Browsing by Author "Racette, Lyne"

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    An Assessment of the Fidelity of Two Different Interventions to Improve Adherence to Glaucoma Treatment in Patients of African Descent
    (Office of the Vice Chancellor for Research, 2015-04-17) Idowu, Eniola; Bigatti, Silvia M.; Racette, Lyne
    Glaucoma is a chronic eye disease, which is asymptomatic and can slowly lead to blindness if left untreated. Glaucoma is caused by damage to the optic nerve and can lead to irreversible loss of sight. The overall objective of this MURI study was to determine the impact of two different interventions on compliance to glaucoma medication in patients of African descent with open-angle glaucoma. Two types of intervention were used – Education and Motivational Interviewing (MI). The educational intervention involved sharing knowledge with patients about glaucoma, its causes, and its treatments, to help patients better understand glaucoma and the importance of adhering to the daily medication regimen. The MI intervention involved communicating with the patients and encouraging them to identify strategies that would help them better adhere to their medications. These sessions were video-recorded and the content of each video was transcribed verbatim. The transcripts were then scored to assess the fidelity of each session with the intervention type that was given; this was done to ensure that each patient in the MI group received intervention consistent with MI, and that each patient in the Education group received an intervention free of MI. The standard Motivational Interviewing Treatment Integrity 3.0 coding sheet was used to code the MI and Education sessions. Global ratings were given for empathy, direction, collaboration, evocation and autonomy/support on a scale ranging from 1 (Low) to 5 (High). The following behaviors were counted within each transcript: giving information, MI adherent (asking permission, affirm, emphasize control, support), MI Non-adherent (advise, confront, direct), questions (closed questions, open questions), and reflections (simple, complex). We expect that the MI interventions would have significantly higher scores on MI adherent behaviors and significantly lower on MI-non-adherent behaviors compared to the Education session.
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    Characterizing and quantifying the temporal relationship between structural and functional change in glaucoma
    (Public Library of Science, 2021-04-01) Chu, Fang-I; Racette, Lyne; Ophthalmology, School of Medicine
    Purpose: To characterize and quantify the temporal relationship between structural and functional change in glaucoma. Methods: 120 eyes of 120 patients with ocular hypertension or primary open-angle glaucoma were selected from the Diagnostic Innovations in Glaucoma Study or the African Descent and Glaucoma Evaluation Study. Patients had 11 visits, separated by at least 3 months over 5 to 10 years. Each visit had rim area (RA) and mean sensitivity (MS) measurements taken within a 30-day period. The structure-function (SF) relationship was summarized using conventional and modified cross-correlation functions (CCFs), which identified the strongest absolute and positive correlation, respectively. Patients were categorized in one of the following three groups: RA and MS evolved simultaneously (lag = 0), RA preceded MS (lag<0), and MS preceded RA (lag>0). Lagging regression analysis was used to examine the variations of the SF relationship within groups. Results: The number of participants, mean visit lag, and mean correlation (standard deviation) were, for the conventional and modified CCFs, respectively: lag = 0 [16, 0, 0.53 (0.10) and 16, 0, 0.46 (0.11)]; lag<0 [50, -2.94, 0.51 (0.11) and 55, -3.45, 0.44 (0.12)], and lag>0 [54, 3.35, 0.53 (0.13) and 49, 3.78, 0.45 (0.12)]. A significant difference of the visit lag relation within groups was identified using lagging regression analysis (p<0.0001). Conclusions: The strongest relationship between structure and function was obtained at different visit lags in different patients. This finding also suggests that the SF relationship should be addressed at the subject level when using both measurements jointly to model glaucoma progression.
