Clinical correlates of atypical depression and validation of the French version of the Scale for Atypical Symptoms (SAS)

The effects of ketamine on typical and atypical depressive symptoms

OBJECTIVE

Ketamine's effects on different dimensions of depressive symptomatology, including typical/melancholic and atypical depression, remain largely unknown. This study examined the effects of a single intravenous dose of ketamine on general depressive symptoms (measured using the Montgomery-Asberg Depression Rating Scale (MADRS), typical/melancholic symptoms (measured using the MADRS5), and atypical symptoms (measured using the Scale for Atypical Symptoms (SAS)).

METHODS

Data from 68 participants with treatment-resistant major depressive disorder (MDD) or bipolar depression were pooled from three separate, double-blind, placebo-controlled, crossover studies investigating ketamine's efficacy in depression. MDD participants were unmedicated; bipolar participants received therapeutic-dose lithium or valproate. Clinical symptoms were collected preinfusion and up to 14 days postinfusion. Effect sizes were calculated for days 1 and 3 postinfusion. The primary measures of interest for this exploratory analysis were total MADRS, MADRS5, and SAS scores. Individual symptoms were also analyzed in an exploratory manner.

RESULTS

Scores improved significantly at Day 1 postinfusion (MADRS: Cohen's d = 0.64; MADRS5: Cohen's d = 0.61; SAS: Cohen's d = 0.41) and continued to be significantly improved over placebo at Day 3 (MADRS: Cohen's d = 0.49; MADRS5: Cohen's d = 0.43; SAS: Cohen's d = 0.39). Effect sizes were greater for typical/melancholic than atypical symptoms at Day 1 postinfusion.

CONCLUSION

Ketamine appears to effectively treat both the typical/melancholic and atypical symptoms of depression, but may have early preferential effects for the former.

Prevalence and clinical features of atypical depression among patients with major depressive disorder in China

BACKGROUND

Little is known about the demographic and clinical features of the atypical subtype of major depressive disorder (MDD) patients in China. This study set out to investigate the prevalence of atypical depression in MDD patients in China, and identify its demographic and clinical features.

METHODS

The study was conducted in 13 major psychiatric hospitals or in the psychiatric units of general hospitals in China, and recruited a sample of 1172 patients diagnosed with MDD. The patients' demographic and clinical features and prescriptions of psychotropic drugs were collected using a standardized questionnaire designed for the study.

RESULTS

The prevalence of atypical depression was 15.3%. In multiple logistic regression analyses, compared to the non-atypical depression patients, the atypical depression patients were more likely to have depressive episodes with suicide ideation and attempts (OR = 1.49, 95% CI = 1.06, 2.10, P = 0.023), depressive episodes with psychotic features (OR = 2.15, 95% CI = 1.43, 3.22, P < 0.001), seasonal depressive episodes (OR = 1.77, 95% CI = 1.12, 2.78, P = 0.014), an earlier age of onset (OR = 0.98, 95% CI = 0.96, 0.99, P = 0.001), and lifetime depressive episodes (OR = 1.07, 95% CI = 1.01, 1.13, P = 0.020).

LIMITATIONS

The assessment of atypical features was not based on a validated rating scale.

CONCLUSION

Our results indicate that atypical depression is common in Chinese patients with MDD. MDD with atypical features may be more severe and debilitating than patients with non-atypical features.

Stability of the diagnosis of seasonal affective disorder in a long-term prospective study

BACKGROUND

Seasonal affective disorder (SAD) is mainly characterized by a seasonal pattern of depressive recurrences over the years. However, few studies have been conducted on the long-term course of patients with SAD, whose findings raised questions about the diagnosis stability over time. This study aimed to better characterize the diagnosis evolution, and determine prognosis markers.

METHODS

An initial cohort of 225 outpatients diagnosed as having a SAD, was assessed at baseline (T1) for clinical symptoms and response to bright light therapy. One hundred and nineteen patients (53%) were interviewed 2-12 years after (T2).

RESULTS

Of 119 patients reached at follow-up (T2), only 32 patients (27%) still fulfilled the DSM-IV criteria for a stable SAD (S-SAD). A large proportion (59%) of the follow up cohort was in remission and 14% still suffered from a non-seasonal mood disorder. Family history of depression, previous suicide attempt, carbohydrate craving and HAD-depression score at baseline were associated with a stable SAD (S-SAD) diagnosis at T2, the HAD-depression score being the only one still significantly predictive (p=0.025) of a later stable SAD, with a multivariate approach. Carbohydrate craving, a core symptom of SAD, showed a trend (p=0.100) to predict diagnosis stability.

LIMITATIONS

Only 53% patients from the initial cohort were assessed at follow-up.

CONCLUSIONS

Patients with eventual stable SAD show more subjective severity (higher HAD-Depression score) and carbohydrate craving at baseline. A low predictive validity of diagnosis criteria suggests that SAD is a temporary expression of a mood disorder rather than a specific disorder.

Beyond "somatization" and "psychologization": symptom-level variation in depressed Han Chinese and Euro-Canadian outpatients

The finding that people of Chinese heritage tend to emphasize somatic rather than psychological symptoms of depression has frequently been discussed in the culture and mental health literature since the 1970s. Recent studies have confirmed that Chinese samples report more somatic and fewer psychological depression symptoms compared to "Western" samples. The question remains, however, as to whether or not these effects are attributable to variation in all the constituent symptoms or to a subset. If the latter, there is the additional possibility that some symptoms might show a divergent pattern. Such findings would have implications for how cultural variations in symptom presentation are interpreted, and would also inform the cultural study of affective experiences more broadly. The current study addressed these issues in Chinese (n = 175) and Euro-Canadian (n = 107) psychiatric outpatients originally described by Ryder et al. (2008). Differential item functioning (DIF) was used to examine whether specific somatic and psychological symptoms diverged from the overall patterns of cultural variation. Chi-square analyses were used to examine atypical somatic symptoms (e.g., hypersomnia), previously neglected in this literature. No DIF was observed for the typical somatic symptoms, but Euro-Canadians reported greater levels of atypical somatic symptoms, and showed higher rates of atypical depression. DIF was observed for psychological symptoms-the Chinese reported high levels of "suppressed emotions" and "depressed mood," relative to their overall psychological symptom reporting. Chinese outpatients also spontaneously reported "depressed mood" at similar levels as the Euro-Canadians, contrary to prevailing ideas about Chinese unwillingness to discuss depression. Overall, the findings provide a more nuanced picture of how culture shapes symptom presentation and point toward future studies designed to unpack cultural variation in narrower subsets of depressive symptoms.