JOINT MODELING OF LONGITUDINAL INTRAOCULAR PRESSURE CHANGE AND TIME TO BLINDNESS OF GLAUCOMA PATIENTS AT FELEGE HIWOT REFERRAL HOSPITAL, BAHIR DAR, ETHIOPIA

MITIKU, WALE

dc.contributor.author	MITIKU, WALE
dc.date.accessioned	2019-09-25T05:39:41Z
dc.date.available	2019-09-25T05:39:41Z
dc.date.issued	2019-09-25
dc.identifier.uri	http://hdl.handle.net/123456789/9761
dc.description.abstract	ABSTRACT Background: Due to the substantial increase in the projected number of glaucoma cases within the next several decades, glaucoma is a significant public health issue. The main objective of this study was joint modeling of longitudinal intraocular pressure change and time to blindness of glaucoma patients at Felege Hiwot Referral Hospital, Bahir dar, Ethiopia. Method: A retrospective cohort study design was conducted from 328 randomly selected glaucoma patients in ophthalmology clinic at FHRH under the follow-up period from January 2014 up to December 2018. The analysis consists of exploratory data analysis and fitting three different models namely; a linear mixed effects model for the longitudinal data, a semiparametric survival model for the time-to-event data and a joint modeling of the two responses linked by shared random effects. Result: The use of a joint analysis compared to separate models shows a reduction in the standard errors which indicates that more adequate and efficient inferences can be made by using joint model estimates. The overall performance of both the separate and joint models in terms of model parsimony and goodness of fit, the joint model was performed better based on its lower AIC, BIC and based on a significant likelihood ratio test as well. The estimated association parameter (α) in the joint model is 0.0160 and statistically significant (p - value =0.0349). This indicated that there is strong evidence of association between the effects of the longitudinal intraocular pressure to the risk of blindness. The result indicated that the higher value of intraocular pressure was associated with the higher risk of blindness. For a unit increased in age, the average IOP of the patients was significantly increased by 0.0726 mmHg (p-value < 0.0001) keeping all variables constant. Conclusion: The predictor age, blood pressure, type of medication and cup-disk ratio were significantly associated with the two responses of glaucoma patients. Health professionals give more attention for patients who have blood pressure and cup-disk ratio greater than 0.7 during the follow-up time to reduce intraocular pressure and to minimize the risk of blindness of glaucoma patients. Keywords: Intraocular pressure, time to blindness, linear mixed model, joint model, Cox proportional hazard model	en_US
dc.language.iso	en	en_US
dc.subject	Statistics	en_US
dc.title	JOINT MODELING OF LONGITUDINAL INTRAOCULAR PRESSURE CHANGE AND TIME TO BLINDNESS OF GLAUCOMA PATIENTS AT FELEGE HIWOT REFERRAL HOSPITAL, BAHIR DAR, ETHIOPIA	en_US
dc.type	Thesis	en_US