|Year : 2020 | Volume
| Issue : 3 | Page : 103-109
Clinical, cognitive, and sociodemographic variables in melancholic versus nonmelancholic depression
Samin Sameed1, Mathews Joseph Panicker2, Rohan Dilip Mendonsa3, Anil Kakunje2, Ravichandra Karkal2
1 Psychiatrist, General Hospital, Ernakulam, Kerala, India
2 Department of Psychiatry, Yenepoya Medical College, Yenepoya University, Mangalore, Karnataka, India
3 North Western Mental Health, The Royal Melbourne Hospital, Parkville, Australia
|Date of Submission||28-Apr-2020|
|Date of Decision||31-May-2020|
|Date of Acceptance||29-Jun-2020|
|Date of Web Publication||27-Jul-2020|
Mathews Joseph Panicker
Department of Psychiatry, Yenepoya Medical College, Yenepoya University, Mangalore, Karnataka
Source of Support: None, Conflict of Interest: None
Introduction: The “biological” symptoms in some depressive illnesses are loss of sleep, appetite and weight, psychomotor changes, decreased libido, etc., Those in the remaining forms of depression include anxiety, phobias, and obsessional symptoms. These two groups of symptoms constitute melancholic and nonmelancholic depression, respectively. This research aimed at studying the clinical, cognitive, and sociodemographic profiles in melancholic and nonmelancholic depression. Methods: This cross-sectional, observational study was conducted in a tertiary care teaching hospital among 60 in-patients over a period of 1 year following clearance from the Institutional Ethics Committee. Among the total 60 participants enrolled, 30 met criteria for depression with melancholic features and 30 had depression without melancholic features according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Patients were administered a specialized pro forma to record the demographic, medical, psychiatric, and other relevant clinical data. Hamilton's Depression Rating Scale was used for assessing severity of depression; Clinical Outcomes in Routine Evaluation (CORE) Questionnaire was used to assess melancholic features; and cognitive assessment was done using Mini-Mental State Examination (MMSE) and semantic verbal fluency test. Suicide ideation was assessed using the Modified Suicide Ideation Scale. Results: Our study showed a statistically significant difference in CORE score, MMSE, semantic verbal fluency, and Modified Suicide Ideation Sscale scores, all with P < 0.001 in the melancholic group compared to nonmelancholic group; however, Hamilton depression scores were not significantly different between them with P < 0.264. Conclusion: Melancholic depression differs from nonmelancholic depression in various clinical and cognitive aspects, with more cognitive deficits and suicide ideation in the melancholic group.
Keywords: Clinical profile, melancholic depression, nonmelancholic depression, symptom profile
|How to cite this article:|
Sameed S, Panicker MJ, Mendonsa RD, Kakunje A, Karkal R. Clinical, cognitive, and sociodemographic variables in melancholic versus nonmelancholic depression. Soc Health Behav 2020;3:103-9
|How to cite this URL:|
Sameed S, Panicker MJ, Mendonsa RD, Kakunje A, Karkal R. Clinical, cognitive, and sociodemographic variables in melancholic versus nonmelancholic depression. Soc Health Behav [serial online] 2020 [cited 2020 Aug 8];3:103-9. Available from: http://www.shbonweb.com/text.asp?2020/3/3/103/290977
| Introduction|| |
One of the main causes of disability worldwide is the common mental disorder depression which has affected around 264 million people around the globe. According to the World Health Organization, depression is the leading cause of disability as measured by years lived with disability (YLD) and is the fourth leading contributor to the global disease burden. According to the disability-adjusted life years, depression is ranked presently as the second most cause calculated for age groups 15–44 years and is further on the rise. By 2020, it is predicted that depression will reach the second place as calculated for all ages.
Melancholic depression is often considered particularly to be a severe form of depression. According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), the symptoms of melancholia include loss of pleasure in all, or almost all, activities, lack of reactivity to usually pleasurable stimuli, a distinct quality of depressed mood, depression that is regularly worse in the morning, early-morning awakening (at least 2 h before usual awakening), marked psychomotor agitation or retardation, significant weight loss, and excessive or inappropriate guilt. In addition, patients may experience cognitive processing problems (decreased concentration and inattention) as well as motor signs such as agitation and retardation.
