Abstract
Considering that treatment resistant depression (TRD) characterizes a large proportion of depressed patients in therapy, this important clinical problem has been surprisingly understudied. In this book, contributors, mostly from North America, have collectively attempted to present a critical evaluation of the various research and clinical aspects of TRD to meet this need, building on material presented at recent international conferences. The volume broadly consists of four sections, together with chapters addressing the economic impact of TRD and the ethical issues relevant to the treatment and research of patients with TRD.
The introduction highlights the methodological problems affecting defining and diagnosing TRD in clinical trials. Consensus on the operational criteria for TRD is still emerging due to unresolved issues on different elements of definition. The first section also contains a succinct overview of basic treatment approaches in TRD, namely matching treatment to depression subtypes, treatment optimization, switching antidepressants and combination strategies. In the second section, a good summary of the biological basis of TRD is provided. Hormonally based therapies are examined, looking at the role of thyroid, adrenocortical and oestrogen hormones in the neurobiology of mood disorders and antidepressant medications. Reviews of neuroimaging techniques in TRD, and their clinical and research utility are excellent. There are also interesting chapters on the psychoimmunologic factors and sleep abnormalities in TRD.
The third and fourth sections, which are the most clinically relevant, deal with the treatment approaches in the general and special patient population groups. The authors present a literature review of the use of SSRIs, SNRIs, and reversible and irreversible MAOIs in TRD in a systematic way. A discussion on the treatment considerations in managing non-responders to these medications is also provided although the role of tricyclic antidepressants was somewhat understressed. The chapter on electroconvulsive therapy (ECT) is well written and clinically useful but does not include recent data on the large multisite ECT study in the USA or other modalities of therapeutic brain stimulation (e.g. transcranial magnetic stimulation). Coverage on the review of thyroid augmentation is extensive but a little repetitive and also contradictory, reflecting the opinions of a number of leading researchers in the field. Some of the recommendations on drug combinations require more caution. Guidelines on combination and augmentation strategies based on clinical experience or anecdotal data are problematic due to the lack of systematic or controlled studies. Treatment combinations are generally not reported unless they were successful, hence resulting in biased reporting. Furthermore, the risk of drug interactions and toxicity should not be underestimated particularly in the practice of the inexperienced clinician.
To address the non-biological aspects of chronic mood disorders, the significant therapeutic role of cognitive therapy and psychosocial interventions are reviewed although data on supportive, interpersonal and psychodynamic therapies are scarce. There are excellent chapters on TRD in children and adolescents, the elderly, during pregnancy, bipolar disorders and comorbid psychiatric and medical disorders, with an emphasis on providing methodical practice guidelines and treatment algorithms. In considering the issue of suicide, the significant level of disability, social burden and human cost associated with TRD are brought to life with the description of typical clinical patterns found in patients with TRD.
Potentially this volume of work may serve the many clinicians and psychiatrists facing difficult treatment decisions in TRD, a field compounded by the dearth of systematic data. However, the availability of rigorously conducted randomized comparative studies of the numerous treatment options in TRD remains unlikely. The importance placed on treatment algorithms by the book can be somewhat futile and confusing given the lack of clear empirical data. As such, it is reassuring that several authors emphasize the need for individualized treatment as well as persistence in management for each patient with chronic mood disorder. Overall, the book provides up to date reviews and clinical approaches in TRD in a practical fashion.