Women

In women after the menopause it is known that vaginal lubrication reduces and the vaginal epithelium thins, which can lead to pain during intercourse (dyspareunia) (Dhingra Reference Dhingra, De Sousa and Sonavane2016). These changes appear to be related to reduced levels of oestrogen, leading to vulvovaginal atrophy (Thomas Reference Thomas, Neal-Perry and Hess2018). Owing to the chronic and progressive nature of vulvovaginal atrophy it is recommended that early recognition and treatment provide the best symptomatic relief and reduction in dyspareunia and sexual dysfunction (Nappi Reference Nappi, Martini and Cucinella2019). First-line treatment is usually with local oestrogen therapy and sometimes systemic hormone therapy; other options include vaginal lubricants and pelvic floor training (Nappi Reference Nappi, Martini and Cucinella2019). Pelvic organ prolapse can occur in older women and adversely affect sexual function. Successful pelvic organ prolapse surgery can lead to significant improvements in sexual satisfaction and function (Geynisman-Tan Reference Geynisman-Tan, Kenton and Komar2018).

Men

The two main changes in sexual function with age in men are erectile dysfunction and ejaculatory dysfunction. It has been suggested that erectile dysfunction occurs in around 50% of men over the age of 70 and is mediated by psychological and physiological factors; the most important risk factors include age, obesity, smoking, coronary artery disease and depression (Krzastek Reference Krzastek, Bopp and Smith2019). The most common treatments for this disorder are lifestyle changes to reduce vascular risk factors (e.g. stopping smoking, losing weight) and oral vasodilating phosphodiesterase type-5 inhibitors, which act to increase blood flow to the penis (Krzastek Reference Krzastek, Bopp and Smith2019). Newer techniques include intracavernous injections of prostaglandin E1 and penile implant surgery (Rajpurkar Reference Rajpurkar and Dhabuwala2003). An even more novel treatment being explored is low-intensity extracorporeal shockwave therapy, which acts by promoting neovascularisation (Vardi Reference Vardi, Appel and Jacob2010). A study looking into potential age bias in men presenting to their doctor with erectile dysfunction found that, even when they presented with a clear psychosocial indication for the problem, doctors were still more likely to prescribe medication to older patients and to consider psychological treatment for younger patients (Gewirtz-Meydan Reference Gewirtz-Meydan and Ayalon2017).

As erectile dysfunction has reduced in recent years, thanks to the development of effective treatments, and clinicians are seeing an increase in ejaculatory dysfunction it has been suggested that an improved ability to achieve an erection does not necessarily translate into the ability to enjoy sex and achieve orgasm (Kleinplatz Reference Kleinplatz2008).

Parkinson's disease

Sexual dysfunction and Parkinson's disease are closely linked. The motor and non-motor symptoms of the disease both contribute to sexual dysfunction and reduced pleasure (Bronner Reference Bronner and Korczyn2017). The high burden of depression and anxiety in Parkinson's disease is included in this formulation. Sexual behaviours noted in some people with Parkinson's include increased preoccupation with sex and even hypersexuality, which are thought of as part of the non-motor syndrome of the disease (Bronner Reference Bronner and Korczyn2017).

It is important to keep in mind the link between dopaminergic medication and impulse control disorders, which can include impulsive sexual behaviours. The interference of motor symptoms with sex can be managed with the introduction of dopaminergic drugs, with adjustments made to the timing of the doses; similarly, adjustment of dopaminergic drug doses is the recommended initial approach to hypersexuality (Bronner Reference Bronner and Vodušek2011).

Sildenafil has been found to be effective for erectile dysfunction in men with Parkinson's disease and depression: improved erections were reported by 84.8% of participants in one study (Raffaele Reference Raffaele, Vecchio and Giammusso2002). Counselling and teaching specific techniques can help with delayed ejaculation and premature ejaculation, and antidepressants have been used for premature ejaculation (Bronner Reference Bronner and Vodušek2011).

Women can present with urge incontinence during intercourse, which can be addressed by emptying the bladder before sex and treatment of the overactive bladder (Bronner Reference Bronner and Vodušek2011).

