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Featured researches published by Nadeem Kalak.


Journal of Psychiatric Research | 2012

Facing depression with botulinum toxin: A randomized controlled trial

M. Axel Wollmer; Claas de Boer; Nadeem Kalak; Johannes Beck; Thomas Götz; Tina Schmidt; Muris Hodzic; Ursula Bayer; Thilo Kollmann; Katja Kollewe; Daniela Sönmez; Katja Duntsch; Martin D. Haug; Manfred Schedlowski; Martin Hatzinger; Dirk Dressler; Serge Brand; Edith Holsboer-Trachsler; Tillmann H.C. Kruger

Positive effects on mood have been observed in subjects who underwent treatment of glabellar frown lines with botulinum toxin and, in an open case series, depression remitted or improved after such treatment. Using a randomized double-blind placebo-controlled trial design we assessed botulinum toxin injection to the glabellar region as an adjunctive treatment of major depression. Thirty patients were randomly assigned to a verum (onabotulinumtoxinA, n = 15) or placebo (saline, n = 15) group. The primary end point was change in the 17-item version of the Hamilton Depression Rating Scale six weeks after treatment compared to baseline. The verum and the placebo groups did not differ significantly in any of the collected baseline characteristics. Throughout the sixteen-week follow-up period there was a significant improvement in depressive symptoms in the verum group compared to the placebo group as measured by the Hamilton Depression Rating Scale (F((6,168)) = 5.76, p < 0.001, η(2) = 0.17). Six weeks after a single treatment scores of onabotulinumtoxinA recipients were reduced on average by 47.1% and by 9.2% in placebo-treated participants (F((1,28)) = 12.30, p = 0.002, η(2) = 0.31, d = 1.28). The effect size was even larger at the end of the study (d = 1.80). Treatment-dependent clinical improvement was also reflected in the Beck Depression Inventory, and in the Clinical Global Impressions Scale. This study shows that a single treatment of the glabellar region with botulinum toxin may shortly accomplish a strong and sustained alleviation of depression in patients, who did not improve sufficiently on previous medication. It supports the concept, that the facial musculature not only expresses, but also regulates mood states.


Journal of Adolescent Health | 2012

Daily Morning Running for 3 Weeks Improved Sleep and Psychological Functioning in Healthy Adolescents Compared With Controls

Nadeem Kalak; Markus Gerber; Roumen Kirov; Thorsten Mikoteit; Juliana Yordanova; Uwe Pühse; Edith Holsboer-Trachsler; Serge Brand

PURPOSE To compare sleep electroencephalographic patterns and psychological functioning of healthy adolescents running regularly in the mornings with those of control subjects. Although several studies have shown that regular moderate-to-vigorous exercise is related to favorable sleep and psychological functioning in adolescents, research on the effectiveness of short interventions is more limited. METHODS Fifty-one adolescents (mean age = 18.30 years; 27 female [53%]) took part in the study; they were randomly assigned either to a running or to a control group. The running group went running every morning for 30 minutes at moderate intensity during weekdays for 3 consecutive weeks. Sleep electroencephalographic patterns and psychological functioning were assessed in both groups before and after the 3-week period. All participants also kept a sleep log for 3 weeks. RESULTS Objective sleep improved (slow-wave sleep increased; sleep onset latency decreased) in the running group compared with the control group. Subjective sleep quality, mood, and concentration during the day improved, whereas sleepiness during the day decreased. CONCLUSIONS Thirty minutes of running in the morning during weekdays for 3 consecutive weeks impacted positively on sleep and psychological functioning in healthy adolescents compared with control subjects. Running is inexpensive and easy to implement during school schedules, and as both objective and subjective improvements were observed within 3 weeks, regular physical exercise should be promoted.


Stress and Health | 2013

Are Adolescents With High Mental Toughness Levels More Resilient Against Stress

Markus Gerber; Nadeem Kalak; Sakari Lemola; Peter J. Clough; John L. Perry; Uwe Pühse; Catherine Elliot; Edith Holsboer-Trachsler; Serge Brand

Mental toughness has been explored predominantly within sport contexts. Nevertheless, it is difficult to conceive mental toughness as only applicable to athletes. This study examines whether mentally tough participants exhibit resilience against stress. This is a cross-sectional study based on two different samples: Sample 1 consisted of 284 high school students (99 males, 185 females, M = 18.3 years). Sample 2 consisted of 140 first through fifth semester undergraduate students (53 males, 87 females, M = 20.0 years). Participants provided information about their level of perceived stress (10-item Perceived Stress Scale), mental toughness (48-item Mental Toughness Questionnaire) and depressive symptoms (Beck Depression Inventory). Consistent across the two samples, mental toughness mitigated the relationship between high stress and depressive symptoms. The interaction between stress and mental toughness explained 2% of variance in the adolescent sample and 10% of variance among young adults. The promotion of protective factors that foster resilient adaptation is a relevant issue. Mental toughness may appeal to individuals that are typically difficult to be reached with health interventions. Because mental toughness is part of young peoples daily speech, it may serve as a less academic resource than other health psychology concepts.


