|Year : 2022 | Volume
| Issue : 2 | Page : 267-275
Comparison of cognition and alexithymia in patients of schizophrenia with and without comorbid alcohol use: A cross-sectional exploratory study
D Abhijeet Faye1, Rahul Tadke1, Sushil Gawande1, H Sudhir Bhave1, Vivek Chintaman Kirpekar1, Anirban Chatterjee2, Yashika Nathani1, Deepika Singh1
1 Department of Psychiatry, NKP Salve Institute of Medical Sciences and Lata Mangeshkar Hospital, Nagpur, Maharashtra, India
2 Department of Preventive and Social Medicine, All India Institute of Medical Sciences, Bhopal, Madhya Pradesh, India
|Date of Submission||07-Jul-2021|
|Date of Acceptance||21-Dec-2021|
|Date of Web Publication||08-Aug-2022|
Dr. D Abhijeet Faye
Department of Psychiatry (OPD-10), 2nd Floor, OPD Building, NKP Salve Institute of Medical Sciences and Lata Mangeshkar Hospital, Digdoh Hills, Hingna Road, Nagpur - 440 019, Maharashtra
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: Cognitive impairment and alexithymia are commonly associated with schizophrenia and alcohol use disorder independently. Both can lead to poor prognosis and recovery. In patients with dual diagnosis, this association can be more prevalent and severe. Materials and Methods: A total of 75 participants were grouped into two (35 each): Group A, a Schizophrenia group and Group B with comorbid alcohol use. Sociodemographic factors, clinical profile, cognitive functions, and alexithymia were compared between the two groups using semi-structured pro forma, Positive and Negative Syndrome Scale, Alcohol Use Disorders Identification Test (AUDIT), Montreal Cognitive Assessment (MoCA) Scale, Toronto Alexithymia Scale (TAS-20) (subcategorized into three subscales (1) “Difficulty describing feelings” (DDF), (2) “Difficulty identifying feeling” (DIF), and (3) “Externally-Oriented Thinking” and Brief Psychiatric Rating Scale. Statistical analysis was performed using the Chi-square tests and t-tests as applicable. P < 0.05 was considered statistically significant. Results: The mean age of the participants was 33.61 (standard deviation [SD]-8.11), mean duration of schizophrenia was 70.8 months (SD-47.5) and mean duration of alcohol consumption was 9.10 years (SD-7.7). MoCA score was significantly lower (mean-21.80, SD-2.98) and TAS total score was significantly higher in Group B (Mean-67.31, SD-8.10). DDF (Mean-19.28, SD-4.02) and DIF scores (Mean-22.86, SD-4.66) were significantly higher in alcohol group compared to nonalcohol group. Furthermore, MoCA score was significantly impaired and TAS total, DDF and DIF scores were significantly higher in participants with AUDIT score >8 (P < 0.05). Lower score on MoCA correlated with the higher score of alexithymia. Conclusion: Cognitive dysfunction and alexithymia were significantly more in patients of schizophrenia with comorbid alcohol use and positively correlated with the severity of alcohol use disorder.
