Article Text
Abstract
Background/aims To assess the reasons and factors for discontinuation of follow-up among patients with glaucoma at a tertiary referral teaching hospital in Seoul, Korea.
Methods We identified all adult patients with glaucoma (≥18 years), who had visited the glaucoma clinic of Seoul National University Hospital between April 2012 and March 2014 and had missed an appointment by at least 12 months. These patients were traced via cellular phone, and their true status and reasons for discontinuation of follow-up were documented.
Results A total of 6848 patients with glaucoma (3512 men and 3336 women) were considered. Among them, 247 (3.61%) had missed a scheduled appointment by 12 months or more. Among 230 (93.1%) who were successfully traced, 4 (1.7%) had died and 96 (41.7%) had self-transferred to another glaucoma clinic. Of the 130 patients left, 123 (94.6%) had treatment and follow-up interruptions, and 7 (5.4%) had been treated with alternative medicine. The two main reasons cited for treatment and follow-up interruptions were lack of understanding regarding the necessity of follow-up (46.3%) and unawareness of appointment schedule (30.9%). In stepwise linear regression analysis, older age (p=0.001. β=0.13), male gender (p=0.013, β=0.08) and lower baseline intraocular pressure (p=0.005, β=0.11) were independently associated with follow-up loss involving treatment interruptions.
Conclusions This study's results emphasise the need for ongoing educational support and improved appointment notification, especially for the elderly, men and patients with low baseline intraocular pressure.
- Glaucoma
- Public health
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Introduction
Glaucoma is the leading worldwide cause of irreversible visual impairment, affecting more than 70 million people.1 As this condition requires life-long management to delay disease progression,2 early detection and regular follow-up are essential to preventing severe visual field (VF) loss later in life.
Glaucoma management has evolved rapidly, with several models and care pathways. Nonetheless, a certain proportion of patients with glaucoma misses follow-up appointments or is completely lost to follow-up. In the UK, an analysis of data from a customised reporting and learning system revealed that—among 135 patients with glaucoma who had reported delayed, postponed or cancelled appointments—vision had deteriorated in 44, of whom 13 had lost vision completely.3 These data show that failure to follow-up on patients with glaucoma can cause significant harm.
Several studies on compliance4–7 and persistency8–12 among patients with glaucoma have been reported. However, there is a paucity of presentations and published papers focusing on the importance of regular surveillance and the perils of non-compliance with follow-up regimens. Further, most clinical studies involve patients who have adhered to their appointment schedules. More serious vision deterioration or glaucoma progression can occur in precisely those patients who are hidden or lost. Thus prompted, the present study traced patients with glaucoma who had been lost to follow-up at a tertiary referral teaching hospital to assess their status and to determine their reasons for discontinuation of follow-up. Further, to identify the risk factors for discontinuation of follow-up, sociodemographic and clinical data were collected from patients who had been lost to follow-up and compared with those of patients who had continued with follow-up.
Methods
This study followed the tenets of the Declaration of Helsinki and was approved by the Institutional Review Board of Seoul National University Hospital.
Study subjects
The electronic medical records of patients with glaucoma who had visited the glaucoma clinic of Seoul National University Hospital between April 2012 and March 2014 were compiled by the author KHP and retrospectively reviewed.
All of the study subjects had undergone a complete ophthalmic examination, including visual acuity assessment, refraction, slit-lamp biomicroscopy, gonioscopy, Goldmann applanation tonometry and dilated stereoscopic examination of the optic disc. Additionally, digital colour stereo disc photography (SDP), red-free retinal nerve fibre layer (RNFL) photography and a central 30-2 threshold test of the Humphrey Visual Field (HVF; Humphrey Instruments, Dublin, California, USA) were performed. Subsequently, patients with mild-to-moderate glaucoma were prescribed 5–6 months follow-up interval (ie, approximately two visits/year), while patients with severe glaucoma were prescribed 3–4 months interval (ie, approximately four visits/year).
