University of Groningen Women’s lifestyle and sexual function Karsten, Matty

Women’s lifestyle and sexual function

Karsten, Matty

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10.33612/diss.125792427

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Karsten, M. (2020). Women’s lifestyle and sexual function: the effects of a preconception intervention in

women with obesity. University of Groningen. https://doi.org/10.33612/diss.125792427

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CHAPTER 8

8

The first part of this dissertation focused on the effects of a preconception lifestyle intervention in

women with obesity and infertility. The effects were evaluated in terms of short- and long-term

changes in diet and physical activity, and we also examined the biopsychosocial determinants

that underlie successful lifestyle change. The second part of this dissertation evaluates the

long-term effects of a lifestyle intervention on sexual function, the impact of polycystic

ovary syndrome (PCOS) on mental health and sexual function, and the effects of traumatic

experiences and symptoms of post-traumatic stress disorder (PTSD) on sexual function and

pelvic floor overactivity. In the current chapter, the findings and implications of this dissertation

are discussed and integrated.

M A I N F I N D I N G S

The preconception lifestyle intervention improved diet and physical activity in the 6 months

of the intervention (chapter 2). Also, women in the intervention group had a lower energy

intake 5 years after the intervention. This long-term effect was most pronounced in women who

were successful in losing weight during the intervention itself, as a lower energy intake was

also reflected in a lower BMI in these women (chapter 4). Determinants of successful lifestyle

change and lifestyle intervention program completion were: not having received previous

dietetic support, higher external eating behaviour, and a high stage of change (chapter 3),

which are important to consider in the development of personalised interventions aimed to

optimize treatment success.

Women in the intervention group reported better overall sexual function five years after the

intervention (chapter 5). Furthermore, we found that women with PCOS did not have poorer

sexual function, or more anxiety and depressive symptoms, but they did have lower mental

health-related quality of life compared to women without PCOS with similar BMI and fertility

status (chapter 6). Lastly, we found that women who developed PTSD symptoms after exposure

to interpersonal trauma had a higher pelvic floor activity without evident effects on sexual

function (chapter 7).

The obesogenic environment

Worldwide, obesity is a problem of increasing size.

_{The ‘obesogenic environment’ contributes}

importantly to the increasing levels of obesity and hence the rise of obesity related chronic

health problems.

_{The obesogenic environment has been defined as the ‘sum of influences}

that the surroundings, opportunities, or conditions of life have on promoting obesity in

individuals or populations’.

_{This environment makes people gain weight more easily and also}

makes sustained weight loss difficult.

_{In most obese individuals, attempts at weight loss often}

show a pattern of initial improvement followed by a gradual decay over time. Within our own

study we saw a similar pattern of improvement and decay. The increasing body of evidence

suggesting this temporary effect of lifestyle interventions aimed at individuals has fuelled the

debate about the efficacy of lifestyle interventions as a central solution for the obesity epidemic

and suggestions are made that in addition to individual approaches the focus may need to shift

towards also including alterations in the obesogenic environment.

In the United states average food intake, calculated from food supply adjusted for wastage,

has increased since the 1970’s. The magnitude of this increase is sufficient to explain the rise

of the prevalence of obesity.

_{A similar phenomenon of the obesogenic environment is}

currently seen in developing countries like China, largely influenced by the economic growth

of the country.

_{Factors such as an increased portion size, variety and availability of foods}

offered, eating out, fat and sugar content of the diet and the availability of processed foods

have contributed to the rise in obesity over the past 40 years.

_{Increased urbanisation}

led to rapid changes in the built environment in terms of walkability, availability of bicycle

paths, transportation opportunities, neighbourhood safety, number of parks in the area and

industrialisation in the workplace, all-together leading to more sedentary lifestyles over the

past decades.

In the current obesogenic environment, the only lasting effective intervention to treat obesity in

individuals is bariatric surgery. On average, weight loss in the first year after bariatric surgery is

37% and only about one third of the weight loss is regained over 10 years after surgery.