Keywords: Alcohol use, alexithymia, cognitive dysfunction, schizophrenia
|How to cite this article:|
Faye D A, Tadke R, Gawande S, Bhave H S, Kirpekar VC, Chatterjee A, Nathani Y, Singh D. Comparison of cognition and alexithymia in patients of schizophrenia with and without comorbid alcohol use: A cross-sectional exploratory study. Ind Psychiatry J 2022;31:267-75
|How to cite this URL:|
Faye D A, Tadke R, Gawande S, Bhave H S, Kirpekar VC, Chatterjee A, Nathani Y, Singh D. Comparison of cognition and alexithymia in patients of schizophrenia with and without comorbid alcohol use: A cross-sectional exploratory study. Ind Psychiatry J [serial online] 2022 [cited 2022 Dec 2];31:267-75. Available from: https://www.industrialpsychiatry.org/text.asp?2022/31/2/267/353551
Schizophrenia, a chronic and progressive disorder is characterized by the positive, negative, affective, cognitive, and somatic symptoms. The literature mentions that, up to 75% of the schizophrenia patients have cognitive symptoms with consistent deficits in various domains. Problems with memory, attention and concentration, executive functions, motor skills, information processing speed, learning, and intelligence are common cognitive dysfunctions in schizophrenia. Primary symptoms: hallucinations and delusions can also occur secondary to cognitive deficits involving perceptual and attribution biases., Cognitive symptoms may affect overall prognosis, recovery, and rehabilitation process in schizophrenia. Alexithymia is a difficulty in identifying and expressing the emotions. It is a common occurrence in schizophrenia. Studies have shown that impairment in both cognitive and affective processes in schizophrenia can be related to alexithymia independently of one another. Individuals with schizophrenia have increased alexithymia as indexed by the performance task, difficulty in cognitive functioning and the specific clinical symptom of alogia. Alexithymia is also found to be more prevalent in schizophrenia patients having prominent negative symptoms, that in turn, are associated with more cognitive impairment.
Cognitive dysfunctions are similarly found in patients with chronic and excessive alcohol consumption, mainly affecting the episodic memory, executive functions, and visuospatial abilities. Studies show that alcohol-dependent individuals with severe cognitive impairment have least favorable prognosis. About 50%–80% patients of alcohol dependence can have cognitive impairment. Complications such as Wernicke's encephalopathy or Korsakoff's psychosis are also associated with cognitive dysfunctions. The prevalence of alexithymia in alcohol use disorder ranges from 45% to 67%, but the evidence regarding this association is limited. Literature shows that alexithymia can be a risk factor as well as a poor prognostic factor for alcohol dependence.
Thus, cognitive impairment and alexithymia are commonly present in schizophrenia as well as alcohol use disorder. Very little is known about the nature, pattern, and severity of cognitive dysfunctions in patients having dual diagnosis, although, it can be said that the co-occurrence of these disorders can further aggravate the cognitive impairment. This study aims to compare the above aspects in schizophrenia patients with those having comorbid alcohol use.
| Materials and Methods|| |
This was a cross-sectional single interview study carried out in a tertiary care hospital. After institutional ethics committee approval (Ethics Committee Registration Number: ECR/88/Inst/MH/2013/RR-16), participants were selected consecutively from psychiatry ward. Patients with diagnosis of schizophrenia and those with concurrent alcohol use in the age group of 18–60 years were included in the study. Participants excluded were those having serious illness making them unable to participate and those in delirium. Patients with intellectual disability, dementia and those having Axis I diagnosis other than Schizophrenia and alcohol use disorders were also excluded. The diagnosis of Schizophrenia and alcohol use disorder was based on Diagnostic and Statistical Manual for Mental Disorders, version 5 (DSM V) criteria. Participants were categorized into two groups: Group A included patients with Schizophrenia, whereas Group B included the patients of schizophrenia with comorbid alcohol use. After giving detailed information about the study, informed consent was obtained from the patients and/or family members. Each group comprised of 35 participants (70 total). Each interview took around 1 h. The study was conducted for 15 months duration from December 2018 to February 2020. The aims of the study were to compare the cognitive dysfunctions into two groups, to assess and compare Alexithymia in two groups and to find the correlation of cognitive function and alexithymia with sociodemographic and clinical profile in two groups.
Following tools were used for the assessment.
Semi-structured pro forma
It included sociodemographic details, clinical history about schizophrenia (duration, symptoms, type, and diagnosis), and details about alcohol use (duration, pattern, etc.,).
