33 Affective disorders in women with intellectual disabilities

The issue of gender and depression within the general population has been given substantial research attention and an association between female gender and increased risk for depression is established. Adverse childhood experiences, sociocultural roles, and vulnerability to life events are thought to increase the prevalence, incidence, and morbidity risk of depressive disorders in females. Biological factors seem to play a less important role in the emergence of gender differences (Piccinelli et al. 2000).

Affective disorder, and in particular depression, is more common in people with intellectual disabilities (ID). Higher rates of physical illness including epilepsy, socioeconomic adversity, past experience of abuse, and reduced life supports are thought to be relevant risk factors (Richards et al. 2001; Lunsky 2003; De Collishaw and Maughan 2004). When people with ID become depressed, all psychological and somatic symptoms of depression can be observed, but changes are often subtle and develop over time. Depression in this population often remains undiagnosed, atypical symptoms are common, and self-injurious or aggressive behaviour may dominate the clinical picture of people with more severe ID (Gravestock et al. 2005).

In the Diagnostic Criteria for Psychiatric Disorders for use with Adults with Learning Disabilities/Mental Retardation (DC-LD) (Royal College of Psychiatrists 2001) the following disorders are classified under affective disorders:

In this chapter, we will discuss the presentation of two major disorders, depression and bipolar affective disorder in women with ID. We will highlight epidemiological studies that have taken gender issues into account and explore gender-related risk factors. The assessment of females with ID and affective disorder will be discussed, as well as diagnostic, treatment, and service delivery issues for this highly vulnerable group.

Few studies have presented results separately for men and women with ID and affective disorder. In contrast to the wealth of gender-related research in the general population, there is a continuing lack of evidence base and robust epidemiological data regarding this population. However, several studies documented that depressive disorders are more common in woman than in men with ID (Hastings et al. 2004; Lunsky and Palucka 2004; Lunsky and Canrinus 2005; Cooper et al. 2007).

Cooper et al. (2007), in a population-based study of 1023 adults with an ID, found a 3.8% point prevalence of affective disorder, which was higher than that of the general population. Comprehensive individual assessments with each person with ID were conducted and DC-LD diagnostic criteria were employed. A point prevalence of 0.6% was yielded for mania. Additionally, 1.0% of the sample had bipolar disorder currently in remission, and 0.1% had previous episode of mania currently in remission. There was no conclusion, however, regarding potential risk factors that could explain the gender differences. Indeed, whether higher rates of depression in females with ID are owing to biological or psychosocial influences remains relatively unexplored (Stavrakaki and Lunsky 2007).

A population-based study by Hastings et al. (2004) of over 1000 adults with ID demonstrated a significantly higher rate of affective symptoms in women than in men, as measured by the PAS-ADD Checklist (Moss et al. 1998). One recent study examined gender differences in people with ID admitted to inpatients units. In this study, Lunsky et al. (2009) compared 1971 men and women with and without ID, admitted to psychiatric units, in terms of diagnosis and clinical issues. Amongst inpatients with ID (126 females and 243 males), females were more likely to have a diagnosis of affective disorder and a past history of sexual abuse. Men were more likely to misuse substances, show aggressive behaviour and have forensic issues. Gender difference patterns found for persons with ID and affective disorder were similar to gender differences in inpatients without ID.

Women and men with ID seem to present equal rates of bipolar affective disorder, as in general population studies. However, a later onset of bipolar illness has been suggested for females with ID (Glue 1989; Vanstraelen and Tyrer 1999). Cain et al. (2003) reviewed four groups of people with ID and additional diagnoses of bipolar affective disorder, depression, psychotic depression, schizophrenia, or psychosis not otherwise specified. Females with ID represented 53% of the major depression group and 38% of the bipolar affective disorder group. Subjects of the latter group had significantly more mood-related symptoms, as well as functional impairments, compared to individuals from the other groups. Behavioural profiles of the bipolar group patients differed significantly from the other three groups adding to the evidence that bipolar disorder can be reliably identified in persons with ID. Mixed affective disorders, persistent affective disorders, dysthymia, cyclothymia, and their relation to gender has not been systematically studied in people with ID.

In the general population, several risk factors for affective disorder have been examined including stress, life events, low socioeconomic status, lack of social support, and female gender. A review of epidemiological studies on mental health problems of adults with ID showed that these risk factors are shared by people with ID, who may be further disadvantaged by their limited coping skills, experiences of discrimination, rejection, stigma, and abuse (Smiley 2005).

