False: The risk of major depression has been increasing in the Western world in recent decades. Moreover, there has been a shift forward in the age of onset and lifetime risk. This may be related to social changes including family relationships and the frequency of life events.

However, the observed increase may be due to artefacts of memory, higher subjective awareness, better definitions and better methods of identification (Johnstone et al 2004, p. 429; Sadock & Sadock 2005, p. 1581).

False: Mania is rare in older people. The community prevalence falls from 1.4% in younger adults to 0.1% in the over 65s. In the ECA study of 20 000 people, the 1-month prevalence of mania was 0.4–0.8% in 18–44-year-olds and 0.2% in 45–64-year-olds. No cases were identified in those aged above 64 years (Copeland et al 2002, p. 478; Gelder et al 2000, p. 1650).

True: Overall, depression is lower in the elderly. Females are at higher risk but the size of the gender difference is smaller in the elderly compared to the young (Gelder et al 2000, p. 1622).

True: The mean age of onset for BPAD is 17–21 years and for unipolar depression is 27 years (Gelder et al 2006, p. 230; Sadock & Sadock 2005, p. 1579).

True: Significant genetic correlations (from +0.4 to +0.6) between major depression and alcoholism in women have been demonstrated. The correlations are higher when using narrower criteria for alcoholism. The co-morbidity in women results from genetic factors that influence the risk of both disorders (Johnstone et al 2004, p. 431).

False: Following the positive findings of a relationship between obstetric complications and schizophrenia, a similar study investigated the relationship with affective psychoses, including mania, but found no association (Bain et al 2000).

True: Though not a strong association (Paykel 1992, p. 2003).

True: Murphy (1982) found that the rate of life events in the year preceding the onset of depression was similar for adults across the age range. However, the elderly tend to present with more medical problems. There was at least one severe life event in 48% of elderly people with depression compared to 23% of a control group. They included death of a loved one, life-threatening illness in someone close, major financial problems and enforced removal from one’s home (Butler & Pitt 1998, p. 112; Gelder et al 2000, p. 1622; Jacoby & Oppenheimer 2002, p. 644; Murphy 1982; Paykel 1992, p. 224).

False: Childhood sexual abuse doubles the risk of depression in females, but not in men (Spataro et al 2004).

False: Grief and depressive symptoms in women who terminate pregnancies for fetal anomalies and those who experience spontaneous perinatal loss are comparable (Zeanah et al 1993).

True: The concordance rate in twin genetic studies is the rate of concurrence of an index trait or disorder that occurs in one member also occurring in the co-twin. The concordance rate in BPAD is approximately 60% (range = 58–92%) in monozygotic and 20% (range 14–35%) in dizygotic twin pairs (Johnstone et al 2004, p. 430; Sadock & Sadock 2005, p. 1583).

False: There is substantial overlap between genetic loci identified for schizophrenia and bipolar disorders. Chromosome 13q has been of particular interest. Recent twin studies suggest that the chance of the monozygotic twin of a proband with bipolar disorder developing schizophrenia is 5–15% (Cardno et al 2002; Johnstone et al 2004, p. 162; Sadock & Sadock 2005, p. 1591).

False: Genetic factors have their greatest influence in younger ages. They are causally much less important in affective disorder starting in late life, while physical illness is significant in 60–75% of cases. The risk to first-degree relatives of probands with depressive disorder of late onset is ¹/₃ to ¹/₂ of those of early onset. However, up to a third of those with late-onset depression may have a family history of depression (Butler & Pitt 1998, p. 127; Gelder et al 2006, p. 512; Jacoby & Oppenheimer 2002, p. 637; Johnstone et al 2004, p. 646; Stein & Wilkinson 1998, p. 61).

False: In depression there is decreased REM-latency, i.e. the time from the onset of sleep to the onset of REM sleep is reduced. Moreover, there is increased REM density and increased total REM sleep (Sadock & Sadock 2005, p. 1601).

False: Delta waves occur in deep, non-REM sleep or slow wave sleep. The length of slow wave sleep is reduced in depression (Johnstone et al 2004, p. 437; Sadock & Sadock 2005, p. 1601).

False: The sensitivity of DST is approximately 60% and of TRH–TSH is approximately 25%. Neither test alone or in combination is of sufficient sensitivity or specificity to be of clinical use (Gelder et al 2000, p. 714; Johnstone et al 2004, p. 436; Puri & Hall 2004, p. 274).

False: Normal subjects have suppressed plasma cortisol levels throughout the following day after a dose of 1–2 mg of dexamethasone. A high proportion of severely depressed patients do not show this suppression effect and continue to produce normal/elevated levels of cortisol. However, the specificity and sensitivity are not sufficiently high to be used as a diagnostic test (Gelder et al 2000, p. 714; Murray et al 1997, p. 329).

True: Growth hormone is secreted from the anterior pituitary on stimulation by noradrenaline and dopamine. Growth hormone response to both the noradrenaline reuptake inhibitor desipramine and the noradrenaline α₂-adrenoceptor agonist clonidine is blunted in depression (Gelder et al 2006, p. 241; Sadock & Sadock 2005, p. 1600)

False: Blunted thyroid-stimulating hormone (TSH) response to thyrotropin-releasing hormone (TRH) occurs in 20–30% of patients with major depression. This does not normalize on remission of depression. They have an increased risk of relapse despite maintenance antidepressant therapy.

On the other hand, 5–10% of depressed patients have elevated basal TSH levels and an increased TSH response to TRH (Gelder et al 2006, p. 241; Sadock & Sadock 2005, p. 1600).

True: Melatonin secretion is inhibited by light. Melatonin secretion occurs particularly at night, with increased secretion hypothesized in the longer winter nights (Gelder et al 2000, p. 1352; Johnstone et al 2004, p. 428).

True: Platelet membranes contain secondary carrier systems for the uptake of 5-HT. It is generally agreed that 5-HT binding is reduced in depression compared to healthy controls (Paykel 1992, p. 224).

True: VMA is the major metabolite of adrenaline and noradrenaline (NE) in the periphery, while MHPG is the CNS metabolite. In depression, decreased central NE activity is evidenced by decreased urinary MHPG. However, a subgroup of depressed patients has elevated circulating levels of NE and its metabolites including VMA. This may suggest a dissociation of NE activity in the median forebrain bundle and the sympathomedullary systems (Anderson & Reid 2002, p. 19; Sadock & Sadock 2005, p. 1598).

False: In the 60s and 70s it was reported that the elderly manic patients had more depressive features, mood incongruent persecutory delusions, hostility and resentment, but less flight of ideas and infectious euphoria. Recent prospective studies have found no such differences except for more severe illness in the young (Copeland et al 2002, p. 479; Gelder et al 2000, p. 1650).

True: Pharmacogenetics is the study of genetic variations in pharmacodynamic and pharmacokinetic factors. Serotonin transporter variants have been associated with the likelihood of antidepressant response to SSRIs and also with the susceptibility to develop antidepressant-induced mania in bipolar disorder (King 2004, p. 51).

True: 90% of patients with mania experience a further episode of mood disturbance (Gelder et al 2006, p. 245).