Turkiye Klinikleri Journal of Biostatistics

.: ORIGINAL RESEARCH
Survival Analysis of Glaucoma Patients Until Blindness: The Case of University of Gondar Comprehensive Specialized Hospital, Gondar, Ethiopia
Körlüğe Kadar Glokom Hastalarının Sağkalım Analizi: Gondar Üniversitesi Kapsamlı Özel Hastane Vakası, Gondar, Etiyopya
Mulu Tiruneh ASEMUa, Kasim Mohammed YESUFb, Yohannes Tadesse ASNAQEWb
aDepartment of Statistics, Debretabor University College of Natural & Computational Sciences, Debretabor, ETHIOPIA
bDepartment of Statistics, University of Gondar College of Natural & Computational Sciences, Gondar, ETHIOPIA
Turkiye Klinikleri J Biostat. 2019;11(1):36-46
doi: 10.5336/biostatic.2019-64649
Article Language: EN
Full Text
ABSTRACT
 Objective: The objective of the study was to identify the best-fitted survival regression model and to find factors that accelerate the time of blindness of glaucoma patients in University of Gondar Comprehensive Specialized Hospital. Material and Methods: Secondary data was taken from the patient's card, collected from January 2014-April 2018 in the hospital. In this study 401 glacoma patients' record was considered. Kaplan-Meier survival analysis, Semiparametric and Parametric AFT model were applied to identify factors that lead blindness of glaucoma patients. Results: From the total 401 glaucoma patients 23.69% was blind. From the total sample 38.41% and 61.59% were female and male glaucoma patients, respectively. The median time of blindness for the two eyes or one eye was 16 months after confirmation of glaucoma disease. In the multivariable Weibull accelerated failure-time model it has found that age group (18-43) (TR =1.29233, CI: 1.039576 to 1.606536), advanced stage of glaucoma (TR =1.281674, CI: 1.096103 to 1.498662), duration of diagnosis 1-5 years (TR = 1.944649, CI: 1.332738 to 2.83751) and duration of diagnosis >= 6 years (TR = 2.683586, CI: 1.367533 to 5.26615) were significantly associated with the time to blindness. Conclusion: The multivariable Weibull model revealed that age, duration of diagnosis and stage of glaucoma were major factors that affect the survival probability of glaucoma patients. Finally, based on the results of the study we can conclude that the Weibull regression model was the best fitted parametric accelerated failure-time model for identifying the major factors related to glaucoma patients.

Keywords: Glaucoma; risk factor; survival model; time of blindness
ÖZET
 Amaç: Çalışmanın amacı, en iyi sağkalım regresyon modelini belirlemek ve Gondar Üniversitesi Kapsamlı Özel Hastanesi'ndeki glokom hastalarının körlük süresini hızlandıran faktörleri bulmaktır. Gereç ve Yöntemler: İkinci veri Ocak 2014-Nisan 2018 arasında hastane tarafından toplanan hasta kartlarından alınmıştır. Bu çalışmada 401 glokom hastasının kayıtları dikkate alınmıştır. Glokom hastalarında körlüğe neden olan faktörleri belirlemek için Kaplan-Meier sağkalım analizi, Yarıparametrik ve Parametrik AFT model uygulanmıştır. Bulgular: 401 glokom hastasının %23.69'u kördü. Glokom hastalarının %38.41'i kadın, %61.59'u erkekti. Glokom hastalığı tanısı konduktan sonra bir ya da iki göz körlüğünün medyan süresi 16 aydır. Çok değişkenli Weibull hızlandırılmış başarısızlık-zaman modelinde yaş grubu (18-43) (TR =1.29233, CI: 1.039576;1.606536), ilerlemiş glokom evresi (TR =1.281674, CI: 1.096103;1.498662), tanı süresi 1-5 yıl (TR = 1.944649, CI: 1.332738;2.83751) körlük süresi ile anlamlı olarak ilişkili bulunmuştur. Sonuç: Çok değişkenli Weibull modeli yaş, hastalık süresi ve glokom evresinin glokom hastalarının sağkalım olasılığını etkileyen başlıca faktörler olduğunu ortaya çıkarmıştır. Sonuç olarak, çalışma sonuçlarına göre Weibull regresyon modeli; glokom hastaları ile ilişkili başlıca faktörleri belirlemede en iyi tahmini veren parametrik hızlandırılmış başarısızlık-zaman modelidir.

Anahtar Kelimeler: Glokom; risk faktörü; sağkalım modeli; körlük süresi
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