Positive and negative syndrome scale
This is a 30-item scale that provides balanced representation of positive and negative symptoms and gauges their relationship to one another and to the global psychopathology. It consists of 7 items for positive symptoms, 7 for negative and 16 for general psychopathology symptoms. While the absence of symptom is scored as 1, the rating points of 2–7 correspond to increasing levels of symptom severity. The scores for these subscales are derived by addition of ratings across the component items. Therefore, the range is 7–49 for positive and negative scales, and 16–112 for General Psychopathology Scale. The inter-rater and test-retest reliability is 0.80, and significant correlations emerge with corresponding criterion measures.
Alcohol Use Disorders Identification Test
The World Health Organization's Alcohol Use Disorders Identification Test (AUDIT) is a very reliable and simple screening tool used for the early detection of high risk (hazardous and harmful) drinking. It has three questions on alcohol consumption, three questions on drinking behavior and dependence and four questions on the consequences/problems related to drinking. Furthermore, there are supplementary questions which are not scored. They provide useful clinical information associated with patient's perception and awareness about alcohol problem. Scale gives idea about the degree of intervention required. It is a 10-item scale and the scoring is done as follows. Questions 1–8 are scored on a five-point scale from 0, 1, 2, 3, and 4, whereas questions 9 and 10 are scored on a three-point scale from 0, 2, and 4. The scores are recorded and total score is the sum of all the scores. Maximum score is 40. The risk is calculated based on the score. Low risk (0–7), risky or hazardous level (8–15), high risk or harmful level (16–19) and possible dependence (>20). Scale has good reliability and validity.
Montreal cognitive assessment
This is a 30 questions test requiring around 10–12 min for completion. Score ranges from 0 to 30, with a score of 26 and higher being considered normal. The scoring distribution is as follows:
Visuospatial and executive functioning
Five points, Animal Naming: 3 points, Attention: 6 points, Language: 3 points, Abstraction: 2 points, Delayed Recall (Short-term Memory): 5 points, Orientation: 6 points and score of 1 is added to the test-taker's score if he or she has 12 years or less of formal education. It helps to determine quickly whether a person has abnormal cognitive function. It has high sensitivity (>90%) and specificity (around 87%) in assessing cognitive impairment. Studies have shown that Montreal Cognitive Assessment (MoCA) is sensitive enough to detect cognitive impairment in patients with schizophrenia.
Toronto Alexithymia Scale-20
Toronto Alexithymia Scale (TAS), a 20-item instrument is commonly used to measure alexithymia. It has three subscales (1) “Difficulty describing feelings” (DDF) subscale is used to measure difficulty in describing emotions, (2) “Difficulty identifying feeling” (DIF) subscale is used to measure difficulty identifying in emotions, and (3) “Externally-Oriented Thinking” (EOT) subscale is used to measure the tendency of individuals to focus their attention externally. TAS-20 is a self-report scale and items are rated using a 5-point Likert scale with score 1 = strongly disagree and 5 = strongly agree. A total alexithymia score is the sum of responses to all 20 items, while the score for each subscale factor is the sum of the responses to that subscale. TAS-20 uses cutoff scoring: equal to or <51 = nonalexithymia, equal to or >61 = alexithymia. Scores of 52-60 = possible alexithymia. The scale demonstrates good internal consistency (Cronbach's alpha = 0.81) and test-retest reliability (0.77, P < 0.01). It has been found to be stable and replicable across clinical and nonclinical population.
Brief psychiatric rating scale
Brief Psychiatric Rating Scale (BPRS) is used to assess various psychiatric symptoms along with their severity. Psychiatric symptoms include depression, anxiety, hallucinations, and unusual behavior. Each item is measured along a seven-point continuum from “not present” to “extremely severe.” It can be scored from 0 to 6 or 1–7 and depending on the version, a score between a total of 18 and 24 symptoms are scored. Higher the score, more is the psychopathology.