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    Comparison of matrix frequency-doubling technology perimetry and standard automated perimetry in monitoring the development of visual field defects for glaucoma suspect eyes
    (PLOS, 2017-05-18) Hu, Rongrong; Wang, Chenkun; Racette, Lyne; Ophthalmology, School of Medicine
    BACKGROUND: Perimetry is indispensable for the clinical management of glaucoma suspects. Our goal is to compare the performance of standard automated perimetry (SAP) and Matrix frequency-doubling technology (FDT) perimetry in monitoring the development of visual field (VF) defects in glaucoma suspect eyes. METHODS: Longitudinal data of paired SAP and FDT from 221 eyes of 155 glaucoma suspects enrolled in the Diagnostic Innovations in Glaucoma Study or the African Descent and Glaucoma Evaluation Study were included. All eyes had glaucomatous optic neuropathy or ocular hypertension, but normal SAP and FDT results at baseline. The development of glaucomatous VF defects was defined as the presence of a cluster of ≥ 3 (less conservative) or ≥ 4 (more conservative) locations confirmed on ≥ 2 additional consecutive tests. Risk factors for the development of VF defects were analyzed by COX proportional hazard models. After conversion into common logarithmic units, the rates of change of global VF indices were fitted with linear mixed models. RESULTS: FDT detected more eyes that developed VF defects than SAP using the less conservative criterion, and no significant difference was observed using the more conservative criterion. For those eyes detected by both SAP and FDT, FDT detected the development of VF defects either earlier than SAP or simultaneously in most cases. Baseline structural measurements were not significantly associated with an increased risk for the development of glaucomatous VF defects on either SAP or FDT. Older age was significantly associated with the development of VF defects on FDT but not on SAP. Both SAP and FDT detected a progressing worsening trend of pattern standard deviation over time with a similar rate of change between these test types. CONCLUSIONS: Matrix FDT would be useful to monitor the onset of VF defects in glaucoma suspects and may outperform SAP in the early stage of glaucomatous VF damage.
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    A Comparison of Objectively- and Subjectively-Measured Adherence in Glaucoma Patients of African Descent
    (Office of the Vice Chancellor for Research, 2015-04-17) Awan, Nabeel; Sutaria, Ankita; Bigatti, Silvia M.; Sirk, Emily; Hosty, Elizabeth; Payton, Chloe; Grow, Shelbi; Sutton, Bradley; Torbit, Julie; Racette, Lyne
    Purpose. Adherence to medical treatment of glaucoma is challenging. People of African descent (AD) have higher prevalence of open-angle glaucoma (OAG) and have been shown to have worse adherence. The goal of this prospective, observational study was to compare objectively- and subjectively-measured adherence in patients of African descent and to determine their relationship with self-efficacy. Methods. Twenty-one patients of AD diagnosed with OAG in the past five years were included in this study. Patients used a once-daily topical prostaglandin analog eye drop and self-administered their medication. Subjective adherence was assessed through self-report. Adherence was objectively measured using MEMS bottles. The cap of these bottles records the number of times the bottle is opened. Self-efficacy was assessed using the 10-item Glaucoma Medication Self-Efficacy scale and the 6-item Eye Drop Technique Self-Efficacy scale. MEMS adherence percentages were compared to self-reported adherence using a paired sample two-tailed t-test. To assess the relationship between objectively measured adherence and self-efficacy, patients were divided into 3 groups (n=7 each): high, medium and low adherence groups. The Chi-square test was used to determine whether differences in self-efficacy between the groups were present for each question on the two self-efficacy scales. Results. Subjectiveadherence (mean ± standard deviation) (97.34% ± 5.61) was significantly higher than objective adherence (66.34% ± 26.68) (p= 0.01). Of the 21 patients, 17 self-reported higher adherence levels than MEMS adherence levels. 4 patients with the highest levels of objectively measured adherence were the only patients to correctly estimate their adherence by self-report. Only one question was significantly associated with objective adherence: patients with high adherence were significantly more confident about taking their glaucoma medications when they do not experience symptoms (p = 0.04). Conclusions. Results showed that patients with higher adherence are more confident about using their eye drops in the absence of symptoms.