Using logistic regression analysis, Cooper et al. (2007) investigated factors associated with depression in persons with ID. Higher number of consultations with general practitioner in the last year, having experienced a life event in the last year, being a smoker, and being a female were all found to be associated independently with depression.

Biological risk factors in relation to women with ID experiencing mental health problems have not been studied in detail. However, syndrome-specific research (e.g. Down syndrome, Prader–Willi syndrome) has highlighted relevant hormonal differences between women with and without ID (Lunsky and Havercamp 2002). Both depression and menstrual cycles in woman with ID are associated with self-injurious behaviour (SIB). According to DC-LD, an onset of, or increase in, problem behaviours such as aggression or SIB are common in depressive episodes (Royal College of Psychiatrists 2001).

In a small study of records analysis of nine women with ID who exhibited SIB for six months, an attempt was made to determine any association between phases of the menstrual cycle and rates of SIB. Menstrual cycles were divided into four phases: (1) menses and early follicular phase; (2) late follicular phase; (3) early luteal phase; and (4) late luteal or premenstrual phase. Analysis showed that the highest frequency of SIB occurred in the first two phases: 43.5% during early follicular phase and 47.3% in the late follicular phase. Seven of the nine women manifested identical phase/SIB relations (Taylor et al. 1993).

Tsakanikos et al. (2007) examined 281 consecutive referrals to a community mental health and ID service in South East London for the impact of exposure to life events on mental health. Logistic regression analysis demonstrated that single exposure to life events was significantly associated with female gender, schizophrenia, personality disorders, and depression, with females being more likely to have been exposed to at least one life event. The authors did not find overall higher rates of depression in women with ID but found significantly higher rate of adjustment disorder in reaction to an identifiable stressor within the previous three months.

Lunsky (2003) recruited and interviewed 99 adults with borderline to moderate ID (51 men and 48 women) from community services in Ontario, Canada. Different scales and measures were used including one specific to depression. The ratings for women on the depression measures were higher than those of men. Informants’ ratings reported no gender differences. Women with higher scores in the depression measures reported significantly fewer coping strategies, lower socioeconomic status, and more stressful relationships.

Women with ID are more vulnerable to be abused than women in the general population and men with ID. There is ample research evidence demonstrating the high prevalence of sexual abuse among women with ID (McCarthy and Thompson 1997; McCarthy 2000; Lunsky 2003). In the general population a history of sexual abuse is well recognized as a significant factor for major depression, suicide attempts, personality disorder, substance misuse, and social anxiety (Nelson et al. 2002). In a United Kingdom (UK) case–control study, looking at the association between sexual abuse of persons with ID and psychological disturbance, more individuals from the abused group were meeting diagnostic criteria for depression and anxiety disorders as assessed by the PAS–ADD checklist (Sequeira et al. 2003). Other forms of abuse such as physical, emotional abuse, and neglect are prevalent among people with ID. However, no gender-specific studies explored in detail the effects of other types of abuse on the mental health of people with ID.

Loss of a family member, friend, or significant other, including staff members in residential homes, is a common experience for people with ID. There has been limited gender-specific research conducted in the area of bereavement and loss. However, when Hollins and Esterhuyzen (1997) compared the bereavement process in 22 females and 28 males with ID with a matched control group, they found a higher rate of depression, anxiety, and adjustment disorders in the bereaved group.

The association between pregnancy, birth, and the postpartum period and depression has not been widely explored in women with ID. General population studies of affective disorders associated with the postpartum period have not included those with diagnosis of ID. It is generally believed that pregnant women with ID have the disadvantage of poor social support which renders them more vulnerable to affective disorder. A large proportion of mothers with ID experience further traumatization by the removal of their children by child welfare agencies in cases of serious concerns about their ability to provide safe parenting.

Tymchuk (1994) investigated depression in mothers with ID and found significantly more depressive symptoms in comparison to a control group of women of the same socioeconomic background. National data from French and Belgian mother and baby unit admissions revealed that women with psychiatric disorder or ID remained hospitalized longer, improved less, were more often separated from their babies, or discharged with supervision, than women admitted with other diagnoses (Glangeaud-Freudenthal 2004). In the UK, the increased number of children of people with ID removed from the care of their parents is thought to be in breach of Human Rights legislation and this has led to calls for positive corrective action by the Department of Health (House of Lords 2007).

