This study confirms that residual symptoms are frequent in patients who achieve remission from an MDE, in line with Dombrovski et al. (2007)
. Our study participants endorsed on average 19.6 mood spectrum items and 8.0 panic–agoraphobic spectrum items at the point of remission as defined by the HRS-D17
. Interestingly, manic/hypomanic spectrum features, including psychomotor activation, mixed instability, and euphoria, were more frequent among females. In a recent study based on the same study population, Rucci et al. (2009)
found that the polymorphism of the 5-HTTLPR is related with the lifetime mania spectrum score only in women and that women with high scores on mania spectrum and the ‘SS’ genotype constitute a subgroup with higher severity of depression.
As previously suggested (Judd et al., 2002
), depressive symptoms wax and wane within the same patient along a continuum that can accompany the patient throughout life. Functional impairment and low quality of life follow the same direction of depressive symptoms so that only when patients are completely symptom-free psychosocially does functioning return to good or very good levels.
Core residual mood symptoms, as assessed with the HRS-D17, were associated with poor quality of life and functional impairment, whereas sleep problems and somatic/ psychic anxiety were not found in this population.
Interestingly, specific factors of mood and panic–agoraphobic spectra were related to quality of life and work and social functioning even after controlling for residual HRS-D17
symptoms. The mood spectrum factors include depressive mood, psychotic features and psychomotor retardation. The presence of items belonging to the ‘psychotic features’ factor of the MOODS-SR among nonpsychotic patients is not surprising as this factor, reflecting the spectrum approach to mood disorders, includes subtle and less severe aspects, such as feeling very vulnerable, guilty or remorseful, being preoccupied with one’s own problems, thoughts and feelings. Of note, psychotic features and psychomotor retardation have been described in a number of studies as clinical characteristics that are more common in bipolar depression, or in patients who convert to bipolar disorder over time, than in unipolar depression (Mitchell et al., 2008
The factors sociability-extraversion and euphoria were associated with better quality of life and better functioning. This result is consistent with the description of the ‘sunny side’ of hypomania with positive (driven euphoric) features (Akiskal et al., 2003
; Hantouche et al., 2003
). Such features are rarely perceived as a source of distress by patients (Akiskal et al., 2000
; Benazzi, 2003
; Akiskal and Benazzi, 2006
). Another report suggested that symptoms of hypomania are associated with significant increases in health service use, a need for public assistance and suicidal behaviour, thus denoting a ‘dark side’ with specific harmful dysfunctions (Judd and Akiskal, 2003
The panic agoraphobic spectrum factors associated with poorer quality of life and functioning include separation anxiety, loss sensitivity and fear of losing control.
It has been already showed that panic–agoraphobic spectrum symptoms predict delayed response to sequential treatment with psychotherapy and drugs in women with recurrent major depression (Frank et al., 2000
). A recent study has highlighted the synergistic contribution of depression, anxiety and somatization to functional impairment during an index episode (Lowe et al., 2008
). This study adds to the existing literature by providing evidence that specific features of the panic–agoraphobic spectrum are linked with impaired psychosocial functioning even when remission is achieved. The relationship between childhood and adult forms of separation anxiety and major depression is well known (Lewinsohn et al., 1997
; Wijeratne and Manicavasagar, 2003
). Our study suggests that these features could contribute to the maintenance of a low quality of life in patients who remit from a MDE. Panic–agoraphobic residual spectrum features are more common among female patients. This is in line with the findings of Verhagen et al. (2008)
, indicating that comorbidity with panic disorder is significantly more frequent in women than in men with a major depression.
A number of studies have proved that the lack of remission is associated with significantly higher psychosocial impairment (Murphy et al., 1987
; Ansseau et al., 2009
). The results of this study confirm the importance of residual features even when patients achieve clinical remission as assessed with the HRS-D17
To our knowledge, this is the first study assessing residual mood and panic–agoraphobic spectrum phenomenology in patients who remitted from an MDE.
We submit that the identification of residual spectrum psychopathology could help clinicians to identify sex-specific long-term pharmacological and psychotherapeutic strategies that might lead to more complete remission and, consequently, reduced risk of recurrence. Unfortunately, these aspects, especially when subthreshold, tend to be overlooked and underestimated by clinicians. The administration of the self-report spectrum measures allows a more accurate evaluation of the heterogeneous signs and symptoms that follow an MDE.