Switching of antihypertensive drugs among 93 286 Chinese patients: a cohort study

Abstract

Antihypertensive drug switching induces substantial public health costs. This cohort study evaluated factors associated with switching of antihypertensive agents 180 days after the first date of prescription among ethnic Chinese patients. We included all adult patients aged > or =18 years, who had paid at least two consecutive visits to all public primary care clinics in one large territory of Hong Kong during the study period from January 2004 to June 2007. Binary logistic regression analyses were carried out with antihypertensive drug switching as an outcome variable, while controlling for age, gender, payment status, service types, district of residence, visit types and the number of comorbidities. Among 93,286 eligible patients, 5281 (5.7%) switched their antihypertensive prescriptions to another drug class within 180 days. Patients aged > or =70 years (adjusted odds ratio (aOR) 0.88, P=0.005), male subjects (aOR 0.87, P<0.001) and follow-up visitors (aOR 0.67, P<0.001) were less likely to have their drugs switched. When compared with thaizide diuretics, all other antihypertensive drug classes were associated with a lower likelihood of drug switching (aOR 0.27-0.69, all P<0.001). Closer observations of drug utilization profiles among these patient groups are recommended, and future studies should evaluate the reasons for drug switching.

Antihypertensive drug treatment changes in the general population: the colaus study

“…This study also allowed the analysis of a considerable number of factors associated with antihypertensive drug changes. Further, several studies that assessed changes in antihypertensive drug treatment used only two [1,26,27] or three categories such as “continuers”, “switchers” and “discontinuers” [14]. In this study, we opted for a four-category classification as suggested by Mazzaglia and colleagues [7] because it reflected more accurately the behavior of a practitioner when managing a patient with hypertension.…”

Adherence to Oral Hypoglycemic Agents in 26 782 Chinese Patients: A Cohort Study

“…In our recent evaluation of adherence profiles of antihypertensive agents in Chinese, we reported that hypertensive patients were consistently more likely to be adherent among the older patients and follow-up visitors but there were conflicting results about adherence in men and women. [15][16][17][18][19][20][21][22] Nevertheless, these studies measured the adherence profiles to antihypertensive agents only, and little was known about adherence patterns to oral hypoglycemic agents (OHAs) in ethnic Chinese.…”

Switching of antihypertensive drugs at tertiary care government hospital, Hyderabad, India: A cross-sectional retrospective investigation

“…Unlike the study conducted in the Chinese population, where combination therapy (single pill combination) showed less likelihood of drug switching, our study showed that the polytherapy was significantly associated with a change in the medication. [ 14 ] However, polytherapy could be a single pill combination or multiple pill combination which was not differentiated in our study; this multiple pill combination could have led to antihypertensive medicine switchover as >1 drug/multiple pill combination used for treating HTN may prime to inefficient BP control due to less adherence. [ 21 ] In addition, it was also seen that increasing the number of pills had a negative effect on compliance and on persistence on therapy, translating into poor clinical outcomes.…”

“…[ 17 18 ] On the other hand, studies from China disclosed very less switchover (5.7% and 3.9%) of antihypertensive medication. [ 13 14 ]…”

“…Switching of therapy is defined as the absence of a refill prescription in all subsequent clinic visits combined with the prescription of another antihypertensive drug of a different class within 180 days since the date of the first prescription. [ 13 14 ]…”