Have People Treated With Antihypertensives Been Diagnosed With Hypertension? A Cross-Sectional Study in Stockholm, Sweden.

Purpose: Studies on antihypertensive treatment are important, as hypertension remains the major risk factor for cardiovascular morbidity and premature death. However, antihypertensive medicines are also used for other conditions, and the use of these medicines as a proxy for a diagnosis of hypertension might lead to misclassification in pharmacoepidemiological studies. This study aimed to investigate to what extent people dispensed antihypertensive medicines have been diagnosed with hypertension.

Methods: Cross-sectional study with data covering all healthcare and all dispensed prescriptions of antihypertensive medicines 2019 and diagnoses recorded 2015-2019 from the Stockholm Region, Sweden. Multinomial logistic regressions were used to assess the probability of having hypertension concerning age, sex, and antihypertensive drug class.

Results: A total of 386 860 individuals were included, 49% men, 12% incident users, and 80% of all had a recorded diagnosis of hypertension. In 73% of incident users, only one antihypertensive drug class was dispensed, as compared to 36% of prevalent users. A total of 38% of incident users and 9% of prevalent users had none of the diagnoses selected for the study recorded in any health record during 5 years. Prevalent and older users over the age of 65 from high (50%-79%) to very high (80% and more) probability of a recorded diagnosis of hypertension. Patients on antiadrenergic agents, high-ceiling diuretics, aldosterone antagonists, or beta receptor blockers had a lower probability of having a recorded diagnosis of hypertension than patients dispensed angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or calcium channel blockers.

Conclusion: Most patients dispensed antihypertensive medicines have a diagnosis of hypertension. However, caution is needed using data on dispensed medicines to classify incident antihypertensive users and younger patients as having a diagnosis of hypertension.