Use of polypharmacy and self-reported mood in outpatients with bipolar disorder

Objective. As polypharmacy is routinely used for the treatment of bipolar disorder, the relation between the daily number of psychotropic medications and self-reported mood was investigated. Method. Eighty patients (35 men and 45 women) with a diagnosis of bipolar disorder I or II, recruited from academic centres, entered their mood, sleep, and psychotropic medications for 3 months into ChronoRecord software. A total of 8662 days of data was received (mean 114.7 days/per patient). Results. Seventy-nine patients took a mean of 3.8 medications daily (SD 1.7; range 1-9); one took none. Of these patients, 73 (92.4%) took mood stabilizers, 47 (58.8%) took antidepressants, 31 (38.8%) took antipsychotics, 34 (42.5%) took benzodiazepines and 17 (21.1%) took thyroid hormones. Patients reporting normal mood more frequently took fewer medications; the Pearson correlation coefficient between the number of medications and the percent of days normal was -0.481 (P < 0.001). Grouping by number of medications, ANOVA analysis showed those taking fewer medications reported normal mood more frequently (P<0.001). Conclusion. Combination treatment regimens are routinely prescribed for bipolar disorder. Patients reporting normal mood more frequently took a fewer number of daily medications. Studies are needed to better identify those patients who would benefit from polypharmacy and to optimise the combinations of medications for patients with refractory disorder.

A pilot study of visual backward masking performance among affected versus unaffected offspring of parents with bipolar disorder

BACKGROUND

Cognitive dysfunction is evident in some euthymic patients with established bipolar disorder (BD), including deficits in visual backward masking (VBM) tasks which map to a specific neural pathway. A high-risk paradigm would clarify the temporal relation of cognitive dysfunction to clinical course.

METHOD

We compared euthymic offspring (age range: 18-32 years) of lithium-responsive bipolar parents with and without a previous lifetime history of psychiatric illness to healthy comparison subjects with a negative family history, on a VBM task that requires target location.

RESULTS

High-risk offspring with no lifetime psychiatric history performed the VBM task at levels of healthy controls. High-risk offspring with a previous history of a mood disorder, in complete remission, made significantly more errors at short target-mask intervals than control or never ill offspring. These higher error rates were not a consequence of faster response times.

CONCLUSIONS

There is preliminary evidence of specific cognitive dysfunction early in the course of illness in affected offspring of parents with lithium responsive BD. VBM is ideal for future longitudinal studies addressing whether cognitive dysfunction in BD is a trait marker or a consequence of illness manifestation.

MMPI as a measure of subthreshold and residual psychopathology among the offspring of lithium responsive and non-responsive bipolar parents

OBJECTIVES

In bipolar adults, the Minnesota Multiphasic Personality Inventory (MMPI) can detect residual symptoms and confirm completeness of remission, thus helping to predict response to lithium prophylaxis. In the high-risk and early onset bipolar populations, the association of the MMPI with clinical course and treatment response has not yet been studied. The present study compares MMPI profiles completed by the well or remitted offspring of two groups of bipolar parents divided on the basis of parental response to long-term lithium.

METHODS

As part of an ongoing prospective longitudinal high-risk study, offspring of bipolar parents determined to either respond or not respond to long-term lithium monotherapy completed the MMPI. At the time of MMPI completion, offspring were determined to be either well (unaffected) or clinically remitted (affected but euthymic) based on repeated prospective KSADS-PL format interviews conducted by a research psychiatrist and reviewed on a blind consensus basis.

RESULTS

While there was no difference in the MMPI scores between subgroups of unaffected offspring, there was a significant difference in profiles between remitted offspring. Specifically, affected offspring of lithium non-responders showed significantly higher average scores on scales 6, 8 and 0 compared with affected offspring of lithium responders. These findings are consistent with the differences in MMPI profiles taken at optimum between the respective parent subgroups.