The data were analyzed using RStudio – an integrated development environment for using R. Continuous data were described using means and standard deviations (SD), whereas categorical data were described using counts. Bivariate analysis was carried out using the Chi-square test and t-test as applicable. P < 0.05 was considered statistically significant.
| Results|| |
Two groups considered for comparison had 35 participants each. Group A included patients with Schizophrenia, whereas Group B comprised of patients with Schizophrenia and comorbid alcohol use. The mean age of the participants was 33.61 (SD-8.11), mean duration of schizophrenia was 70.8 months (SD-47.5), and mean duration of alcohol consumption (among alcohol use group) was 9.10 years (SD-7.7).
[Table 1] shows the demographic and clinical details of participants in Group A and Group B. Participants in both the groups were comparable and well matched with respect to almost all the sociodemographic and clinical factors. There was no statistically significant difference except for the BPRS and Positive and Negative Syndrome Scale (PANSS) scores which were significantly higher in group B with P < 0.05.
|Table 1: Demographic and schizophrenia details (all) versus alcohol consumption|
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Majority of the participants had multiple episodes, affect disturbances (restricted affect), and were on second generation anti-psychotic drugs.
When demographic and clinical details were compared in the Group B between nonharmful use of alcohol and harmful use of alcohol (AUDIT score <8 v/s >8), it was found that mean age of the participants was significantly higher in harmful alcohol users. Among nonharmful alcohol users, majority were married. Both the findings were statistically significant with a P < 0.05. PANSS total score; positive symptoms score and negative symptoms score were also significantly higher in harmful alcohol users compared to those with AUDIT score <8.(P < 0.05) [Table 2]
|Table 2: Demographic details (all) versus harmful use of alcohol (alcohol use disorders identification test score <8 versus > or =8)|
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[Table 3] shows that 72.8% (51) of the participants had MoCA score of <26 suggesting cognitive impairment. In TAS 20 scale, 72.9% (51) had “alexithymia,” 14.2% (10) had 'possible alexithymia, and 12.9% (9) of the participants had “no alexithymia.” On AUDIT scoring, 38.6% had score >8 suggestive of risky/problematic alcohol use, whereas 61.4% (43 out of 70) had score <8.
|Table 3: Frequency table for montreal cognitive assessment and toronto alexithymia scale categories alcohol use disorders identification test|
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[Table 4] shows the comparison of cognitive dysfunction and alexithymia in Group A and B. It was found that MoCA score was significantly lower in Group B (alcohol group) (Mean-21.80, SD-2.98) compared to Group A (P < 0.01) indicative of more cognitive impairment in participants of Schizophrenia with alcohol use compared to only schizophrenia group. TAS total score was significantly higher in Group B (Mean-67.31, SD-8.10) compared to Group A (p-0.01) suggesting higher alexithymia in participants of schizophrenia with comorbid alcohol use. When subgroups (domains) of alexithymia were compared between the groups, it was observed that DDF (Mean-19.28, SD-4.02) and DIF scores (Mean-22.86, SD-4.66) were significantly higher in alcohol group compared to nonalcohol group with P values of 0.001 and 0.04 respectively while no statistically significant difference was found for EOT score of alexithymia between the groups. Similarly, the presence of alexithymia was positively correlated with alcohol use compared to possible alexithymia and no-alexithymia (P = 0.008).
|Table 4: Montreal Cognitive Assessment, Toronto Alexithymia Scale categories and Alcohol use disorders identification test|
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Alexithymia score was significantly higher in participants with alcohol use irrespective of the clinical and sociodemographic characteristics. Alexithymia score was also found to be positively correlated with the negative symptoms score on PANSS (P < 0.01).