Depression has also been shown to cause deficits in episodic memory and learning. This finding is consistent across most studies and appears to involve both explicit verbal and visual memory in patients with both melancholic (endogenous) and nonmelancholic (nonendogenous) depression. Earlier, studies examining impairment in executive tasks produced conflicting results, but more commonly, severe depression was associated with significant impairment.,, In a study by Beats et al., the subjects showed prominent cognitive impairment in verbal fluency and attention set-shifting. Many studies showed impairment in executive functioning with depression, while other studies showed prior depression predicts poorer cognitive functioning later in life.,, However, some studies do not show this association., A study by Austin et al. comparing melancholic and nonmelancholic depression using the Clinical Outcomes in Routine Evaluation (CORE) Questionnaire and Newcastle System showed selective executive deficits in subjects with melancholic (endogenous) depression, compared with nonmelancholic (nonendogenous) depression. In a case–control study by Gentil et al., which compared the efficacy and tolerability of antidepressants in out-patients with and without melancholic depression, the pretreatment scores of Hamilton Depression Rating Scale (HAM-D), Montgomery and Asberg Depression Rating Scale, and Clinical Global Impression–Severity scale (CGI-S) were significantly greater in the melancholic group.
Studies have earlier evaluated the relation between severity of depression and neurocognitive task scores, findings of which are often conflicting, point to the relevance of this study. Since not much research has been done to investigate the difference in cognitive deficits among the different subtypes of depression, this study would help us better understand melancholic depression and its associated cognitive dysfunction.
The aim was to study the clinical, cognitive, and sociodemographic variables in patients with melancholic versus nonmelancholic depression
| Methods|| |
This was a cross-sectional, observational study conducted at the Department of Psychiatry in Yenepoya Medical College Hospital, Mangalore, India, over a period of 1 year which included in-patients who presented to the department with depression. Institutional Ethical Committee approval (YUEC 208/10/12/2013) was sought before commencing the study and written informed consent was obtained from all participants. All enrolled patients were then divided into two groups: Group 1 being those with depression with melancholic features and Group 2 with depression without melancholic features. All patients aged between 18 and 60 years satisfying DSM-5 diagnostic criteria for depression with and without melancholic features and having HAM-D score >7 were serially recruited for the study. Patients with comorbid anxiety disorders, substance use disorders (except nicotine), bipolar affective disorder, neurological disorders, and intellectual disability were excluded from the study.
All the subjects (n = 60) underwent a thorough physical and mental status examination. The sociodemographic and clinical information was collected and recorded using a specially designed pro forma for the clinical study. The patients were categorized into different socioeconomic classes according to the revised Modified BG Prasad Socioeconomic Classification scale. The patients were diagnosed with Depression with Melancholic features or Depression without Melancholic features according to DSM-5 criteria for the same. HAM-D was used to assess the severity of depression, CORE questionnaire to measure the melancholic features., Assignment to melancholic and nonmelancholic groups was further validated by CORE measure, Mini-Mental State Examination (MMSE), and semantic verbal fluency test (SVFT) for cognitive function assessment., The Modified Scale for Suicidal Ideation (MSSI) was used to assess suicidality.
Data were entered into Microsoft Excel and analyzed using SPSS Version 23 (IBM Corp. Released. IBM SPSS Statistics for Windows, Version 23.0. Armonk, NY, USA: IBM Corp.). The analysis was done in terms of frequency percentage for demographic data and Pearson Chi-square for comparison of the categorical variables.
| Results|| |
The results of the 60 in-patients considered in the study are portrayed below. The sociodemographic features namely age, the years of formal education, gender, education and marital status, occupational status, religion, locality, the type and socioeconomic status of each family including family history of any depressive illness, and those with tobacco use disorder were compared between the two groups in [Table 1]. Independent samples t-test was done for age distribution and years of formal education and Chi-square test was done for the remaining sociodemographic variables to find their association with the two groups.
The mean age in years and standard deviation (SD) of patients with depression with melancholic features was 40.33 (SD ± 12.968) years and that of depression without melancholic features group was 40.77 (SD ± 11.927) years and there was no statistically significant difference between the two groups (P = 0.893). The mean years of formal education attained by participants under depression with and without melancholic features were 6 and 4 years, respectively, with a SD of 3.601 for the former and 3.443 for the latter. P value was analyzed by independent sample t-tests and confirmed that there was no statistically significant difference between the two groups, P = 0.423.
