Medication adherence and associated factors among glaucoma
patients attending MCM (Korean) General Hospital Eye
Department. Addis Ababa, Ethiopia
Investigator-Biruk Teke
Advisor- Dr Ayele Zewdie
December 19, 2020
Introduction
• Glaucoma is a type of eye disorder resulting from optic neuropathy
and leads to a progressive loss of retinal ganglion cell axons and
ultimately irreversible blindness if left untreated.
• It is a silent disease with progressive loss of vision without patients
exhibiting any symptoms.
• If an appropriate treatment strategy is initiated early enough, glaucoma
blindness can be prevented in most patients.
Cont’d
• Worldwide, glaucoma is affecting approximately 60 million people.
• As the global population ages, it is projected that glaucoma will affect
approximately 110 million by 2040.
• To date, 12.3% of the bilateral visual loss cases worldwide are due to
glaucoma.
• In Africa, blindness due to glaucoma accounts for 15%, and it is the
region with the highest prevalence of blindness relative to other regions
worldwide.
Cont’d
• Glaucoma inexplicably affects more Africans and Asians than whites
and it is considered as a public health problem in sub-Saharan Africa.
• In Ethiopia, glaucoma is a common cause of blindness which results
an irreversible sight loss for an estimated 62,000 Ethiopians.
• Patients’ lack of awareness of the nature of the disease and the risks of
failure to comply with treatment are the two factors hindering proper
treatment in chronic diseases such as glaucoma.
Cont’d
• Lowering intraocular pressure is the only proven method of
minimizing both the development and progression of glaucoma.
• The most common first-line therapy is medical therapy.
• Glaucoma medications are used over a long period or life-long that
require long-term adherence.
Cont’d
• Adherence to treatment is defined as “patient’s compliance with
medical recommendations offered by healthcare providers”
• It is generally considered to be the degree to which treatment goals
and pathways are met, as mutually defined by the patient and their
physician, through ongoing and consistent administration of clinical
interventions.
• Medication non-adherence is recognized as one of the most important
and costly worldwide healthcare problems in the 21st century.
cont’d
• A meta-analysis of adherence studies demonstrated a wide range of
adherence levels, varying between 5% and 80%, which was also due
to the fact that no common definition of adherence was in place.
• Institution based studies showed the overall rate of adherence for
glaucoma medication was 69.7% in Australia, 72.4% in Japan, 75% in
Malaysian, 72.6 % in South Korea, 50% in India and 46.4% in Egypt.
• In Ethiopia adherence level was 42.6% at Menelik II Referral
Hospital, 32.5% at Jimma University Specialized Hospital and 61.4%
at Gondar University Hospital Tertiary Eye Care Center
Problem statement
• Glaucoma is a chronic disease that requires regular ophthalmologic
examinations and strict patient compliance with topical medications.
• Assessing the adherence level of these topical medications is
important to make sure that the patients effectively controlled their
intraocular pressure.
• Further exploring of the factors affecting compliance in glaucoma
setting will be the first step towards improving patient compliance.
Cont’d
• A more thorough understanding of the causes of non-adherence is
necessary for the development of effective clinical interventions and to
improve therapeutic outcomes.
• The main purpose of this study is, therefore, to provide evidence to
increase the success rate of treatment and a baseline data for further
investigation.
Objectives
General objective
• To assess the level of topical glaucoma medication adherence and
associated factors contributing to non-adherence among glaucoma
patients attending MCM (Korean) General Hospital Eye department. Addis
Ababa, Ethiopia.
Specific objectives
• To determine the level of topical glaucoma medication adherence.
• To identify associated factors affecting topical glaucoma medication
adherence.
Study Design
• A hospital-based prospective cross-sectional study will be conducted
at glaucoma clinic MCM General Hospital.
• Eligible patients, who attended the clinic during the course of the
study will be interviewed and their medical records will be reviewed
prospectively.
Source and Study Population
• The source population will be all glaucoma patients who received
services at the glaucoma clinic of MCM General Hospital.
• On the other hand, the study population will be all glaucoma patients
who will receive services during the study period at the clinic.
Sample Size Determination and Sampling Technique
Objective 1: Sample size for level of medication adherence.
• The minimum sample size will be calculated using a formula
used to estimate the sample size for a single population,
• Previous study in Gondar University Hospital shows adherence
level of (61.4%) (95% confidence interval: 56.1–66.7)
n=
Z (1
α 2 2
− / ) (
𝑑2
p×q)
= (1.96)2×0.614×0.386/ (0.05)2= 364
Cont’d
• As the estimated total study population is < 10,000 (An average from
the last four years register shows 1126 patients were examined on same
period of data collection) correction formula was then used.
nF=
n
1+n/N
=
364
1+326/1126
=
275
• Sample size with 10% non-response rate will be 275+ 27.5 = 302.5 ≈
303
cont’d
• Objective 2: Sample size for associated factors calculated using Epi
Info 7 Stat calculator by double proportion formula at 95% confidence
interval and 80% Power.
Factors
High education level
Self-sponsor medication
Less frequency of medication
Exposed
(%)
Non Exposed
(%)
53.57
68.4
25
8.3
40.3
5.9
CI
95
95
95
Power
80
80
80
Ratio
1:1
1:1
1:1
Total sample
size
40
112
182
• Sample size of objective two was less than objective one so that
sample size for objective one 303 is taken as the final sample size.
cont’d
• Within the data collection period each consecutive patient who will fulfill
the inclusion criteria, will be interviewed and medical record will be reviewed
for the needed data.
• Morisky Medication Adherence Scale – 8 (MMAS – 8) will be used to
asses adherence level.
Feasibility of the study
• Technical- The study area, availability of up-to-date resources and
expert advisor support contributes to its technical feasibility.
• Financial- The research project requires 20,294 birr which can be
covered by personally or through sponsor.
• Time – This project can be finalized proactively with in the given
schedule.
Reference
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