_By

comparison, lifestyle interventions generally result in 5 to 9% weight loss

_{and almost all of the}

weight is generally regained after 3 to 5 years.

_{However, bariatric surgery is not without}

side effects, in 20% of the cases adverse events occur varying from gastrointestinal symptoms

(~17%), nutritional and electrolyte abnormalities (~17%) and death (1%).

In order to curb the obesity epidemic, we need to look for other potential solutions to treat

individuals with obesity but also to prevent people, especially the next generation

_{, from}

becoming obese. Changing the obesogenic environment into a healthier alternative may

provide solutions to prevent obesity. There are various examples of such environmental changes,

such as a tax for sugar sweetened beverages in Mexico that led to a 7.6% reduction of sugary

drinks in the first two years

_{, the revenues are now invested in installing water fountains across}

schools in Mexico.

_{This Mexican sugar-tax has translated into moderate reductions in weight}

and waist circumference two years after introduction

_{and has been expected to translate into}

a 2.5% reduction in obesity prevalence within 10 years.

_{Another example of the beneficial}

effects of an environmental change can be found in Japan. A nation-wide exercise routine, the

15-minute ‘rajio taisō’ workout, is broadcasted four times a day on national NHK radio since

the 1920’s.

_{During work-days, children at schools and employees in all socioeconomic}

8

classes across the country are encouraged to participate in this routine, which is expected

to account for the Japanese healthy life expectancy

_{and lowest obesity rates (3.5%)}

alongside their healthy traditional (Washoku) diet.

Personalised interventions

Next to the environmental factors that are necessary in obesity management, it remains largely

unknown why only a small number of people achieve sustained weight loss through lifestyle

interventions.

_{In this dissertation we found that women who were previously counselled by a}

dietician before the start of the intervention were 50% less often successful in their weight loss

attempt. These women, who had one or more previous unsuccessful attempts at losing weight,

might need a different type of support than was offered during our lifestyle intervention,

such as help from a psychologist to overcome mental challenges and improve self-efficacy

in weight loss.

_{People with psychological problems, such as depression, anxiety, trauma}

and eating disorders, have more difficulties in controlling their food consumption, performing

regular exercise routines and hence weight management.

_{In these individuals food may be}

used as a coping mechanism in negative emotions when sad, stressed, lonely or frustrated.

This suggests that psychological support could be a promising addition to lifestyle intervention

programs for individuals with obesity.

Furthermore, some of the determinants of successful lifestyle change we identified can be used

to develop effective interventions. A determinant of successful lifestyle change was a higher

level of external eating; eating in response to external food cues such as the sight and smell

of food.

_{Since eating styles seem important in success of lifestyle change, these styles could}

therefore be assessed at the start of interventions to guide women based on their individual

eating style. Also women with a higher readiness to change and a higher level of self-efficacy

at the start of the intervention were more likely to successfully change their lifestyle. This is in

line with a review that shows that high levels of self-efficacy and self-regulatory skills predict

weight control, physical activity, and dietary intake in overweight and obese adults.

_These

determinants can also be assessed in other intervention studies or clinical practice prior to

individualised support or to enhance baseline levels of self-regulatory skills and self-efficacy

before the start of the intervention in women who have a low baseline level of these skills.

Trauma, stress and obesity risk

Traumatic experiences can contribute to the development of obesity

_{, mainly when PTSD}

symptoms are present.

_{The effects of traumatic stress on the body may to some extent resemble}

the effects of chronic emotional stress on obesity development. Chronic elevated stress levels, as

determined by higher hair cortisol levels, are associated with a higher waist circumference and

BMI

_{, which are both also risk factors for cardiovascular diseases and diabetes mellitus.}

Stress that is perceived as uncontrollable has been linked to a change in eating patterns through

a sensitivity towards reward in the consumption of salient and hyper palatable foods (‘comfort

food’).

_{Stress can trigger neurobiological brain adaptations in metabolic-, reward- and}

stress pathways

_{, with a varying sensitivity between individuals that is partly genetically}

determined.

_{Together with the availability of rewarding foods in the obesogenic environment}

these pathways can promote compulsive eating behaviour and weight gain in cases of chronic

stress.

