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Abstract

Depression is among the most prevalent and debilitating psychiatric disorders in the world. A striking feature of this disorder is that women are twice as likely to experience depression compared with men. Research indicates that genetic, biological and environmental factors contribute to the gender differences noted in depression. Women are more likely to suffer a greater number of and more severe stressful life events compared with men, although no gender difference has been found to explain the genetic vulnerability. As individuals with depression most frequently present to general practitioners, healthcare providers should consider screening for depression and using rigorous treatment strategies for depressed patients with comorbid medical illnesses.

Keywords

antidepressant pharmacotherapy cognitive–behavioral therapy depression gender hormones prevalence stressful events

As defined by the Diagnostic and Statistical Manual of Mental Disorders (4th Edition) (DSM-IV) [1], major depressive disorder is characterized by either the presence of depressed mood or diminished ability to experience pleasure (anhedonia) over a period of at least 2 weeks. In addition to one of these two primary symptoms, individuals must exhibit at least four additional symptoms, such as feelings of worthlessness or guilt, sleep disturbances, psychomotor agitation or retardation, and diminished ability to concentrate (Box 1).

Prevalence

Major depressive disorder, which will be subsequently referred to as depression, is one of the most frequently diagnosed psychiatric disorders, with current and lifetime prevalence rates reported to be 15 and 23%, respectively [2]. Indirect evidence suggests that the prevalence of depression has increased steadily during the mid-to-late 20th century, while at the same time the age of onset has decreased, with an average age of onset in the mid-twenties. The high prevalence rate of depression is even more concerning given the associated significant occupational and social impairment, and the high rate of associated comorbid medical and psychiatric illnesses [2 –4]. Given these data, it is not surprising that depression has been identified as one of the top five leading causes of disability and disease burden throughout the world [2 –4].

Perhaps the most striking feature of this debilitating disorder is that the prevalence estimate of depression is approximately twice as high for women than it is for men. Furthermore, this increased prevalence rate of depression is observed across different ethnic groups and countries [5 –8]. The lifetime prevalence rate of depression for women is approximately 21%, whereas it is approximately 12% for men [5 –8]. The rate of depression begins to increase for females around the age of 13 years and this higher prevalence rate for females continues throughout the lifespan [7 –10]. The purpose of this article is to review current knowledge of factors that contribute to the marked increase of depression among women and to describe gender differences in symptom presentation, course of illness and treatment outcome.

Factors that contribute to gender differences in depression

Reproductive factors

Reproductive factors such as menstrual cycle, pregnancy and menopause have been speculated to contribute to the high rate of depression among women, with some evidence that estrogen impacts the neurotransmitter system [8]. In fact, the WHO has identified peripartum and postpartum disorders as a significant global burden, which affects approximately 6% of the total world population [11]. Furthermore, researchers have confirmed that sex hormones affect the neurochemistry that influences emotions and mood states, although a specific biological mechanism explaining hormonal involvement has not been identified. Although sex hormone changes have been suggested to contribute to the increased rate of depression among women, there has been little research supporting this contention. Although some women do become depressed during periods of hormonal change (e.g., puberty, premenstrual period of menstrual cycle, menopause and postpartum period), it appears that these depressive episodes are not the result of the direct effects of hormonal changes on mood [8,12]. Moreover, depression during these periods of women's lives cannot account for the disparity of lifetime prevalence rates of depression among women [8,12].

Box 1.

Criteria for major depressive disorder according to the Diagnostic and Statistical Manual of Mental Disorders (4th Edition).

