The aim of this seed is to identify the relative impact of various cost drivers on the increasing cost of hypertension treatment among US elderly. Different drivers may have different implications for cost containment. Thus far, the researchers have analyzed the National Diagnosis and Therapeutic Index (NDTI)-patient encounter data and are now working on the pharmacy dispensing data set to determine the relative changes in aggregate costs over time according to four key cost drivers: population of patients with hypertension seen in primary care, number of drugs prescribed per patient, selection of drugs by drug class and price of drugs by drug class. Following this the researchers will compare analyses for patients 65 year and older versus younger.
Data collection has been completed, and the researchers are in the stages of final analysis. Preliminary results suggest that over the past 15 years there has been relative stability in the proportion of elderly patients who have visited primary care offices. The number of antihypertensive drugs prescribed these patients at visits has increased, and the proportion with well-controlled blood pressure has also increased. Trends in antihypertensive prescriptions identify increased prescribing of ACE-inhibitors, angiotensin receptor blockers, and beta-blockers and flat or decreased prescribing of diuretics and calcium channel blockers. Of note, sub-set analyses indicate persistent disparities in blood pressure control by race/ethnicity. Remaining analyses include full link-up with NPA data on exact drug dosing and costs.
Two manuscripts are in preparation. The first will focus on the cost-drivers of antihypertensive medication prescribing among elderly US patients and compare these to the cost-drivers among non-elderly patients. The second will focus on disparities in antihypertensive prescribing and adequate blood pressure control among elderly hypertensive patients who are White vs. Black or Hispanic, with notation of persistent disparities in these even among the sub-sets of elderly hypertensive patients at very high risk for cardiovascular morbidity and mortality due to their co-morbid chronic kidney disease.