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Role of text messages in improving eye clinic attendance among diabetic patients
*Corresponding author: Nievel Buetnaan Maigida, Department of Ophthalmology, Jos University Teaching Hospital, Plateau State, Nigeria. nwalul@yahoo.com
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Received: ,
Accepted: ,
How to cite this article: Maigida NB, Adenuga O, Mpyet C. Role of text messages in improving eye clinic attendance among diabetic patients. Global J Cataract Surg Res Ophthalmol. 2026;5:38-44. doi: 10.25259/GJCSRO_51_2025
Abstract
Objectives:
The aims of the study are to determine whether mobile phone message reminders will improve adherence to scheduled ocular examinations amongst diabetic patients attending the eye clinic in Jos University Teaching Hospital, with a view to recommending intervention to prevent blindness.
Materials and Methods:
It was a comparative hospital-based trial, with patients grouped in a 1:2 ratio with one group receiving short message service (SMS) reminders about their next appointment and the other not receiving an SMS. 164 consecutive patients were recruited. This was calculated using the attendance rate obtained from a similar study done in China and imputing it into a formula comparing two proportions. All recruited patients received a health talk about diabetes and how it affects the eye and the importance of adherence to eye clinic appointments. A semi-structured questionnaire was administered to determine their knowledge about DR. A full ophthalmic examination and dilated funduscopy were carried out on participants who attended the eye clinic.
Results:
One hundred and sixty-four participants were invited to participate in the study. There were 132 female participants and 32 males. The mean age of study participants was 53.9 ± 11.9 years. The overall eye clinic attendance rate was 55%. Only 24 (44.4%) of participants in the SMS group honoured the eye clinic invitation; 30 (55.6%) did not attend. While 66 participants (60%) in the non-SMS group attended the eye clinic appointment. This finding was not statistically significant. SMS was not effective as a reminder for diabetic patients to attend the eye clinic in this study. Barriers associated with poor clinic attendance were travel and other competing needs. Factors associated with poor eye clinic attendance were low awareness about DR (odds ratio [OR]: 9.818, 95% confidence interval [CI]: [1.953–49.351]), age <50 years (OR: 9.00, 95% CI: [2.649–30.588]) and low literacy levels (OR: 7.99, 95% CI: [2.018–31.640]). Knowledge about diabetes, DR and treatment options improved at the eye clinic visit when compared to the first general outpatient department visit following health talks.
Conclusion:
The findings of this study suggest that use of SMS messages alone is not an effective way of enhancing by adequate knowledge about diabetic retinopathy.
Keywords
Clinic attendance
Diabetes mellitus
Eye clinic
Jos University Teaching Hospital
Short message service
INTRODUCTION
Diabetes mellitus (DM) is a metabolic disorder of chronic hyperglycaemia resulting from absolute or relative insulin deficiency, resulting in dysfunction in organ systems. The most common microvascular complications of DM affecting the retinal vessels in the eye include diabetic retinopathy (DR) and macular oedema.[1] Reasons for loss of vision are diabetic maculopathy and complications of proliferative DR (PDR). Risk factors for DR include duration of diabetes, being higher amongst those diabetic >10 years, poor glycaemic control, pregnancy, hypertension and nephropathy.[2]
Ignorance about DR, poverty and cost of treatment are reasons for poor adherence to follow-up.[3] Studies have shown that short message service (SMS) reminders for follow-up and patient education about the ocular complications of diabetes can help to increase adherence to follow-up.[4,5] In a bid to improve adherence to eye care, Chen et al. conducted a randomised control study in China and reported that there was improved compliance with eye care screening when diabetic patients received text message reminders before their appointments.[4]
This study is aimed at determining if mobile SMS reminders will improve adherence to eye clinic appointments amongst diabetics in this part of the world.
Literature review
Global burden of DM
The number of people aged 20–79 years with DM globally is estimated to be 9.3% (463 million people), rising to 10.2% (578 million) by 2030.[6] The prevalence is higher in urban areas (10.8%) than in rural areas (7.2%). One in two people living with DM does not know that they have DM.
