As part of the Medical Outcomes Study, that determined the impact of nine different chronic illnesses upon HRQL, Stewart et al. used the Short Form (SF-20) of the General Health Survey to evaluate HRQL ratings in 9385 patients, 844 of whom had diabetes (92% were type 2 diabetics and 44% had one or more physician-reported complications). Diabetic patients in this study reported lower HRQL scores than control patients with other chronic conditions. Also, after controlling for sex, age, income and education, subjects with diabetes reported significantly lower scores on all summary scales (physical, role, social functioning, health perceptions) except for mental health. Moreover, gastrointestinal disorders had a more negative impact on HRQL than all other conditions with the exception of heart disease. Others have reported similar findings.
Jacobson et al. assessed HRQL in 240 diabetic patients (54% were type 2 diabetics) and controlled for age, marital status, education, illness duration and severity of complications. Compared with patients with type 1 diabetes, patients with type 2 diabetes reported less of an impact of diabetes and fewer worries about their illness on the diabetes-specific quality-of-life scale, the DQOL, used in the Diabetes Control and Complications Trial (DCCT), as well as better social functioning on the SF-36.
Gastrointestinal complications of diabetes and HRQL
A study of diabetic patients undergoing transplantation indicated that, of all the factors likely to compromise HRQL, the single most important one was gastrointestinal dysfunction. Drenth and Engel suggested that symptoms of nausea, vomiting, bloating/distension, early satiety and abdominal pain likely all play a role in this perception. Talley et al. evaluated quality of life using the SF-36 and gastrointestinal symptoms in 209 outpatients and 892 community subjects with diabetes; quality of life scores were decreased in diabetics with gastrointestinal symptoms, and decreased markedly with increased numbers of gastrointestinal symptoms. Moreover, gastrointestinal symptoms were significantly associated with poorer quality of life after adjusting for age, gender, smoking, alcohol use and type of diabetes.
Siddique et al. evaluated upper gastrointestinal symptoms and quality of life using the SF-12 in 483 community subjects with self-reported diabetes and 422 age- and gender-matched controls in the USA. They observed that upper gastrointestinal symptoms were associated with more impaired physical and mental health summary scores; on the other hand, individuals with diabetes and no gastrointestinal symptoms had quality of life scores similar to healthy subjects. Early satiety and nausea were the strongest predictors of physical and mental health score differences, respectively, in those with and without diabetes.