[4] The development of the Strange Situation task in 1965 by Ainsworth and Wittig allowed researchers to systematically investigate the attachment system operating between children and their parents.
Infant behaviour tended to follow patterns, leading to the development of three attachment categories: Secure, Anxious-Avoidant, and Anxious-Resistant.
Three main methods of measuring adult attachment have been developed, with slightly different purposes and variable amounts of concordance between them.
"[12] Working models are representatives of the cognitive schema, or psychological structure (often unconscious), which underlie the different attachment classifications.
Bartholomew and Horowitz proposed and verified a working model based on two dimensions; the view of the self (self-esteem) and the view of others (sociability)[12] In 2012 Maunder and Hunter[17] combined the internal working model with the attitudes, behaviours and emotional expression of the different styles to create a prototype based classification that included severity of insecurity.
This model was designed to be clinically useful, allowing healthcare providers to identify and predict the behaviours of patients whose attachment systems were activated by pain and illness.
Accordingly, attachment styles influence patient perception of illness, health care utilization, medication compliance and treatment response.
[1][18] While strong social support has been linked to greater resilience to stress and lower medical morbidity and mortality, the mechanism behind this association is poorly understood.
[20] Larger scale evidence comes from a large American survey of self-reported attachment styles and physical illness conducted by McWilliams and Bailey.
They found that people with anxious-resistant (dismissive) styles of attachment reported vague, non-specific symptoms more often, and those with anxious-preoccupied classification had a higher rate of inflammation-based illnesses.
This prospective study was particularly important because of the difficulty assigning causation in the often observed relationship between chronic pain and insecure attachment.
[25][26] Bowlby predicted that insecure attachment would be a risk factor for mental health difficulties based on ineffective, or overly rigid, strategies for reducing distress and maintaining psychological resilience.
Researchers have looked at both cortisol response to stress (CRS) and CRA to determine if attachment anxiety and avoidance underlie individual differences in HPA activity.
[44] The finding that those with fearful attachment would show small cortisol reactivity in response to a stressor may seem counterintuitive but is in line with the predictions of stress researcher Bruce McEwen, who hypothesized that frequent early stressors in life would cause an initial hyper-reactivity in the HPA axis that would over time become pathologically sluggish as the individual ages, leading to greater overall cortisol release and less adaptive responsivity.
One way which insecurely-attached individuals may try to regulate their distress is by using strategies or behaviours that are attractive for their short term relief, but may have deleterious risks over years like eating, drug use or risky sex.
In a survey of 356 primary care patients in Toronto, rates of smoking, harmful drinking, and obesity, were all found to be highest in those with the most severe anxious and avoidant attachment.
[62] In a study of young adult females, drug use was one of several risky behaviours that occurred more frequently in those with insecure attachment along with unsafe driving and sexual practices.
In terms of conscious motivations for sex, attachment anxiety is related to many attachment-related motivations including using sex for desire for emotional closeness, reassurance, self-esteem enhancement, stress reduction, the experience and exertion of power, elicitation of caregiving from a partner, protection from a partner's anger or bad moods.
Attachment avoidance has consistently been linked to poorer treatment adherence[20][68][69] and more recently to no shows in scheduled follow up appointments.
For those high in attachment anxiety, they would have higher distress when faced with an illness, less perceived ability to manage it on their own, and thus visit health care services more frequently to try to attain security.