_{When aiming at lifestyle changes in obesity, we should therefore also incorporate}

these biopsychosocial mechanisms, by reducing stress and increasing mental well-being.

This might increase effectiveness of lifestyle interventions in obesity. In this dissertation we

did not evaluate chronic stress nor traumatic experiences as determinants of lifestyle change.

However, there are indications that the women, who participated in our lifestyle intervention

and had experienced traumatic events during their childhood, had an unhealthier lifestyle and

more stress symptoms.

_{Upcoming mindfulness-based stress reduction (MBSR) interventions}

show promising results in stress reduction and short-term weight loss.

_{MBSR therefore may}

be incorporated, alongside the assessment of trauma exposure, and in lifestyle interventions

aimed at reduction of obesity to provide a more holistic, psychosomatic and personalized

treatment approach.

Interdisciplinary psychosomatic approach

The WHO defines health as a ‘complete state of physical, mental and social well-being, and

not merely the absence of disease or infirmity’.

_{To address this, psychosomatic healthcare}

including interdisciplinary healthcare teams may be useful to achieve more integrated,

holistic, and high quality care.

_{An interdisciplinary approach, with a greater exchange of}

experiences and specialised knowledge seems necessary to optimize treatment success.

Additionally, patient engagement in the development of interventions may lower the burden

of research, increase the relevance, quality, validity and translation into clinical practice.

From a patient’s perspective, insight into their condition, a feeling of empowerment and support

can be gained from their involvement.

An example of such integrated care can be found in the management of wounds, wherein

an interdisciplinary approach involving: physicians, surgeons, dermatologists, diabetologists,

nurses, podiatrists, nutritionists, social scientists, rehabilitation staff and the family of the patient,

led to more effective wound care.

_{Calls for interdisciplinary healthcare approaches have also}

recently been made in the field of cardiovascular disease.

_{The LIFEstyle intervention aimed to}

take a personalised approach and used motivational counselling to improve lifestyle changes,

but was delivered with a somatic oriented approach by health professionals. Personalised

8

interventions constructed through an interdisciplinary approach, such as a collaboration

between nutritionists, psychologists, physicians and the patient, may increase effectiveness by

influencing underlying causes affecting food intake and physical activity patterns.

Examples of integrating psychological methods in lifestyle interventions in the treatment of obesity

may involve cognitive behavioural therapy (CBT)

_{, which is currently used to treat cognitions}

and coping patterns in obesity

_{by affecting both feelings and behaviours. Furthermore, an}

effective trauma treatment called Eye Movement Desensitization and Reprocessing (EMDR)

that reduces the burden of a traumatic event

_{, may be used in women with obesity and PTSD}

symptoms.

All this suggests that an interdisciplinary approach might be effective to improve obesity

treatment.

Personalised interventions in the obesogenic environment

Although personalised interventions could optimize the efficacy and response during lifestyle

interventions, they may only partly solve the obesity intervention puzzle.

_{When people}

successfully change their lifestyle and lose weight but remain in the same obesogenic

environment that stimulates unhealthy dietary practices and sedentary behaviour, maintaining

lifestyle changes is challenging.

_{Therefore, both a personalised approach and changes in the}

obesogenic environment are needed.

For lifestyle interventions, it is desirable that the government invests in (research) initiatives

that contribute to knowledge about adopting and sustaining a healthy lifestyle. Recently, state

secretary Blokhuis, of the Dutch Ministry of Health, Welfare and Sports in the Netherlands,

granted 5 million euros towards research investigating how to optimally improve lifestyle.

Also, another promising development is the ambition of the joint Health Foundations in the

Netherlands to achieve the Healthiest Generation by 2030.

_{The Healthy Generation aims at}

an integrated approach by changing society, social- and personal environments to create the

conditions to support healthy choices.