Burden of DM in Nigeria
There has been no nationwide health survey in Nigeria since 1992, when a DM prevalence of 2.2% was reported.[1]However, a systematic review carried out by Uloko et al. in 2018 reported an overall pooled prevalence of DM to be 5.77% using prevalence from the 6 geopolitical zones of Nigeria.[1]
This increase in the prevalence of DM comes along with an increase in complications. At Jos University Teaching Hospital (JUTH), diabetic foot ulcers were reported to make up 11.4% of all DM admission at 2006.[7]
Burden of DR in Nigeria
DR is the most common microvascular complication of DM. Globally, it accounts for 5% of blindness, affecting 2 million people.[8] Diabetic macular oedema is the most common cause of blindness amongst patients with DR.[9] DR develops with the increasing duration of diabetes.[10,11]
The Nigerian national blindness survey of 2005–2007 documented that 20.5% of diabetics had DR with >10% of them having sight-threatening DR.[8]
Ewuga et al. documented a prevalence of DR of 18.5% in a study conducted in Jos, North Central Nigeria.[12] Major risk factors documented were the duration of DM and poor glycaemic control. Kizor-Akaraiwe et al. documented the prevalence of DR to be 32.1% in a screening centre in Enugu, southeastern Nigeria.[13]
Role of SMS reminders in ophthalmology
Chen et al.,[4] in a study done in rural China amongst diabetics, discovered that eye clinic attendance was higher amongst the intervention group when compared with the control, 42.9% as against 14.0%. The primary outcome was attendance within 1 week of the scheduled visit.
This study is aimed at determining if mobile SMS reminders will improve adherence to eye clinic appointments. Information from this study could also be useful in modifying the DR screening in Jos University Teaching Hospital (JUTH) to ensure better compliance with eye care amongst DM patients, which could eventually reduce the morbidity associated with DR.
MATERIALS AND METHODS
This was a hospital-based comparative study carried out at a teaching hospital in North central Nigeria. The study was carried out over 7 months after receiving ethical approval from the JUTH ethical committee.
The minimum sample size required to detect a difference in clinic attendance between those who receive SMS reminders and those who do not was estimated using the sample size formula for two sample comparison of proportions. Randomisation was done at a ratio of 1:2. One hundred and sixty-four (164) diabetic patients attending the general outpatient department (GOPD) clinic in JUTH were randomised into two groups: an intervention group which received SMS intervention and clinic attendance adherence education and a control group which only received clinic attendance adherence education.
Sample size was calculated as follows:
Where N = Minimum sample size for each group,
Z1−α/2 = Standard normal deviate corresponding to the probability of type 1 error (α) at 5% = 1.96,
Z1−β = The standard normal deviate at 90% statistical power, corresponding to the probability of making a type 2 error (α) = 1.28,
P1 is the proportion in population 1 from a similar study conducted in China that did not receive SMS reminder = 0.14 (4),
P2 is the proportion in population 2, same as above, amongst patients receiving SMS reminder in the same study as above = 0.429,
(P1–P2) = Difference in proportion between P2 and P1.
N = 48
To compensate for non-response, using an expected response rate of 90% and a non-response rate of 10%,
The adjusted minimum sample size will be:
Final sample size = Effective sample size/1−Non response rate
N (adjusted) = 48/1−0.10
N = 48/0.9
N = 55
Since a randomisation ratio of 1:2 was used, the intervention group has 55 participants and the control group has 2 × 55 = 110.
The total number of participants was 164.
A semistructured, interviewer-based questionnaire was designed to obtain participants’ demographics, general knowledge about DR and documentation of ocular examination findings. A pilot study was carried out to pre-test and validate the questionnaire 1 month before the study was carried out. Informed consent was obtained from all participants.
For the purpose of the study, for every one participant that received SMS, there were two controls who did not receive SMS. The group that received SMS is the intervention group and the group that did not receive SMS is the control group. Consecutive newly diagnosed DM patients recruited at the GOPD filled a questionnaire administered by the research assistant [Appendix 1]. All recruited patients had a health talk about DM and the eye which was given by the principal researcher. The talk centred around the risk factors for DR, how DM results in blindness and the need for keeping scheduled appointments [Appendix 2]. All patients recruited at the GOPD were given a 1-week appointment at the eye clinic from the day they were recruited. Screening for DR was done at the second visit to the eye clinic. Subsequent appointment was based on the findings found at the eye clinic appointment in accordance with the early treatment diabetic retinopathy study guideline. In addition to being informed of their attendance date at the initial visit, those in the intervention group received text message reminders [Appendix 3] at 1 week and 3 days before their scheduled appointments.
