No single treatment stands out as especially effective for borderline personality disorder, a mental illness that can involve self-harm and suicide attempts, according to two new reviews of recent studies.

BPD does appear to respond more strongly to certain kinds of psychological “talk” therapies, British researchers found. However, the psychological treatments that showed the most promise were relatively new and supported by “too few data for confidence,” the authors write.

Because both are complex, intensive therapies that require long-term staff training, “we believe that such treatments will only be available to a select few patients,” said co-author Mark Fenton.

The team, led by Conor Duggan of the University of Nottingham and Clive Adams of the University of Leeds, conducted separate reviews on psychological and drug therapies for BPD.

The reviews appear in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.

The team analyzed findings from seven studies on structured talking therapies, comprising 262 adult outpatients with either a formal diagnosis of BPD or at least three criteria for the illness.

People undergoing a treatment called dialectical behavior therapy appeared to have fewer suicide attempts or thoughts of suicide at six months compared to those in usual care. Introduced in 1991, the treatment involves individual psychotherapy sessions, telephone coaching, lengthy group therapy sessions and cognitive modification.

Treating patients in a day hospital unit geared to psychoanalytic treatment also seemed to “decrease admission and use of prescribed medication and increase social improvement and social adjustment,” the reviewers found.

Although both treatments are “difficult to apply to everyday care,” the researchers say that results so far suggest that “the problems of people with borderline personality disorder may be amenable to treatment.”

BPD is characterized by “an internal sense of emptiness and an inability to regulate emotion, going from high to low levels of emotion very quickly,” according to Scott Haltzman, M.D, a professor at Brown University. “These people tend to respond to the world with swings from rage to glee.”

Two percent of the general population and 20 percent of psychiatric inpatients have borderline personality disorder. Borderline patients are overwhelmingly female (75 percent).

“This group of people is often a challenge to health service providers,” said Fenton, who is also editor of the U.K.-based “Database of Uncertainties About the Effects of Treatments. He said that people with BPD have difficulty engaging in relationships, including relationships with therapists.

Unlike some other psychiatric conditions, there is no widely accepted drug regimen for borderline personality disorder.

“If offered medication, people with BPD should know that this is not based on good evidence,” the reviewers concluded.

The second review pooled results from ten small, short-term randomized studies on drug therapies for BPD. These studies involved 554 patients, both inpatients and outpatients

Studies of the various drugs used “show that antidepressants offered the best chance of improvement, but even here, results were not robust,” according to Fenton. “For ratings of anger, fluoxetine (Prozac) may offer some improvement over placebo,” the researchers say.

Although the antipsychotic drug haloperidol showed some improvement in symptoms of hostility, “the numbers are so small it is likely to be a false positive,” said Fenton. The reviewers do not recommend the use of antipsychotic drugs for borderline personality disorder outside of clinical trials.

Although the drug data were not encouraging, “that does not mean (medication) may not do considerable good, and there is no indication of significant harm,” the reviewers wrote. “People with BPD or their carers are in a position to lobby for and facilitate good research in this area.”

Binks CA et al. Psychological therapies for people with borderline personality disorder, The Cochrane Database of Systematic Reviews 2006, Issue 1.

Binks CA, et al. Pharmacological interventions for people with borderline personality disorder. The Cochrane Database of Systematic Reviews 2006, Issue 1.