Lifestyle change and sexual function

The LIFEstyle intervention led to positive long-term changes in sexual function, partly mediated

by an increase in physical activity. A recent review

_{examined short and long-term effects}

of exercise on female sexual function and showed that the short term effects of exercise are

beneficial for sexual function, possibly caused by the increased sympathetic nervous system

activity and endocrine factors. It is thought that the short-term response of the sympatric nervous

system is directly increasing blood flow, heart rate and blood pressure, which resemble the

later stages of female sexual (genital) arousal. Exercise also has a positive effect on mood

stimulating serotonin activity in the brain, which increases tryptophan in the blood, and by

the release of endorphins.

_{This direct impact of exercise on mood may contribute to an}

indirect effect of exercise on sexual satisfaction.

The long-term effects of regular exercise preserve autonomic nervous system flexibility, thereby

improving cardiovascular health and mood. Regular exercise is beneficial for cardiovascular

health by keeping the autonomic nervous system and endothelial function healthy in protecting

it from age-related decline.

_{Improvements in cardiovascular health also enhance}

sexual function by enhancing vaginal blood flow, important for genital vasocongestion and

thus vaginal lubrication.

_{Furthermore, long-term exercise positively influences body}

image

_{, which positively affects sexual functioning.}

_{Improved body image is related to a}

greater sexual function in women, it appears that women profit more from exercise to improve

their body image than men

_{, mainly due to the aesthetic societal ideal and improvements in}

psychological health.

_{Although the exact causal pathways have not been elucidated the}

evidence suggests that exercise has positive effects on sexual function and should therefore be

stimulated.

The women in our study were obese, and obesity is negatively related to cardiovascular health,

mood and body image.

_{In our study, weight change alone did not mediate the effect of}

the lifestyle intervention on sexual function. Many scientists have suggested that the causal

direction is from obesity to a reduced sexual functioning. However, given the cross-sectional

nature of most studies, a reverse causal relationship wherein sexual dysfunctioning is leading

to obesity, caused by distress, increased food intake and reduced physical activity, is also

conceivable.

The beneficial effects of long-term regular physical activity on sexual function in women with

obesity therefore need to be studied further. Moreover, the beneficial immediate and long-term

effects of physical activity on sexual function can be communicated to women to motivate them

to change their lifestyle.

PCOS and obesity and the effect on mental- and sexual wellbeing

In literature

_{and in the recently published international PCOS guideline}

_{, PCOS has}

been associated with higher levels of anxiety and depression, and a worse mental and sexual

health. In the analysis of our cohort, anxiety and depression, physical quality of life and sexual

function in obese infertile women with PCOS seem more related to obesity than to PCOS status.

However, PCOS status was associated with an impaired mental quality of life. According to

literature, obesity negatively affects both mental health

_{and sexual function}

_{, and both}

mental health and sexual function decreases proportionally with an increased BMI.

_In

the current PCOS guideline

_{few studies on both topics have used matched comparisons}

8

between PCOS and non-PCOS women with respect to BMI and fertility characteristics. Most

studies

_{compare a PCOS group with obesity and infertility with women with a normal}

weight without infertility, which could distort the currently described effects attributed to

PCOS, in the guideline. In our study we were unable to investigate the effect of these separate

PCOS phenotypes, such as anovulation, clinical of biochemical hyperandrogenism and/or

polycystic ovaries separately

_{, on mental health and sexual function. Future studies should}

therefore investigate which specific phenotype(s) of PCOS relate (most) to mental health and

sexual function outcomes.

Interdisciplinary approach in female sexual dysfunction

The interdisciplinary psychosomatic approach described in the treatment of obesity earlier,

can also apply to female sexual dysfunction and mental wellbeing in obese women. The

pathophysiological consequences of obesity in women, such as e.g. the dysregulation of

oestrogen and androgen production and a poorer endothelial function might play a role in

female sexual function.

_{Furthermore, biological mechanisms in women with obesity}

dysregulate the hypothalamic pituitary-adrenal (HPA) axis that alters cortisol levels, which

has been linked to depression.

_{An impaired mental health is one of the most important}

predictors of female sexual dysfunction.

_{Furthermore, body dissatisfaction in women with}

obesity is both linked to depression

_{and a decreased sexual function.}

_This

psychosomatic interplay is described in women with PCOS in outcomes of both mental health

and sexual function.