Diabetes

Diabetes is commonly seen to affect sexuality. Ageing and long duration of diabetes are reported to reduce sexual functioning (in men more than women) and reduce the sexual quality of life of partners (Owiredu Reference Owiredu, Alidu and Amidu2017). In a survey of women with type 2 diabetes mellitus, up to 88% reported sexual dysfunction, including loss of interest, enjoyment or ability to participate in sex (Rahmanian Reference Rahmanian, Salari and Mohammadi2019). Sexual dysfunction is also widely seen in men with diabetes and can present in similar ways, with the addition of erectile and ejaculatory dysfunction (Owiredu Reference Owiredu, Amidu and Alidu2011). Mechanisms for sexual dysfunction in diabetes are multifactorial but include psychological, neurological, circulatory and iatrogenic causes (Rahmanian Reference Rahmanian, Salari and Mohammadi2019).

Chronic kidney disease

Chronic kidney disease is a common comorbidity in the older population and is also linked with sexual dysfunction. One study found that 70% of participants with end-stage renal disease receiving dialysis reported sexual dysfunction (van Ek Reference van Ek, Gawi and Nicolai2018). Pre-dialysis patients also frequently report sexual dysfunction (reduced frequency, anorgasmia, impotence, avoidance), with the most important factors being older age, hypertension, anxiety and depression (Guven Reference Guven, Sari and Inci2018).

Cancer

As cancer treatment improves there is an ever-growing population of long-term cancer survivors. Sexual dysfunction is a common problem following cancer treatment – prevalence estimates range from 40 to 100% – and encompasses a variety of problems, such as loss of motivation, poor body image and self-esteem, chronic dyspareunia and anorgasmia (Zhou Reference Zhou, Nekhlyudov and Bober2015). Specific questionnaires exist to aid assessment of sexual function in cancer survivors and they emphasise the importance of normalisation of these problems (Bober Reference Bober and Varela2012). Treatment options will vary depending on the specific dysfunction and, often, the type of cancer. Options include review by urologists, endocrinologists, clinical psychologists, liaison psychiatrists, sexual health counsellors and pelvic floor physical therapists (Zhou Reference Zhou, Nekhlyudov and Bober2015).

Cardiovascular disease

There is a strong link between cardiovascular disease and both erectile dysfunction and female sexual dysfunction. As the person ages we see a higher burden of cardiac disease and reduced cardiac function. Sexual activity (ranging from foreplay to intercourse) places strain on the cardiovascular system, increasing blood pressure and heart rate, often described as the equivalent of climbing two flights of stairs (Mornar Jelavić Reference Mornar Jelavić, Krstačić and Perenčević2018). Lifestyle changes and medical treatment of cardiac disease can improve erectile dysfunction and quality of life although, conversely, cardiovascular medications can exacerbate erectile dysfunction (Roushias Reference Roushias and Ossei-Gerning2019).

Antidepressants

The first-line treatment for depression is usually a selective serotonin reuptake inhibitor (SSRI). Sexual dysfunction is known to be associated with SSRI treatment: there is reported to be a twofold risk of hypoactive sexual desire and higher levels of erectile dysfunction and delayed ejaculation (Corona Reference Corona, Ricca and Bandini2009). It is suggested that the frequency of sexual dysfunction due to SSRIs is higher in men, whereas the intensity of the dysfunction appears to be higher in women (Montejo-González Reference Montejo-González, Llorca and Izquierdo1997).

