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Featured researches published by Philipp Ritter.


International Journal of Bipolar Disorders | 2014

Lithium for prevention of mood episodes in bipolar disorders: systematic review and meta-analysis

Emanuel Severus; Matthew Taylor; Cathrin Sauer; Andrea Pfennig; Philipp Ritter; Michael Bauer; John Geddes

BackgroundIn a previous meta-analysis of randomized controlled trials comparing lithium with placebo as a long-term treatment in bipolar disorders, we observed a clear preventative effect for manic episodes; however, the effect was equivocal for depressive episodes. Since then, the evidence base has grown further. In this update, we furthermore present the data on efficacy of lithium in comparison to alternative drug treatments. In addition, we analyze the data comparing lithium with placebo and other treatments regarding drop-outs due to reasons other than a mood episode and completion of study (no mood episode and no drop-out to reasons other than a mood episode).MethodsRandomized controlled trials (RCTs) were sought comparing lithium with placebo and lithium with an alternative treatment in bipolar disorders where the stated intent of treatment was prevention of mood episodes. To this purpose, the Cochrane Central Register of Controlled Trials (CENTRAL) was searched. Reference lists of relevant papers and major textbooks of mood disorders were examined. Authors, other experts in the field, and pharmaceutical companies were contacted for knowledge of suitable trials, published or unpublished.ResultsFor the comparison of lithium with placebo, seven trials (1,580 participants) were included. Lithium was more effective than placebo in preventing overall mood episodes (random effects RR 0.66, 95% CI 0.53 to 0.82), manic episodes (random effects RR 0.52, 95% CI 0.38 to 0.71), and, dependent on the type of analyses applied, depressive episodes (random effects RR 0.78, 95% CI 0.59 to 1.03; fixed effect RR 0.73, 95% CI 0.60 to 0.88). Lithium was inferior to placebo in leading to drop-outs for reasons other than a mood episode (random effects RR 1.33, 95% CI 1.07 to 1.65) but superior to placebo on study completion (random effects RR 1.69, 95% CI 1.12 to 2.55).For the comparison of lithium with anticonvulsants, seven trials were included (n = 1,305). In prevention of manic episodes, lithium showed superiority compared to anticonvulsants (random effects RR 0.66, 95% CI 0.44 to 1.00). However, there was no significant difference regarding prevention of overall mood episodes, depressive episodes, dropping-out to reasons other than a mood episode, or study completion.ConclusionsThe evidence base for lithium in the long-term treatment of bipolar disorders has strengthened. With no other drug available having such ample and consistent evidence for its efficacy lithium remains the most valuable treatment option in this indication.


Journal of Affective Disorders | 2012

Risk constellations prior to the development of bipolar disorders: Rationale of a new risk assessment tool

Karolina Leopold; Philipp Ritter; Christoph U. Correll; Carolin Marx; Seza Özgürdal; Georg Juckel; Michael Bauer; Andrea Pfennig

BACKGROUND The precise characterisation of a high risk status for the development of a psychiatric disorder and the question of how well this predicts disease manifestation is of major importance as negative consequences of late diagnosis and treatment have been well demonstrated. In the absence of well defined and disease specific biological markers for bipolar disorder, the recognition of premature stages must rely on combinations of risk factors that have been associated with later disease manifestation. METHODS A review of the literature and our experience from the Early Recognition Centre led us to identify symptom constellations. RESULTS Individual categories defined and grouped included: (I) genetic risk, (II) substance use, misuse or dependence, (III) diagnosis/suspected diagnosis of attention deficit hyperactivity disorder, (IV) pronounced creativity, (V) impairment in psychosocial functioning, (VI) subthreshold affective symptoms, and (VII) early symptomatology including (a) changes in sleep and circadian rhythm, (b) changes in mood, mood swings/affective lability, (c) fearfulness/anxiety, and (d) dissociative symptoms. These risk constellations were operationalised and a new risk assessment instrument, the Early Phase Inventory for Bipolar Disorders (EPIbipolar) was developed. LIMITATIONS Challenges regarding the validity of the data on which the instrument is based, specificity of and correlations between risk categories, and ethical considerations were encountered. CONCLUSIONS Further use of EPIbipolar in research should help to refine prodromal features and narrow these down to a less cumbersome core that can be used to develop a shortened tool for use in clinical care. Prospective longitudinal research is needed to establish the predictive validity of this novel bipolar disorder risk assessment tool.