Suicide in adults with ID has been reported, but very few in-depth studies have been undertaken (Lunsky 2004; Merrick et al. 2006). Most of the literature agrees that suicide rates in people with ID are lower than those seen in the general population and suicide among those with more severe intellectual impairments is extremely rare. There is lack of evidence base on the relationship between gender and risk of suicide in people with ID. However, the majority of case studies of attempted and completed suicide in ID have focused on men, therefore further research is warranted (Lunsky and Canrinus 2005).

A recent study looked at affective disorder or related disorders in women with ID who are in contact with the criminal justice system. Lindsay et al. (2004) studied characteristics and outcome of female offenders with ID by examining referrals to a community service for offenders with ID in the UK during an 11-year period. They found that females accounted for 9% of referrals to the service: 61% of female offenders had suffered sexual abuse and 66% were identified as having a significant mental illness (schizophrenia, bipolar disorder, or major depression).

Autism is common in people with ID. Depression is probably the most common psychiatric disorder seen in individuals with autism. Lainhart and Folstein (1994) found an excess of females in their review of published reports of affective disorder in people with autism. However, Ghaziuddin et al. (2002) argue that it remains unknown whether depression is more common in females than in males with autism, because most of the existing literature reports on samples which are drawn from specialist clinics.

Diagnosing mental health problems in women with ID can be a complex process. In many ways, the assess-ment of this population follows the same principles of the psychiatric assessment for women without ID. Referral pathways, however, seem to be different as it is very rare for women with ID to initiate a mental health referral themselves. In most cases they rely on family or residential staff to identify the problem, with the most common reason for referral (for both genders) being behavioural disturbance. Subtle or slowly developing changes in mood, sleep, or appetite are less likely to be detected in busy residential homes. Subjective states of depressed mood or hopelessness require adequate cognitive and verbal skills in order to be expressed. Women with more severe ID are less likely to poses those skills; therefore reliance on behavioural equivalents or informants’ reports is necessary. The DC-LD criteria for depressive and manic episodes are shown in Boxes 33.1 and 33.2.

It is important to understand the mental health problems of both females and males with ID as a synthesis of

vulnerability, precipitating, and maintaining factors (biological, psychological, social, and environmental) This is a complex task and requires a coordinated multi-modal and interdisciplinary approach to assessment (O’Hara 2007).

The initial assessment interview is generally best conducted at the person’s home where observations can be made about the living environment and family or care home dynamics. The length and style of the interview must also be flexible to accommodate for memory or attention span problems, suggestibility, or acquiescence in some people with ID.

The issue of ‘diagnostic overshadowing’ is of great importance when assessing affective symptoms. Symptoms such as apathy, decreased verbal output, slowness, low initiative, and other depressive symptoms may be erroneously attributed to the ID, especially when little effort is made to document the person’s baseline of mood, affect, and functioning. Also, developmentally appropriate phenomena, such as talking to oneself or with imaginary friends, should be distinguished from psychotic phenomena, such as auditory hallucinations (Hurley and Silka 2003; Pickard and Paschos 2005).

A crucial aspect of the initial assessment is to exclude any physical cause for the affective symptoms such as endocrine and metabolic conditions, epilepsy, or other neurological conditions which are seen more commonly in people with ID. A full physical examination, blood investigations, imaging, and referral for other consultations should also be considered. A thorough assessment of physical health is more important for people with ID, who often have significant physical health needs (US Public Health Service 2002; Kerr 2004; NHS Scotland 2004). Several studies reported inequalities in accessing healthcare for people with ID as well as lower proportions of women with ID receiving cervical and breast screening compared to women without ID (DRC 2007).

It is expected that an assessment of a woman with ID should include a full psychiatric history, family and personal history, social history, relationships, menstrual history, pregnancies, and parenting experiences. A comprehensive risk assessment estimating the risk to self and/or others, as well as the risk of self-neglect, abuse, and exploitation, should also be a routine component of the assessment pathway.

In the past two decades, a number of screening, assessment, diagnostic, and monitoring instruments have been developed for people with ID (Mohr and Costello 2006). Although not a substitute for a thorough clinical assessment they can help increase the correct identification of mental health problems in this population.

