Quality of life in type II diabetes: evaluation and applications.

Issues of quality of life (QOL) have often been considered for patients with insulin-dependent diabetes mellitus (IDDM, type I diabetes). Daily blood glucose monitoring and need for self-injections pose an obvious threat to the attainment of QOL, as does concern about long term complications. In contrast, non-insulin-dependent diabetes mellitus (NIDDM, type II diabetes) may be considered less severe, and has attracted less research interest. In fact, type II patients may also be aware of their heightened vulnerability to physical complications, as well as being affected by the need for heightened vigilance and attention to diet and exercise regimens. Issues associated with the theory and development of QOL measures are discussed largely in relation to type I diabetes and cancer. Generic measures have advantages in allowing comparisons to be made across different disease groups, and are, therefore, often favoured by health economists. In contrast, disease-specific scales are more sensitive to changes in treatment regimens, and may therefore be the instruments of choice in evaluating new treatments. In general, there has been less attention paid to how the meaning of QOL changes throughout the lifespan, and our review of the literature therefore emphasises a developmental perspective when considering the processes through which diabetes may affect an individual's QOL. Measures which, at the least, take into account changes in meaning of QOL throughout the lifespan need to be developed.