ABSTRACT
Introduction: Among the executive functions affected in attention deficit hyperactivity disorder (ADHD), inhibitory control is one of the primary areas of impairment, characterized by components that include response inhibition and interference control. Determining the impaired inhibitory control components will be useful in the differential diagnosis and treatment of ADHD. The present study aimed to investigate response inhibition and interference control abilities of adults with ADHD. Methods: The study included 42 adults diagnosed with ADHD and 43 healthy controls. The stop-signal task (SST) and Stroop test were used for assessing the response inhibition and interference control, respectively. Multivariate analysis of covariance was used for comparing the ADHD and healthy control groups in terms of their SST and Stroop test scores, wherein the age and education level of the participants were taken as covariables. The relationship between SST and Stroop Test and Barratt Impulsiveness Scale-11 (BIS-11) was tested by Pearson correlation analysis. Mann-Whitney U test was used for comparing the test scores between those who were administered with psychostimulants among the adults with ADHD and those who were not. Results: Response inhibition was observed to be impaired in adults with ADHD compared with the healthy controls, whereas no difference regarding interference control was observed. As per the Barratt Impulsiveness Scale-11 (BIS-11), a weak and moderately negative relationship was found between the stop signal delay and the attentional, motor, non-planning scores, and total scores and a weak positive relationship was found between the stop-signal reaction time and the attentional, motor, non-planning scores, and total scores. A significant improvement was observed in the response inhibition skills of the adults with ADHD who had received methylphenidate treatment compared to those who had not, and the former also showed lower impulsivity levels as measured by the BIS-11. Conclusions: It should be noted that response inhibition and interference control, which are considered under the umbrella of inhibitory control, may exhibit different characteristics in adult individuals diagnosed with ADHD and this is important for differential diagnosis. An improvement was observed in the response inhibition of adults with ADHD caused by psychostimulant treatment, which was associated with positive outcomes that were also noticeable by the patients. Understanding the underlying neurophysiological mechanisms of the condition would further facilitate the development of appropriate treatments.
ABSTRACT
Introduction: Quality of life (QoL) is a concept defined as a subjective perception of one's position in life and is negatively affected in many psychiatric illnesses such as bipolar disorder (BD) and schizophrenia (SCZ). It is hypothesized that therapeutic approaches based on QoL can increase the patient's adherence to treatment and contribute to a satisfactory life. This study aimed to compare the QoL of individuals having BD and schizophrenia with that of healthy controls (HCs) and to investigate the impact of the state of remission on QoL. Method: The World Health Organization QoL Scale-Short Form (WHOQOL-Bref) was administered to individuals with BD (n=124) and SCZ (n=74) and to HCs (n=81) to evaluate QoL. The WHOQOL-Bref subscale and total scores were compared between the groups using multifactor analysis of covariance (MANCOVA) by considering age and education level as the covariates. Then, the patient groups were compared using MANCOVA based on the state of remission by taking age, level of education, and Global Assessment of Functioning scores as the covariates. The relationship between clinical features and QoL scores was evaluated using correlation analysis, and linear regression analysis was applied for the variables that were found to be significant. Results: It was found that individuals with SCZ or BD had lower WHOQOL-Bref psychological, social, and total scores than HCs. Those with SCZ additionally had lower physical and environmental subscale scores than HCs. Furthermore, those with SCZ had lower WHOQOL-Bref physical, psychological, social, and total scores than individuals with BD. There was no significant difference in WHOQOL-Bref scores between individuals with BD and SCZ in the remission period. WHOQOL-Bref physical, psychological, and total scores were found to be significantly lower in unremitted BD patients when compared with remitted BD patients. Unremitted BD patients were found to have significantly lower WHOQOL-Bref psychological, environmental, and total scale scores than unremitted SCZ patients. Conclusion: It can be concluded that the QoL of individuals with BD is between that of healthy individuals and those with SCZ. However, unremitted BD patients have lower QoL than unremitted SCZ patients. Both patient groups display similar features during remission. Identifying the similarities and differences in terms of QoL in both patient groups is of great importance to develop the best type of treatment for the patients.
ABSTRACT
INTRODUCTION: Bipolar disorder (BD) and attention deficit hyperactivity disorder (ADHD) often co-occur in adult population. Both conditions present various neurocognitive and behavioral problems. We aimed to examine neurocognitive functions in adult patients with comorbid BD and ADHD (BD+ADHD) in comparison to patients with only BD, only ADHD and healthy controls (HCs). METHOD: An extensive cognitive battery which evaluates verbal learning and memory, visual memory, processing speed, attention, executive functions, working memory and verbal fluency, was used to assess neurocognitive functions respectively in adult (age 18-65 years) patients with BD (n=37), ADHD (n=43), BD+ADHD (n=20) in comparison to HCs (n=51). The Multivariate Analysis of Covariance models, where age, level of education and total BIS-11 scores were included as covariates, were used for comparing neurocognitive scores among groups. RESULTS: Both BD and BD+ADHD groups showed significantly poorer performance than HCs in processing speed, attention, executive functions, and verbal fluency domains. The BD group had additional significant deficits in executive functions, verbal learning and memory domains. There were no significant differences between BD and BD+ADHD groups with regards to verbal learning and memory, visual memory, processing speed, attention, executive functions, working memory and verbal fluency domains. Patients with only ADHD showed significantly poorer performance than HCs in verbal fluency domain. CONCLUSIONS: Our results show similarities in the neurocognitive functions of adults with BD and BD+ADHD across a wide range of cognitive domains. The findings point to the need for further exploration of diverging and converging neurodevelopmental trajectories of BD and ADHD.