At least one of the following that significantly interferes with the person's life

Depressed mood most of the day, nearly every day, for at least 2 weeks

Loss of all interest and pleasure most of the day, nearly every day, for at least 2 weeks

At least four of the following additional symptoms have been present during the same 2-week period

Depressed mood (or irritable mood if a child or adolescent)

Loss of all interest and pleasure

Appetite or weight disturbance, either:

– Abnormal weight loss (when not dieting) or decrease in appetite

– Abnormal weight gain or increase in appetite

Sleep disturbance, either insomnia or hypersomnia

Psychomotor agitation or retardation

Fatigue or loss of energy nearly every day

Feelings of worthlessness or excessive or inappropriate guilt

Poor concentration or indecisiveness

Recurrent thoughts of death (not just fear of dying)

There has never been a manic episode, a mixed episode or a hypomanic episode

The symptoms cause clinically significant distress or impairment

The symptoms are not due to physical illness, alcohol, medication or street drugs

The symptoms are not due to normal bereavement

Stressful life events

A plethora of research in depression has consistently found that the rate of depression rises dramatically in adolescence and, starting early in adolescence (after the age of 13 years), more girls than boys become depressed [8,12]. Notably, the chronological age at which the rate of depression doubles for girls compared with boys also marks the time of puberty development. In fact, pubertal development predicts the emergence of the gender difference in depression better than age alone, and girls who pass through puberty early are at the greatest risk of developing depression [12].

What happens around puberty that may account for the general rise in depression in girls? Prior research has found differences in the kinds of stressful life events that typically occur in different age groups, and such stressful life events have been linked to the onset of depression. Specifically, preadolescents most frequently report family events, adolescents report interpersonal, peer-related events, and young adults report academic/achievement events [12,13]. Studies that have examined gender differences in stressful life events in adolescence have found that girls report more interpersonal (especially peer-related) stressors than boys, whereas boys report more negative academic and school-related events [12,13]. Other research has shown that early maturing girls choose more antisocial, deviant peers for friends compared with on-time or later-maturing girls, and associating with these more deviant peers may lead to the occurrence of a greater frequency of life stressors [12,13]. In addition, starting around the age of 8 years and persisting into young adulthood, Caucasian girls show less satisfaction with their physical appearance than do boys [12]. Moreover, adolescent girls express dissatisfaction with their body shape and weight even when they are within the normal weight range for their height [12]. Finally, early maturing girls are at higher risk for negative perceptions of their body image and weight compared with peers who mature on time [12,13].

Another stressful life event that has been directly implicated in the development of depression is childhood maltreatment and abuse [14]. Childhood trauma is particularly relevant as girls are substantially more likely to be exposed to childhood sexual abuse and assault than are boys [14].

Unfortunately, the increased rate of stressful life events for females continues into adulthood, with a number of specific stressful life events being noted to occur in greater frequency for adult women. For instance, women are substantially more likely to be victims of traumatic stress such as sexual abuse and assault than are men [15]. Although chronic stressors have received less empirical attention than acute stressors, women also appear to be more affected by chronic stress than men. These chronic stress conditions include single parenting, chronic health conditions, and caring for elderly and ill relatives [14]. Importantly, all of these chronic stressors have also been linked to depression [16]. Poverty is another significant chronic stressor experienced more frequently by women than men. Low socioeconomic status is also associated with a number of other related stressors such as poor access to healthcare, social isolation, poor nutrition and increased risk of victimization [15]. Not surprisingly, poverty has also been found to be predictive of depression.

Women's greater exposure to both acute and chronic stressful life experiences has biological consequences that further increase a woman's risk for depression. That is, research indicates that highly stressful conditions produce abnormalities in hypothalamatic–pituitary–adrenal (HPA) activity, such as changes in cortisol levels [17]. Moreover, chronic stress may result in a hypersecretion of cortisol, possibly leading to hippocampal atrophy due to neural death [18]. Abnormalities in HPA axis functioning have been speculated to play a critical role in the development of an initial depressive episode, as well as relapse of the disorder [19,20]. Thus, women's repeated exposure to stress throughout their lifespan may have direct biological consequences that contribute to the increased rate of depression among women.

