Quality of life in relation to comorbidity among diabetic patients followed for three years in Swedish primary health care.

The aim of this study was to follow health-related quality of life (HRQOL) in diabetic subjects over a three-year period in relation to their medical situation. Forty-eight subjects 42-81 years of age in 1992 were identified as those responding to the HRQOL questionnaire on both occasions from a larger study of 341 diabetic patients in 1992 and 413 in 1995 in Stockholm County. Age- and sex-matched controls were taken from randomly collected samples of the general Swedish population. HRQOL was assessed by the SWED-QUAL (the Swedish Health-Related Quality of Life Survey). Medical data were extracted from medical records at community health centres. Pearson's correlation coefficient for SWED-QUAL results over time exceeded 0.60 for seven of the ten scales (p < 0.001). A significant difference between 1992 and 1995 was found only for "Physical functioning" (p < 0.01). The general deterioration in health seen in medical records was accompanied by a decrease in the "Sleep problems" scale. In conclusion, worse outcome was noted only for "Physical functioning", while deterioration in health according to medical records was related to a worse outcome with respect to "Sleep problems". However, as the sample was small and not randomly selected, the results should be interpreted with caution and need confirmation in further studies.