Relationship of health-related quality of life to symptom severity in diabetes mellitus: a study in Trinidad and Tobago.

Our objective was to estimate the effect of greater symptom severity in diabetes mellitus on measures of health-related quality of life in a cross-sectional design in 35 government primary care health centres in Trinidad. Data were gathered on 2,117 subjects with clinical diabetes and analysed for 1,880 (89%). For each scale of the short form 36 (SF-36) questionnaire (a generic measure of health-related quality of life), scores were presented by quartile of symptom severity, measured using the Diabetes Symptom Checklist. Mean (SD) SF-36 scores were 44 (10) for the physical component score (PCS) and 45 (12) for the mental component score (MCS). Greater severity of diabetic symptoms was associated with lower scores on each of the subscales of the SF-36. Comparing lowest and highest quartiles of DSC score, the adjusted difference in PCS was -11 (95% confidence interval -12 to -9) and for MCS -16 (-18 to -14). Our results provide standardised data for health related quality of life in relation to severity of illness from diabetes, these might be used to aid the evaluation of relevant interventions.