The differences between the study groups in the observed proportion of subjects presenting within 1 week of their scheduled follow-up date were calculated by performing Chi-square test. Multivariate logistic regression was used to analyse the factors associated with non-clinic attendance between both groups. The level of all statistical significance was set at 95% confidence interval (CI). All statistical analysis was performed using the statistical package for the social sciences (Version 21; IBM Corp, New York, NY, USA).
Inclusion criteria
Consenting adults aged 18 years and above who were newly diagnosed with DM
Consenting participants who have personal mobile phones or have access to caregivers, relations or neighbours with mobile phones and can read or have text messages read to them.
Exclusion criteria
Patients who did not consent to the study
Diabetic patients <18 years
Patients who had no mobile phones or access to mobile phone from caregivers
Patients who have had a previous eye examination.
RESULTS
Sociodemographic of study participants
The mean age of the 164 participants was 53.9 ± 11.9 years. The mean age in the SMS group was 53.44 years while the mean age in the non-SMS group was 54.44 years. There were more participants in the 50–59 age group, 56 (34.1%). There were more female participants in the study, 132 (80.5%), as seen in Table 1, with female dominance in both the intervention and the control groups. This finding was not statistically significant (χ2 = 0.376; p = 0.536). Sixteen (9.8%) participants were not literate with 10 out of the 16 in the intervention group, and this difference in literacy levels between those who received SMS and those who did not receive SMS was also not statistically significant (χ2 = 10.073, p = 0.073). Fifty per cent of participants were into business (82) as an occupation, as seen in Table 1.
| Variable | Group | Total | Chi-Square | p-Value | ||||
|---|---|---|---|---|---|---|---|---|
| SMS | No SMS | |||||||
| n | Percentage | n | Percentage | n | Percentage | |||
| Gender | ||||||||
| Male | 12 | 22.2 | 20 | 18.2 | 32 | 19.5 | 0.376 | 0.539 |
| Female | 42 | 77.8 | 90 | 81.8 | 132 | 80.5 | ||
| Total | 54 | 100.0 | 110 | 100.0 | 164 | 100.0 | ||
| Age | ||||||||
| 20 – 29 | 2 | 3.7 | 0 | 0.0 | 2 | 1.2 | 10.373 | 0.065 |
| 30 – 39 | 0 | 0.0 | 10 | 9.1 | 10 | 6.1 | ||
| 40 – 49 | 16 | 29.6 | 26 | 23.6 | 42 | 25.6 | ||
| 50 – 59 | 20 | 37.0 | 36 | 32.7 | 56 | 34.1 | ||
| 60 – 69 | 10 | 18.5 | 20 | 18.2 | 30 | 18.3 | ||
| >70 | 6 | 11.1 | 18 | 16.4 | 24 | 14.6 | ||
| Total | 54 | 100.0 | 110 | 00.0 | 164 | 100.0 | ||
| Marital status | ||||||||
| Married | 42 | 77.8 | 80 | 72.7 | 122 | 74.4 | 1.261 | 0.532 |
| Divorced | 0 | 0.0 | 2 | 1.8 | 2 | 1.2 | ||
| Widowed | 12 | 22.2 | 28 | 25.5 | 40 | 24.4 | ||
| Total | 54 | 100.0 | 110 | 100.0 | 164 | 100.0 | ||
| Education | ||||||||
| None | 10 | 18.5 | 6 | 5.5 | 16 | 9.8 | 10.073 | 0.073 |
| Primary | 12 | 22.2 | 18 | 16.4 | 30 | 18.3 | ||
| Secondary | 8 | 14.8 | 20 18.2 | 18.2 | 28 | 17.1 | ||
| Tertiary | 12 | 22.2 | 26 | 23.6 | 38 | 23.2 | ||
| Arabic | 12 | 22.2 | 38 | 34.5 | 50 | |||
| Adult education | 0 | 0.0 | 2 | 1.8 | 2 | 1.2 | ||
| Total | 54 | 100.0 | 110 | 100.0 | 164 | 100.0 | ||
| Income (N) | ||||||||
| <18,000 | 32 | 59.3 | 62 | 56.4 | 94 | 57.3 | 7.397 | 0.116 |
