C ONFLICTOS SOCIALES DESARROLLADOS EN MÁS DE UN DEPARTAMENTO

Depression is a common mental disorder affecting 121 million people worldwide [WHO, 2011]. In the US, about 1 in 10 individuals older than 12 are taking antidepressant drugs, according to a recent report from the US Centers for Disease Control and Preventions (CDC) National Center for Health Statistics [Kuehn, 2011]. Women appear more likely than men to develop depression: a gender imbalance in prevalence, incidence and morbid- ity risk develops in adolescence and persists throughout adult life [Piccinelli and Wilkin- son, 2000]. In the perinatal period, 10-15% of mothers are affected by depression [Cox et al., 1993, Dav´e et al., 2010, Kumar and Robson, 1984, O’Hara and Swain, 1996]. Although postnatal depression is generally thought of as a disorder affecting mothers, I will use the term ’postnatal’ as a specifier of time of onset (relating to the first year after childbirth) and as such use it for depression in both mothers and fathers.

1.3.1

Maternal early depression

There is long history of research into maternal mental illness around childbirth. For cen- turies, ’female hysteria’ was thought to be caused by disturbances of the uterus, such as during childbirth [King, 1993]. Louis Victor Marc´e was the first to write a book2 _en-

2_{Although Louis Victor Marc´e was the first to devote an either work to puerperal illness, there are}

earlier references. For instance, Gerard van Swieten, a Dutch physician, mentions puerperal sadness in his Commentaria in Hermanni Boerhaave aphorismos de cognoscendis et curandis morbis (page 601) from 1764. He writes that in the Dutch city of Haarlem, women were required by law to put a sign on their doors

tirely devoted to puerperal mental illness in 1858 [Marc, 1858]. In it, he attempted to estimate the number of women afflicted by ’puerperal madness’ (la folie puerprale) by counting women who had become ’mad’ after giving birth in hospital, and the number of women who had been admitted to asylums during pregnancy or shortly after childbirth. Although the numbers he found were very low (e.g. only 9 out of 3500 women in the General Lying-in Hospital in Westminster were identified as cases, while most other hos- pitals reported never having observed puerperal madness), Marc´e did stress the influence of maternal mental illness on the child.

A large meta-analysis of the rates of postpartum depression found an average rate of 12.8% (95%CI: 12.3-13.4%) [O’Hara and Swain, 1996]. This meta-analysis also found, by including data from 59 studies on a total of 12,810 women, that the prevalence of early maternal depression varied with the method of assessment. Studies in which women had been assessed for depression using a questionnaire reported higher prevalence rates than studies using interviews. Women who had been assessed with the EPDS had depression rates of 18.0% (95%CI: 16.1-19.9%) on average, compared to 7.2% (95%CI: 3.7-10.7%) for women assessed by an interview based on DSM-III.

Studies have found little evidence for a biological basis of maternal postnatal de- pression, and the main risk factors are the same as those for major depressive dis- orders [Cooper and Murray, 1998]. These risk factors include lower social class, negative life events, marital difficulties, lack of social support, and a history of depression (par- ticularly antenatal depression) [Cooper and Murray, 1998, Milgrom et al., 2008, O’Hara and Swain, 1996]. Some pregnancy-specific risk factors have also been identified, such as unplanned pregnancy, complications during pregnancy or childbirth, and not breast- feeding [Milgrom et al., 2008, Warner et al., 1996].

Rates of early depression for mothers are not necessarily higher than prevalence rates outside of the perinatal period [Cox et al., 1993]. However, the incidence of new

after they had given birth. This would prevent ’officers of justice’ from coming into their homes and giving them bad news (Haarlem was a city of sailors and merchants who travelled between Europe and Asia), which Van Swieten thought would lead to puerperal sadness. He recommended women to carefully avoid all emotions after childbirth.

depressive episodes might be higher in the first few weeks after delivery. Moreover, although the prevalence of depression is not increased, the effects of maternal depression on the child are thought be most potent during the first months postpartum (see section 1.4 on page 37 for more detail).

1.3.2

Fathers and early depression

Although most research on psychiatric morbidity during the perinatal period has fo- cussed on mothers, there are some studies that have included fathers as well. As early as 1931, Zilboorg described several case studies of ’depressive reactions related to parent- hood’ [Zilboorg, 1931]. The fathers described in his article experienced severe depressive reactions resulting in hospitalisations, and Zilboorg classified them as manic-depressives. In the Freudian spirit of the time, he attributed their psychopathology to suppressed inces- tuous thoughts about their mothers (and occasionally sisters), hatred or jealousy towards their fathers, and passive homosexuality.

In the following decades, case studies on mental illness in men around the perinatal period appeared sporadically in the scientific literature [Ballard and Davies, 1996]. From the 1980s onwards, small studies started to assess psychiatric morbidity in fathers. Most of these were biased in that they assessed partners of mothers with severe mental illness, or partners of mothers who were being treated in mother-baby units. As such, these studies often found high rates of paternal morbidity, ranging from 40% to 50% [Harvey and McGrath, 1988, Lovestone and Kumar, 1993].

Paternal early depression has received more attention in recent years. A large meta- analysis estimated that 10.4% (95%CI: 8.5-12.7%) of fathers experienced depression dur- ing their partners’ pregnancy or in the first year after childbirth [Paulson and Bazemore, 2010], which is slightly higher than the estimated 12-month prevalence of 5-7% for de- pression in men in general [Kessler RC, 2005, Kessler et al., 2003, 1993]. The study included information on 28,004 participants from 43 studies. The highest rate was ob- served in the 3- to 6-month postpartum period, with an estimated rate of 25.6% (95%CI: 17.3-36.1%) of fathers experiencing depression. However, there was a large amount of heterogeneity between studies, with estimates ranging from 0.7% [Thorpe et al., 1992] to 46.2% [Dudley et al., 2010], which is likely due to differences in study populations, types

of measurements (e.g. interview or questionnaire), and criteria used to define depression. Studies that have followed parents up longitudinally tend to find lower estimates of paternal postnatal depression compared to depression in mothers. For instance, a study in Spain that followed up 769 parents from pregnancy to 12 months postpartum found that 3.4% and 4.0% of fathers were depressed at 3 and 12 months postpartum [Escrib`a- Ag¨uir and Artazcoz, 2011]. A study using a UK primary care database (THIN) found a postnatal depression rate of 3.56 per 100 person-years for fathers [Dav´e et al., 2010]. These rates could be lower than the meta-analysis estimate due to fathers with depression being more likely to drop out of longitudinal studies, and because studies using diagnoses rather than questionnaires to define depression tend to find lower estimates.

The risk factors for early depression in fathers are similar to those for mothers: younger age, low income, low level of education, poor partner relationship quality, and worries about the economy and employment [Bergstrøm, 2013].