Behavioral genetics

Although women experience stressful life events more frequently than men, it is unlikely that stressful life events alone lead to depression. In fact, a large number of people are resilient in the face of highly stressful life experiences [14]. Therefore, there must be other factors that are at least partially responsible for the increased risk of depression among women. Indeed, in recent years there has been emerging evidence that the development of depression is best accounted for by a transactional model of biological vulnerability and stressful life events [14,15,21]. That is, behavioral genetics research has documented that the risk of depression after a stressful life event is elevated among people who are at high genetic risk, whereas the risk is diminished among people who are at low genetic risk [22]. A recent prospective, longitudinal study by Caspi and colleagues examined whether specific genes exacerbate or buffer the effects of stressful life events on depression [21]. These investigators found that individuals with one or two copies of the short allele of the 5-hydroxytryptamine (5-HT) gene-linked polymorphic region (5-HTTLPR) were significantly more likely to exhibit clinical depression in relation to stressful life events compared with individuals homozygous for the long allele. In addition, Caspi and colleagues found that as the number of stressful life events increased (especially beyond four events), the risk for depression also increased, although this was only the case among those individuals with the short allele of the 5-HTTLPR. Importantly, these findings were subsequently replicated by Kendler and colleagues [23].

Taken together, these findings underscore the importance of considering both genetic and environmental factors when attempting to account for the development of depression. It is important to note that the study by Caspi and colleagues did not find any gender differences in genotype frequency, and this finding is consistent with other studies [14]. Unfortunately, Caspi and colleagues did not examine whether men and women differed in the frequency of stressful life events [21]. However, as noted previously, other studies have reported gender differences in frequency (and severity) of stressful life events, with women experiencing a significantly greater number and more severe stressful life events compared with men [14,15].

In summary, the development of depression appears to be best accounted for by a transactional model of a genetic vulnerability in combination with the occurrence of environmental factors, such as stressful life events. Environmental factors such as stressful life events may increase the occurrence of depression in women. Of course, there are many other possible environmental factors that probably contribute to the development and maintenance of depression in women that have not yet been identified.

Gender differences in the symptom presentation of depression

Women are more likely to report their depressive symptoms to others and to seek help from healthcare providers compared with men [7,24]. In contrast, men are more likely to cope with the symptoms of depression by engaging in alcohol and substance abuse [6,24,25]. However, epidemiological studies conducted with community samples indicate that women's greater frequency in reporting depression symptoms does not account for their increased prevalence rate of depression [7].

It is important to note that when both men and women do present for treatment of their depression, they most often present to medical healthcare providers rather than presenting to mental healthcare providers, and this is also the case for patients who present with depression without medical comorbidity [24,26,27]. As the prevalence rate for depression in medical patients is higher than the general population, and depression comorbidity is associated with increased mortality among the medically ill, it has been recommended that healthcare providers routinely screen for depression [28]. However, it should be noted that there is disagreement regarding whether practitioners should routinely screen for depression. Distinguishing the symptoms of depression from symptoms associated with a medical condition can often be a difficult task due to symptom overlap (e.g., sleep disturbances or weight loss/gain). However, depression is most readily detected in medically ill patients by the presence of cognitive symptoms (e.g., feelings of worthless, suicidal ideation, feelings of guilt and/or depressed mood) that cause the patient undue distress [28]. Although there has been a suggestion that patients should be routinely screened for depression in primary care, such screening only improves patient outcome when it is accompanied by notifying the patient of this screening and when the screening changes the provider's behavior (treatment approach) [28]. Moreover, there is some evidence that routine screening for depression is only cost effective for specific groups, such as older adults with diabetes [29].

Several studies have found that when men do present for help with depression, the depression is more likely to be missed by healthcare providers compared with when depressed women present for treatment [7,8]. There are several possible explanations for why depression is often not detected in men. One has to do with gender biases in diagnosis. That is, depression is viewed as a diagnosis associated with women [30]; thus, healthcare providers may not consider depression when assessing male patients. However, it is important to note that although men are less likely to suffer from depression than women, depression is still among the most prevalent psychiatric disorders in men, with a lifetime prvalence rate of approximately 12% [8].