CONCLUSIONS

The findings confirm the clinical observation that the affected offspring of lithium responders suffer from episodic fully remitting mood disorders, while the affected offspring of lithium non-responders suffer from mood disorders with incomplete remission. Further, the nature of the residual symptoms as indicated by the abnormal MMPIs support the view of heterogeneity of the bipolar diagnosis. The relevance to treatment response is discussed.

Identification of lithium-regulated genes in cultured lymphoblasts of lithium responsive subjects with bipolar disorder

Lithium, a common drug for the treatment of bipolar disorder (BD), requires chronic administration to prevent recurrences of the illness. The necessity for long-term treatment suggests that changes in genes expression are involved in the mechanism of its action. We studied effects of lithium on gene expression in lymphoblasts from BD patients, all excellent responders to lithium prophylaxis. Gene expression was analyzed using cDNA arrays that included a total of 2400 cDNAs. We found that chronic lithium treatment at a therapeutically relevant concentration decreased the expression of seven genes in lymphoblasts from lithium responders. Five of these candidate lithium-regulated genes, including alpha1B-adrenoceptor (alpha1B-AR), acetylcholine receptor protein alpha chain precursor (ACHR), cAMP-dependent 3',5'-cyclic phosphodiesterase 4D (PDE4D), substance-P receptor (SPR), and ras-related protein RAB7, were verified by Northern blotting analysis in lithium responders. None of these genes were regulated by lithium in healthy control subjects. When we compared the expression of these five genes between bipolar subjects and healthy control subjects at baseline, prior to lithium administration, we found that alpha1B-AR gene expression was higher in bipolar subjects than in healthy control subjects. Our findings indicate that alpha1B-AR may play an important role in the mechanism of action of lithium treatment.

Using technology to improve longitudinal studies: self-reporting with ChronoRecord in bipolar disorder

OBJECTIVES

Longitudinal studies are an optimal approach to investigating the highly variable course and outcome associated with bipolar disorder, but are expensive and often have missing data. This study validates patient self-reported mood ratings using a home computer-based system (ChronoRecord) with clinician mood ratings on the Hamilton Depression Rating scale (HAMD) and Young Mania Rating scale (YMRS), and investigates the patient acceptance of the technology.

METHODS

After brief training, outpatients with bipolar disorder were given the software version of an established paper based self-reporting form (ChronoSheet) to install on a home computer. Every day for 3 months, patients entered mood, medications, sleep, life events, and menstrual data. Weight was entered weekly.

RESULTS

Eighty of 96 (83%) patients returned 8662 days of data. The mean days of data returned was 114.7 +/- 32.3 SD The mean percentage of days missing for mood data was 6.1% +/- 9.3 SD, equivalent to missing 7.3 day of the 114.7 days. Self-reported ratings were strongly correlated with clinician HAMD ratings (-0.683, p < 0.001).

CONCLUSIONS

This study demonstrates concurrent validity between ChronoRecord and HAMD. Patients with bipolar disorder showed high acceptance of a computer-based system for self-reporting of daily data. Automation of data collection can reduce missing data and eliminate errors associated with data entry. This technology also enables on-going feedback for both patient and researcher during a long-term study.

The Electronic Assessment of the Longitudinal Course of Bipolar Disorder: The ChronoRecord Software

Longitudinal studies are the optimal approach when investigating the highly variable course of bipolar disorder, but such studies are expensive, prone to reporting errors and to missing data. Automation of data collection may reduce such errors and improve data quality. The ChronoRecord, validated software that patients can install on a home computer to report mood, medications, sleep, life events, weight and menstrual data, has been designed to achieve such automation. In the trial of the ChronoRecord reported here, 80 of 96 (83 %) patients with bipolar disorder showed high acceptance of this computer-based system for self-report, entering daily recordings for a period of 3-months. This new technology, in addition to providing an accurate longitudinal record for research purposes, also facilitates on-going patient feedback and accurate study monitoring.

Descartes' Passions of the soul--seeds of psychiatry?