The inclusion criteria were (1) age older than 18 years, (2) an optic disc characteristic of glaucoma (ie, showing localised or diffuse neuroretinal rim thinning) on SDP images and/or (3) RNFL defect visible on red-free fundus images and (4) reliable glaucomatous visual field defects on HVF results. Glaucomatous visual-field defects were defined as (1) a cluster of three points with probabilities <5% in at least one hemifield on a pattern deviation map, including at least one point with a probability <1% or a cluster of two points with a probability <1%, (2) glaucomatous hemifield test results outside the normal limits or (3) a pattern SD beyond 95% of the normal limits, as confirmed in at least two reliable examinations (<15% false-positive/negative rate; <15% fixation losses). The control group comprised patients who had continued with follow-up at the glaucoma clinic of Seoul National University Hospital between April 2012 and March 2014; it was randomly selected, at a rate of 2/100, to allow for comparison with the patients lost to follow-up in terms of sociodemographic and clinical data.
Questionnaire for patients lost to follow-up
Before formal commencement of the study, a pilot study was conducted with 21 patients to validate the questionnaire-testing feasibility as well as the acceptability of the protocol. Based on the pilot study results, we estimated that more than 200 patients would be adequate for identification of predictors of poor follow-up with an OR of 2 or greater, with 80% power. The study questionnaire is shown in figure 1. The main questions were: (1) What is your current status as of the last follow-up? (2) Why did you not revisit the hospital after the last follow-up? (3) How satisfied were you with the explanation about your disease from the clinician? (4) How satisfied were you with the explanation about your follow-up schedule from the clinician?
Tracking of patients lost to follow-up
Patients who had missed a scheduled appointment by 12 months or more were defined as lost to follow-up; a list of such patients was generated by the electronic medical record system and verified by two investigators (JWJ and YKK) to rule out data errors. Confirmed patients were traced by cellular phone. The detailed method for tracking the patients lost to follow-up is as shown in figure 1. First, we obtained informed consent from the participants. Then, the standardised cellular phone interview questionnaire protocol, in multiple choice answer format, was administered orally in Korean to all of the subjects. The tracking outcomes were recorded on a spreadsheet as (1) ‘self-transfer’ (if the patient had arranged a transfer independently, with uninterrupted therapy); (2) ‘treatment and follow-up interruption’; (3) ‘deceased’; (4) ‘refused to be interviewed’ or (5) ‘failure to connect’ (if the patient did not answer our call after a total of six attempts; 2×3 different days). Further, the tracers collected information on the reasons for discontinuation of follow-up using multiple-alternative questions: (1) ‘felt regular follow-up unnecessary’; (2) ‘unawareness of scheduled appointment’; (3) ‘weakness or illness’; (4) ‘lack of money’; (5) ‘side effects of glaucoma medication’; (5) ‘dissatisfaction with clinic or hospital’ or (6) ‘other reasons’.
Data analysis
Statistical analyses were performed using SPSS software V.19.0.0 (SPSS, Chicago, Illinois, USA). Descriptive statistics were used to explore the baseline characteristics of the study subjects. Univariate and stepwise multivariate linear regression analyses were used to investigate factors associated with loss to follow-up. A value of p<0.05 was considered to denote significance.
Results
Between April 2012 and March 2014, a total of 6848 patients with glaucoma (3512 (51.3%) men and 3336 (48.7%) women) visited KHP's glaucoma clinic at Seoul National University Hospital. Of these, 247 (3.61%) had missed a scheduled appointment for 12 months or more (figure 2).
Tracking results and statuses of patients lost to follow-up
Of the 247 patients lost to follow-up, 17 (6.9%) could not be traced for one of the following reasons: change to phone number outside the clinic's catchment area (n=10) or refusal to be interviewed (n=7). Of the 230 patients who were successfully traced, 4 (1.7%) had died and 96 (41.7%) had self-transferred to another glaucoma clinic. Of the 130 patients left, 123 (94.6%) had treatment and follow-up interruptions and 7 (5.4%) had been treated with alternative medicine (figure 2).