Journal of Neural Transmission | 2012

The characteristics of sleep in patients with manifest bipolar disorder, subjects at high risk of developing the disease and healthy controls

Philipp Ritter; Carolin Marx; Natalia Lewtschenko; Steffi Pfeiffer; Karolina Leopold; Michael Bauer; Andrea Pfennig

Sleep is highly altered during affective episodes in patients with bipolar disorder. There is accumulating evidence that sleep is also altered in euthymic states. A deficit in sleep regulation may be a vulnerability factor with aetiological relevance in the development of the disease. This study aims to explore the objective, subjective and lifetime sleep characteristics of patients with manifest bipolar disorder and persons with an elevated risk of developing the disease. Twenty-two patients with bipolar I and II disorder, nine persons with an elevated risk of developing the disorder and 28 healthy controls were evaluated with a structured interview to characterize subjective and lifetime sleeping habits. In addition, participants wore an actimeter for six nights. Patients with bipolar disorder had longer sleep latency and duration compared with healthy controls as determined by actigraphy. The subjective and lifetime sleep characteristics of bipolar patients differed significantly from healthy controls. The results of participants with an elevated risk of developing the disorder had subjective and lifetime characteristics that were largely analogous to those of patients with manifest bipolar disorder. In particular, both groups described recurring insomnia and hypersomnia, sensitivity to shifts in circadian rhythm, difficulties awakening and prolonged sleep latency. This study provides further evidence that sleep and circadian timing are profoundly altered in patients with bipolar disorder. It may also tentatively suggest that sleep may be altered prior to the first manic episode in subjects at high risk.


International Journal of Bipolar Disorders | 2015

The suicide prevention effect of lithium: more than 20 years of evidence—a narrative review

Ute Lewitzka; Emanuel Severus; Rita Bauer; Philipp Ritter; Bruno Müller-Oerlinghausen; Michael Bauer

The management and treatment of patients with suicidal behavior is one of the most challenging tasks for health-care professionals. Patients with affective disorders are at high risk for suicidal behavior, therefore, should be a target for prevention. Numerous international studies of lithium use have documented anti-suicidal effects since the 1970s. Despite the unambiguous evidence of lithium’s anti-suicidal effects and recommendations in national and international guidelines for its use in acute and maintenance therapy of affective disorders, the use of lithium is still underrepresented. The following article provides a comprehensive review of studies investigating the anti-suicidal effect of lithium in patients with affective disorders.


Bipolar Disorders | 2011

The role of disturbed sleep in the early recognition of bipolar disorder: a systematic review

Philipp Ritter; Carolin Marx; Michael Bauer; Karolina Lepold; Andrea Pfennig

Ritter PS, Marx C, Bauer M, Lepold K, Pfennig A. The role of disturbed sleep in the early recognition of bipolar disorder: a systematic review.
Bipolar Disord 2011: 13: 227–237.


Bipolar Disorders | 2012

Treatment options for acute depression in bipolar disorder.

Michael Bauer; Philipp Ritter; Heinz Grunze; Andrea Pfennig

Bauer M, Ritter P, Grunze H, Pfennig A. Treatment options for acute depression in bipolar disorder. Bipolar Disord 2012: 14 (Suppl. 2): 37–50.


Journal of Affective Disorders | 2014

Relationship between sunlight and the age of onset of bipolar disorder: an international multisite study.