Of the total participants enrolled under depression with melancholic features, females constituted 60%, whereas they constituted 63.3% in the other group. Chi-square test was done to see if there was any association between gender and the two groups of depression and was found to have no statistical significance with P = 0.791.
Similarly, Chi square test was done to find the association for the remaining sociodemographic variables between the two groups and there was no statistically significant difference found between them.
The mean scores of all the five scales were computed for both the groups [Table 2]. These scales were used to assess the clinical and cognitive variables of all participants in the two groups. The difference in mean scores was found to be statistically significant for all the scales with P < 0.001 except for HAM-D Scale for which P = 0.264.
|Table 2: Comparison of mean scores of scales that assess cognitive and clinical profile|
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| Discussion|| |
The two diagnostic groups in our study namely melancholic and nonmelancholic were quite similar in terms of sociodemographic profile. However, the melancholic group showed certain characteristics which were significantly different compared to the nonmelancholic group.
The MMSE scores were significantly lower in the subjects with melancholic depression which imply that cognitive deficits are common. The findings are similar to many other studies which showed cognitive deficits in depression, more so in melancholic and severe forms of depression. A Study by Austin et al. showed selective executive deficits in patients with melancholic depression compared with nonmelancholic depression using the Newcastle system and CORE questionnaire. Studies done by Michopoulos et al. and others found that patients with melancholic depression exhibited deficits in a variety of domains, including memory acquisition, explicit visual and verbal memory, mental flexibility, set-shifting, selective attention, concept formation, and multitasking when compared to those with nonmelancholic depression.,,, Studies have also shown that even after recovery from the depressive episode, deficits in different cognitive functions remained in patients with melancholic depression. The other interesting finding of our study was that the SVFT scores were significantly lower in the melancholic group compared to the nonmelancholic group. Verbal fluency has been an important component of neuropsychological screenings for executive functioning and linguistic skills., The poor performance on semantic or phonetic verbal fluency test may indicate deficits in frontal lobe function as it is the brain region associated with executive commitment. The test thus requires an elaborate retrieval of words from conceptual memory involving specific areas of the brain in a restricted time frame. Therefore, the ability to retrieve correctly a limited set of words demands more planning, monitoring, judgment, and decision-making, as irrelevant information has to be inhibited and correct responses have to be selected. Subjects with melancholic depression may not be able to make this organized thinking and it is understandable considering the cognitive underpinnings associated with severe depression. A follow-up study on cognitive function after clinical remission in patients with melancholic and nonmelancholic depression showed that the cognitive deficits in verbal and semantic fluency remained only in the melancholic group. The third important finding in our study was that the melancholic group differed significantly from the nonmelancholic group in terms of its scores on different items in CORE. The findings show that subjects with melancholic depression (4.77 [SD ± 1.547]) are more likely to have agitated behavior compared to subjects with nonmelancholic depression (1.8 [SD ± 0.997]).
The melancholic subjects (mean score of the core retardation = 6.43 [SD ± 1.906]) are more likely to have slowed movements, decreased facial expressions, postural slumping, and slowing of speech rates than nonmelancholic group (mean score = 3 [SD ± 1.203]).
The mean score of the core noninteractiveness was 6.47 (SD ± 2.446) in the melancholic group and 3.97 (SD ± 1.217) in the nonmelancholic group, suggesting that participants in melancholic depression are more likely to have decreased interaction, reactivity, decreased attentiveness, decreased talk, and decreased length of verbal responses.
The MSSI scores were comparatively lower in participants with melancholic depression suggesting an association between suicidality and melancholic depression. This suggests that subjects with melancholic depression are at a higher risk of attempting/committing suicide which is similar to the findings in studies done by Caldieraro et al. and Van Praag and Plutchik., A similar study done by Goldney et al. assessed for melancholia in 100 female suicide, of which one-third were classified with melancholia. A study using DSM criteria for melancholia found an association of this subtype with more serious past suicide attempts and probability of future attempts; however, it is difficult to predict which depressive patients will attempt suicide. However, another review by O'Leary suggested that individuals classified with melancholia may not be at greater risk for suicide. It appears that certain melancholic symptoms, such as guilty feelings, loss of interest, and pervasive anhedonia may better predict suicidality than RDC- or DSM-based classification. Over 3500 patients were monitored over a 25-year period in the Swedish Lundby Study. The records of 28 subjects who successfully committed suicide were analyzed and revealed that 10 out of the 14 with a depressive diagnosis experienced a number of melancholic features. Thus, while the data are not uniform in suggesting that melancholia may be associated with elevated suicide risk, clinicians should be aware of the possibility. In our study, we assessed for severity of depression among the melancholic and nonmelancholic groups using HAM-D and there was no statistically significant difference (mean score of melancholic group: 20.7 [SD ± 2.087] and nonmelancholic group: 20.13 [SD ± 1.795]).