Journal of Adolescent Health | 2014

Adolescents With Greater Mental Toughness Show Higher Sleep Efficiency, More Deep Sleep and Fewer Awakenings After Sleep Onset

Serge Brand; Markus Gerber; Nadeem Kalak; Roumen Kirov; Sakari Lemola; Peter J. Clough; Uwe Pühse; Edith Holsboer-Trachsler

PURPOSE Mental toughness (MT) is understood as the display of confidence, commitment, challenge, and control. Mental toughness is associated with resilience against stress. However, research has not yet focused on the relation between MT and objective sleep. The aim of the present study was therefore to explore the extent to which greater MT is associated with objectively assessed sleep among adolescents. METHODS A total of 92 adolescents (35% females; mean age, 18.92 years) completed the Mental Toughness Questionnaire. Participants were split into groups of high and low mental toughness. Objective sleep was recorded via sleep electroencephalograms and subjective sleep was assessed via a questionnaire. RESULTS Compared with participants with low MT, participants with high MT had higher sleep efficiency, a lower number of awakenings after sleep onset, less light sleep, and more deep sleep. They also reported lower daytime sleepiness. CONCLUSIONS Adolescents reporting higher MT also had objectively better sleep, as recorded via sleep electroencephalograms. A bidirectional association between MT and sleep seems likely; therefore, among adolescence, improving sleep should increase MT, and improving MT should increase sleep.


Sleep Medicine | 2014

High self-perceived exercise exertion before bedtime is associated with greater objectively assessed sleep efficiency

Serge Brand; Nadeem Kalak; Markus Gerber; Roumen Kirov; Uwe Pühse; Edith Holsboer-Trachsler

OBJECTIVE To assess the association between self-perceived exercise exertion before bedtime and objectively measured sleep. METHODS Fifty-two regularly exercising young adults (mean age, 19.70 years; 54% females) underwent sleep electroencephalographic recordings 1.5 h after completing moderate to vigorous exercise in the evening. Before sleeping, participants answered questions regarding degree of exertion of the exercise undertaken. RESULTS Greater self-perceived exertion before bedtime was associated with higher objectively assessed sleep efficiency (r = 0.69, P <0.001); self-perceived exertion explained 48% of the variance in sleep efficiency (R2 = 0.48). Moreover, high self-perceived exercise exertion was associated with more deep sleep, shortened sleep onset time, fewer awakenings after sleep onset, and shorter wake duration after sleep onset. Multiple linear regression analysis showed that objective sleep efficiency was predicted by increased exercise exertion, shortened sleep onset time, increased deep sleep, and decreased light sleep. CONCLUSION Against expectations and general recommendations for sleep hygiene, high self-perceived exercise exertion before bedtime was associated with better sleep patterns in a sample of healthy young adults. Further studies should also focus on elderly adults and adults suffering from insomnia.


Neuropsychobiology | 2013

Both Hair Cortisol Levels and Perceived Stress Predict Increased Symptoms of Depression: An Exploratory Study in Young Adults

Markus Gerber; Nadeem Kalak; Catherine Elliot; Edith Holsboer-Trachsler; Uwe Pühse; Serge Brand

Objective: Depressive symptoms are a common mental health problem among young adults, but the physiological mechanisms that mediate between stress and depressive symptoms remain unclear. Accordingly, this exploratory study (1) examined how hair cortisol concentrations were associated with self-perceived stress and depressive symptoms in a sample of young adults and (2) tested whether hair cortisol could explain variance in depressive symptoms beyond perceived stress before and after controlling for levels of vigorous physical activity (VPA). Methods: The sample consisted of 42 exercise and health science university students (20 males, 22 females; mean age = 21.2 years). Cortisol concentrations were extracted from hair strands close to the scalp. Participants completed self-rating questionnaires about depressive symptoms and perceived stress. Results: Students with elevated hair cortisol levels tended to report lower depressive symptoms and lower perceived stress. Increased perceived stress was associated with higher depressive symptoms, and both hair cortisol and perceived stress predicted depressive symptoms after controlling for VPA. Conclusions: The present data suggest that elevated hair cortisol levels do not necessarily constitute a health risk. Hair cortisol measurement can serve as a noninvasive and painless biomarker of chronic stress and mental disorders; however, additional research is needed.


