A systematic review and meta-analysis of non-adherence to anti-diabetic
medication: Evidence from low‐ and middle‐income countries
Abstract
Objective: There is lack of evidence on the burden of and factors
associated with non-adherence to anti-diabetic medication among
individuals living with diabetes in low-and middle-income countries
(LMICs). Therefore, we carried out a systematic literature review and
meta-analytic synthesis to estimate non-adherence to anti-diabetic
medication reported among adults in LMICs and to explore factors
affecting non-adherence. Methods: We systematically searched MEDLINE and
Embase to identify studies investigating non-adherence to anti-diabetic
medications published between January 2000 and May 2020. Cross-sectional
studies that had been conducted among individuals with diabetes in LMICs
were eligible for the selection process. Critical appraisal of the
included studies was carried out using the Newcastle Ottawa Scale.
Meta-analysis was carried out using Stata 14.2. Random effects model was
used to compute the pooled proportion at 95% confidence interval.
Results: Forty-three studies met the inclusion criteria, of which 13
studies were used in meta-analysis. The pooled proportion of
non-adherence to anti-diabetic medications using the eight-item Morisky
Medication Adherence Scale (MMAS) was 43.4% (95% CI: 17.5–69.4;
p=0.000) and 29.1% (95% CI: 19.8–38.4; p=0.000) when using the
cut-off at 80 or 90%. The pooled proportion of non-adherence was 29.5%
(95% CI: 25.5–33.5; p=0.098) when using the four-item Morisky
Medication Adherence Scale. The factors for non-adherence based on World
Health Organization demonstrated considerable variation of non-adherence
to ant-diabetic medication in LMICs depending on the methods used to
estimate non-adherence. Conclusions: These findings demonstrate a
significantly higher proportion of medication non-adherence among
individuals with diabetes in LMIC settings when MMAS-8 item scale was
used and low when 80-90% cut-off scales were used. Various factors,
such as disease factors, therapy-related factors, healthcare system
factor, patient-centered factors, and social and economic factors
contributed to non-adherence. Therefore, comprehensive multifaceted
strategies are urgently needed to address factors associated with
anti-diabetic medication non-adherence.