The symptom presentation of depression is also different for men and women, and may further contribute to depression being missed more frequently in men. Men are more likely to manifest depression with symptoms of anger, whereas women are more likely to display prototypical symptoms, such as depressed mood, feelings of guilt or worthlessness, anxiety, psychomotor retardation, somatic concerns and increases in the frequency of crying [6,24,31]. In addition, women are more likely to report increases in appetite and weight, whereas men are more likely to report decreased appetite, weight loss and insomnia [6,7,24,31]. Women are also more likely to report a greater number of depression symptoms and greater distress compared with men, although depression severity level is comparable between men and women. Women are also more likely to attempt suicide, whereas the number of completed suicides is higher in men. This difference is, in part, due to gender differences in suicide methods. Men tend to choose more lethal methods such as the use of firearms and hanging, whereas women choose less lethal methods such as medication overdoses [6,7,24,31].

Gender differences in psychiatric and medical comorbidities have also been noted. Depressed women are more likely to have anxiety and eating disorder comorbidities, whereas depressed men are more likely to have alcohol and substance abuse disorders [4,6,24]. In terms of medical comorbidity, depressed women are more likely to present with thyroid disease, migraine headaches, chronic fatigue syndrome and fibromyal-gia relative to depressed men [4,6,7,31]. The presence of any of these comorbidities complicates the course of depression and affects treatment planning.

For both men and women, depression that is comorbid with medical illness has been identified as a notable problem due to the high prevalence rate of depression across medical conditions and the negative impact this comorbidity has on medical prognosis. For example, the prevalence rate of depression among patients with myocardial infarction is approximately 30% [32]; approximately 25% of poststroke patients meet diagnostic criteria for depression [33]; median point prevalence rates of depression among cancer patients are 22–29% [34,35]; and depression is three-times more prevalent among patients with diabetes compared with the general population [36]. A consistent finding across studies is that medical illness serves as a risk factor for depression [37,38]. Taken together, these findings suggest that healthcare providers may need to consider assessing for depression in both male and female patients with other conditions [28].

Course of depression

As noted previously, the average age of depression onset is in the mid-twenties. The average length of a depressive episode is 3–4 months. Unfortunately, once a person has had one episode of depression, he or she is very likely to experience at least one more episode during his/her lifetime [1,4,5,39]. Approximately 50% of patients will experience another episode of depression, with the average number of episodes throughout the lifetime being approximately four [1,39]. The majority of patients will suffer a recurrence within 5 years of the previous episode [1,39].

Several factors have been found to be predictive of recurrence, including history of multiple episodes, presence of dysthymia (chronic, mild depression), long duration of individual depression episodes, family history of affective disorders and poor symptom control during continuation therapy [39]. In approximately 12% of cases, depression becomes a chronic disorder with a duration of more than 2 years [1,39].

In addition to age of onset, there are several other gender differences in the course of depression that have been reported. There is some indication that women have slightly longer episodes of depression compared with men [5 –8,10], and women may be more likely than men to develop a chronic and recurrent course of illness [5 –8,10,25]. Among patients with a diagnosis of chronic depression, women may be more negatively affected than men, such that they have an earlier age of onset, greater severity of illness and greater functional impairment [25]. In addition, women are more likely to suffer an episode of depression related to seasonal changes (winter months), such that women are as much as four-times as likely as men to suffer from seasonal affective disorder [5 –8,10]. Last, some women experience the onset of depression in relation to hormonal changes such as during the postpartum period, with some evidence indicating that the occurrence of depression in relation to the postpartum period is substantially higher than has been previously documented [40].

As noted previously, both psychiatric (e.g., anxiety, personality and substance abuse disorders) and medical comorbidities negatively affect depression course, leading to poorer functioning and lower recovery rates, and this is the case for both men and women [37]. Comorbid medical illness (e.g., myocardial infarction, congestive heart failure, hypertension, diabetes and cancer) predisposes patients to a more chronic course of depression, including a greater risk of relapse and greater treatment resistance compared with depressed patients without medical comorbidity [37,39]. In addition, the presence of comorbid substance abuse leads to increased risk of suicide [39]. As already mentioned, women are more likely than men to have comorbid anxiety and eating disorders, whereas men are more likely to have comorbid alcohol and other substance abuse disorders [6 –8]. Medical comorbid illnesses are also more frequent in women compared with men, although the prevalence rate of comorbid depression and medical illness is high for both men and women [28,37].

