Chronic pain is recognized as an important public health concern that poses significant economic and social problems (
1). Pain provides the most common physical symptoms in primary care. It is considered a huge burden of suffering and discomfort for patients that reduces the quality of life (QOL), causes social disability, reduces health care, and causes substantial social and economic costs (
2). In addition to deteriorating QOL, the literature shows that long-term pain leads to comorbidity of mental and physical diseases (
3). Despite numerous physical and psychological problems that patients with chronic pain face, researchers believe that adaptation to disease and its acceptance are essential in the disease treatment and can affect individuals’ psychical and social conditions (
4). Adaptation to disease refers to maintaining a positive attitude toward the disease and the world with many problems. Psychological adaptation includes seven subscales: attitudes toward work environment, family environment, illness, development of family relationships, social environment, and psychological disorders in sexual relations. Studies have shown that the strongest predictor of health services compared to other variables is psychological adaptation. However, nonadaptation to disease is characterized by anxiety, depression, helplessness, and behavioral problems (
5). Chronic pain affects the patient and their family and social life (
1). As the quality of marital relationships is somewhat correlated with physical health (
6), researchers define marital relationships’ quality as a subjective and global assessment of the relationship and related behaviors (
7). The quality of marital relationships is a multidimensional concept and includes various marital relationships such as adaptation, satisfaction, happiness, cohesion, and commitment. Expressing high satisfaction with the relationship, having positive attitudes toward the spouse, and low levels of hostility and negative behaviors indicate a desirable marital quality. Studies show that marital relationships’ quality affects individuals’ physical health status and occurrence of myocardial infarction, metabolic syndrome, and mortality (
8). A review of the literature shows that high-quality marriages directly affect psychological well-being and may play an influential role in subsequent stressors in life, such as caring for a partner with a disease (
9). Providing care for a sick spouse affects the caregiver in a variety of ways and may have adverse effects on personal interests, social life, QOL, and psychological status (
10). Researchers believe that good marital relationships are the basis of good family functioning, and if the family base is not sufficiently strong, it causes divorce and thus physical and mental problems (
11). Preliminary reports on the family life of the patient with chronic pain have shown that they often face widespread marital and sexual problems (
12). Sexual issues are among the most crucial issues in married life, and adaptation in sexual relations is considered an element affecting happiness (
13). One of the hot topics in sexual relations is sexual self-esteem, which is one of the dimensions of public self-esteem and refers to individuals’ emotional response to their thoughts, feelings, and sexual behaviors (
14). Numerous studies have shown that chronic illnesses and diseases can lead to reduced marital adjustment and sexual, emotional, and communication problems between couples (
15,
16).
When sexual self-esteem is impaired, life satisfaction, the ability to experience pleasure, interaction with others, and the ability to form intimate relationships with others are damaged. If damage to sexual self-esteem is severe, it can cause severe dysfunction (
17). In other words, sexual self-esteem and subsequent sexual satisfaction affect both the quality of married life and the individual’s overall health in various dimensions. Researchers have shown that dissatisfactory sex and the resulting physical and psychological stress disrupt health care and reduce capabilities, abilities, and creativity (
18). Therefore, sexual self-esteem, directly and indirectly, affects individuals’ physical, psychological, and social health. Considering the importance of marital quality and its impact on various aspects of women’s lives, especially sexual self-esteem, an attempt has been made to explain the role of marital and sexual variables in women’s psychological adaptation to disease in patients with chronic pain. Since less research in Iran has focused on the importance of marital relationships and sex variables in these patients, this study investigated whether sexual self-esteem could mediate the relationship between marital quality and psychological adaptation to disease in women with chronic pain.