Investigation for secondary causes is recommended in early onset hypertension. However, obesity is associated with higher blood pressure (BP), so investigation for alternative secondary causes may not be necessary in all obese patients. We sought to define a rational approach to investigation across strata of age, body mass index (BMI) sex and race, based on BP distributions in the US National Health and Nutrition Examination Surveys 2005 to 2016. The majority (71% [95% CI, 59%-79%] and 64% [95% CI, 57%-69%] by European and US definitions respectively) of early onset hypertension cases were attributable to BP distribution shifts accompanying obesity and male sex. Male versus female sex, BMI>40 versus 18.2<BMI≤25 and Black versus White race were accompanied by adjusted mean systolic BP differences of 9 (95% CI, 8-9) mm Hg, 13 (95% CI, 12-15) mm Hg, and 3 (95% CI, 2-4) mm Hg respectively. Normal BMI women above the age cutoff for investigation were less likely to be hypertensive than obese younger men meeting current investigation criteria (P<0.001). Targeting investigations to combinations of sex, BMI, and age with low hypertension prevalence would reduce the number investigated while still identifying as many secondary cases. Limiting investigations to patients with a BP exceeded by ≤5% of their respective sex/BMI/age category would give investigation thresholds ranging from ≥130/≥80 and ≥140/≥90 for normal BMI women and men, respectively, at age 20 to 30 years, to ≥160/≥100 and ≥170/≥105 for women and men with BMI ≥40 at age 30 to 40 years. In conclusion, we propose refined strategies for investigation of early onset hypertension in the context of an obesity epidemic.
Keywords: blood pressure; body mass index; hypertension; obesity; prevalence.