Michael Bauer; Tasha Glenn; Martin Alda; Ole A. Andreassen; Elias Angelopoulos; Raffaella Ardau; Christopher Baethge; Rita Bauer; Frank Bellivier; R.H. Belmaker; Michael Berk; Thomas Bjella; Letizia Bossini; Yuly Bersudsky; Eric Yat Wo Cheung; Jörn Conell; Maria Del Zompo; Seetal Dodd; Bruno Etain; Andrea Fagiolini; Mark A. Frye; Kostas N. Fountoulakis; Jade Garneau-Fournier; Ana González-Pinto; Hirohiko Harima; Stefanie Hassel; Chantal Henry; Apostolos Iacovides; Erkki Isometsä; Flávio Kapczinski

BACKGROUND The onset of bipolar disorder is influenced by the interaction of genetic and environmental factors. We previously found that a large increase in sunlight in springtime was associated with a lower age of onset. This study extends this analysis with more collection sites at diverse locations, and includes family history and polarity of first episode. METHODS Data from 4037 patients with bipolar I disorder were collected at 36 collection sites in 23 countries at latitudes spanning 3.2 north (N) to 63.4 N and 38.2 south (S) of the equator. The age of onset of the first episode, onset location, family history of mood disorders, and polarity of first episode were obtained retrospectively, from patient records and/or direct interview. Solar insolation data were obtained for the onset locations. RESULTS There was a large, significant inverse relationship between maximum monthly increase in solar insolation and age of onset, controlling for the country median age and the birth cohort. The effect was reduced by half if there was no family history. The maximum monthly increase in solar insolation occurred in springtime. The effect was one-third smaller for initial episodes of mania than depression. The largest maximum monthly increase in solar insolation occurred in northern latitudes such as Oslo, Norway, and warm and dry areas such as Los Angeles, California. LIMITATIONS Recall bias for onset and family history data. CONCLUSIONS A large springtime increase in sunlight may have an important influence on the onset of bipolar disorder, especially in those with a family history of mood disorders.


Journal of Psychiatric Research | 2015

Disturbed sleep as risk factor for the subsequent onset of bipolar disorder – Data from a 10-year prospective-longitudinal study among adolescents and young adults

Philipp Ritter; Michael Höfler; Hans-Ulrich Wittchen; Roselind Lieb; Michael Bauer; Andrea Pfennig; Katja Beesdo-Baum

There is ample data suggesting that individuals with bipolar disorder more frequently suffer from disturbed sleep even when euthymic. Since sleep is a process that is crucial for affective homeostasis, disturbed sleep in healthy individuals may be a risk factor for the subsequent onset of bipolar disorder. Utilizing data from a large cohort of adolescents and young adults, this study tests the hypothesis that disturbed sleep constitutes a risk factor for the later onset of bipolar disorder. A representative community sample of N = 3021 adolescents and young adults (baseline age 14-24) was assessed using the standardized Composite International Diagnostic Interview and followed-up prospectively up to 3 times over up to 10 years. Disturbed sleep at baseline was quantified utilizing the corresponding items from the self-report inventory SCL-90-R. The compound value (insomnia-score) as an ordinal parameter for the severity of sleep disturbances was used to assess associations with the incidence of bipolar disorder among participants free of major mental disorder at baseline (N = 1943) using odds ratios (OR) from logistic regressions. Analyses were adjusted for age, gender, parental mood disorder and lifetime alcohol or cannabis dependence. Poor sleep quality significantly increased the risk for the subsequent development of bipolar disorder (OR = 1.75; p = 0.001). Regarding individual sleep items, trouble falling asleep and early morning awakening were predictive for the subsequent onset of bipolar disorder. Disturbed sleep in persons otherwise free of major mental disorders appears to confer an increased risk for the subsequent onset of bipolar disorder.


