Memory failings impede bipolar diagnosis
medwireNews: The ability of the Mood Disorder Questionnaire (MDQ) to identify bipolar disorder is compromised by patients being able to recall only the most recent episodes of mania, research shows.
The MDQ was very accurate for detecting manic or hypomanic episodes that had occurred in the previous 2 years, but patients' recollection of lifetime episodes was so variable that only 57.6% of those who initially reported an episode reported it again when retested just 2 years later.
"This is alarming as a prior history of manic symptoms also has major implications concerning, for example, the clinical course of bipolar disorders," say lead researcher Lynn Boschloo (University Medical Center Groningen, the Netherlands) and team.
"As recommended by others, involving third parties (e.g., families or caregivers) in the assessment of manic symptoms might be a more reliable strategy for gathering information on previous manic symptoms," they write in the Journal of Affective Disorders.
"A strength of this method would be that it may not only overcome problems in recalling symptoms but also difficulties due to a lack of insight into manic symptoms as often observed in bipolar patients."
The study involved 2087 participants in the Netherlands Study of Depression and Anxiety; around two-thirds had depression, with 3.9% reporting a lifetime manic or hypomanic episode and 1.4% a recent episode when assessed with the Composite International Diagnostic Interview (CIDI).
Compared with the CIDI, the MDQ was just 61% sensitive for lifetime manic/hypomanic episodes at the standard cutoff of endorsing at least seven items, although it was 81% specific. Reducing the cutoff to at least four items raised the sensitivity to 94% but reduced the specificity to 57%.
However, the MDQ was able to detect manic/hypomanic episodes that occurred within the preceding 2 years, with the standard cutoff (≥7 items) producing the optimal performance, giving a sensitivity of 83% and a specificity of 82%.
For patients with recent symptoms of mania, the MDQ may therefore be "an adequate, time-efficient screening instrument," say Boschloo et al.
They add: "Consequently, screening with the MDQ may provide the opportunity to identify those patients suffering from a recent (hypo)manic episode at an earlier stage and offer them more suitable and effective therapy."
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Eleanor McDermid, Senior medwireNews Reporter