| 18,000 - < 50,000 | 10 | 18.5 | 28 | 28.5 | 38 | 23.2 | ||
| 50,000<100,000 | 10 | 18.5 | 8 | 7.3 | 18 | 11.0 | ||
| 100,000<300,000 | 2 | 3.7 | 10 | 9.1 | 12 | 7.3 | ||
| >300,000 | 0 | 0.0 | 2 | 1.8 | 2 | 1.2 | ||
| Total | 54 | 100.0 | 110 | 100.0 | 164 | 100.0 | ||
| Occupation | ||||||||
| Civil servant | 8 | 14.8 | 22 | 20.0 | 30 | 18.3 | ||
| Business | 28 | 51.9 | 54 | 49.1 | 82 | 50 | ||
| Farmer | 2 | 3.7 | 10 | 9.1 | 12 | 7.3 | ||
| Unemployed | 16 | 29.6 | 24 | 21.8 | 40 | 24.4 | ||
| Total | 54 | 100.0 | 110 | 100.0 | 164 | 100.0 | ||
SMS: Short message service, p< 0.05 is statistically significant
Comparison of eye clinic attendance between intervention and control groups
More participants in the control group attended the eye clinic, 66 (60.0%), despite not getting the SMS message, compared to those in the intervention group, 24 (44.4%) who received SMS messages, as seen in Table 2. This difference in attendance between the SMS group and the no SMS group was, however, not statistically significant (χ2 = 3.539, p = 0.06).
| Attendance | Group | Total | Chi-square | p-value | ||||
|---|---|---|---|---|---|---|---|---|
| SMS | No SMS | |||||||
| n | Percentage | n | Percentage | n | Percentage | |||
| Yes | 24 | 44.4 | 66 | 60.0 | 90 | 54.9 | 3.539 | 0.06 |
| No | 30 | 55.6 | 44 | 40.0 | 74 | 45.1 | ||
| Total | 54 | 100.0 | 110 | 100.0 | 164 | 100.0 | ||
SMS: Short message service, p<0.05 is considered statistically significant.
DISCUSSION
The mean age of participants in this study was 53.9 ± 11 years. This is an indication that the population of the study participants are in the middle-aged category. Majority of the participants in this study were literate with only 9.8% having no form of education. 56% of participants had secondary and tertiary education. The incidence of type 2 DM is known to increase with increasing age. Majority of participants in this study were females. The reason could be that women have better health-seeking behaviour when compared to men, as supported by a study in India.[14]
Eye clinic attendance rate amongst participants
Ninety participants (55%) out of 164 recruited participants attended the eye clinic appointment, while 74 (45%) missed the eye clinic appointment as seen in Figure 1. 60% (66 participants) of participants in the control group (no SMS) attended the eye clinic appointment as against 44.4% (24 participants) in the intervention group (SMS group) that attended the eye clinic appointment as seen in Figure 2.
The attendance rate in this study is close to that of a similar study in China where the attendance rate was 56%.[4] In the Chinese study, the attendance rate was higher amongst the SMS group than the non-SMS group. This could be because the SMS was sent in one language in the China study and the SMS contained information about the asymptomatic nature of DR and the need for regular eye examinations. The content of SMS sent in this current study was only reminder about the scheduled date of the eye clinic appointment, while the health talk about DR and the need for examinations were given at the GOPD during the recruitment to all participants. Therefore, multifaceted interventions such as combining educational and reminder interventions are likely to be more effective than SMS reminders alone, as seen in this study.