Rene Descartes (1596-1650), often called the 'father of modern philosophy', aimed at rooting all knowledge in certainty so that our understanding of the world could progress without error. To achieve this, he needed at least one sure thing on which to build. Starting with the most basic knowledge, the fact of his own existence--cogito ergo sum (I think therefore I am), he systematically proceeded to explain the world. Such systematic understanding would be accessible to anyone who applied the Cartesian method, and in turn would lead to a good life. Descartes' Passions of the Soul was written according to his method of certainty and fits in with a meticulously refined worldview. It is one of the first systematic treatises to explain a wide array of emotions, both normal and abnormal. Based on the Cartesian dualistic model of mind and body, the work helps ground a long medical tradition of separating 'rational' consciousness from emotions. For Descartes, emotions arose from two sources, the intellect and the body (Passions of the Soul and Passions of the Body). The more subtle 'Passions of the Soul' were viewed as superior to coarser and often-troublesome emotions taking root in the body. It is interesting to note the absence of clarity, however, in Descartes' division of intellectual emotions from bodily emotions, perhaps revealing an enduring weakness in the dualistic model itself. The work grapples with the multi-causal nature of psychopathology and brings out complex interactions between temperament and life experience. While modern neuroscience makes ever-tighter associations between physiology and experience, many of the basic scientific challenges we face today are outlined in this 350-year-old book.

The cortisol awakening response in bipolar illness: a pilot study

OBJECTIVE

A growing body of data suggests that a significantly enhanced salivary cortisol response to waking may indicate an enduring tendency to abnormal cortisol regulation. Our objective was to apply the response test to a population already known to have long-term hypothalamo-pituitary-adrenocortical (HPA) axis dysregulation. We hypothesized that the free cortisol response to waking, believed to be genetically influenced, would be elevated in a significant percentage of cases, regardless of the afternoon Dexamethasone Suppression Test (DST) value.

METHOD

Using the free cortisol response to waking and the short daytime profile, we tested 18 clinically stable, lithium-responsive subjects from our long-term naturalistic follow-up of monthly DSTs. These tests include salivary testing every 15 minutes during the first hour of waking, followed by samples taken at 3:00 PM and 8:00 PM.

RESULTS

While clinically stable on lithium prophylaxis, patients with bipolar disorder (BD) showed a significantly enhanced salivary cortisol response to waking, compared with control subjects (P < 0.03). Cortisol levels 30 minutes after waking significantly exceeded those in the large normative data provided in the literature (P < 0.001).

CONCLUSIONS

Our observations support the hypothesis that the free cortisol response to waking can reflect relatively enduring HPA dysregulation, even when lithium-responsive BD patients are clinically well and their DSTs are normal. Because the test is easy to administer, the free cortisol response to waking may hold promise as a marker in studies of high-risk families predisposed to, or at risk for, mood disorders.

Selecting effective long-term treatment for bipolar patients: monotherapy and combinations

This article explores the roles of monotherapy and drug combinations in finding effective long-term treatment for individual patients with bipolar disorder. While current practice relies heavily on combinations, many bipolar patients can be successfully stabilized if the initial monotherapy is carefully selected according to the patient's clinical characteristics. The data show that (1) unequivocal responders to long-term monotherapies such as lithium, lamotrigine, or atypical neuroleptics each have a very different clinical profile, including clinical presentation and course, comorbidity, and, in particular, family history and (2) bipolar patients who respond very well to a long-term monotherapy have often completely failed on other monotherapies. Combinations appear indicated particularly in bipolar patients who are treatment-resistant to monotherapy, do not tolerate it well, or have not yet exhibited the clinical characteristics needed to choose an effective monotherapy.

