Quiet BPD in Teens: Signs, Symptoms & Treatment Options

What Causes Quiet BPD?

There is no single cause of BPD, quiet or otherwise. The leading theories suggest that BPD is a mixture of both genetics and environmental factors. Because quiet BPD is a presentation of BPD rather than a separate condition, its causes are the same as those behind the disorder generally.^[3]

Biological Factors

One study found that the likelihood of both relatives having BPD increased with genetic relatedness. Concordance was highest among identical twins, followed by non-identical twins, full siblings and half-siblings.^[4] 

These findings suggest that genetics plays an important role in BPD, but twin studies are not perfect. Identical twins often grow up with more similar experiences than non-identical twins. They usually live in the same house like other twins, but being identical means they may be treated the same by teachers, parents, friends, and peers. This can make it difficult to separate the effects of genetics from the effects of their shared environment.^[5]

This next point matters if you have been researching quiet BPD yourself. Researchers once thought certain genes linked to serotonin might be behind the disorder. But larger reviews have not supported this, and no specific gene has been tied to the condition.^[6] If you come across older material online making that claim, it has since been overtaken by better evidence.

Environmental Factors

A child’s environment plays a huge role in how BPD develops, with early trauma being at the center of this. Experiences of abuse, neglect, or bullying in childhood all raise a child’s risk. Research shows that much of this trauma comes from troubled family environments, and its effects are stronger when that same setting interacts with a child’s natural temperament.^[7]

What this means is that a child can carry the risk factors for BPD, made worse by experiencing a difficult upbringing.^[7] But it also means that two children in the same house, with the same experiences and difficulties, can have very different outcomes. This is important for you to understand as a parent if you’ve been searching for something you did wrong.

Is It Quiet BPD or Just Normal Teen Behavior?

Adolescence is already a time of significant emotional ups and downs, and many adolescent BPD symptoms also fit the pattern for expected teen behavior.

This can leave parents in a difficult position. You can clearly see that your child is struggling with their emotions internally, but you’re unsure whether what you’re seeing can be classed as “normal” or not. 

For a long time, it wasn’t only parents who were uncertain about this, but clinicians too. In the past, doctors were hesitant to diagnose a teenager with any form of BPD, including quiet borderline personality disorder. They were worried that symptoms like mood swings, internalized emotional dysregulation, self-criticism, or risk-taking might be mistaken for something more serious, like BPD.^[8]

Since BPD is a long-term condition, many preferred to wait rather than give a young person a label they feared might stick unfairly.

But that thinking has changed, and this is positive news for families who want answers sooner rather than later. Evidence suggests that BPD can be diagnosed just as reliably in teens as in adults. The same criteria apply, and the diagnosis holds up when clinicians look at the main areas BPD affects.^[8]

Even the DSM (Diagnostic and Statistical Manual of Mental Disorders), one of the main diagnostic manuals, states that a personality disorder can be identified before age 18 as long as the traits have been present for at least a year.