Affective Disorders Flashcards
What are affective disorders?
Mental disorders characterized by dramatic changes or extremes of mood
What is affect in terms of affective disorders?
Mood
When do mood disorders typically arise and why?
- Many mood disorders emerge during adolescence when hormone concentrations change dramatically
- The interaction of these hormones with still-maturing brains can trigger dysregulated affective responses in susceptible individuals who have some combination of genetic and environmental factors
What are the symptoms of depression?
Major Depressive Disorder (MDD):
- reduced mood
- feelings of worthlessness
- general fatigue
- feelings of guilt, indecisiveness
- disruptions in sleep and food intake ->no directionality
- absence of pleasure
- suicidal thoughts/actions
- agitated motor symptoms
How do thyroid hormones influence MDD?
- Depressed people tend to have low thyroid function
- Recall that thyrotropin-releasing hormone (TRH) stimulates the release of thyroid-stimulating hormone (TSH)
- The release of TSH is blunted in patients with MDD compared to controls, even when given exogenous TRH
- TRH also stimulates prolactin release in non-depressed women, but not those with depression
- Elderly people also have reduced thyroid function and reduced mood
How does cortisol affect MDD?
- Patients with MDD have increased resistance to feedback actions of glucocorticoids
- changes in daily rhythm of cortisol secretion
- Increased baseline levels of cortisol due to overactive HPA (the negative feedback does not shut off the system)
How do estrogens affect MDD?
Deficits in E have been associated with depression
- in one double-blind study of 40 women who were hospitalized with depression, 90% of the women who were treated with E reported improved mood, and none of the placebo-treated women noted elevations
- Withdrawal from E after menopause increases reports of depression in women with a history of MDD
- E replacement after menopause increases mood
What is postpartum depression?
- All women experience similar endocrine changes during pregnancy and birth, but only some experience significant changes in mood
- many women experience mild postpartum depression called maternity blues or baby blues which lasts less than a week
- Mild to moderate PPD is experienced in about 15-20% of women, lasting 4-8 weeks
- in rare cases, women can display a temporary but severe form called postpartum depressive psychosis
What causes PPD?
- A combination of biological, social, and psychological factors are likely involved
- Specific hormone involvement: the opioid peptide beta-endorphin, CRH
- Social factors: lack of social support, pressures facing new parents
- New fathers also have reported feeling PPD
What is perimenstrual syndrome? (PMS)
- normal changes in steroid hormone concentration associated with the menstrual cycle are often associated with changes in behavior and feelings in women
- Some studies indicate that PMS symptoms are due to the hormonal changes themselves, whereas other suggest that the PMS results from physiological changes caused by the hormone changes
- The term ‘perimenstrual’ is used instead of ‘premenstrual’ because some of the effects remain elevated during menstruation
What is the social context of PMS?
- Much controversy surrounds PMS, from prevalence and defining of symptoms tto physical and psychological factors associated with it
- over the past 35 years it has gone from a relatively unknown medical condition to a well-known social phenomenon
- Both men and women use the term PMS to communicate a widely shared cultural understanding that women might become periodically aggressive, assertive, and cranky because of PMS
What is premenstrual dysphoric disorder (PMDD)?
At least 5 of the following symptoms are present for most of the time prior to and just after the onset of menstruation:
- Feeling suddenly sad, tearful, irritable or angry
- persistent and marked anger or irritability
- marked anxiety, tension
- markedly depressed mood, feelings of hopelessness, or self-deprecating thoughts
- Decreased interest in usual activities, work, friends, hobbies
- Easily fatigable or marked lack of energy.
- sense of difficulty concentrating
- marked change in appetite
- other physical symptoms like breast swelling or tenderness, headaches, joint or muscle pain, bloating, weight gain
How does progesterone impact PMS?
- most mood changes occur during the late luteal phase when P is high and E is starting to decrease
- but, no consistent differences in progesterone levels have been found in women who report PMS and those that do not
- Perhaps its not relative level or amount of P in the blood, but the drop in P that results in negative affect
- Progestins can affect GABA neurons by interacting with benzodiazepine receptors, essentially acting as an anti-anxiety drug
- The drop in P may have a withdrawal-type effect by. removing its action on GABAergic neurons
How do estrogens correlate to PMS?
- E could also be a factor, as estrogens affect fluid retention, hyperplasia of mammary tissue, and carbohydrate metabolism
- However, the date aren’t consistent in terms of levels of hormones and severity of symptoms
- it could be that target tissue sensitivity changes to a greater extent during the cycle in women who report PMS than those that don’t, or that these women are more responsive to circulating hormones in general
What is seasonal affective disorder? (SAD)
- SAD is characterized by depressed affect, lethargy, loss of libido, hypersomnia, excessive weight gain, carb cravings, anxiety, inability to focus attention in late autumn or winter
- symptoms usually begin between October and December and disappear with the onset of summer
- prevalence rates range from 1-10%, with higher numbers reported at higher latitudes
- standard treatment is with bright light therapy