The incidence of sexual dysfunction seen with venlafaxine (58–73%) is similar to that with the SSRIs, with lower incidence rates reported with mirtazapine (24.4%), nefazodone (8%) and moclobemide (3.9%) (Montejo Reference Montejo, Llorca and Izquierdo2001). It is suggested that serotonin reduces sexual drive and therefore the more strongly serotonergic medications appear to confer higher rates of sexual dysfunction (Gitlin Reference Gitlin1994). Mirtazapine, which is less purely serotonergic than the SSRIs, is therefore often the antidepressant of choice for people who experience sexual side-effects on SSRIs. A similar rationale is also used to support the lower incidence of sexual dysfunction with the tricyclic antidepressants (Gitlin Reference Gitlin1994). However, vortioxetine, a newer agent used for treatment-resistant depression that is thought to work via multimodal serotonergic action, has a low incidence of sexual dysfunction (Salagre Reference Salagre, Grande and Solé2018). In a randomised controlled trial vortioxetine did not show significantly different effects on sexual functioning in comparison with placebo (Jacobsen Reference Jacobsen, Zhong and Nomikos2019). Generally, the sexual side-effects of antidepressants are dose-dependent and reversible on switching medication, although there are rare reports that sexual side-effects persist even after discontinuation (Waldinger Reference Waldinger2015).

Antipsychotics

Sexual dysfunction is a side-effect also seen with many antipsychotics. The mechanism originally proposed involves dopamine blockade releasing the anterior pituitary gland from the effects of prolactin-inhibiting hormone (dopamine), resulting in increased production of prolactin, which can cause symptoms such as erectile dysfunction, amenorrhoea and reduced sex drive. Prolactin levels alone do not predict sexual dysfunction and the main pathway suggested is via antagonism of D₂ dopamine receptors in the mesolimbic pathway, leading to reduced libido (Downing Reference Downing, Kim and Procyshyn2019). As a result, reduced libido is seen in the majority (in one large study, 54.2%) of patients on an antipsychotic (Downing Reference Downing, Kim and Procyshyn2019). A summary of antipsychotics’ impact on sexual dysfunction suggested that risperidone caused the most problems, followed by first-generation antipsychotics (particularly haloperidol), then olanzapine, then quetiapine, with aripiprazole causing the fewest problems (Baggaley Reference Baggaley2008). Broadly speaking, ‘prolactin-inducing’ antipsychotics (first-generation agents, and the second-generation drugs risperidone, paliperidone and amisulpride) appear responsible for more sexual dysfunction than the ‘prolactin-sparing’ agents, although sexual side-effects are still commonly reported with some of these medications, for example clozapine and olanzapine (Stroup Reference Stroup and Gray2018).

As with antidepressants, the common approach to managing sexual dysfunction with antipsychotics would be first to reduce or switch the agent if this is possible. Aripiprazole acts as a partial agonist of dopamine receptors and appears to have a neutral effect, or indeed a reductive effect, on prolactin levels, resulting in avoidance of sexual dysfunction (Shah Reference Shah2013). It is therefore often the antipsychotic of choice to switch to if a person is experiencing sexual dysfunction on antipsychotic treatment and it is also used in some situations as an adjunct treatment where hyperprolactinaemia results from antipsychotic treatment. A recent systematic review was unable to make specific clinical recommendations owing to a lack of suitable studies but did identify small studies suggesting benefit of adjuvant sildenafil or adjuvant aripiprazole in reducing antipsychotic-induced sexual dysfunction (Allen Reference Allen, Baban and Munjiza2019).

Depression and anxiety

Sexual dysfunction is strongly associated with depression and is related to several depressive symptoms, such as low energy, low motivation, poor self-esteem, anhedonia and reduced libido. As already discussed, this is compounded by many antidepressants conferring a risk of sexual side-effects. It has been suggested that the prevalence of sexual dysfunction in people with depression is twice that in healthy controls and that recurrent depression may be more associated with sexual dysfunction than single episodes of depression (Montejo Reference Montejo, Montejo and Baldwin2018). A study that attempted to identify the baseline of sexual dysfunction in depressed individuals before treatment found that around one-third reported reduced interest in sex, with the most common dysfunction being reduced levels of arousal, followed by problems achieving orgasm or ejaculation (Thakurta Reference Thakurta, Singh and Bhattacharya2012).