Treatment

There are three primary forms of treatment for depression: psychotherapy, antidepressant psychopharmacology and electroconvulsive therapy (ECT).

Psychotherapy

Some research has found that cognitive–behavioral therapy (CBT) and interpersonal therapy (IPT) are equally efficacious in the treatment of mild-to-moderate depression, and these approaches appear superior to other psychotherapy approaches [41]. However, both CBT and IPT appear equally efficacious compared with psychopharmacology treatment using selective serotonin reuptake inhibitors (SSRIs). Although CBT and IPT are equally efficacious in treating depression, CBT appears to be superior to IPT in preventing depression relapses [41]. It has also been found that more severe depression requires a greater number of psychotherapy treatment sessions (more than 16 sessions) [41].

Although there have been a number of studies examining the efficacy of psychotherapy treatment approaches for depression, there has been relatively little investigation of gender differences in psychotherapy treatment response. What information does exist indicates that men and women respond comparably to CBT and IPT, with the exception of those affected by severe depression [42]. Women with mild-to-moderate depression respond less well to CBT, but not IPT, compared with severely and moderately depressed men and moderately depressed women [43]. As these findings are based on a limited number of studies, replication is necessary. Overall, the area of gender differences in response to psychotherapy treatment for depression is in need of greater attention.

Antidepressant pharmacotherapy

There are several classes of antidepressant medication; SSRIs, tricyclic antidepressants (TCAs), monoamine oxidase inhibitors (MAOIs) and serotonin–norepinephrine reuptake inhibitors (SNRIs). SSRIs are by far the most popular drugs used for antidepressant pharmacotherapy, as this class of medications is more convenient, relatively safe and has fewer side effects compared with TCAs and MAOIs. Overall, studies indicate that SSRIs and SNRIs are better tolerated than TCAs and MAOIs for depression, and there is some evidence that SSRIs are also more effective [42].

Overall, women are significantly more likely to be prescribed antidepressant medication than men [42]. Although there are limited data on gender differences in pharmacokinetics, there is some evidence of gender differences in drug absorption, bioavailability, drug distribution, metabolism and elimination [24,35,42]. These differences are mainly attributable to average gender differences in body weight and body fat, as well as hormone changes in women that slow gastric emptying and reduce gastric acid secretion [25,42,43]. The pharmacokinetic differences may result in higher plasma levels and longer half-lifes of antidepressants in women. However, there is no evidence that these differences are clinically relevant, with the possible exception of premenstrual breakthrough syndromes [25,42,43].

The topic of gender differences in response to antidepressant pharmacotherapy has only recently received empirical attention. The available data indicate several consistent findings. Women tolerate SSRIs, for example sertraline, less well than men, and this is especially the case for premenopausal women, who are three-times more likely than postmenopausal women to discontinue SSRI treatment [25,42,43]. Premenopausal women also appear to respond more favorably to SSRIs and MAOIs than TCAs [25,42 –45].

A meta-analysis of 35 studies examining response rates to the TCA imipramine found significant differences between men and women, with more men responding to imipramine than women [46]. Another study found women responded more slowly to treatment with imipramine compared with men [25]. A pooled analysis of eight studies comparing the efficacy of venlafaxine (immediate or extended release), SSRIs (fluoxetine, paroxetine or fluvoxamine) or placebo found that the response rate in women was significantly greater with venlafaxine than with SSRIs, whereas the response rate for SSRIs and venlafaxine was similar in men [47,48]. Remission rates for both men and women were significantly greater with venlafaxine than with SSRIs. However, this analysis was retrospective, which limits the clinical significance of the findings.