Comparison of demographic and clinical data between patients lost to follow-up and patients who continued with follow-up
The control group (n=135) comprised patients randomly selected, at a rate of 2/100, from the pool of patients who had continued with follow-up between April 2012 and March 2014 (n=6725). The patients who had treatment and follow-up interruptions did not differ significantly from the control group in the following baseline sociodemographic and clinical characteristics: region (p=0.193), diabetes mellitus (p=0.890), systemic hypertension (p=0.703), spherical equivalent (p=0.584), central corneal thickness (p=0.441), axial length (p=0.178), HVF pattern SD (p=0.252) and follow-up interval (p=0.488). In addition, there were no significant differences in the types of glaucoma (p=0.070). However, the patients who had treatment and follow-up interruptions showed significantly older age (p=0.003), a higher proportion of the male gender (p=0.020), lower baseline intraocular pressure (IOP; p<0.001) and worse HVF mean deviation (MD) (p=0.005) (table 1).
Reasons for treatment and follow-up interruptions
All of the patients who had treatment and follow-up interruptions (n=123) were also asked about their reasons for discontinuation of follow-up. The reasons cited were: lack of understanding regarding the necessity of follow-up (n=57; 46.3%), unawareness of appointment schedule (n=38; 30.9%), weakness/illness (n=15; 12.2%), lack of money (n=7; 5.7%), side effects of glaucoma medication (n=3; 2.4%) and dissatisfaction with the clinic or hospital (n=3; 2.4%) (table 2).
Level of patient satisfaction with explanation from medical staff
All of the living patients who had follow-up interruptions (n=227) were also asked about their satisfaction with the medical staff's explanation about their disease status and next appointment. The levels of satisfaction indicated were: very satisfied (n=2; 0.9%), satisfied (n=9; 4.0%), dissatisfied (n=87; 38.3%) and very dissatisfied (n=129; 56.8%).
Factors associated with follow-up loss involving treatment interruptions
The univariate analysis showed that loss to follow-up involving treatment interruptions was significantly associated with older age (p<0.001, β=0.47), male gender (p=0.002, β=4.25) and lower baseline IOP (p=0.001, β=3.13). The stepwise and multivariate binary logistic regression analysis included all of the parameters for which the p value was 0.05 or less in the univariate analysis. The results revealed that the incidence of follow-up loss involving treatment interruptions remained significantly associated with older age (p=0.001, standardised β=0.13), male gender (p=0.013, standardised β=0.08) and lower baseline IOP (p=0.005, standardised β=0.11) (table 3).
Discussion
Patients with glaucoma require lifelong treatment and follow-up care for preservation of vision.13 The importance of adherence to follow-up regimens is highlighted in several studies, all of which found an association between worsening glaucoma severity and poor follow-up.14 ,15 In the present study, performed at a tertiary referral teaching hospital, we evaluated the proportion of patients with glaucoma who were lost to follow-up, and found that the incidence was 3.61% across 2 years. Of the 230 patients who were successfully traced, more than half of them (130 patients; 56.5%) had not had any contact with any other ophthalmologists. The two main reasons cited for treatment and follow-up discontinuation were lack of understanding regarding the necessity of follow-up and unawareness of the appointment schedule.
The most notable finding of this study was this: the main reasons for loss to follow-up were those that could have been avoided by increased physician–patient communication. For instance, of the 123 patients who had treatment and follow-up interruptions, almost half (46.3%) indicated that they had not understood the purpose of the follow-up. This finding is related to the general lack of communication between physicians and patients. Also, it was confirmed, based on the results of the patients' satisfaction questionnaire, that almost all patients (about 95.2%) lost to follow-up felt that there had been a lack of explanation about their disease status and next appointment. The second most common reason (30.9%) for loss to follow-up was unawareness of the appointment schedule. Usually, a hospital provides all patients who require follow-up treatment with a printed appointment schedule, additionally sending them an automatic mobile alarm; these aids evidently had not been sufficient for the patients above-noted. In this regard, we need to establish a strategy for identifying patients with glaucoma at high risk of missing their next appointment, and we also need to pay more attention to those individuals specifically. Furthermore, we need to educate them well about the dangers of insufficient follow-up.
