A heterogeneous process, with a variable course, inconsistent response to treatment and of unknown cause (Belmaker RH).
Ranks first among psychiatric disorders that dominate the global burden of disease.
Associated with somatic, behavioral and emotional symptoms.
Depressed patients typically report physical rather than emotional symptoms.
Few illnesses interfere with the pursuit of happiness more than depression.
It can become self perpetuating as occupational, relationship and social losses accrue.
Approximately 6% of the worlds population is depressed at any given time.
A mood disorder.
Among the top 3 leading causes of years lived with disability and affects approximately 350 million people worldwide, with an increasing prevalence with increasing age.
Depression is the largest contributor to total years lived with disability in the Americas.
In the Diagnosis and Statistical Manual of Mental Disorders, Fifth edition: major depressive disorder, disruptive mood disorder, persistent depressive disorder, and premenstrual dysphoric disorder are included.
Associated with impaired energy, sleep, concentration and dysregulation of appetite (Gelenber AJ).
Nearly 90% of people with major depressive disorder report disturbed sleep.
Physical inactivity and comorbid depressive disorders occur commonly in the chronically ill.
5-12% of men and 10-25% of women have major depressive episodes during their lifetime.
Low levels of vitamin B12 and folic acid may contribute to depression.
Approximately half of the adults with a lifetime medical history of a major depressive disorder have never received treatment.
Depression is often associated with unemployment and poverty.
An estimated 28%+ of adults with depressive symptoms were undiagnosed or untreated.
Prevalence of diagnosed depression in adults 65 years or older doubled from 3% to 6% between 1992 and 2005.
Lifetime risk of developing major depressive disorder in the US is 16.2% (Kessler RC).
Lifetime incidence of depression is more than 20% in women and 12% in men.
Major depressive disorders affects approximately 14.8 million adults, and about 6.7% of the US population aged 18 years and older in a given year(Kessler RC et al).
2-5% of community dwelling adults age 65 years and older have criteria for the diagnosis of major depression.
Depression is especially common among those over 65 years of age and increases in frequency with age beyond this age.
In addition the risk of depression increases in relation to the age and frailty of the individual.
Late life depression refers to the occurrence of major depressive disorders in adults 60 years of age or older.
Major depressive disorders occur in up to 5% of community dwelling older adults and 8-16% of older adults have clinically significant depressive symptoms.
Major depressive disorders increase with medical morbidity and rates of 5-10% are reported in primary care, and as many as 37% experience such depression after critical care hospitalizations.
Genes help determine the likelihood of depression.
The origins of depression could be caused by a mixture of genetic and other factors.
Women are about 75% more likely than men to have experienced depression, and about 60% more likely to have experienced an anxiety disorder, suggesting the influence of gender.
Women tend to view themselves in a more negative way than men do, and that’s a factor for risk of depression.
The level of serotonin in the brain has a major affect on our emotions, thinking and behavior.
Anti depressants modify the amount of serotonin within the brain.
Serotonin plays a part in the forming of mental illness.
The TPH2 gene is a key part in controlling serotonin levels, and plays a part in the development of psychiatric disorders.
People who had a less functional short allele on a certain area of the serotonin gene have a more difficult time recovering from trauma compared to those with long alleles.
TPH2 is involved in the development of manic depression and depression.
Bad weather is not as common a depression factor as is generally believed.
Depressed individuals have a shorter life expectancy because depressed patients risk of dying by suicide, a higher rate of dying from other causes, and being more susceptible to medical conditions such as heart disease.
Up to 60% of people who die by suicide have a mood disorder such as major depression, and the risk is especially high if a person has a marked sense of hopelessness or has both depression and borderline personality disorder.
More than 50% of patients with depression report clinically significant anxiety and have greater refractoriness to standard treatments than patients who have depression without anxiety.
Reduced levels of allopregnanolone in the CSF normalizes after successful treatment of depression with antidepressants.
The lifetime risk of suicide associated with a diagnosis of major depression in the US is estimated at 3.4%, which averages two highly disparate figures of almost 7% for men and 1% for women.
As many as 10% of older adults in primary care and 30 to 50% in institutional and long-term care facilities are clinically depressed.
There is no evidence that the use of vitamin D3 in adults prevents depression.
Reduced levels of GABA are observed in the plasma, CSF, and cortical brain tissues of patients with depression.
Late life depression patients have a higher rates of coexisting conditions and concomitant use of medications than nondepressed counterparts.
More than 200 medications have been associated with depression or suicidal symptoms.
A major risk factor for sexual dysfunction.
Meta-analysis of patients with depression, 50-70% have risk for development of sexual dysfunction.
Medical problems such as chronic pain increase risk for depression.
Depression is associated with a worse outcomes for conditions such as cardiac disease.
