler asked. Research shows very little gender difference when it comes to treatment options and the key is getting people into treatment and getting patients to stick with treatment after initial failures.
There are certain treatments that work better for women, he said, pointed to interpersonal therapy. Meanwhile, men respond better to cognitive behavioral therapy. In layman's terms, that's the difference between talking things out and following a set of rules to modify behavior, while often also taking pills. And even though it sounds like a stereotype, Kessler said research backs it up. "The basic idea is that men don't really want to talk about emotions, they just want rules to follow, a pill. Women want to talk about it. And that works better. .. It's a noticeable difference, but not dramatic."
Other variables such as socioeconomics, individual personality and genetics are much more predictive of mental illness than sex, he said.
"What we need to do is improve treatment of depression and get more people into treatment. Rather than saying we need to do something for women, we need to do something for people," Kessler said. "Depression is an enormous problem. ... We still have massive undertreatment. Half the people depressed in America in a year never get treatment and of those who get treatment, a high proportion drop out."
Kessler said in most cases if a patient tries a variety of drugs, even after a first option fails, 80 percent to 85 percent of patients can recover from a mental illness. In a week that has seen two high-profile suicides, Kate Spade and Anthony Bourdain, Kessler said he is "far more hopeful that we will find proper treatment" and that the number of suicides resulting from depression will ultimately be insignificant statistically.
He expects precision medicine to hone drug treatments for individuals in the future, and with those developments on the way, "it's matter of getting them into care. The key factor is making sure people get into care and engage in treatment, and providing resources for communities."
— Additional reporting by CNBC's Eric Rosenbaum