JI, Craddock N, DePaulo JR, Baron M, Gershon ES, Ekholm J, Cichon S, Turecki G, Claes S, Kelsoe JR, Schofield PR, Badenhop RF, Morissette J, Coon H, Blackwood D, McInnes LA, Foroud T, Edenberg HJ, Reich T, Rice JP, Goate A, McInnis MG, McMahon FJ, Badner JA, Goldin LR, Bennett P, Willour VL, Zandi PP, Liu J, Gilliam C, Juo SH, Berrettini WH, Yoshikawa T, Peltonen L, Lönnqvist J, Nöthen MM, Schumacher J, Windemuth C, Rietschel M, Propping P, Maier W, Alda M, Grof P, Rouleau GA, Del-Favero J, Van Broeckhoven C, Mendlewicz J, Adolfsson R, Spence MA, Luebbert H, Adams LJ, Donald JA, Mitchell PB, Barden N, Shink E, Byerley W, Muir W, Visscher PM, Macgregor S, Gurling H, Kalsi G, McQuillin A, Escamilla MA, Reus VI, Leon P, Freimer NB, Ewald H, Kruse TA, Mors O, Radhakrishna U, Blouin JL, Antonarakis SE, Akarsu N. Genome scan meta-analysis of schizophrenia and bipolar disorder, part III: Bipolar disorder

Genome scans of bipolar disorder (BPD) have not produced consistent evidence for linkage. The rank-based genome scan meta-analysis (GSMA) method was applied to 18 BPD genome scan data sets in an effort to identify regions with significant support for linkage in the combined data. The two primary analyses considered available linkage data for "very narrow" (i.e., BP-I and schizoaffective disorder-BP) and "narrow" (i.e., adding BP-II disorder) disease models, with the ranks weighted for sample size. A "broad" model (i.e., adding recurrent major depression) and unweighted analyses were also performed. No region achieved genomewide statistical significance by several simulation-based criteria. The most significant P values (<.01) were observed on chromosomes 9p22.3-21.1 (very narrow), 10q11.21-22.1 (very narrow), and 14q24.1-32.12 (narrow). Nominally significant P values were observed in adjacent bins on chromosomes 9p and 18p-q, across all three disease models on chromosomes 14q and 18p-q, and across two models on chromosome 8q. Relatively few BPD pedigrees have been studied under narrow disease models relative to the schizophrenia GSMA data set, which produced more significant results. There was no overlap of the highest-ranked regions for the two disorders. The present results for the very narrow model are promising but suggest that more and larger data sets are needed. Alternatively, linkage might be detected in certain populations or subsets of pedigrees. The narrow and broad data sets had considerable power, according to simulation studies, but did not produce more highly significant evidence for linkage. We note that meta-analysis can sometimes provide support for linkage but cannot disprove linkage in any candidate region.

Does prophylaxis-delay in bipolar disorder influence outcome? Results from a long-term study of 147 patients

OBJECTIVE

This study investigated the impact of latency (the time between illness onset and initiation of prophylactic treatment) on the outcome of prophylaxis in bipolar disorders.

METHOD

The effect of prophylaxis delay (latency) on the course of illness was assessed in 147 patients. Dependent variables were: reduction of days spent in the hospital (prior to vs. during prophylaxis), time to first recurrence, and Morbidity-Index during prophylaxis (lithium or carbamazepine). Latency and other independent variables were tested using a multivariate approach.

RESULTS

Latency (9.3 years on average) had no significant effect on the subsequent response. Illness severity prior to prophylaxis, however, did predict the relative response. The course of illness during treatment could not be predicted by any one factor.

CONCLUSION

The delay in initiating prophylaxis appears to have no influence on prophylaxis outcome. Instead, those whose illness was more severe were treated earlier and these patients subsequently showed a relatively greater response. If severity is not controlled for as part of the analysis, latency may be mistaken as an important predictor for response.

A prospective study of the offspring of bipolar parents responsive and nonresponsive to lithium treatment

BACKGROUND

The descriptions of clinical course among bipolar youths vary significantly and differ markedly from the findings described in classical studies of bipolar adults. This difference may in part reflect genetic heterogeneity. Response to lithium monotherapy identifies a homogeneous subgroup of bipolar adults. The aim of this study was to prospectively characterize the clinical course, including antecedent and comorbid conditions, among the offspring of 2 groups of bipolar parents divided on the basis of response to lithium.