The two groups did not differ by severity of depression or duration of current episode in a study by Parker et al. which is similar to our findings. This however was in contrast to findings done by Caldieraro et al. which showed a statistically significant difference in the severity of depression assessed by HAM-D, as scores were lower in the group with melancholic depression.
Melancholic and nonmelancholic patients did not differ by gender as per a study done by Parker et al. The reason behind this may be explained by the help-seeking behavior in both genders. However, few studies have shown that the help-seeking behavior in men is less compared to women. Hilderbrandt et al. reported that melancholic depression was more frequent among men than women, suggesting that fewer men with melancholic depression may end up getting treated. The fact that completed suicides are more common in men may be related to this decreased help-seeking behavior and that it has been reported in studies including this study that suicidal ideations are more common in melancholic depression. A common finding is that the rates of melancholia increase with age, leading some to propose that biological correlates of aging may play a role in producing melancholic symptoms. The levels of serotonin or dopamine, neurotransmitters associated with the neurophysiology of depression, tend to be inversely related with age. There was no statistically significant difference in marital status between the two groups in our study. Studies show that in terms of interpersonal relationships people diagnosed with melancholic depression have less interpersonal sensitivity and more functional, intimate, and marital relationships than people with nonmelancholic depression.,
We found that there was no statistically significant difference in years of education or educational status between the two groups. Studies showed that lower educational attainment would be associated with a more severe depressive syndrome, with higher comorbidity, greater number of symptoms, more episodes, and earlier age of onset.,,,,,
In our study, there was no statistically significant difference between the two groups in terms of socioeconomic status or the locality of our participants. There is not much literature on the prevalence of the different depressive subtypes and locality; however, conflicting evidences are suggested by some studies showing more prevalence of depression in residents of rural areas and some reporting more prevalence in urban areas.,
There was no statistically significant difference between the two groups in terms of religion and occupation too. There is not much literature examining the relation between these and the depression subtypes.
There was no statistically significant difference in terms of nicotine abuse among the two groups in our study. However, in a study by Leventhal et al., melancholic depression in comparison to undifferentiated and atypical depression was associated with a significant 1.4- and 1.9-fold increase in the risk of comorbid nicotine dependence, respectively.
No statistically significant differences were found while comparing the family history of depressive illness among the two groups. However, based on a literature review, Zimmerman et al. suggested that the melancholic construct is associated with a greater family history of depression. The Depression and Bipolar Disorder Information Australia-Black Dog Institute describes two different types of melancholic depression, structural and functional, of which functional melancholia has been suggested to be associated with a strong family history of depression. However, we did not differentiate the two diagnostic groups based on family history of depressive illness. Our relatively small sample size (Group 1 = 30, Group 2 = 30) could have resulted in a higher type one error, which can explain the nonsignificant differences in terms of sociodemographic profile and other related factors. However, the effect sizes of these characteristics between the groups could be very small; hence, our study would have failed to pick up.
The strengths of the study are its sampling method and the use of multiple, comprehensive tools to assess depression which are a part of its scientifically sound methodology. We used consecutive sampling method to reduce the sampling bias. We have also used standardized diagnostic criteria for appropriate diagnosis as well as valid measurement scales to assess depression and cognitive functions of our participants. The limitations of the study are its cross-sectional study design and a relatively small sample size. Another limitation is that the study was conducted in a tertiary care hospital where most of the patients would have been initiated on medications prior to the start of the study which could have improved the psychomotor disturbances by the time we assessed them.
| Conclusion|| |
Melancholic and nonmelancholic depression shared similarities in sociodemographic characteristics and severity of depression; however, the two groups were found to be significantly different in terms of cognitive function deficits as well as changes in psychomotor activity and suicidal ideations. This study further stresses upon the importance of melancholic depression as an important subtype requiring further research so as to help us better understand the nature of depressive disorders.
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2]