Discussion: The Impact of Ethnicity on Antidepressant Therapy
Psychopharmacologic Approaches to Treatment
Case 1: The Man Whose Anti-Depressants Stopped Working
In the above case, the client is a 63-year old who shows signs of depression and anxiety. In order to successfully diagnose the condition, a psychiatrist nurse would need to ask certain questions depending on the tool they will intend to adopt. In the present case, and given the history of the patient, one would ask the following questions:
- How can you describe your sleep pattern for the last two weeks?
- Have you entertained suicidal ideations of late?
- Have you lost interest in anything that was initially enjoyable to you?
Asking these questions is important because of several reasons. The first reason is that they help a nurse to determine whether the common symptoms of depression are present in a patient. Moreover, these questions, specifically the third one, would help the nurse determine the level of impact that the symptoms have on the patient’s capacity to function. Lastly, they help a psychiatric mental health nurse practitioner determine how the symptoms affect a patient’s ability to maintain relationships with other people.
Screening a patient for depression may also entail asking for opinions from third parties. Given that the patient is married, the very first person to ask about the presence of certain depressive symptoms will be his wife. Studies have suggested that the involvement of family members in the holistic management of depression has improved the process (Zhang & Wudong, 2013). Hence, the nurse will ask the wife to reveal the functioning of the family- Do you think that your family has been functioning normally in the last 3 months? Also, studies have produced considerable evidence in support of the notion that impaired family functioning may lead to depression. Thus, by asking this question, the nurse practitioner will look to establish whether family functioning could have contributed to the patient’s condition.
In addition to the wife, the nurse will also question the patient’s children. These children can play an integral role in diagnostic process. The reason for using their subjective assessment to determine the existence of depression is founded on the fact that they may have noticed changes in their father’s behavior. Thus, in order to discover the existence of these changes, the nurse practitioner needs to ask them, “Is your father able to concentrate when holding conversations?” Asking this question enables a nurse to gauge the concentration levels of the patient with a view of determining whether the patient has difficulties in sustaining thoughts during conversations with his children. Discussion: The Impact of Ethnicity on Antidepressant Therapy
Physical Exams and Diagnostic Tests
The diagnosis of depression takes many forms. The multidimensional approach to depression intends to eliminate another medical cause for the condition. Research works have indicated that physical examination plays a fundamental role in this diagnostic process (Ghaemi, 2013). For the present patient, and given his age, a nurse will order for physical examination on his neurological and endocrine systems. Specifically, the nurse will order for hypothyroidism and hyperthyroidism tests. Moreover, the patient will undergo central nervous system tumors tests and scans for head traumas.
In addition, further confirmatory tests may become necessary to differentially diagnose the condition. A diagnosis of depression may not be complete without a psychiatric evaluation of the patient. During this period, the patient will reveal their behavior patterns, feelings, thoughts, and symptoms. To successfully conduct the process, the mental health practitioner may ask the patient to fill in a questionnaire if they do not have the confidence to answer the questions in a face-to-face setting. Also, the mental health professional may enlist the services of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria (Ghaemi, 2013). The DMS-5 allows the practitioner to confirm if the patient meets the criteria for depression diagnosis. These physical examinations and diagnostic tests are important as they will help the nurse practitioner to rule out other causes of the condition. In addition, they will allow the nurse to eliminate or even determine the presence of co-morbidity with other mental health conditions.
Differential Diagnosis of the Patient
The differential diagnosis of the patient’s condition will entail a broad range of conditions given his symptoms. However, the following three conditions are more likely to present with the condition: anxiety disorder, obstructive sleep apnea, and adjustment disorder with depressive mood due to marital problems. Out of the above conditions, anxiety disorder has the highest probability of presenting. During the preceding depressive episodes, anxiety was a constant as a symptom.
Pharmacologic Agents for the Patient
The usage of certain pharmacological agents has proven essential in the management of major depressive disorders. In the present case, the psychopharmacological therapy that the nurse can formulate for the patient includes a selective serotonin reuptake inhibitor (sertraline) or a serotonin-norepinephrine reuptake inhibitor (venlafaxine). If the therapy consists of Sertraline, then the patient should be given an initial dose of 50 mg orally once per day (Stahl, 2014). This will be followed by a maintenance dose of between 50-200 mg depending on the maximum effective and safe dose for the patient. However, if the pharmacotherapy comprises venlafaxine, the patient will be started on Effexor XR at 75 mg once daily (Stahl, 2014). Upon monitoring, the dosage could be increased by 75 mg up to 225 mg maximum, contingent upon the patient’s reaction to the same. The mechanisms of action of the two and how they quickly achieve their peak plasma concentration levels make them prime candidates for the therapy.