METHOD

Parents were identified from families participating in ongoing molecular genetic studies and selected from specialty affective disorder clinics. For each child, 1 parent met Research Diagnostic Criteria/DSM-IV criteria for bipolar I disorder and either response or nonresponse to lithium prophylaxis. The other parent had no lifetime history of a major psychiatric illness. Blind to family affiliation and lithium response, all eligible offspring aged 10 to 25 years were interviewed using the Schedule for Affective Disorders and Schizophrenia for School-Aged Children-Present and Lifetime Version (K-SADS-PL), and best-estimate diagnoses were made by a panel of experts. Offspring were then reassessed over a 5-year period.

RESULTS

Offspring of lithium responders (N = 34) had good premorbid functioning and manifested classical mood disorders with an episodic course. Comorbid conditions in this group remitted prior to the mood disorder. In contrast, offspring of lithium nonresponders (N = 21) had poorer premorbid functioning and manifested mood disorders with a chronic course. Comorbid conditions continued alongside the mood disorder. Clinical course among affected offspring was predicted by the disease course of the parent.

CONCLUSION

The pattern of clinical course, remitting or nonremitting, appears to be inherited. Among the offspring of lithium-responsive bipolar parents, an early-onset subgroup with a classical episodic clinical course can be identified.

Is response to prophylactic lithium a familial trait?

BACKGROUND

Selecting a drug according to the treatment response in a relative has been widely accepted advice in the management of mood disorders. However, this recommendation has not been adequately substantiated in the literature. We tested the hypothesis that response to long-term lithium treatment is a familial trait.

METHOD

We compared response to long-term lithium treatment in bipolar relatives of bipolar lithium responders and bipolar controls. Twenty-four relatives with bipolar disorder (as determined using the Schedule for Affective Disorders and Schizophrenia-Lifetime version [SADS-L] and Research Diagnostic Criteria [RDC]) were identified in families of 106 patients with lithium-responsive bipolar disorder. A consecutive series of 40 lithium-treated patients in a bipolar clinic (meeting RDC and DSM-IV criteria for bipolar disorder) served as a comparison group. Lithium response was evaluated on a rating scale reflecting the quality and quantity of available data.

RESULTS

The prevalence of unequivocal response among the relatives was 67%, as compared with the response rate of 35% in the comparison group (chi2 = 6.04, df = 1, p = .014).

CONCLUSION

This highly significant difference in response between relatives and the control group supports the view that the response to lithium prophylaxis clusters in families.

Stability of nucleic acid under the effect of UV radiation

Nucleic acids (combined with protein molecules) are essential constituents of the living systems playing an important role in the early evolution of life as well. A specific feature of these molecules has been found and directly confirmed recently: under the influence of short-wavelength UV radiation bipyrimidine photoproducts (cyclobutane dimers and 6-4 bipyrimidines) are induced and the reversion of them can be provoked by the same photons. However, reversion is preferred by the shorter wavelengths. With increasing ratio of the longer wavelength components of the radiation (using artificial UV sources and solar light on the Earth's surface) the impact of the reversible photoproducts in the harmful biological effect decreases and other photoproducts are dominant. Assuming the photoinduced reactions (dimerisation and reversion) are statistical events, during the irradiation the chance for a number of nucleoprotein molecules to survive the radiation damage can be reality. The theoretical and experimental basis of these assumptions will be discussed in the case of bacteriophage T7 nucleoprotein.

