Introduction: Establishing the burden of undiagnosed CVD risk factors is critical to monitoring public health efforts related to screening and diagnosis.
Objective: To assess the proportion and determinants of undiagnosed diabetes, hypertension, and hypercholesterolaemia, among overweight or obese adults.
Methods: A sample of 1200 participants aged 35-64 years with a BMI ≥25 kg/m2 was selected from the Colombo district. Data were collected through a questionnaire, anthropometry, blood pressure measurement, and blood sampling for fasting plasma glucose, HbA1c, and lipid profile. Undiagnosed diabetes, hypertension, and hypercholesterolaemia were defined as fasting plasma glucose ≥126 mg/dL or HbA1c ≥6.5%; systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg; total cholesterol ≥240 mg/dl respectively, in a person without a previous diagnosis. Multiple logistic regression analyses were carried out to identify determinants.
Results: The prevalence (95%CI) of diabetes was 28% (25.5, 30.5), hypertension, 33.4% (30.7, 36.1) and hypercholesterolaemia, 31.9% (29.2, 34.5). The proportion of undiagnosed diabetes was 13.8% (11.9, 15.8), undiagnosed hypertension 11.3% (9.5, 13.1), and undiagnosed hypercholesterolaemia 17.8% (15.6, 19.9). Undiagnosed cases accounted for almost half of all diabetes cases, one-third of all hypertension cases, and more than half (56%) of all high cholesterol cases. The key determinants for undiagnosed CVD risk were: male sex, low or middle income, rural residence, and relatively younger age.
Conclusion: CVD screening programmes should be tailored to target populations based on these determinants and provide basic diagnostic facilities in all health centres. The 'proportion undiagnosed' in the population may be a useful indicator to evaluate their effectiveness.
Keywords: undiagnosed diabetes, undiagnosed hypertension, undiagnosed hypercholesterolaemia, cardiovascular disease risk, screening.