_{In our study we did not find an effect of PCOS on anxiety and}

depression, physical quality of life and sexual function in women with a comparable high BMI.

However compared to women in a reference population with normal weight, both mental

health and sexual function seem impaired in obese women with and without PCOS in our study.

And since women with PCOS often have a higher BMI

_{an interdisciplinary psychosomatic}

approach may therefore improve sexual function, mental wellbeing and obesity outcomes. The

need for an interdisciplinary psychosomatic approach in both domains of mental health and

sexual function, is currently also recommended in the international evidence based guideline

for the assessment and management of PCOS.

Another psychosomatic relationship described in this dissertation was the association between

PTSD symptoms and pelvic floor overactivity. This somatic manifestation of psychotrauma is

also seen in literature, wherein patients who report higher overall PTSD symptoms more often

report physical symptoms as well.

_{Sexual assault or abuse survivors frequently present}

with somatic chronic pelvic pain

_{and irritable bowel syndrome (IBS).}

_{A dissociated}

self-image

_{, intrusive-}

_{, or hyperarousal}

_{symptoms may predict somatisation after a traumatic}

event. PTSD development is fairly common after interpersonal trauma exposure, on average

10% of women up to 25% after sexual trauma.

_{Depending on the patient’s request for help, a}

psychosomatic cooperation can be deployed. When a patient reports pain during intercourse,

pelvic floor function can be assessed by a physiotherapist and traumatic experiences can be

queried after which a psychologist or sexologist can be involved. Vice versa, when the patient

reports PTSD symptoms during psychological treatment sexual functioning and pelvic floor

overactivity can be queried and patients can be referred. Psychologists therefore need to work

together with gynaecologists or physicians and pelvic floor physiotherapists to interdisciplinary

threat both the psychological and somatic symptoms in women. Screening for pelvic floor

overactivity may therefore need to be accompanied by screening for PTSD and sexual

problems in women with interpersonal trauma, and vice versa depending on the discipline and

the patient’s request for help.

Interconnectedness: a network approach in research

In several chapters within this dissertation a complex interplay is seen between psychological,

social, and biological factors. This complex interplay is seen in the relationships between: PTSD

and pelvic floor overactivity, the psychosocial factors involved in successful weight loss, and

the relation between PCOS, obesity, mental health and sexual function.

These phenomena may be best studied in a network approach

_{, in contrast to our}

predominantly linear approach in this dissertation. The network approach has gained

considerable attention and recognition in the recent years, and is a method of conceptualizing

disorders wherein the symptoms are causally connected in a symptom network.

_{In this}

symptom network the disorders result from the causal interplay between the biological,

psychological and social symptoms (e.g. traumatic experience, feeling depressed, overeating),

that may involve feedback loops (e.g. a person may overeat to forget about their weight

problems caused by overeating).

_{A network approach can identify the symptoms central}

in the network and can explain why certain disorders co-occur more often than others.

A network approach may provide insight in: comorbidity, prediction, and clinical intervention,

and may built upon the traditional research approach, which is currently only based on the

idea that symptoms are manifestations of the underlying factor instead of a complex causal

system.

_{This may add to the development of personalised interventions and treatments}

through studying the networks of individuals.

_{Targeting multiple psychosomatic factors in}

interventions studies may have more impact than trying to tackle one single factor at a time and

may help to understand implications for treatment in all associated disciplines in psychosomatic

medicine.

_{Such network approaches are becoming realistic possibilities with recent}

data-gathering and modelling techniques.

_{Although those techniques are currently available, the}

main challenge is the accessibility of research data on such large scale, which may require a

mentality change in the field of research to provide open access to all available data.

8

C O N C L U S I O N S

The research in this dissertation shows that physical, psychological and social factors in the field

of lifestyle, overweight and sexual function are interrelated. Future interventions are therefore

likely to show greater effects if they focus on several of these interrelated factors. We may need

a more holistic approach within health care and research settings to translate research results

into policy and practice.

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