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    Comparison of retinal nerve fiber layer and macular thickness for discriminating primary open-angle glaucoma and normal-tension glaucoma using optical coherence tomography
    (Wiley, 2016-07) Khanal, Safal; Davey, Pinakin Gunvant; Racette, Lyne; Thapa, Madhu; Department of Ophthalmology, IU School of Medicine
    Purpose The aim of this study was to evaluate the discrimination capabilities of macular and peripapillary retinal nerve fiber layer (pRNFL) thickness parameters as measured using spectral domain optical coherence tomography (SD-OCT) between primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG). Methods A total of 90 subjects were enrolled: 30 healthy subjects, 30 subjects with POAG and 30 subjects with NTG, consecutively. Retinal nerve fiber layer thickness, macular thickness and volume measurements were obtained with circular and radial SD-OCT scans. All parameters were compared between groups using an analysis of variance test. Areas under receiver-operating characteristic (AROC) curves with sensitivities at specificities greater than or equal to 90 per cent were generated to compare discrimination capabilities of various parameters between POAG and NTG. Results Macular thickness and volume measurements were the highest in normal subjects, followed by NTG and POAG (p < 0.05). Average retinal nerve fiber layer thickness had perfect discrimination for normal-POAG (AROC: 1.000; sensitivity: 100 per cent) and near perfect discrimination for normal-NTG (AROC: 0.979; sensitivity: 93 per cent) as well as NTG-POAG pairs (AROC: 0.900; sensitivity: 60 per cent). Inferior outer macular thickness (IOMT) and total volume were the best macular thickness and volume parameters having similar AROCs and sensitivities between normal and POAG (IOMT, AROC: 0.987; sensitivity: 92 per cent and total volume, AROC: 0.997; sensitivity: 97 per cent), normal and NTG (IOMT, AROC: 0.862, sensitivity: 47 per cent and total volume, AROC: 0.898, sensitivity: 67 per cent) and also between NTG and POAG (IOMT, AROC: 0.910, sensitivity: 53 per cent and total volume, AROC: 0.922, sensitivity: 77 per cent). In each comparison group, there was no statistically significant difference in AROCs between average retinal nerve fiber layer and inferior outer macular thickness, as well as total volume. Conclusions The macular parameters offer comparable performance to pRNFL parameters for the discrimination of NTG and POAG. Average retinal nerve fiber layer thickness, total macular volume and inferior outer macular thickness were the best SD-OCT parameters with superior discriminating capabilities.
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    Determining the Impact of Demographic Factors on Adherence to Glaucoma Treatment in Patients of African Descent
    (Office of the Vice Chancellor for Research, 2015-04-17) Botros, Mark; Racette, Lyne; Bigatti, Silvia M.
    Primary open-angle glaucoma (POAG) affects approximately 2.5 million Americans. Elevated intraocular pressure (IOP) is the only treatable risk factor to slow the progression of the disease and prevent blindness. Topical ocular hypotensive medications, dispensed in the form of eye drops, are the first line of treatment to reduce IOP. Patients are required to use their eye drops once or twice daily throughout the rest of their lives. Patients of African descent are more vulnerable to this chronic disease, with a prevalence six times higher than patients of European descent. They also have worse adherence to the treatment regimen in general. The main purpose of this study was to determine the impact of education, age, gender, household income, marital status, employment and number of prescribed medications on the adherence to the glaucoma treatment. Twenty-one patients were included and adherence was measured using Medication Event Monitoring System caps, which electronically record every time a patient uses their eye drops. After 4 weeks, patients returned with the caps and the compliance level was recorded. During the initial interview, patients answered a questionnaire about the different factors tested in this study. There was a positive correlation between the compliance percentage and age, with patients who are 70 years or older having the highest compliance levels (82% compared to 62% in the 50s and 60s category). Education also affected compliance, with patients who have a high school degree having a lower compliance at 62% compared to the patients with some college or a bachelor’s degree with compliance of 81%. The employment status was another contributor, with higher compliance in full-time employed patients compared to other employment types. The remaining factors did not contribute to the adherence levels. Overall, education, age, and employment status were the only factors that impacted adherence levels.
