Knowledge of risk of developing diabetes mellitus among siblings of Type 2diabetic patients

Aims We set out to investigate the extent to which siblings of diabetic sub jects perceived themselves likely to develop Type 2 diabetes mellitus (DM) when offered screening tests. Methods Nondiabetic siblings, aged 35-74 years, of Type 2 diabetic patients who were more than 35 years old at diagnosis had fasting plasma glucose me asured in a study to determine heritability of diabetes. Questionnaires ass essing perceived likelihood of developing, seriousness and knowledge about diabetes were completed. Logistic regression assessed factors predicting pe rceptions of diabetes risk. Results Factors predicting diabetes on screening were male sex, increasing age and body mass index (BMI) greater than or equal to 30. Eighty-nine per cent of 540 eligible siblings completed questionnaires. Thirty-eight per ce nt saw themselves at increased risk of diabetes and 34% thought diabetes a serious problem. Predictors of perceiving an increased likelihood of develo ping diabetes were female sex, age 35-54 years vs. 55-74 years and having a parent with diabetes. BMI did not affect perceptions of likelihood. Conclusion A perception of reduced vulnerability to diabetes may occur due to unawareness of risk or minimization of risk. Feelings of invulnerability may affect emotional response to a subsequent result. It is not known whet her providing more information about the risk of developing diabetes prior to screening would affect outcomes.