When AUDIT score (<8 and >8) was compared with MoCA and TAS scale, similar findings were observed. MoCA score was significantly impaired (lower) in participants with >8 score on AUDIT which indicates that more risky the alcohol use, lower is the cognitive score. Presence of alexithymia, TAS total score, DDF and DIF scores were significantly higher in those with AUDIT score more than 8 suggesting severe the alcohol use disorder, more is the alexithymia. EOT was not found to be having significant correlation with the severity of alcohol use.[Table 5]
|Table 5: Montreal Cognitive Assessment and toronto alexithymia scale values and categories versus harmful use of alcohol (alcohol use disorders identification test score <8 versus > or=8)|
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[Figure 1] is indicative of correlation between MoCA score and TAS score. It was found that lower score on MoCA correlated with the higher score of alexithymia on TAS 20.
|Figure 1: Montreal cognitive assessment versus Toronto alexithymia scale|
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| Discussion|| |
Although cognitive dysfunction is not utilized as a diagnostic criterion, it is considered as the strongest determinant of functional recovery in schizophrenia patients. It can precede, coincide, and even outlast the positive symptoms. It is therefore necessary to assess this construct for the better management of schizophrenia. Common cognitive impairments include problems with memory, attention, information processing speed, executive functions, and social cognition. Chronic alcohol consumption also leads to cognitive impairment such as problems with episodic memory, executive functioning, and visuospatial orientation which can impact abstinence and efficient management. It is therefore expected that the schizophrenia patients with comorbid alcohol use would have more cognitive impairment compared to those without comorbid alcohol consumption.
In this study, the population in two groups was comparable and well matched with respect to age, education, marital status, and other sociodemographic characteristics along with no significant differences in clinical profile except for the BPRS and PANSS scores. This helped in reducing the bias in the results that might have occurred due to influence by various patients' characteristics. Higher score on BPRS and PANSS could be explained as comorbid alcohol use disorder can increase the psychopathology or manifestation of symptoms in schizophrenia along with complicating its course and outcome.
This study showed that 72.8% of the participants had MoCA score <26 suggesting cognitive impairment. This is similar to the finding of other studies that observed the prevalence of significant cognitive deficit in 61%–78% in Schizophrenia patients.
Some recent studies reported a higher prevalence of substance use disorders and psychosis sharing common biological changes in brain that may affect the cognitive performance, response to treatment and can increase the risk of relapse. This explains the fact that schizophrenia patients, if have comorbid substance use, may show more cognitive impairment.
This study showed significantly higher level of cognitive impairment in patients of schizophrenia with comorbid alcohol use. A study by Ventriglio et al. found that, the cognitive functions in patients with schizophrenia were substantially more impaired than in healthy participants and slightly lower in those with a history of alcohol abuse.
Although schizophrenia and alcohol use disorder are commonly associated, it is not certain whether combination of the two lead to worsening of cognition compared to either disorder alone. The current available research findings are inconclusive and inconsistent, showing variable outcomes on tests of specific cognitive functions. The finding of some studies includes severe cognitive impairments in patients with dual diagnosis on certain cognitive tests., Cognitive impairment was even more profound in those with heavier alcohol consumption., Few studies found minor or insignificant differences with non-alcoholic schizophrenia patients. Specific cognitive deficits found among dual diagnosis patients include those in memory (verbal and working), executive functioning, set-shifting, facial recognition, and planning.,
There are several other studies that found more pronounced cognitive deficits in alcohol-dependent schizophrenia patients as compared to nondependent ones., In one meta-analysis, the authors concluded that in patients with the dual diagnosis of schizophrenia and alcohol abuse, predominant cognitive deficit associated was lower working memory, while many studies showed an additive effect of alcohol and schizophrenia on delayed verbal memory, sensory gating, and executive functioning.,
One more study assessing the neurocognition, symptomatology and functional skills in alcohol abusing schizophrenia patients of 40–80 years found that alcohol abuse in schizophrenia is associated with more impairment in various domains of functioning including memory, negative, and general psychopathology symptoms as well as adaptive functions. The study concluded that the only significant predictor of impaired functional status was “neurocognitive functioning.”