The incidence of loss to follow-up was significantly associated with lower baseline IOP in this study. Factors contributing to poor follow-up adherence among patients with glaucoma with low baseline IOP might include lack of visual or systemic symptoms. The higher incidence of loss to follow-up among patients with lower baseline IOP was consistent with the result of a previous study, which is that patients with an early stage of glaucoma or those who had not been prescribed an ocular hypotensive therapy had a higher risk for loss to follow-up.16 These results contrast with those of Ung et al,14 who showed that patients with poor follow-up were significantly more likely to have severe glaucomatous disease. There are several reasons for these disparate results, one of which is differing demographic characteristics between study subjects. The study of Ung et al enrolled a metropolitan county hospital population in the USA, nearly half (44.7%) of which had severe glaucoma. The current study, however, enrolled subjects who had visited a tertiary referral teaching hospital in Korea and who had early-to-moderate glaucoma (mean value of VF MD: −6.71±2.94 dB).
Other factors contributing to poor follow-up adherence in the patients with glaucoma evaluated in this study were older age and male gender. A previous study inferred, from its finding of a lesser sensitivity to disease status among older patients, a higher incidence of loss to follow-up among such patients.17 On the other hand, the association between higher incidence of loss to follow-up and male gender can be explained in two ways. First, it could be the result of the tendency for women to consult a doctor earlier and more often than men, both in the case of noticing symptoms of illness and for healthcare needs related to childbearing.18 This might give rise, in turn, to a stronger tendency among women to keep their clinic appointments and to maintain subsequent follow-up schedules over time. Second, and especially in Confucian culture, male patients might be more inclined to bear physical maladies than to actively seek treatment.
The important issue remaining to be discussed is the possible association between high medical cost and increased risk for loss to follow-up. However, Korea has a national health insurance system that is administered under the National Health Insurance Program.19 In 2016, the total number of covered people was over 47 million, more than 96.3% of the total population. When an insured individual visits the outpatient clinic of a tertiary care hospital, he or she pays a per-visit consultation fee and 50% of the treatment and examination cost. The average cost incurred in the initial visit for a complete glaucoma examination at a tertiary referral teaching hospital in Korea is approximately US$260. Patients subsequently have follow-up visits at 4–6-month intervals, which cost about US$150 per visit, including the ophthalmic examination and medications. Thus, on average, per year, a patient spends about US$300–450. As medical costs are much cheaper in Korea relative to many Western countries, the cost issue seemed not to be an important reason for discontinuing treatment and follow-up at the glaucoma clinic in this study (only 7 of 123 patients cited the reason for loss to follow-up as ‘lack of money’; table 2).
Another point that needs to be emphasised was that, in this study, the proportion of patients who were lost to follow-up was only 3.61% across 2 years. A prior study in rural South India showed that 86.5% of newly diagnosed patients with glaucoma lacked appropriate clinical follow-up at 1 year.20 In a study on a metropolitan county hospital in the USA, 59.7% of established patients with glaucoma were classified as ‘poor follow-up’.14 There are several possible reasons for these disparate results among studies. First, the study subjects' demographic characteristics including ethics, education levels, socioeconomic status and disease severity were quite different. Second, the respective criteria for evaluation of adherence to the recommended follow-up schedules were dissimilar. Finally, the reputation of the relevant hospital and/or physician could also have contributed to the very low rate of non-compliance recorded in the current study.