Psychiatric diagnoses in the context of genetic studies of bipolar disorder

Precise definition of the phenotype is an issue of critical importance for the future success of genetic studies of bipolar disorders. So far, an uncertain phenotypic spectrum and genetic heterogeneity are realities that have hampered progress in genetic studies. While recognition of a broader spectrum of related illnesses is important for some applications, for genetic studies a narrow spectrum of illness closely tied to the genotype is paramount. This paper highlights current dilemmas and trends associated with phenotype specification and traces historical approaches. Finally, we explore a number of strategic directions in the diagnostic approach to bipolar disorders that may better serve genetic studies.

Measures of attention and hyperactivity symptoms in a high-risk sample of children of bipolar parents

BACKGROUND

To determine whether significant symptoms of inattention were present among the offspring of well-characterized bipolar parents.

METHODS

We included 53 offspring of 30 parents meeting DSM-IV criteria for bipolar disorder diagnosed by consensus on the basis of a SADS-L interview and a wealth of longitudinal clinical data. The unaffected parent had no lifetime history of a major psychiatric illness. Offspring, prospectively followed for up to 5 years, completed psychometric measures of attention and mood when judged to be at a good level of functioning (well, remitted or treated).

RESULTS

Those offspring with any lifetime psychiatric diagnosis endorsed more subjective problems with attention. However, there was no measurable difference on tasks of sustained attention between those with and those without a lifetime psychiatric illness including affective disorder. There was a significant association between self-reported symptoms of depression and inattention, but no association between either self-report measure and an objective measure of sustained attention.

LIMITATIONS

This study was not intended to be a comprehensive neuropsychological investigation of at risk offspring.

CONCLUSIONS

In this high-risk population, subjective difficulty with attention appeared to be state-dependent, associated with the degree of subjective distress related to an underlying psychiatric illness.

Mapping susceptibility genes for bipolar disorder: a pharmacogenetic approach based on excellent response to lithium

Genetic mapping studies in bipolar disorder (BD) have been hampered by the unclear boundaries of the phenotypic spectrum, and possibly, by the complexity of the underlying genetic mechanisms, and heterogeneity. Among the suggested approaches to circumvent these problems, a pharmacogenetic strategy has been increasingly proposed. Several studies have indicated that patients with BD who respond well to lithium prophylaxis constitute a biologically distinct subgroup. In this study we have conducted a complete genome scan using 378 markers spaced at an average distance of 10 cM in 31 families ascertained through excellent lithium responders. Response to lithium was evaluated prospectively with an average follow-up of 12 years. Evidence for linkage was found with a locus on chromosome 15q14 (ACTC, lod score = 3.46, locus-specific P-value = 0.000014) and suggestive results were observed for another marker on chromosome 7q11.2 (D7S1816, lod score = 2.68, locus-specific P-value = 0.00011). Other interesting findings were obtained with markers on chromosomes 6 and 22, namely D6S1050 (lod score = 2.0, locus-specific P-value = 0.00004) and D22S420 (lod score = 1.91). Nonparametric linkage analysis provided additional support for the role of these loci. Further analyses of these results suggested that the locus on chromosome 15q14 may be implicated in the etiology of BD, whereas the 7q11.2 locus may be relevant for lithium response. In conclusion, our results provide original evidence suggesting that loci on 15q14 and 7q11.2 may be implicated in the pathogenesis of BD responsive to lithium.

Is lithium response related to G(s)alpha levels in transformed lymphoblasts from subjects with bipolar disorder?

BACKGROUND

A series of studies from independent laboratories have found increased levels of G(s)alpha in bipolar disorder in postmortem brain and peripheral blood cells. Long-term lithium administration blunts G-protein coupled cAMP signaling and may regulate G(s)alpha levels.

METHODS

We measured G(s)alpha in transformed lymphoblasts obtained from subjects with bipolar disorder and compared the findings with 23 age- and sex-matched controls. To reduce patient heterogeneity, we included only patients with an excellent response to lithium prophylaxis.

RESULTS

We found no differences in G(s)alpha protein levels measured with immunoblotting. G(s)alpha levels did not correlate with age, age of onset or duration of lithium therapy.