Another principal gender difference in antidepressant pharmacotherapy response is observed in younger women, particularly among those with reverse neurovegetative symptoms. For this group, the SSRIs have clearly become the treatment of choice and, when they are ineffective, MAOIs such as phenelzine have well-established value [31,45]. Men and postmenopausal women appear to be equally responsive to SSRIs, TCAs and MAOIs [31]. In addition, there is some evidence that, compared with men, women may respond more favorably to ECT [42].

As there is evidence that female sex hormones may affect antidepressant treatment response [25,44], some investigators have examined whether hormone replacement therapy (HRT) improves antidepressant response. The findings from these studies have been mixed. Two studies indicated that estrogen with SSRIs might be efficacious in the treatment of depression among perimenopausal women [48,49]. However, several increased health risks have been associated with HRT [50]. Observational studies have found that women currently receiving HRT have an increased risk for breast cancer compared with women not currently receiving HRT, and this risk increases for women receiving HRT for longer than 5 years [51]. However, the increased risk with HRT almost completely disappears once HRT is stopped [51]. Research has also demonstrated an increased risk of endometrial cancer with increased dosage and duration of HRT use [52]. Although there is some evidence that combining estrogen with SSRIs may be beneficial in treating depression among perimenopausal women, the addition of HRT to antidepressant medication for women who are unresponsive to antidepressant medication alone must be carefully considered given the increased health risks of HRT.

Treating depression in patients with comorbid medical illness

As noted previously, depression is highly prevalent in medically ill populations, and the presence of depression in this population is associated with increased morbidity and mortality [28,37,53]. Although antidepressant medications have been shown to be an effective treatment in this population [54 –57], research indicates that physicians prescribe antidepressants less frequently and in lower doses for medically ill patients compared with patients who have depression alone [37]. Given that depression relapse is higher in medically ill patients and these patients are more likely to be nonrespon-sive to antidepressant medication than patients with depression alone, physicians should be prepared to use treatment strategies that are recommended for treatment-resistant depression. These strategies include dose increases, augmentation or switching antidepressant medications [37,58,59]. In addition, antidepressant medication in combination with CBT has been demonstrated to be most efficacious for medically ill populations [37,60]. Consequently, the combination of antidepressant medication and CBT has been recommended for both depressed men and women who have comorbid medical ilnesses [28,37,60].

Executive summary

Definition

Depression is characterized by depressed mood, loss of interest in pleasurable activities, feelings of guilt and worthlessness, sleep disturbance, impaired concentration, suicidal thoughts and psychomotor disturbances.

Prevalence

Depression is one of the most prevalent psychiatric disorders, affecting approximately 15% of the population worldwide.

The rate of depression is twice as high for women as it is for men, with lifetime prevalence rates of 21 and 12%, respectively.

Etiology

Depression appears to be best accounted for by a transactional model of stressful life events in combination with genetic vulnerability.

Women are at a greater risk for experiencing a greater number and more severe stressful events than men, and this appears to at least partially account for the increased prevalence rate of depression in women.

Recent research has identified the 5-hydroxytryptamine (5-HT)TLPR gene as a specific biological vulnerability for depression following a stressful life event, although gender differences in this biological vulnerability have not been found.

Symptom presentation

Depressed women are more likely to report depressed mood, feelings of worthlessness, anxiety, psychomotor retardation, somatic concerns, and increases in appetite and weight gain.

Depressed men are more likely to report loss of appetite, weight loss, insomnia, anger, irritability, and are more likely to engage in alcohol and substance abuse than depressed women.

Due to the high rate of depression among the medically ill and the negative impact comorbid depression has on disease progression and overall mortality rate, physicians are encouraged to routinely assess for depression in both male and female patients with other disorders.

Course

The first episode of depression typically occurs around the mid-twenties.

The majority of depressed individuals will experience approximately four episodes of depression during their lifetimes, with the recurrence of depression usually occurring within 5 years of the previous episode.

