Morbidity and mortality risk among patients with screening-detected severe hypertension in the Malmo Preventive Project

Objective: Screening of hypertension has been advocated for early detection and treatment. Severe hypertension (grade 3 hypertension) is a strong predictor for cardiovascular disease. This study aimed to evaluate not only the risk factors for developing severe hypertension, but also the prospective morbidity and mortality risk associated with severe hypertension in a population-based screening and intervention programme. Research design and methods: In all, 18 200 individuals from a population-based cohort underwent a baseline examination in 1972-1992 and were re-examined in 2002-2006 in Malmo, Sweden. In total, 300 (1.6%) patients with severe hypertension were identified at re-examination, and predictive risk factors from baseline were calculated. Total and cause-specific morbidity and mortality were followed in national registers in all severe hypertension patients, as well as in age and sex-matched normotensive controls. Cox analyses for hazard ratios were used. Results: Men developing severe hypertension differed from matched controls in baseline variables associated with the metabolic syndrome, as well as paternal history of hypertension (P < 0.001). Women with later severe hypertension were characterized by elevated BMI and a positive maternal history for hypertension at baseline. The risk of mortality, coronary events, stroke and diabetes during follow-up was higher among severe hypertension patients compared to controls. For coronary events, the risk remained elevated adjusted for other risk factors [hazard ratio 2.31, 95% confidence interval (CI) 1.22-4.40, P = 0.011]. Conclusion: Family history and variables associated with metabolic syndrome are predictors for severe hypertension after a long-term follow-up. Severe hypertension is associated with increased mortality, cardiovascular morbidity and incident diabetes in spite of treatment. This calls for improved risk factor control in patients with severe hypertension.