LIMITATIONS

This study made use of transformed lymphoblasts, which may not fully represent changes that occur in regionalized brain tissue. Furthermore, the transformed lymphoblasts used in this study were acquired from a select group of bipolar disorder subjects that responded to lithium treatment. Lastly, consideration has to be given to the small sample size of the study.

CONCLUSIONS

These results are consistent with recent observations suggesting that mood state and treatment effects may account at least in part for increased G(s)alpha levels in bipolar disorder.

CLINICAL RELEVANCE

This study suggests a need to further characterize biological phenotypes in subjects with mood disorders to enhance genetic studies.

Identification of three polymorphisms in the translated region of PLC-?1 and their investigation in lithium responsive bipolar disorder

Recently, we have found an association between bipolar disorder patients who are excellent responders to lithium prophylaxis and a polymorphic marker located in the first intron of the phospholipase C-gamma1 gene (PLC-gamma1) [Turecki et al., 1998: Mol Psychiatry 3:534-538]. As this variant is not known to be functional, we searched for other markers within the coding region, using single-strand conformational polymorphism (SSCP) analysis. We have identified three polymorphic sites localized in three different exons of the PLC-gamma1 gene (exons 9, 26, 31). Variation studies of these potentially functional sites in a group of 133 bipolar patients with an excellent response to lithium prophylaxis and a comparison group of 99 healthy controls showed no difference in genotype distributions for exon 9 (chi-square = 1.41, df = 2, P = 0.49), exon 26 (chi-square = 2.26, df = 2, P = 0.13), or exon 31 (chi-square = 1.41, df = 2, P = 0.49). Similar results were observed for allele distributions. These results suggest that our previous findings were not the result of linkage disequilibrium with these variants.

Anticipation in bipolar affective disorder: is age at onset a valid criterion?

Anticipation has been suggested among the genetic mechanisms of bipolar disorder (BD), prompting the search for unstable DNA sequences. Past studies of anticipation in BD have generally relied on observed shift in the age at onset between parental and offspring generations. Such a shift, however, may be caused by a number of other factors difficult to correct for. We investigated age at onset distributions in a sample of 161 related subjects and in a sample of "pseudofamilies" consisting of 320 unrelated subjects selected from a large epidemiological cohort using Monte-Carlo simulation to mimic the family sample. Comparison of age at onset distributions in both samples shows a difference between the generations, but of a similar magnitude in each sample. This suggests that age at onset alone may not be a sufficient criterion of anticipation. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:804-807, 2000.

Protective effect of pregnancy in women with lithium-responsive bipolar disorder

BACKGROUND

Recent psychiatric literature, while indicating a high incidence of postpartum depression, contains a few clinical reports which support our observations that women with episodic bipolar disorder often remain well without treatment during pregnancy. Our retrospective study statistically examines the clinical course of 28 women with RDC typical bipolar disorder, type I, who became pregnant prior to receiving successful lithium prophylaxis.

METHODS

We derived all data from the International Group for the Study of Lithium-treated Patients (IGSLI) database of excellent lithium responders. Data were compared both intraindividually, using data from three 9-month periods - immediately prior to pregnancy, pregnancy and postpartum - and interindividually, using never-pregnant women as controls.

RESULTS

Intraindividual data show that women with typical bipolar disorder, type I, experience significantly fewer and shorter recurrences during pregnancy than either before or after. Interindividual comparisons indicate that the recurrence risk during pregnancy is markedly lower than the clinical course would predict. Moreover, the few recurrences observed during pregnancy all took place in the last 5 weeks.

LIMITATIONS

Limiting cases to lithium responsive patients could have reduced heterogeneity and perhaps generalizability.

CONCLUSIONS

The findings, nonetheless, indicate a marked improvement of the clinical course of typical bipolar disorder, type I, lithium-responsive, during pregnancy. Exploring the underlying protective mechanisms may lead to new understanding of the pathophysiology of mood disorders and to new approaches to treatment and prevention.