The burden of sexual dysfunction appears to be higher in major depressive illness (76%) than in the common anxiety disorders, although there are still significant rates of sexual dysfunction reported in conditions such as obsessive–compulsive disorder (OCD) (50%) and generalised anxiety disorder (64%), with low desire being the most common dysfunction (Kendurkar Reference Kendurkar and Kaur2008). Fear of contamination during sexual activity is thought to be an important aspect of sexual dysfunction in OCD (Sabetnejad Reference Sabetnejad, Assarian and Omidi2016). Reduced sexual functioning, however, can still be found in people with OCD irrespective of fears of contamination or medication use (Vulink Reference Vulink, Denys and Bus2006).

A randomised controlled trial looked at response of sexual dysfunction in women with OCD to treatment with fluoxetine or cognitive–behavioural therapy (CBT) and found that those who received CBT showed significant improvement in areas of desire, arousal and orgasm though not in problems of reduced lubrication and dyspareunia (Sabetnejad Reference Sabetnejad, Assarian and Omidi2016). There was a reported reduction in satisfaction and sexual function in the group treated with fluoxetine, possibly related to sexual side-effects (Sabetnejad Reference Sabetnejad, Assarian and Omidi2016). The use of CBT more generally to target sexual dysfunction is an area where there is currently a lack of strong evidence to support formulation of guidelines (ter Kuile Reference ter Kuile, Both and van Lankveld2010). Both OCD and panic disorders are seen to be related to sexual dysfunction independent of medication use; therefore assessment of sexual functioning before psychotropic initiation could be an important aspect of treatment and prevention of further difficulties (Aksoy Reference Aksoy, Aksoy and Maner2012).

Eating disorders

Sexual dysfunctions are commonly seen in eating disorders and the psychopathology of these disorders is thought to be an important factor in perpetuating these problems (Castellini Reference Castellini, Lo Sauro and Lelli2013). The dysfunctions are likely to be multifactorial, including contribution from physiological changes related to low body weight and starvation (e.g. lethargy, amenorrhoea), comorbid depressive symptoms, problems with self-esteem and perceived body image (Castellini Reference Castellini, Lelli and Lo Sauro2012). There is suggestion that the mechanisms of sexual dysfunction may vary between anorexia nervosa and bulimia nervosa: in one study, dysfunction was found to correlate with body mass index in anorexia, whereas the correlation found in bulimia was with depressive symptoms measured by the Beck Depression Inventory (Gonidakis Reference Gonidakis, Kravvariti and Varsou2015).

Although treatment of sexual dysfunction in the eating disorder population has not been studied in detail it is thought that treatment focusing on body image, binge eating and emotional eating could improve sexual function (Castellini Reference Castellini, Lelli and Lo Sauro2012). Psychotropic treatment of the eating disorder and any comorbid depressive illness would also appear to be a sensible approach to improving underlying dysfunctions, keeping in mind the difficulty with sexual side-effects.

Schizophrenia

Sexual dysfunction in schizophrenia is complex (Box 1): it can be related to symptoms of the condition (particularly negative symptoms), antipsychotic medication, comorbid physical health conditions, stigma and other psychosocial factors (de Boer Reference de Boer, Castelein and Wiersma2015). A study of drug-free men with psychosis in India showed a prevalence of 25% for sexual dysfunction in those engaged in sexual activity; dysfunction was related to both older age and later age at illness onset (Ravichandran Reference Ravichandran, Gopalakrishnan and Kuruvilla2019). Other studies have suggested prevalence of dysfunction between 30 and 60% in drug-free patients with psychosis and prevalence as high as 80% in a more general population of men with schizophrenia (Ravichandran Reference Ravichandran, Gopalakrishnan and Kuruvilla2019). In a rural Chinese population with schizophrenia 71.3% reported sexual dysfunction and this was associated again with old age and with burden of negative symptoms (Huang Reference Huang, Hou and Ng2019). Although there is a paucity of research into this area it has also been suggested that loss of interest in sex in people with schizophrenia is associated with advancing age, female gender, cardiovascular medication, negative symptoms and lower sexual self-efficacy (self-confidence and self-control in sexual experiences) (Bianco Reference Bianco, Pratt and Ferron2019). It is not clear whether treatment of the psychotic disorder confers an improvement in dysfunctions: a study of men with schizophrenia in remission still showed high levels of dysfunction (between 78.4 and 97.1%) across five domains of sexual functioning (Kheng Yee Reference Kheng Yee, Muhd Ramli and Che Ismail2014). Another aspect of sexuality studied in schizophrenia is risky sexual behaviour, which refers to unprotected sex with risk of unwanted/unintended pregnancy and transmission of sexual diseases. A prevalence of 39.4% was reported in a study of 429 people with schizophrenia in Ethiopia, with associated factors including male gender, younger age, positive symptoms and substance misuse (Negash Reference Negash, Asmamewu and Alemu2019).