Journal of Adolescent Health | 2011

Dream recall and its relationship to sleep, perceived stress, and creativity among adolescents

Serge Brand; Johannes Beck; Nadeem Kalak; Markus Gerber; Roumen Kirov; Uwe Pühse; Martin Hatzinger; Edith Holsboer-Trachsler

PURPOSE To explore associations between dream recall, gender, sleep, perceived stress, and creativity in a large sample of adolescents. In adults, women report a higher frequency of dream recall than men. Moreover, increased awakenings seem to increase dream recall, whereas low sleep quality is associated with low dream recall. In addition, there is some evidence that dream recall is associated with personality traits such as creativity. For adolescents, comparable data from larger samples are missing to date. METHOD A total of 5,580 adolescents (mean age: 18.23 years; 3,711 females and 1,869 males) participated in the present study. Participants completed an Internet-administered questionnaire related to dreaming, sleep, perceived stress, and creativity. RESULTS As compared with males, female adolescents reported a higher dream recall rate and felt a stronger impact of dreams on the subsequent day. Female adolescents also described themselves as more creative, and reported suffering more from sleep complaints and perceived stress. Multiple regression analyses further revealed that increased dream recall was independently predicted by factors such as female gender, sleep quality, and creativity, whereas perceived stress, awakenings during the night, and sleep duration had no predictive value. CONCLUSIONS Similar to the findings of studies conducted on adults, dream recall was also associated with female gender in a large sample of adolescents. Additionally, it seemed that several different factors such as good mood, increased sleep quality, and creativity influenced dream recall. These results can provide a basis for better understanding the psychology of dreams in adolescence. In contrast to nightmares, recalling dreaming is associated with health and well-being.


Sleep Medicine Reviews | 2016

The relationship between physical activity and sleep from mid adolescence to early adulthood. A systematic review of methodological approaches and meta-analysis.

Christin Lang; Nadeem Kalak; Serge Brand; Edith Holsboer-Trachsler; Uwe Pühse; Markus Gerber

Physical activity (PA) is considered an effective, non-pharmacological approach to improve sleep. However, the accurate measurement of PA and sleep among adolescents is fraught with challenges. Additionally, comparing the results of different studies is often difficult due to the diversity of assessment tools, analyses and data reporting procedures used. While previous reviews have considered variables that may confound this relationship, this systematic review examines the variations in measurement methods. Based on this overview, a meta-analysis was performed to assess possible influences of the various approaches on effect sizes. Twenty-one studies were included in the systematic review, of which 12 were appropriate for meta-analysis. For this, four subgroups were formed: subjective PA and subjective sleep, objective PA and subjective sleep, subjective PA and objective sleep, and objective PA and objective sleep. The majority of studies used subjective measures, often with unknown reliability or validity. Few studies employed objective tools to measure sleep. The results suggest that adolescents with higher subjective and objective PA are more likely to experience good sleep subjectively and objectively. More studies employing subjective and objective measures for both PA and sleep are needed. Researchers should take into account several assessment factors unique to the adolescent population.


Journal of Health Psychology | 2016

During early and mid-adolescence, greater mental toughness is related to increased sleep quality and quality of life

Serge Brand; Nadeem Kalak; Markus Gerber; Peter J. Clough; Sakari Lemola; Uwe Pühse; Edith Holsboer-Trachsler

The aim of this study was to explore the association between mental toughness, subjective sleep, physical activity, and quality of life during early and mid-adolescence. A total of 1475 participants (mean age = 13.4 years; range: 11–16 years) took part in the study. They completed questionnaires related to mental toughness, physical activity, subjective sleep, and quality of life. Greater mental toughness was related to more favorable quality of life and increased subjective sleep. Mental toughness was not related to physical activity. Increased mental toughness, favorable quality of life, and sleep are related during early and mid-adolescence. Against our expectations, mental toughness was not related to physical activity.


Frontiers in Psychiatry | 2014

Agitation Predicts Response of Depression to Botulinum Toxin Treatment in a Randomized Controlled Trial

M. Axel Wollmer; Nadeem Kalak; Stefanie Jung; Claas de Boer; Michelle Magid; Jason S. Reichenberg; Serge Brand; Edith Holsboer-Trachsler; Tillmann H.C. Kruger

In a randomized, controlled trial (n = 30), we showed that botulinum toxin injection to the glabellar region produces a marked improvement in the symptoms of major depression. We hypothesized that the mood-lifting effect was mediated by facial feedback mechanisms. Here we assessed if agitation, which may be associated with increased dynamic psychomotor activity of the facial musculature, can predict response to the treatment. To test this hypothesis, we re-analyzed the data of the scales from our previous study on a single item basis and compared the baseline scores in the agitation item (item 9) of the Hamilton Depression Rating Scale (HAM-D) between responders (n = 9) and participants who did not attain response (n = 6) among the recipients of onabotulinumtoxinA (n = 15). Responders had significantly higher item 9 scores at baseline [1.56 + 0.88 vs. 0.33 + 0.52, t(13) = 3.04, d = 1.7, p = 0.01], while no other single item of the HAM-D or the Beck Depression Inventory was associated with treatment response. The agitation score had an overall precision of 78% in predicting response in a receiver operating characteristic (ROC) analysis (area under the curve, AUC = 0.87). These data provide a link between response to botulinum toxin treatment with a psychomotor manifestation of depression and thereby indirect support of the proposed facial feedback mechanism of action. Moreover, it suggests that patients with agitated depression may particularly benefit from botulinum toxin treatment.

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Peter J. Clough

Manchester Metropolitan University

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Roumen Kirov

Bulgarian Academy of Sciences

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