The PAS-ADD checklist (Moss et al. 1998; Moss 2002) has recently had its psychometric properties independently assessed. It is a screening tool that can be used by untrained people to identify persons with ID with a possible psychiatric disorder. It contains 29 items concerning common psychiatric symptoms, split into five scales. These scales combined produce three total scores for: (1) affective/neurotic disorder; (2) possible organic disorder; and (3) psychotic disorder. The affective/neurotic disorder scale includes items on depression and hypomania. Sturmey et al. (2005) replicated the psychometric properties of the PAS-ADD in a sample of 226 persons with ID who were referred over a three-year period to a specialist service. Total scores on the affective/neurotic disorders scale had alpha values equal to or greater than 0.7. Internal consistency was found to be similar to that reported by Moss et al. (1998). There was also a significant difference in scores between participants who had depressive disorder and those with no diagnosis.

Instruments such as the PAS-ADD checklist cover a wide range of psychiatric conditions with affective disorders being only part of the schedule. However, the Glasgow Depression Scale for people with a Learning Disability (GDS-LD), was specifically developed for the assessment of affective disorders. The scale contains 20 items based on DC-LD diagnostic criteria. Focus groups (consisting of people with mild to moderate ID) data analysis provided the language often used to describe affect and emotions in this population. The developers of the scale demonstrated differentiation between depression and non-depression groups, correlation with the Beck Depression Inventory-II, good test–retest reliability (r=0.97) and internal consistency (Cronbach’s α=0.90), and 96% sensitivity and 90% specificity (Cuthill et al. 2003).

It is worth noting none of the diagnostic instruments reported in ID literature take into account any gender related issues.

The treatment of females with ID with psychotropic (including antidepressant) medication and relevant issues are discussed in depth on Chapter 34. Basic principles on best prescribing practices for people with ID include a thorough physical, psychological, social, and behavioural assessment before prescribing, and also a date for reviewing the need for medication (Einfeld 2001). To maximize effectiveness, treatment with medication should be part of a broader and holistic treatment plan. Polypharmacy should be avoided, and clear guidelines are needed regarding the use of ‘as required’ medication. Although there is a significant association between affective disorders (depression and hypomania) and challenging behaviour (Moss et al. 2000); this relationship is likely to be complex and where medication failed to control symptoms and behaviours, other interventions may be more effective, as shown in Case vignette 1.

Ms Mary is a 40-year-old woman with a moderate ID, severe autism, and behaviour disturbance including physical aggression and repeated self-injury. She has an additional diagnosis of bipolar affective disorder. She had spent her entire life in care settings. In the past year, her self-injurious behaviour deteriorated, she presented with depressed and irritable mood, poor sleep and appetite, and needed admission to an inpatient unit. On some weeks over 100 instances of difficult behaviours were documented in the unit. She was prescribed a depot antipsychotic injection, two anticonvulsants for mood stabilization, and benzodiazepines, both regular and ‘as required’. Four previous trials of antidepressants, lithium, and other antipsychotic medication did not improve her symptoms.

Following a year-long admission she was transferred to a secure small residential unit for people with autism and challenging behaviour. In just over two months, a significant improvement in her mood and behaviour was noted. There were no changes in her medication but all care staff in the unit had formal training in Positive Behaviour Support and special training and experience in autism. Ms Mary is now attending a day centre in the community and her medication is being reduced.

Large-scale provision of psychotherapy for people with ID has been slow to emerge, because of previous assumptions about the suitability of this group for talking treatments and the predominance of behavioural therapy. There is now a growing awareness that, with appropriate adaptations, most available psychological therapies can benefit people with ID, their families, and staff (Hurley 2005). Two recent meta-analyses of a small number of controlled studies have shown at least moderate benefit from engagement in a wide range of psychological treatments with schema-focused cognitive work appearing to have a lasting effect on a sample of people with moderate ID (Prout and Nowak-Drabik 2003; Royal College of Psychiatrists 2004).

Despite limited evidence base on the use of cognitive behavioural therapy (CBT) for people with ID (Dagnan and Jahoda 2006; Dagnan 2007), several models have been developed to treat depression and anxiety disorders, to teach assertiveness and social skills, and to inform anger management interventions. Role play and use of non-verbal materials, drawings, photographs, and picture storybooks are commonly employed to enhance CBT techniques.