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    Differences in Ocular Blood Flow Between People of African and European Descent With Healthy Eyes
    (Lippincott, Williams, and Wilkins, 2016-09) Kaskan, Betül; Ramezani, Koosha; Harris, Alon; Siesky, Brent; Olinde, Carine; WuDunn, Darrell; Eikenberry, Jennifer; Tobe, Leslie A.; Racette, Lyne; Department of Ophthalmology, IU School of Medicine
    Purpose: To investigate differences in ocular blood flow between people of African descent (AD) and European descent (ED) with healthy eyes. Materials and Methods: Retrobulbar and retinal capillary blood flow was assessed in 1 eye of 58 participants (24 AD, 34 ED) with healthy eyes with systemic blood pressure lower than 140/90. Retrobulbar blood flow was measured in the ophthalmic artery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA) and temporal posterior ciliary artery (TPCA). Peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index (RI) were assessed. Retinal capillary blood flow was assessed using mean retinal flow and avascular space defined as the percent of area measured with no blood flow. Groups were compared using t tests and Pearson correlations were compared using Fisher r-to-z transformation. Results: Compared with people of ED, people of AD had significantly lower EDV in the NPCA (P=0.01), and higher RI in the CRA (P=0.04) and TPCA (P=0.01). No significant differences were observed in mean retinal capillary flow or avascular area. In the CRA, a significant negative correlation was observed between pattern standard deviation and peak systolic velocity (P=0.02) in the AD group and this correlation was significantly different from that observed in the ED group (P=0.01). A significant correlation was also observed between pattern standard deviation and EDV (0.04) in the AD group. Conclusions: This study suggests that retrobulbar blood flow is lower in healthy eyes in persons of AD compared with ED. This may provide a mechanism through which people of AD are at increased risk for ophthalmic diseases such as glaucoma.
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    Differences in ocular blood flow in glaucoma between patients of African and European descent
    (Ovid Technologies (Wolters Kluwer) - Lippincott Williams & Wilkins, 2015-02) Siesky, Brent; Harris, Alon; Racette, Lyne; Abassi, Rania; Chandrasekhar, Kaarthik; Tobe, Leslie A.; Behzadi, Jennifer; Eckert, George; Amireskandari, Annahita; Muchnik, Michael; Department of Ophthalmology, IU School of Medicine
    PURPOSE: To investigate differences in ocular blood flow in individuals of African descent (AD) and European descent (ED) with open angle glaucoma (OAG). PATIENTS AND METHODS: A retrospective data analysis was performed on OAG patients of AD and ED who were previously examined for ocular blood flow within the Department of Ophthalmology at Indiana University School of Medicine. Data analysis included blood pressure, heart rate, visual fields, intraocular pressure, ocular perfusion pressure, and color Doppler imaging of retrobulbar vessels. Color Doppler imaging measurements were performed on ophthalmic, central retinal, and nasal and temporal short posterior ciliary arteries, with peak systolic (PSV) and end diastolic velocities (EDV) as well as the Pourcelot vascular resistive index calculated for each vessel. Two-sample t tests of unequal variance were performed with P values <0.05 considered statistically significant. RESULTS: OAG patients of AD had statistically significant lower retrobulbar blood flow values than patients of ED including lower ophthalmic artery PSV (P=0.0001), ophthalmic artery EDV (P=0.0008), central retinal artery PSV (P=0.01), temporal short posterior ciliary artery PSV (P=0.0037), and nasal short posterior ciliary artery PSV (P<0.0001). No significant differences were found in terms of intraocular pressure or visual field parameters. CONCLUSIONS: Significantly lower blood flow values were identified in all retrobulbar blood vessels in AD compared with ED OAG patients. These findings suggest that the contribution of ocular blood flow to the disease process may be different in AD compared with ED OAG patients.
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    Does Knowledge of the Causes of Glaucoma Impact Adherence?