In the course of this study, we learned several lessons that will inform improvements in the follow-up of patients with glaucoma. First, optimal treatment requires effective ophthalmologist–patient communication that is sustained for years.21 For example, practitioners should devote effort to educating patients with glaucoma on the benefits of medication adherence and on the specific risks incurred when follow-up is insufficient. The glaucoma clinic of Seoul National University Hospital has provided patients with explanations about disease both from physicians and physician assistants. However, the amount of education content was insufficient, and thus it was necessary to give the patients a supplementary explanation. The second lesson learned from this study is, methods tailored to the task and process of informing elderly patients of appointments need to be developed. Third, clinicians need to be aware of the treatment side effects that can negatively affect patient compliance and persistence. Fourth and finally, clinicians need to be aware of the fact that for some patients, treatment cost is an issue as well. We added the following working suggestions (formulated in the light of the findings of this study) that would be helpful for clinicians and/or hospitals seeking to lower the risk of follow-up loss.
Four working suggestions to lower the risk of follow-up loss
Informing patients' family (as well as patients themselves) of future appointments. Although an improved alert system is helping patients to remember their appointments better, there still might be unavoidable mistakes, even by patients who are willing to keep their appointments.
Sharing information on follow-up loss among hospitals or institutes. Patients lost to follow-up at certain clinics or departments might be more likely to be lost to follow-up also at other clinics. If we have information on given patients' history of missing, or tendency to miss, follow-up appointments, preventive action could be taken beforehand.
Providing patients with additional information from a physician assistant following the clinician's consultation. In this way, patients can satisfy their curiosity about their disease status and treatment plan (including follow-up schedule).
Paying a deposit for the next appointment. If one prepays some part of the expense of a future visit or examination, one might pay more attention to their follow-up schedule.
Study limitations
When interpreting the results of this study, several points have to be kept in mind. First, patient records were compiled and evaluated by a single physician (KHP) at a single tertiary referral teaching hospital in Seoul, South Korea, in order to discriminate patients lost to follow-up from all patients with glaucoma for the given time period. The results therefore might have been different if the study had been carried out using a different group of patients. Indeed, they might not be relevant in all cases, because each patient's behaviour can vary according to physician, hospital, ethnicity and country. Even so, the data collected were a large-scale corpus spanning 3 years, the tracking of patients lost to follow-up was comprehensive and the conclusions drawn will in any case help physicians both to understand the reasons for loss to follow-up and to predict which patients will be lost.
The second point to consider when interpreting the present results is the 2/100 random sampling that was conducted when the detailed demographic and clinical data of the patients who continued with follow-up were assessed: erroneous results remain a possibility, notwithstanding the absence of any significant differences between the two patient groups in age, gender or region. Further investigation entailing comparison of patients lost to follow-up with all same-cohort patients with glaucoma who had continued with follow-up is required. Additionally, cellular phone based tracking studies have an intrinsic limitation regarding the reliability of patients' answers. Even though we confirmed the identification of the patients who picked up the phone, and collected information about their status and reasons for their loss to follow-up using a standard questionnaire, we could not confirm whether anything they said was true.
In this paper, we have reported the tracking of patients with glaucoma lost to follow-up in order to assess their true status and the reasons and factors for it. Approximately half of those patients had treatment interruptions, and the two main reasons cited for loss to follow-up involving treatment interruptions were lack of understanding regarding the necessity of follow-up and unawareness of the appointment schedule. These findings highlight the general lack of communication between physicians (or hospitals) and patients. Given the unpredictable course of glaucomatous disease, the only reliable means of distinguishing patients who are likely to have poor outcomes from the many who are not is to make sure that all patients are seen at prescribed regular intervals.22 Therefore, new strategies for ongoing educational support as well as improving appointment notification are necessary. Ophthalmologists must now recognise that loss to follow-up among patients with glaucoma is a major challenge to the delivery of effective care.
References
Footnotes
Contributors All of the authors made substantial contributions to this paper. KHP designed the study, monitored the data collection and revised the paper. JWJ and YKK conducted the study, collected the data, wrote the statistical analysis plan and drafted and revised the paper.
Competing interests None.
Patient consent Obtained.
Ethics approval This study followed the tenets of the Declaration of Helsinki, and was approved by the Institutional Review Board of Seoul National University Hospital.
Provenance and peer review Not commissioned; externally peer reviewed.
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