Confused,she turned to her therapist,who suggested that she had dysthymia,a mild version of persistent depressive disorder,or PDD.
Persistent depressive disorder is chronic depression that lasts for at least two years in adults.iStock
Stern,an author based in New York City,often writes about mental health,but she had never heard the term. She soon realised that she had experienced dysthymia on and off for decades. “I am not suffering from it right now,” she adds,“but I imagine I’ll live with it again.”
She decided to write about it in her newsletter,How to Live,describing what it felt like to exist in a “constant state of ‘emptiness’” and sharing the tools that eventually helped her feel better.
It is not well understood why some cases of depression persist,but experts can share what they know about PDD.
What is persistent depressive disorder?
Persistent depressive disorder is chronic depression that lasts for at least two years in adults. As with many types of mental illness,there are different levels of severity.
The term “dysthymia,” a Greek word that can mean “low spirits,” “moodiness” or “dejection,” is no longer included in the Diagnostic and Statistical Manual of Mental Disorders,or DSM,but it is still used by some mental health practitioners to refer to the milder form of PDD.
Marnie Shanbhag,senior director of independent practice at the American Psychological Association,says that less severe PDD is often diagnosed when people come to therapy for another issue,such as marital problems or job stress,and reveal that they feel an ongoing,low-level sadness,flatness or emotional numbness.
There may not appear to be a reason behind it. “You’re just sort of ‘meh,’” Shanbhag says. “And you get used to being that way.”
For Stern,clinical depression “knocks me out. I can’t get out of bed,shower,eat or walk my dog”. With dysthymia,however,she can still function. She may not want to do the dishes,for example,but she “won’t feel obliterated” by the task.
Those who have the more severe form of PDD,referred to in the past as chronic major depressive disorder,might be unable to get out of bed after a night of insomnia,lose their appetite,have such difficulty concentrating that they cannot get their work done,or feel too exhausted to clean the house or prepare dinner,says Dr Paul Appelbaum,a professor of psychiatry at Columbia University and the leader of the group that oversees revisions of the DSM.
It is difficult to know its full scope of the disorder because experts say the disorder tends to be under diagnosed.
How is it diagnosed?
PDD is diagnosed in adults who report feeling depressed for “most of the day,for more days than not,” for at least two years,Appelbaum says. And if they do find relief from their symptoms,he added,it does not last longer than two months.
Children and adolescents can also have PDD. (To make a diagnosis,Appelbaum says,the symptoms will need to have lasted for at least one year.)
“Like other forms of depression,it causes significant distress or impairment,and it is associated with an increased risk of suicide,” Appelbaum says.
Patients with the disorder will also experience at least two of the following symptoms:
How is it treated?
PDD is typically treated with therapy and antidepressants.
There isn’t a cure,but people can become “symptom-free,and the intensity of recurrences,if any,can be minimised,” Appelbaum says.
Because PDD can be long-lasting – and does not always disrupt a patient’s day-to-day life – those with the disorder may assume that their milder depressive symptoms are simply character traits.
“It’s hard to convince people that they’re not just the negative person in their family or the Debbie Downer,” says Dr Jessi Gold,a psychiatrist in St. Louis. But if someone is experiencing distress or symptoms that interfere with daily life,then it makes sense to seek treatment rather than to simply say,“This is the way I am,” she adds.
Stern can relate. When people she was close with asked how she was doing,she would tell them that she was fine,but,she says,“a profound sadness would rise to the top,letting me know I wasn’t fine at all”.
She urges those who feel consistently unmotivated,apathetic or lacking interest in things that they once enjoyed to seek help.
“You may feel alone,but you are not,” she says.
The New York Times
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