Incidence of Ischemic Colitis in Treated, Commercially Insured Hypertensive Adults: A Cohort Study of US Health Claims Data

Abstract

Study results indicate that the treated hypertensive patients may have a higher risk of pIC compared with non-hypertensive populations. The quantity of antihypertensive agents prescribed may contribute to IC more than treatment duration.

Antihypertensive Drugs, Hypotension, and Ischemic Colitis

“…This was probably not reached for the aliskiren monotherapy and dual combination therapy groups. This point is incidentally well underlined by the authors in the discussion: ''interpretation of the data is limited by the wide confidence intervals, which resulted from the facts that pIC [probable ischemic colitis] events were rare and the aliskiren-exposed sample was small'' [1]. Despite the huge size of the database, with more than 70 million unique patients, 2.3 million in the aggregate hypertensive study cohort, and wider inclusion criteria for aliskiren than for other antihypertensive agents, the authors should not exclude that aliskiren could raise the risk of ischemic colitis compared with other antihypertensive agents, because of a lack of statistical power.…”

“…In this issue of the journal, Hines et al [1] report incidence rates of ischemic colitis in treated hypertensive adults in the USA, with a focus on aliskiren, a direct renin inhibitor. While these investigators are to be commended for assessing such a large dataset (2,356,226 hypertensive patients), they provide no clear explanation for the focus on aliskiren.…”

“…Thus, estimation of the incidence rate of ischemic colitis among treated hypertensive adults, with a specific focus on aliskiren, as conducted by Hines et al [1] is a topic of high interest. Unfortunately, the authors present only crude incidence rates of ischemic colitis for overall, incident, and prevalent patients according to some treatment groups.…”

“…Hines et al [1] used three methods to calculate incidence rates, with wide variations in the results. In the main method of calculation, patients were classified according to the drugs taken within 30 days after inclusion for hypertension, irrespective of the duration of drug exposure, drug switch, or drug add-on during the follow-up (intent-to-treat analysis).…”

“…Although the paper by Hines et al [1] brings important information on the general risk of ischemic colitis in treated hypertensive patients, further research is needed to differentiate the attributable risk of hypertension from that of its treatment, which of the available antihypertensive drugs, drug classes, and combinations have a higher risk of ischemic colitis, and whether the higher risk is constant during exposure or mainly at the beginning of exposure (initiation or switch). One of the best designs to address these questions is that used by Yadav et al [12], applied to a hypertensive population with a cohort to estimate the overall age-and sex-adjusted incidence rate of ischemic colitis in this population, and a nested case-control analysis, or self controlled design [13], to estimate crude and adjusted ORs for risk factors, antihypertensive drugs, classes, and combinations commonly used in medical practice.…”