Bipolar affective disorder

Bipolar affective disorder can be associated with both hyposexual disorders and hypersexuality, often related to the polarity of the current episode of the illness. Sexual dysfunction during bipolar depression can be thought of as similar to the dysfunction seen in a unipolar depressive illness, and as in that illness there are also reports of residual sexual dysfunction in euthymic patients (Montejo Reference Montejo, Montejo and Baldwin2018). Residual sexual dysfunction has been shown to affect medication adherence in clinically stable individuals with bipolar disorder so is important to keep in mind when assessing the patient (Grover Reference Grover, Ghosh and Sarkar2014). Sexual distress and dissatisfaction have been found to be higher in people with bipolar disorder than in the general population and higher rates of sexual desire are seen in these patients in comparison with those with unipolar depression (Sørensen Reference Sørensen, Giraldi and Vinberg2017). Stigma again appears to play an important role in bipolar disorder: a US study found that rates of marriage were lower in adults with bipolar disorder (32.8%) than in the general population (55.7%), and 52.9% of patients felt that stigma affected their relationship success (Jackson Reference Jackson, Kolikonda and Yeruva2018). Mania-induced hypersexuality and risky sexual behaviour is well-known but understudied in this population, as are lower intensity increases in sexual behaviour and the impact of cycling mood on relationships (Kopeykina Reference Kopeykina, Kim and Khatun2016). Guidelines for treating acute manic episodes are well established but again there is little specific guidance on hypersexuality and the recurring problems of sexual side-effects of medication.

Discrimination against LGBT residents

Residents themselves have often reported positive attitudes towards sexuality in old age but when it comes to sexual activity, attitudes tend to be more negative, in part due to beliefs about perceived ‘appropriateness’ (Mahieu Reference Mahieu and Gastmans2015). Among LGBT older adults, a study of perceptions of discrimination in retirement care facilities showed that 73% believed that discrimination existed and the sources of perceived discrimination included administration, care staff and other residents (Johnson Reference Johnson, Jackson and Arnette2005). There has been a presumption of heterosexuality in older adults and this is suggested to be linked to discrimination sometimes experienced by LGBT residents and the conflict that signs of affection between LGBT residents can cause in long-term care settings (Addis Reference Addis, Davies and Greene2009). One study found that lesbian and gay older men delayed entry into long-term care, possibly because of these perceptions but also because they saw long-term care as a real threat to their independence (Claes Reference Claes and Moore2000).

Cognitive impairment and dementia

Cognitive impairment and dementia in long-term care give rise to ethical issues regarding consent and capacity. Sexual expression, both verbal and physical, varies greatly in dementia and too often is only thought of as a subset of agitated or inappropriate behaviours (Makimoto Reference Makimoto, Kang and Yamakawa2015). This perception also influences the limited research on sexuality in residents with dementia in care homes, and there is a focus on problems faced by staff rather than a more holistic approach (Elias Reference Elias and Ryan2011). Achieving a balance between a person with dementia's desire for sexuality and the staff's role to protect can often cause conflict and challenging behaviour (Ehrenfeld Reference Ehrenfeld, Tabak and Bronner1997). The lack of national guidelines and policies can lead to inconsistent approaches and local variation (Makimoto Reference Makimoto, Kang and Yamakawa2015). A common theme in long-term care settings is a lack of staff education on issues such as sexuality, risk assessment and assessment of capacity to consent to a sexual relationship (Elias Reference Elias and Ryan2011). Therefore, in the environment of the care home it can be difficult to separate a cognitively impaired resident's attempts to fulfil their sexual needs from illness-related sexual disinhibition (Box 2).