There is some evidence that psychodynamic treatment can improve self-esteem and reduce distress and problem behaviours in persons with ID (Beail et al. 2005; Parkes and Hollins 2007). Like men, women with ID may find it difficult to express negative feelings, such as anger, towards people on whom they depend. It is theorized that verbalization of such unacknowledged feelings can result in therapeutic benefit. The effect the primary disability has on the person’s self-image (the ‘secondary handicap’) is also considered in psychodynamic therapy with people with ID (Hollins and Sinason 2000). Issues around sexuality, sexual abuse and other trauma, dependency needs, illness, and death can be difficult to discuss for many women with ID and a sensitive approach and a safe environment are required. Gender matching of the therapist should also be considered, especially when depression is linked to past experiences of abuse. Female-only support groups for women with ID who have been sexually abused and also providing support to access relevant mainstream counselling services have been found to be beneficial (Howlett and Danby 2007; Peckham et al. 2007).

Non-directive counselling or person-centred therapy can be a powerful approach for people with ID whose personal experiences are often ignored or discounted (Oliver and Smith 2005). Other forms of therapy such as dialectical behaviour therapy for people ID have also been described (Lew et al. 2006). Art, drama, and music therapy have all been used with people with ID and with people who have autism. The use of various media and communication alternatives is thought to allow choice and foster the growth of self-esteem. There is, however, a lack of controlled studies regarding these less structured interventions.

Presently, no particular model or approach seems to be superior and availability of local resources sometimes determines what type of therapy is provided. Although specialist skills will be required to work with some women with ID, a large number should be able to benefit from mainstream psychotherapy services (Royal College of Psychiatrists 2004).

Social and environmental risk factors for depression are well documented in the general population. People with ID may have an increased risk of depression because of higher rates of physical illness, socioeconomic adversity, experience of abuse and reduced life supports (Richards et al. 2001; Lunsky 2003; De Collishaw and Maughan 2004). Thus, a treatment package for females with ID and depression should consider a review of her housing situation, daily activities, and life and social opportunities. A safe environment and extra social supports may be necessary to achieve or maintain positive change in mental health.

Gender differences in patterns of service utilization and delivery have been documented among people with ID receiving specialist services; however, the focus of studies has not been solely affective disorders. Tajuddin, et al. 2004 carried out a retrospective note review of all admissions to a specialist ID mental health inpatient unit over a period of two years. People with mild and moderate ID made up over 90% of a sample of 72 people. More men with ID tended to be hospitalized than women with ID. The most common reason for admission for females with ID was behavioural disorder, followed by schizophrenia, personality disorder, depression, and bipolar affective disorder. In a review of a consequent referrals to a community mental health and ID specialist team, Tsakanikos et al. (2006) found that in a sample of 295 men and 295 women with ID and psychiatric problems, women with ID were more likely to be referred by their primary care physician, but men were more likely to be referred from generic mental health services. Finally, in a pattern similar to that seen in the general population, women with ID were found to be less likely to have forensic issues or to be placed in secure units (Beer et al. 2005).

Following de-institutionalization and the move to the community there has been little consensus as to who should provide services for people with ID and mental or behavioural disorders (Bouras and Holt 2004). As a general rule, the shape of services tends to reflect historical, political, and economic realities of the areas they serve. There has been a large geographical variation of the type, capacity, and functions of available services, sometimes even within the same country or region. Even though women with ID may be more likely to experience violence and abuse and become particularly vulnerable when they are mental ill, there have been no systematic efforts to address this issue. Services for people with ID and in particular inpatient provision have been criticized for continuing to be delivered in ‘gender blind’ manner (Kohen 2004).

There is little research in the area of gender differences in people with ID who experience affective disorders. Females with ID follow a pattern seen in the non-ID population and tend to experience higher rates of depression than males with ID. Their increased vulnerability to depression seems to be related to adverse life experiences, abuse and neglect, increased ill health, social isolation, and lack of support to meet culturally expected roles. The assessment of possible affective disorder in females with ID is similar to that for females without ID. Particular attention should be given to gender-specific issues and histories of abuse. The treatment should be holistic and take into account the need for a safe environment and space to talk about painful emotions. Despite a growing awareness of these issues, specialist ID services continue to be delivered with little regard to gender issues. Epidemiological studies on prevalence, risk, and protective factors for affective disorders will need to have a focus on gender to help understand better the mental health needs of women with ID. Providing that the right safeguards are in place, it is important that females with ID are included in trials of medication that could prove beneficial to them. In addition, more studies should concentrate on evaluating interventions and models of service delivery. The development of research networks which are not attached to a particular theoretical school and can evaluate different interventions based on holistic, gender-sensitive, and integrated models should be a future priority.