Abstract P048: Effect of Hurricane Katrina on Medication Adherence and Blood Pressure among Hypertensive Veterans
Background. An increase in cardiovascular events and blood pressure (BP) has been reported in the aftermath of major natural disasters. This increase may be due to acute psychological stress, physiologic suffering, or lack of appropriate healthcare services in these situations.
Objectives. Using retrospective cohort data from the Veterans Administration, we examined the impact of Hurricane Katrina on medication adherence and BP control among 1000 hypertensive patients from New Orleans, Louisiana compared to 1000 patients from an area not affected by the hurricane, Alexandria, Louisiana.
Methods. Antihypertensive medication refills were identified from electronic pharmacy records, and blood pressure readings recorded during routine examinations were extracted from electronic patient data. Adherence to antihypertensive medications was assessed using the medication possession ratio (MPR), a standard method of quantifying refills. MPR was classified as low (<0.80) or high (≥0.80). Multivariable-adjusted regression methods were used to examine change in BP from the 6 months before the hurricane to 6 months after the hurricane.
Results. In the year before Hurricane Katrina, the proportion of patients with low MPR was similar for patients in New Orleans (11.8% [106 of 902]) and Alexandria (11.3% [105 of 931], p-value=0.75 for group differences). In the year following the hurricane, there was a significant increase in the proportion of New Orleans patients with low MPR (24.1% [155 of 643]), compared to Alexandria (11.2% [94 of 838], p-value<0.001 for group differences). The unadjusted mean (95% Confidence Interval) increase in BP from the pre-Katrina to post-Katrina period was 6.6 (4.7, 8.3) mmHg systolic/5.7 (4.6, 6.8) mmHg diastolic and 2.1 (0.8, 3.5) mmHg systolic/1.2 (0.4, 2.0) mmHg diastolic among patients in New Orleans and Alexandria, respectively (p-value<0.001 for group differences). After adjustment for age, race, pre-Katrina BP, and post-Katrina MPR as a continuous variable, the mean increase in BP remained significantly higher among patients in New Orleans at 5.9 (4.3, 7.6) mmHg systolic/4.5 (3.5, 5.5) mmHg diastolic, compared to those in Alexandria where mean increase was 2.0 (0.8, 3.2) mmHg systolic /1.5 (0.7, 2.2) mmHg diastolic (p-value < 0.001 for group differences).
Conclusion. BP significantly increased among hypertensive veterans in New Orleans as compared to Alexandria after Hurricane Katrina. This increase was only in part explained by changes in medication adherence. Future disaster planning should provide veterans with a rapid and easily-available method of accessing medications and health services and should anticipate increased BP and potential cardiovascular events among patients with hypertension.
- © 2012 by American Heart Association, Inc.