However, whereas the patient responded well to Sertraline, the mechanism of actions of the two drugs above would make Effexor XR to be more effective. Whereas the two drugs target the inhibition of the re-absorption of serotonin, Effexor XR additionally targets the reabsorption of norepinephrine (Stahl, 2013). Both norepinephrine and serotonin play fundamental roles in the transmission of feel-good messages between cells in the brain. Thus, inhibiting the reuptake of norepinephrine and serotonin makes Effexor XR preferable based on mechanism of action alone.
Effect of Ethnicity on Effector XR
Studies have shown that the dosage of Effector XR may be manipulated according to the ethnicity of a patient. The enzyme CYP2D6 catalyzes the conversion of venlafaxine to its active metabolite O-desmethylvenlafaxine (ODV). The enzyme above has a functional variant known as CYP2D6*1 and nonfunctional variants called CYP2D6*4 and CYP2D6*4 that are prevalent in Caucasian ethnicities (Dean, 2015). Hence, given that the patient is of this ethnicity, he is a poor metabolizer of the drug. According to a study by the Pharmacogenetics Working Group of the Royal Dutch Association for the Advancement of Pharmacy (KNMP), the necessary data for the calculation of dose adjustment for poor metabolizers was insufficient. However, the FDA asserted that there are no varied dosing regimens for either poor or extensive metabolizers (Dean, 2015), which implies that the dosage for the present patient could be adjusted to 150% of the normal dose. Discussion: The Impact of Ethnicity on Antidepressant Therapy
The analysis of this case has revealed fundamental lessons to the nurse. The case has shown that major depressive disorders are recurrent in nature. Moreover, the periods between subsequent episodes shorten as the recurrences occur. Thus, one needs to be keen as they manage patients with the condition. Secondly, the case study has revealed that if the treatment regimen is not properly done, then a patient runs the risk of becoming resistant to anti-depressants. This implies that at a certain period, it will become impossible to treat such a patient. Therefore, the nurse will make sure that they prescribe maintenance doses for patients at the third recurrence even with remission. This will ensure that the probability of a relapse reduces significantly for the nurse’s patients.
References: Discussion: The Impact of Ethnicity on Antidepressant Therapy
Dean, L. (2015, July 27). Venlafaxine Therapy and CYP2D6 Genotype – Medical Genetics Summaries – NCBI Bookshelf. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK305561/
Ghaemi, S. N. (2013). On depression: Drugs, diagnosis, and despair in the modern world. Baltimore: Johns Hopkins University Press.
Stahl, S. M. (2013). Stahl’s essential psychopharmacology: Neuroscientific basis and practical applications (4th ed.). New York, NY: Cambridge University Press.
Stahl, S. M. (2014). The prescriber’s guide (5th ed.). New York, NY: Cambridge University Press.
Wang, J., & Xudong, Z. (2013). Perceived family functioning in depressed Chinese couples: A cross-sectional study. Nursing and Health Sciences, 15, 9-14.
The Sequenced Treatment Alternatives to Relieve Depression (STAR*D) Study revealed poorer antidepressant treatment response among black compared with white participants. This racial disparity persisted even after socioeconomic and baseline clinical factors were taken into account. Some studies have suggested genetic contributions to this disparity, but none have attempted to disentangle race and genetic ancestry. Here we used genome-wide single-nucleotide polymorphism (SNP) data to examine independent contributions of race and genetic ancestry to citalopram response. Secondary data analyses included 1877 STAR*D participants who completed an average of 10 weeks of citalopram treatment and provided DNA samples. Participants reported their race as White (n=1464), black (n=299) or other/mixed (n=114). Genetic ancestry was estimated by multidimensional scaling (MDS) analyses of about 500 000 SNPs. Ancestry proportions were estimated by STRUCTURE. Structural equation modeling was used to examine the direct and indirect effects of observed and latent predictors of response, defined as change in the Quick Inventory of Depressive Symptomatology (QIDS) score from baseline to exit. Socioeconomic and baseline clinical factors, race, and anxiety significantly predicted response, as previously reported. However, direct effects of race disappeared in all models that included genetic ancestry. Genetic African ancestry predicted lower treatment response in all models. Although socioeconomic and baseline clinical factors drive racial differences in antidepressant response, genetic ancestry, rather than self-reported race, explains a significant fraction of the residual differences. Larger samples would be needed to identify the specific genetic mechanisms that may be involved, but these findings underscore the importance of including more African-American patients in drug trials.