Gender differences in the course of depression include a slightly younger age of onset, longer duration of depressive episodes and a more chronic course of depression in women compared with men.

Depression that is comorbid with psychiatric and medical illness is associated with a more chronic and severe course of depression than depression alone.

Treatment

Depressed women respond better to specific serotonin reuptake inhibitors than tricyclic antidepressants, and this is especially the case for younger women with reverse neurovegetative symptoms. However, women and men do not respond differently to new antidepressant medications such as buproprion, mirtazapine and serotonin-norepinephrine reuptake inhibitors.

Men appear to respond equally well to all forms of antidepressant medications.

Given the associated health risks, hormone replacement therapy is not recommended to treat depression, but should be carefully considered for women who have demonstrated treatment resistance to antidepressant medication.

For both men and women who have comorbid medical conditions, the recommended treatment strategy is a combination of antidepressant medication (higher dose than for the treatment of depression alone) and cognitive-behavioral psychotherapy.

Conclusion

Depression is one of the leading health concerns worldwide. Although depression is highly prevalent in both men and women, it affects twice as many women as men. This increased prevalence rate for women emerges around the age of 13 years and continues throughout the lifespan. Factors that contribute to the increased rate of depression in women include greater incidence of significant stressful life events, greater likelihood of reporting depression symptoms, greater likelihood of presenting for treatment and a gender diagnostic bias. Moreover, depressed women are more likely than depressed men to present with psychiatric (e.g., anxiety and eating disorders) and medical comorbidity, and such comorbidity negatively impacts the course of depression and treatment, although the negative impact appears comparable for both men and women. Research indicates that depression in patients with medical comorbidities should be treated with a combination of CBT and antidepressant medication. Moreover, the dose of antidepressant medication will need to be increased, and switching antidepressant medication will probably be necessary. Overall, women appear to respond to SSRIs better than TCAs, and this is especially the case for younger women with reverse neurovegetative symptoms. There are some findings that indicate that buproprion may be the best medication for the treatment of reverse neurovegetative symptoms [61]. In contrast, men appear to respond equally well to various forms of antidepressant pharmacotherapy. Although there is some evidence that HRT can increase the efficacy of treatment for women in the menopausal transition, the use of HRT is cautioned given the small but significant associated health risks.

Given the high prevalence of depression in both men and women and the increased mortality rates in depressed patients who have comorbid medical illness, primary care physicians should consider assessing for depression among both male and female patients. The assessment of the cognitive symptoms of depression can aid practitioners in distinguishing depression from medical conditions.

Future perspective

Understanding why some individuals develop depression following a stressful life event whereas others are resilient has been a challenge for the field. Recent research identifying a specific gene that interacts with stressful life events to predict the development of depression represents a major advance. Given the technological sophistication of the field, it is likely that investigators will continue to identify specific genes involved in the development and maintenance of depression. Such findings may also shed light on why women are more likely to develop depression and have a worse course of the illness than men.

Given the high prevalence rate of depression worldwide and its associated costs, routine screening for depression by healthcare providers will probably become commonplace. As routine screening for depression has been recommended, the field can also expect the development of efficient depression screening tools that will facilitate such screening.

With the increase of depression screening, we can expect to see advancement in treatments for depression. Although general treatment strategies have been recommended for patients with comorbid depression and medical illness, these strategies will need to be refined for specific medical populations. In addition, the area of gender differences in response to treatment for depression has received relatively little attention. However, this area has started to gain attention in recent years. Although the field has gained some insight into gender differences in response to antidepressant medications, a greater understanding of these differences will likely occur in coming years. This will also be the case for gender differences in psychotherapy for depression, which has been a neglected area of research.

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Gender Differences in Depression

Abstract

Keywords

Prevalence

Factors that contribute to gender differences in depression

Reproductive factors

Stressful life events

Behavioral genetics

Gender differences in the symptom presentation of depression

Course of depression

Treatment

Psychotherapy

Antidepressant pharmacotherapy

Treating depression in patients with comorbid medical illness

Conclusion

Future perspective

References