Studying the Impact of Illness on Lifestyle

 “Illness intrusiveness” is a term coined to explain the disruptive effects of an illness on a patient’s lifestyle. Patients with anorexia nervosa (AN) have lots of first-hand experience with this. AN’s chronic course delivers a tsunami-like onslaught of serious medical complications, interruptions of social and family life and careers, as well as significant psychiatric problems.

Drs. Jacqueline C. Carter, Carmen Bewell, and Gerald M. Devins, of Toronto General Hospital, the University of Toronto, and York University, Toronto, designed a study to compare the level of illness intrusiveness between AN patients and patients with other chronic and medical complications, and also to compare the effects on the two subtypes of AN, binge/purge (AN-BP) vs. restricting (AN-R) (J Psychosom Res 2008; 64:519). Finally, the researchers investigated the changes in the level of illness intrusiveness among AN patients after completion of specialized inpatient treatment.

Measuring 13 domains of life

Dr. Carter and colleagues used the Illness Intrusiveness Rating Scale (IIRS), which measures the degree to which an illness and/or its treatment interferes with 13 domains involved in quality of life. Among the quality of life indicators are satisfaction with life, depressive symptoms, self-esteem, and marital satisfaction. They also used the Eating Disorders Examination in the study. According to the authors, little if anything is known about how AN compromises quality of life compared to other chronic physical and psychiatric conditions.

Study subjects

The study participants were a consecutive series of female patients admitted to the inpatient eating disorders program at Toronto General Hospital between 2000 and 2006. The final group included 121 women with a mean age of 25.4 years and a mean body mass index (BMI) of 15 mg/kg.2 The mean duration of illness was 6.6 years, and the mean age at onset was 18.7 years. Most patients were students, and 84% were single. Fifty-two of the women met DSM-IV criteria for AN-BP subtype, and the remaining 69 women (57%) had AN-R subtype.

Ninety-five percent of the women completed questionnaires when they were admitted to the program, but discharge data were collected only from the 70 patients (58%) who successfully completed the program and who achieved a BMI of at least 20. One-third of the women who completed program had AN-BP, and of these 20 (87%) were free from binge-eating and purging at discharge. Of the 70 who completed the program, 88% provided discharge data, and 85% participated in the 3 month follow-up assessment.

AN compared with other psychiatric and medical illnesses

Without exception, the IIRS scores for women with both AN subtypes at admission were significantly higher than scores reported by women with other psychiatric disorders, including anxiety disorders, bipolar disorder, and schizophrenia.

Changes in patient scores after inpatient treatment

Treatment had a statistically significant effect on all patients. The mean total IIRS score decreased (improved) both from admission to discharge and from discharge to follow-up. At follow-up, total IIRS scores for women with AN were similar to those of women with other psychiatric illnesses but higher than those of women with other medical conditions.

Dr. Carter and her colleagues noted real differences among the women by subtype of AN. And, they reported that the higher levels of intrusiveness among women with AN suggested that AN patients perceive their illness to be highly disruptive in a number of areas of their lives, even more so than patients with other serious medical and psychiatric illnesses in whom motivation to change is not usually an issue. This suggested that lack of motivation to change in AN is not due to a lack of awareness of how greatly the disease interferes with valued activities and interests. Instead, it might be related to a tendency to focus more on the valued aspects of the eating disorder, such as thinness and control of overeating. Thus, in many cases, the perceived positive aspects of the eating disorder (for example, self-control) may outweigh the lifestyle disruptions from the illness.

Treatment and its effect on the two AN subtypes

Illness intrusiveness improved significantly after inpatient treatment, and the gains were maintained 3 months later. However, the researchers found that the improvement occurred only in the restricting subgroup. Among AN-BP patients, IIRS scores improved from pre-treatment to post-treatment but did not continue to improve during follow-up. Whereas women with AN-R reported significant reductions in illness intrusiveness into their relationships and personal development as well as work, life, active recreation, and health, women with AN-BP did not report a similar pattern.

The reasons for this difference may lie in the nature of binge eating and purging, according to the researchers. The authors noted that binge-eating and purging symptoms are more salient than food restriction; binge-eating and purging is time-consuming, often expensive, and typically occurs in secret. In addition, these symptoms result in a variety of medical consequences. Half of the women with AN-BP in the study began to have problems with binge-eating and purging during follow-up even though there were no significant weight changes.

The authors also found that the extent to which anorexia nervosa interferes with one’s marital and sex life does not improve with specialized inpatient treatment for the eating disorder. Women with anorexia nervosa often report problems with sexual intimacy.  Problems relating to their sexual partners are likely related to poor body image and may also reflect the high prevalence of childhood sexual abuse in this population.

Clinical implications

The authors feel the findings from their study may have important clinical implications. First, treatment of AN-BP patients might be improved by helping patients develop new interests and by maintaining an active focus on valued activities. Next, in appropriate cases, it may be helpful to provide sex therapy or couples therapy for AN-BP patients either during or after specialized treatment for AN.