Validation of self reported diagnosis of hypertension in a cohort of university graduates in Spain

• Published in: BMC public health 2005-09, Vol.5 (1), p.94-94, Article 94
• Main Authors: Alonso, Alvaro, Beunza, Juan José, Delgado-Rodríguez, Miguel, Martínez-González, Miguel Angel
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Blood Pressure Determination - standards; Cohort Studies; Diet, Mediterranean; Educational Status; Female; Humans; Hypertension - diagnosis; Hypertension - epidemiology; Male; Middle Aged; Prevalence; Risk Factors; Self Care - standards; Spain - epidemiology; Surveys and Questionnaires; Universities
• ISSN: 1471-2458; 1471-2458
• DOI: 10.1186/1471-2458-5-94

The search for risk factors of hypertension requires the study of large populations. Sometimes, the only feasible way of studying these populations is to rely on self-reported data of the outcome. The objective of this study was to evaluate validity of self-reported diagnosis of hypertension in a cohort of university graduates in Spain. The Seguimiento Universidad de Navarra (SUN) Study is a cohort of more than 15,000 university graduates in Spain. We selected a random sample of 79 cohort participants who reported a diagnosis of hypertension and 48 participants who did not report such diagnosis (76% participation proportion). Then, we compared information on the self-reported diagnosis of hypertension and hypertension status as assessed through two personal blood pressure measurements and an interview. Additionally, we compared self-reported and measured blood pressure levels with intraclass correlation coefficients and the survival-agreement plot. From those 79 reporting a diagnosis of hypertension, 65 (82.3%, 95% CI 72.8-92.8) were confirmed through conventional measurement of blood pressure and the interview. From those 48 that did not report a diagnosis of hypertension, 41 (85.4%, 95% CI 72.4-89.1) were confirmed as non hypertensives. Results were similar among men and women, but were worse for overweight and obese individuals, and for those with a family history of hypertension. The agreement between self-reported and measured blood pressure levels (as a continuous variable), as estimated by the intraclass correlation coefficient, was 0.35 for both systolic and diastolic blood pressure. Self-reported hypertension among highly educated participants in a cohort study is a relatively valid tool to assess the hypertensive status of participants. However, the investigators should be cautious when using self-reported blood pressure values.