Journal of Psychiatric Research | 2015

Influence of light exposure during early life on the age of onset of bipolar disorder

Michael Bauer; Tasha Glenn; Martin Alda; Ole A. Andreassen; Elias Angelopoulos; Raffaella Ardau; Christopher Baethge; Rita Bauer; Bernhard T. Baune; Frank Bellivier; R.H. Belmaker; Michael Berk; Thomas Bjella; Letizia Bossini; Yuly Bersudsky; Eric Yat Wo Cheung; Jörn Conell; Maria Del Zompo; Seetal Dodd; Bruno Etain; Andrea Fagiolini; Mark A. Frye; Kostas N. Fountoulakis; Jade Garneau-Fournier; Ana González-Pinto; John F. Gottlieb; Hirohiko Harima; Stefanie Hassel; Chantal Henry; Apostolos Iacovides

BACKGROUND Environmental conditions early in life may imprint the circadian system and influence response to environmental signals later in life. We previously determined that a large springtime increase in solar insolation at the onset location was associated with a younger age of onset of bipolar disorder, especially with a family history of mood disorders. This study investigated whether the hours of daylight at the birth location affected this association. METHODS Data collected previously at 36 collection sites from 23 countries were available for 3896 patients with bipolar I disorder, born between latitudes of 1.4 N and 70.7 N, and 1.2 S and 41.3 S. Hours of daylight variables for the birth location were added to a base model to assess the relation between the age of onset and solar insolation. RESULTS More hours of daylight at the birth location during early life was associated with an older age of onset, suggesting reduced vulnerability to the future circadian challenge of the springtime increase in solar insolation at the onset location. Addition of the minimum of the average monthly hours of daylight during the first 3 months of life improved the base model, with a significant positive relationship to age of onset. Coefficients for all other variables remained stable, significant and consistent with the base model. CONCLUSIONS Light exposure during early life may have important consequences for those who are susceptible to bipolar disorder, especially at latitudes with little natural light in winter. This study indirectly supports the concept that early life exposure to light may affect the long term adaptability to respond to a circadian challenge later in life.


International Journal of Bipolar Disorders | 2013

Drug treatment patterns in bipolar disorder: analysis of long-term self-reported data

Michael Bauer; Tasha Glenn; Martin Alda; Kemal Sagduyu; Wendy K. Marsh; Paul Grof; Rodrigo A. Munoz; Emanuel Severus; Philipp Ritter; Peter C. Whybrow

BackgroundThe objective of this study is to investigate drug treatment patterns in bipolar disorder using daily data from patients who received treatment as usual.MethodsPatients self-reported the drugs taken daily for about 6 months. Daily drug use and drug combinations were determined for each patient, both by the specific drugs and by medication class. The drug load was calculated for all drugs taken within a medication class.Results and discussionFour hundred fifty patients returned a total of 99,895 days of data (mean 222.0 days). The most frequently taken drugs were mood stabilizers. Of the 450 patients, 353 (78.4%) took a stable drug combination for ≥50% of days. The majority of patients were taking polypharmacy, including 75% of those with a stable combination. Only a small number of drugs were commonly taken within each medication class, but there were a large number of unique drug combinations: 52 by medication class and 231 by specific drugs. Eighty percent of patients with a stable combination were taking three or less drugs daily. Patients without a stable combination took drugs but made frequent changes. Taking more than one drug within a medication class greatly increased the drug load.To summarize, (1) patients were more likely to take a mood stabilizer than any other drug; (2) although most patients were taking polypharmacy, there were no predominant drug regimens even among those taking a stable combination; and (3) most patients with a stable combination take a relatively small number of drugs daily. The wide variation in drug regimens and numerous possible drug combinations suggest that more evidence is needed to optimize treatment of bipolar disorder.

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Michael Bauer

Dresden University of Technology

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Andrea Pfennig

Dresden University of Technology

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Emanuel Severus

Dresden University of Technology

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Jörn Conell

Dresden University of Technology

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Rita Bauer

Dresden University of Technology

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Paul Grof

University of Toronto

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