    (Office of the Vice Chancellor for Research, 2016-04-08) Diallo, Kadé; Bigatti, Silvia M.; Sutton, Bradley; Torbit, Julie; Racette, Lyne
    Purpose: Glaucoma is informally known as loss of sight due to the deterioration or damage to the optic nerve; some scientists claim to have identified the genes related to these causes. The most prevalent risk factor includes those of African descendant. We tested the hypothesis that the adherence level is higher in patients with more knowledge of their condition than those with none. Methods: A dataset of the first visit from a clinical diagnosis of open-angle glaucoma was retrieved, in which all the patients administered once-daily prostaglandin analog eye drops themselves. Participants were on average 60.38±9.93yrs of age and identified as African descendants; of the 29 patients, 16 self-identified as male and the rest female. Participants were specifically asked to “Please list in rank-order the three most important factors that you believe caused your illness”. We grouped the results into three different conditions: (1) those with at least on “true” (current factors that are widely accepted scientifically) risk factors vs those with none, (2) those who included race as a risk factor vs those who did not, and (3) those who listed any risk factors vs those with none. We compared the adherence within each condition using two-tailed t-test to calculate the “level of significance”. Results: Our results did not agree with our hypothesis. The values returned were: (1) 0.1244, (2) 0.3744, and (3) 0.2516. Because all three results were ≥ 0.05, our data displayed that there were no relationship between the groups. It meant that our outcomes were most likely a consequence of chance with no significance. Conclusions: Though our results were not consistent with our hypothesis, we were still able to come to a different deduction: whether or not individuals are educated on the causes of their conditions, their adherence will only improve if they decide it so.
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    Does Knowledge of the Risk Factors of Glaucoma Impact Adherence in patients of African descent?
    (Investigative Ophthalmology and Visual Science Journal, 2016) Diallo, Kade; Bigatti, Silvia; Sutton, Bradley; Torbit, Julie; Racette, Lyne
    Purpose : The first line of treatment for primary open-angle glaucoma (POAG) is the daily use of eye drops. Adherence to this regimen is known to be challenging for patients. While POAG is more prevalent in people of African descent (AD), worse adherence is reported in this high-risk population. The purpose of this prospective clinical study was to determine whether knowledge of the risk factors associated with glaucoma translates into better adherence. Methods : Twenty-nine patients with POAG were included in the study. Participants were on average 60.38±9.93 years of age, identified as being of AD by self-report and 16 were male. Adherence was measured using Medical Event Monitoring System (MEMS) bottles. The cap of these bottles electronically records the date and time at which the bottle is opened. Each participant filled out the Brief Illness Perception questionnaire in which they were asked to “Please list in rank-order the three most important factors that you believe caused your illness”. The adherence of patients who reported 1) at least one accurate risk factor was compared to that of patients who reported no accurate risk factor, 2) race as a risk factor was compared to that of patients who did not report race, and 3) any risk factor (accurate or inaccurate) was compared to that of patients who reported no risk factor. Groups were compared using two-tailed t-tests. Results : Patients who reported at least one accurate risk factor (n=18) had similar adherence (73.39±25.94%) to those who reported no accurate risk factor (n=11) (55.91±33.10%) (p=0.12). Patients who reported race as a risk factor (n=6) had similar adherence (76.50±24.94%) to those who did not report race (n=23) (64.22±30.64%) (p=0.37). Patients reported any risk factor (n=22) had similar adherence (70.36±26.89%) to those who reported no risk factor (n=7) (55.43±36.78%) (p=0.25). While there was an overall trend for higher adherence in patients with more knowledge, statistical significance was not reached in any of the comparisons. Conclusions : We hypothesized that knowledge of the risk factors of glaucoma would result in better adherence because this knowledge could reflect a better understanding of the disease and of the importance of adhering to treatment. Our results suggest that knowledge of the risk factors of glaucoma does not impact adherence. Future studies will investigate whether educating patients can improve adherence.