A study in North Central Nigeria amongst first-degree relatives of glaucoma patients also documented that SMS was not effective, despite using phone calls at first to recruit the participants where those who received SMS missed their appointment (55.6%) were more than those who did not receive SMS and missed the appointment (40%).[15] A similar study in Scotland amongst patients attending primary health care clinic also documented that SMS were not effective in reducing missed appointments.[16]
Barriers to eye clinic attendance
Barriers to the eye clinic attendance between the two groups were similar with travel as the most common reason given. Other reasons given were distance to the hospital, which was seen most in the non-SMS group. This could be explained by the fact that the hospital in this study is on the outskirts of town. Most times, patients must wait for the buses to come to the hospital to fill up before departing for the hospital. Lack of transport fare was another reason which is not surprising, as majority (57%) of the participants in the study were in the low-income group. These reasons are like that found in a study by Salihu et al.[15] in a similar setting to the current study which showed distance as the major reason given by participants. The study by Salihu, however, documented fear of diagnosis as a barrier which was not documented in this study, possibly because patients already knew their diagnosis.[15] Multiple logistic regression in this study showed that participants with low awareness of DR were 11 times more likely to miss the eye clinic appointment than those with high DR awareness (odds ratio [OR]: 11.4, 95% CI [2.224–58.704]). Other barriers noted from the logistic regression model in this study were age <50, low literacy level, income <N50,000/month and travel time of more than 30 min.
Comparison of DR knowledge amongst study participants at baseline and at the end of the study
Awareness about the effect of DM on the eye was high, as 97.8% of participants responded that they knew that DM affects the eye. This is in keeping with other African studies by Lawan and Tajunisah.[11,17] This high level of knowledge can be explained by the fact that the study was done at a tertiary institution where health talks are usually given to patients in the clinics. Despite knowing about the fact that DM affects the eyes, most participants (55%) did not know about DR. This finding is similar to other studies in Nigeria by Ewuga et al.[12] and Bodunde et al.[18] This is quite worrisome as DR is the major cause of irreversible blindness in DM patients. This may be because patients are given insufficient information or do not really listen to the health talks; the former is more likely, considering the increase in the knowledge about DR recorded at the second visit. Out of the 40 participants who had heard about DR, only 28 really knew that it affects the retinal vessels. This is in keeping with a study by Ewuga et al.[12] in Nigeria and Cheruiyot in Kenya.[19] This shows that a good understanding of DR is lacking in participants who said that they knew what DR was. The knowledge about DR amongst participants increased by the second visit from 28 to 50 participants. This shows that there was an improvement in the knowledge after the health talk was given.
Ocular examination findings amongst participants
DR was graded according to the International clinical diabetic retinopathy severity scale (ICDRDSS) classification. The majority of participants did not have any DR. This is in keeping with studies in Nigeria, Malaysia, India, Egypt and Ghana.[18-22] Two per cent of the participants had PDR, with 3 participants out of 4 belonging to the control (no SMS group) and it has been observed that more than 50% can become blind if not treated for PDR.[4] This buttresses the need to increase awareness about the need for eye clinic attendance and DR screening amongst DM patients. These patients were fast tracked to see the vitreoretinal surgeon while those with tractional retinal detachment were referred to the National Eye Centre, Kaduna. Diabetic macular oedema was seen in 24 eyes of participants; hence, these are eyes that would have been missed and would have further deteriorated in vision. These patients were also fast tracked for vitreoretinal review at the hospital.
CONCLUSION
Findings from this study suggest that sending SMS reminders alone is not an effective way of enhancing eye clinic screening attendance amongst DM patients. However, attendance can be enhanced by adequate knowledge about DR. Patients attending the GOPD of this hospital had poor knowledge about the treatment options for DR. Clinic attendance can be enhanced if transport cost and distance to screening sites are reduced by the government as part of social welfare responsibility.
Ethical approval:
The research/study was approved by the Institutional Review Board at Jos University Teaching Hospital, number JUTH/DCS/IRWC/127/XXX1/12341, dated 23 November 2020.
Declaration of patient consent:
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given consent for clinical information to be reported in the journal. The patient understand that the patient’s names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Conflicts of interest:
There are no conflicts of interest.
Use of artificial intelligence (AI)-assisted technology for manuscript preparation:
The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.
Financial support and sponsorship: Nil.
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