When not successfully treated may become a persistent problem in as many as 40% of older adults.
Elderly patients with major depression are at high risk for recurrence disability and death.
17-37% of older patients have mild depressive symptomatology.
Depression in elderly is associated with lowered mood but is less common in older patients than in younger patients.
Depression in elderly is associated with irritability, anxiety and somatic symptoms more than in younger patients with depression.
Associated with all-cause mortality.
Late life depression associated with multiple cognitive impairments: including executive function impairment, attention and memory deficits.
Depression associated with an increased long-term risk of dementia.
Risk of depression 2 to 3 times higher among women compared to men.
Common in patients with chronic medical illness, persistent insomnia, functional decline associated with aging, in individuals who have experienced stressful life events and social decline.
Associated with increased risk of chronic illnesses and mortality and conversely chronic illnesses increased the risk of depression.
Depressive symptoms associated with impaired adherence to prescribed treatments, impaired quality of life, increased symptom burden, disability and functional and roll impairment and increased use of healthcare services.
Prevalence of depression is greatest in women during childbearing age.
2 to 3 times higher in first-degree relatives of depressed persons.
In a given year about 10% of the U.S. population older than 18 years have a depressive disorder.
6-9% of older patients have a major depressive disorder.
Seizures are common in depressed individuals and patients with seizures are more likely to be depressed.
As many as 10% of patients over the age of 65 years in primary care practices have significant depression.
Patients with depression have increases in inflammatory cytokines in the blood and cerebral spinal fluid.
Patients who have treatment resistant depression tend to have an increase in inflammatory markers.
Incidences of remission become progressively lower from the first course of antidepressant treatment at about 36.8% to the second course at about 30.6%, third course 13.7%, and fourth course 13%.
Failure of two courses of treatment is generally considered to define a group of patients who have treatment resistant depression.
With the treatment resistant depression there is greater severity and duration of illness, disability, physical illness, hospitalizations, risk of suicide, and economic costs compared with treatment to responsive depression.
35-70% of primary care patients with depression do not receive a diagnosis or receive inadequate treatment.
When patients present with somatic complaints primarily, as do two-thirds of those presenting to a primary physician, the diagnosis is frequently missed (Timonen M).
More than 80% of patients with depression improve when they receive appropriate treatment with medication, psychotherapy, or the combination.
About 70% of depressed patients do not receive treatment.
When elderly cease driving they increase symptoms of depression for a period of up to 6 years.
Diagnostic criteria for major depression-Diagnostic and Statistical Manual of Mental Disorders: five or more of the following:
depressed mood most of the day nearly every day
markedly diminished interest or pleasure in all or almost all activities
clinically significant weight loss in the absence of dieting or weight gain of more than 5% in body weight in a month or a decrease in appetite
insomnia or hypersomnia
observable psychomotor agitation or retardation
fatigue or loss of energy
feelings of worthlessness or excessive or inappropriate guilt
diminished ability to think or concentrate, or indecisiveness
recurrent thoughts of death, recurrent suicidal ideation without a specific
plan, a specific plan for committing suicide, or a suicide attempt
Diagnosis is a clinical one.
Initial screening for depression: Patient Health Questionnaire 2-during the last month, have you often been bothered by feeling down, depressed, or feeling hopeless? and During the past month, have you often been bothered by little interest or pleasure in doing things?
Positive answers to both of the Patient Health Questionnaire 2 is associated with a diagnostic sensitivity for depression of 96% and a specificity of 57% (Whooley MA, Arroll B).
Negative Patient Health Questionnaire responses make the diagnosis of depression unlikely (Williams JW Jr.).
Patient Health Questionnaire response positive to one question should prompt additional questions to establish the presence of major depression and the presence of at least 4 more symptoms for at least 2 weeks along with social and occupational impairment is required to make the diagnosis.
About 15% of depressed patients are refractory to all known types of therapy.
In the presence of medical problems is associated with higher morbidity and mortality rates compared with nondepressed patients with medical problems.
Associated with increased risk for the development of cardiovascular events in healthy patients, and for recurrent problems in patients with established coronary disease and for adverse outcomes after coronary artery bypass surgery.
Associated with increased rate of coronary heart disease and myocardial infarction.
Three times more common after myocardial than in the general community, and its presence increases the risk of CV events and mortality.
Among patients with cardiovascular disease preexisting depression and anxiety occurs on average 17 years before the cardiovascular event, and independently predicts hospitalizations (Chamberlain AM et al).
In a pooled analysis of 563,255 participants in 22 prospective studies baseline depressive symptoms were associated with cardiovascular disease incidence, but the magnitude of the association was modest.
Late-life depression occurring in persons 60 years of age or older.