Antidepressants

Antidepressants are commonly used to treat sexual disinhibition, often in part because of their better safety profile than options such as antipsychotics. There exist case studies to support the use of a variety of antidepressants, including SSRIs, trazodone, mirtazapine and even the tricyclic antidepressant clomipramine despite its potential to increase confusion in people with dementia (De Giorgi Reference De Giorgi and Series2016).

Cholinesterase inhibitors and beta-blockers

Cholinesterase inhibitors are often used to treat behavioural and psychological symptoms in dementia but the evidence to support their efficacy in sexual disinhibition is more conflicted (Joller Reference Joller, Gupta and Seitz2013).

The beta-blocker propranolol has been used because of its side-effects of reduced sexual drive and sexual dysfunction, which are hypothesised to be due to its reduction of adrenergic drive (De Giorgi Reference De Giorgi and Series2016).

Antipsychotics

In the UK, the antipsychotics risperidone and haloperidol are licenced for the short-term treatment of aggression in Alzheimer's disease but their use must be balanced against the known increased risk of strokes and cardiovascular events in this population. Although most of the literature on antipsychotics in dementia focuses more broadly on challenging behaviour there are case studies showing successful use in sexual disinhibition, for example quetiapine (Prakash Reference Prakash, Pathak and Munda2009), aripiprazole (Nomoto Reference Nomoto, Matsubara and Ichimiya2017) and haloperidol (Kobayashi Reference Kobayashi2004). The first-generation antipsychotic benperidol is no longer used in clinical practice to treat psychotic illnesses but does still see some use owing to its licence for treating ‘deviant antisocial sexual behaviour’ (Joint Formulary Committee 2019). Use of this drug in people with dementia appears more based on anecdotal experience, with no recent trials supporting its use. The evidence for use of benperidol originates from studies in the 1970s of sexual deviancy in prisoners (Field Reference Field1973).

Anticonvulsants

There is often an overlap between medications used to treat severe agitation in dementia and those trialled in sexual disinhibition, possibly reflecting the lack of strong evidence in treating both. Anticonvulsants have been historically used to treat challenging behaviour and some studies have looked at their use in sexual disinhibition. Carbamazepine has been used to treat severe agitation in dementia and there are case studies that show successful use of the anticonvulsant in treating sexual disinhibition (Freymann Reference Freymann, Michael and Dodel2005; Poetter Reference Poetter and Stewart2012).

Anti-androgens and progestins

Another long-standing option in the limited armoury for treating sexual disinhibition has been anti-androgens. The anti-androgen cyproterone acetate has been used in the forensic setting to treat offenders who have committed sexual offences, as it might reduce sexual desire, frequency and enjoyment (Lippi Reference Lippi and van Staden2017). It is understandable that there can be some discomfort in using anti-androgens in people with dementia, particularly when much of the original evidence base comes from forensic settings, where it has been referred to by some as ‘chemical castration’. There have, however, been case studies that show potential efficacy of these agents (Haussermann Reference Haussermann, Goecker and Beier2003). The progestin medroxyprogesterone has also been suggested to treat sexual disinhibition in dementia via a reduction in testosterone levels, and successful case studies exist for the intramuscular use of this medication (Light Reference Light and Holroyd2006).

‘Chemical castration’ and ethics

The term ‘chemical castration’ might be used more broadly to describe all of the psychotropics discussed in this section, not just the anti-androgens and progestins. There are ethical issues when prescribing medications for people with advanced dementia who lack capacity to consent to treatment. There should always be consideration of the person's best interests and the current level of risks. All the medications discussed have side-effects and risks to the person, particularly the antipsychotics, which are known to increase the risk of stroke and mortality in people with dementia. This needs to be balanced with the potential risks to others from the sexually disinhibited behaviour and the risks to the person, who may well also be in a very vulnerable situation.