In this study, it is also found that severity of alcohol use correlated positively with cognitive impairment. When AUDIT score was compared with MoCA score, higher cognitive impairment was found in those with higher score on AUDIT. Studies also showed similar results with statistically significant cognitive impairment among DSM-IV-TR Schizophrenia patients who also met DSM-IV-TR criteria for alcohol abuse and greater cognitive deficits in severe alcohol abuse patients based on Michigan Alcohol Screening Test score for alcohol abuse.
Effects of specific treatments could not be assessed as all the patients received antipsychotic drugs. Furthermore confounding effect of factors such as impact of acute psychotic illness, current/recent alcohol use, and withdrawal was not assessed.
Alexithymia (difficulties in identifying and describing the emotions) is commonly observed in schizophrenia, but very little is known about its correlates. It is found that schizophrenia-related emotional difficulties tend to emerge in the context when cognitive demands are increased. The prevalence of alexithymia is also high in alcoholic patients, i.e., between 40% and 60%, and predicted a poor prognosis in these patients. Limited evidence exists regarding the association of alexithymia with alcohol consumption and severity of alcohol dependence and level of alexithymia in dual diagnosis.
The present study showed significantly higher prevalence and severity of alexithymia in schizophrenia patients with alcohol use compared to those without alcohol use. It can be well explained as both the disorders are individually associated with significant levels of alexithymia and dual diagnosis may further aggravate the ability to understand or express one's emotions and overall alexithymia.
In the present study, alexithymia was significantly associated with negative symptoms score on PANSS. Some authors found similar results, that is, nonparanoid schizophrenia patients with predominant negative symptoms were more commonly identified as alexithymic compared to others. Furthermore, Van't Wout et al. found that negative symptoms were correlated with deficits in identifying the feelings. Some other authors found no relation of alexithymia with the negative symptoms and suggested that it is a separate and independent construct from schizophrenia.
The scatter diagram [Figure 1] depicting the correlation between cognitive impairment and alexithymia showed that lesser the score on MoCA (poor cognition), higher is the score on TAS-20 (more alexithymia).
Neurobiological research suggests that alexithymia patients have impaired inter-hemispheric communication and may have dysfunctional/deficient brain structures or circuits.,, In the general population, higher alexithymia has been found to be associated with poorer performance in neurocognitive tests. Research on metacognition (the ability to form complex representations of oneself and others) found that alexithymia in schizophrenia is related to impaired verbal memory, processing speed as well as executive functioning. Greater alexithymia was also found to be significantly associated with impaired cognitive domains in asymptomatic HIV patients. Impairment in working memory was also found in those who lack the ability to distinguish their own thoughts and feelings. Thus, patients having more significant cognitive impairment were more likely to have alexithymia and had positive correlation with the severity.
Another study conducted on 65 adults with schizophrenia spectrum disorders using TAS-20, and MATRICS battery (for neuro-cognition) revealed that DIF and EOT were linked with greater levels of neurocognitive deficits compared to DDF.
Thus, this study is one of the few studies assessing the cognition and alexithymia in schizophrenia patients and those with comorbid alcohol use along with finding the relationship between cognitive deficits and alexithymia.
| Conclusion|| |
Cognitive impairment and alexithymia are common associations in schizophrenia but when comorbid alcohol use is present, both the symptoms aggravate. Cognitive dysfunction (overall cognitive dysfunction based on MoCA score) and alexithymia were significantly more in patients of schizophrenia with comorbid alcohol use and positively correlated with the severity of alcohol use. Cognitive impairment could also be correlated to alexithymia, and poorer the cognition more prevalent was the alexithymia. It is important to assess these aspects as they may affect the recovery and long-term prognosis in patients with the dual diagnosis of schizophrenia and alcohol use disorder. Assessment and early intervention can be helpful for the better outcome.
This was a cross-sectional, single-center-based study with smaller sample size. Large sample and multi-centered prospective study may yield better results. Individual components of cognition were not studied which would have helped in finding which cognitive functions are affected significantly in the study participants.
We wish to thank all the patients and their family members who participated, cooperated and agreed for the publication of data.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]