Late life depression Is common and often associated with coexisting illnesses and cognitive dysfunction, or both.
Late life depression compared with older adults who have had initial depressive episodes earlier in life, are more likely to have neurologic abnormalities, including deficits on neuropsychological tests and age-related changes on neuroimaging.
Late life depression onset is more commonly associated with dementia than depression with earlier onset.
Depressed older adults are at increased risk for suicide.
Associated with significant increased risk of stroke morbidity and mortality.
Depression may contribute to stroke through neuroendocrine, and immunological, and inflammatory effects.
Depression is associated with C-reactive protein, IL-1, and Il-6, and these inflammatory factors have been associated with increased risk of stroke.
Depression is associated with poor health behaviors such as smoking, physical inactivity, poor diet, poor medication compliance, and obesity, which may increase the risk of stroke.
Independently associated a increase in risk of congestive heart failure among older patients with isolated hypertension.
Common comorbidity in patients with chronic heart failure, with a reported incidence of approximately 48% in this population.
Depression in patients with heart failure associated with increased mortality and hospitalization.
A negative prognostic factor for patients with coronary artery disease.
Prevalence in people diagnosed with cancer ranges between 22-29%.
As many as 70% of patients with depression have a MTHFR polymorphism and require additional CNS L-methylfolate.
Patients with MTHFR polymorphism have reduced CNS L-methylfolate and are 4 times more likely to develop depression.
Depressed individuals with low CNS L-methylfolate are 6 fold less likely to respond to antidepressant agents and 13 times more likely to relapse.
High risk of relapse after discontinuation of antidepressant therapy.
Women’s Health Initiative (WHI) study indicated that antidepressant therapy maybe detrimental with respect to stroke and total mortality in a large cohort of postmenopausal women.
Associated with an increased risk of type 2 diabetes.
Depression associated with a 60% increase in risk of type II diabetes (Mezuk B et al).
Diabetes increases the risk of depression.
Depression in diabetics associated with increased risk of dementia.
Depression twice as common in diabetics than in comparison and nondiabetic groups.
Higher consumption of chocolate associated with depression.
Associated with alterations in hypothalamus pituitary adrenal axis function with increased secretion and flattened circadian rhythm of cortisol.
Folate deficiency has been associated with depression and may impair the response to antidepressants and may contribute to relapse of depression.
Folate supplementation may improve depression.
It is suggested that an impaired corticosteroid receptor function is responsible for hyperactivation of the hypothalamic pituitary adrenal axis.
In women of childbearing age most commonly treated with selective serotonin reuptake inhibitors which have not been associated with increased risk of congenital malformations.
Minor depression refers to depressive symptoms that fail to rise to the standard of 4 or more symptoms beyond depressed mood and anhedonia.
Treatment options: watchful waiting, psychopharmacological treatment, and psychotherapy.
More than half of patients who receive antidepressants or psychotherapy respond to treatment.
The idyllic goal of treatment is remission rather than improvement, because maintaining remission for at least six months is associated with a reduced the chance of relapse.
Response rates are high even when patients receiving placebo or no treatment: in a metsanalysis of 44,240 patients from 177 studies 54% of patients responded to antidepressants and 38% responded to placebo.
Psychotherapy response rates are 54% compared to 41% with control patients.
Patients with depression who do not seek care of comparable response rates as those above. .
A substantial proportion of patients who improve with medication or psychotherapy would have recovered without treatment or with placebo.
Exercise reduces depressive symptoms among individuals with chronic illness.
Adolescents who stay physically active during their teens may lower the risk of depressive symptoms at age 18.
Meta-analyses show that moderate intensity exercise reduces depressive symptoms.
There is an inverse association between physical activity and depression symptoms.
Placebo controlled trials indicate that antidepressants and not more effective than placebo for mild depression, antidepressants are generally not recommended for patients with mild or less severe depression.
Stronger evidence exists for the benefit of antidepressants for patients with severe depression and a combination of psychotherapy and antidepressants is particularly effective for patients with persistent depression and more severe symptoms.
Selective serotonin-reuptake inhibitor is on the first line treatments for a late life depression.
Patients with mild to moderate depression and who undergo exercise training have the largest improvement in functional outcomes and achieve the largest antidepressant effects (Herring MP et al).
Relapse occurs in 56% of patients who discontinue treatment as compared with 39% of those who continue to receive anti-depressants.
Patients with three or more previous depressive episodes are more than twice as likely to have a relapse then those with fewer episodes.
Selective serotonin reuptake inhibitors are first-line pharmacotherapy for depression in the elderly.
Transcranial magnetic stimulation uses a focal electromagnetic field generated by a coil held over the scalp is positioned over the left prefrontal cortex is a newer treatment for depression.
The use of omega-3 fatty acids as supplements do not prevent depression.