Clinical and economic outcomes in medication-adherent and -nonadherent patients with type 2 diabetes mellitus in the Republic of Korea.
BACKGROUND
The prevalence and social burden of type 2 diabetes mellitus (T2DM) is increasing. Medication adherence is necessary for positive outcomes in patients with T2DM.


OBJECTIVE
This study evaluated the association between medication adherence and clinical/economic outcomes in patients with T2DM in the Republic of Korea over a 3-year period.


METHODS
This study used data from the Korean National Diabetes Program at 5 hospitals. Medication possession ratios of ≥90% and <90% were used to define adherent and nonadherent groups, respectively. The degree of glycemic control, changes in blood pressure and lipid profiles, and health care costs were compared.


RESULTS
Of the 608 patients, 472 were medication adherent and 136 were nonadherent. The adherent patients displayed improved fasting blood glucose and hemoglobin A1c during the study. Diastolic blood pressure and total cholesterol were lower at 36 months, and lower low-density lipoprotein cholesterol was noted at baseline and 24 months. The total health care costs were $1861, $2060, and $1924, respectively, versus $1617, $1751, and $1602 during the 3-year study period for the adherent group versus the nonadherent group, respectively (P = 0.316, 0.627, and 0.172, respectively), whereas the outpatient drug costs were $1143, $1176, and $1162 in the adherent group versus $925, $778, and $914 in the nonadherent group (P = 0.002, P < 0.001, and P = 0.001).


CONCLUSIONS
The adherent patients displayed better glycemic control and lipid profiles. Medication-related expenses were higher in the adherent group, but overall health care costs, including hospitalization costs, were similar between the 2 groups.
Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, Republic of Korea.
So-Yeon
SY
An
Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, Republic of Korea.
Hae Jin
HJ
Kim
Department of Preventive Medicine and Public Health, Ajou University School of Medicine, Suwon, Republic of Korea.
Ki Hong
KH
Chun
Department of Internal Medicine, Kwandong University College of Medicine, Gangneung, Republic of Korea.
Tae Ho
TH
Kim
Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, Republic of Korea.
Ja Young
JY
Jeon
Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, Republic of Korea.
Dae Jung
DJ
Kim
Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, Republic of Korea.
Seung Jin
SJ
Han
Department of Internal Medicine, Kyung Hee University College of Medicine, Seoul, Republic of Korea.
Young Seol
YS
Kim
Department of Internal Medicine, Kyung Hee University College of Medicine, Seoul, Republic of Korea.
Jeong Taek
JT
Woo
Department of Internal Medicine, Kyung Hee University College of Medicine, Seoul, Republic of Korea.
Kyu Jeung
KJ
Ahn
Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Republic of Korea.
Yongsoo
Y
Park
Department of Internal Medicine, Inha University College of Medicine, Incheon, Republic of Korea.
Moonsuk
M
Nam
Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
Sei Hyun
SH
Baik
Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, Republic of Korea. Electronic address: lkw65@ajou.ac.kr.
Kwan-Woo
KW
Lee
D000368:Aged; D001786:Blood Glucose / Q000032:analysis; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000453:epidemiology / Q000503:physiopathology*; D016527:Drug Costs / Q000706:statistics & numerical data*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D017048:Health Care Costs / Q000706:statistics & numerical data; D017721:Hospital Costs / Q000706:statistics & numerical data; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008297:Male; D055118:Medication Adherence / Q000523:psychology; D008875:Middle Aged; D011446:Prospective Studies; D056910:Republic of Korea
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents
adherence to medication; clinical and economic outcomes; type 2 diabetes mellitus