The effect of cigarette smoking and physical activity on the severity of primary open angle glaucoma in Malay patients

• Main Author: Leong, Tan Kok
• Format: Thesis
• Language: English
• Published: 2017
• Subjects: RE Ophthalmology
• Online Access: http://eprints.usm.my/45608/1/Dr.%20Tan%20Kok%20Leong-24%20pages.pdf; http://eprints.usm.my/45608/
• Institution: Universiti Sains Malaysia

INTRODUCTION Primary open angle glaucoma (POAG) is the most common type of glaucoma. Data regarding this disease among Malay population is scarce. Currently, intraocular pressure is the only modifiable risk factor of POAG that was consistent among past studies. Influence of lifestyle factors such as cigarette smoking and physical activity on the severity of POAG is still inconclusive. OBJECTIVE The aim of this study is to determine the association of cigarette smoking and physical activity with the severity of POAG among Malay patients in Malaysia. METHODOLOGY A cross sectional study involving Malay POAG patients was conducted between November 2014 and December 2016. The smoking status was documented using a validated Malay language questionnaire adopted from Singapore Malay Eye Studies (SiMES), which also has been used among glaucoma patients. The physical activity assessment was carried out using the validated Malay version of International Physical Activity Questionnaire (IPAQ). Humphrey visual field (HVF) 24-2 test was conducted. POAG severity was determined according to modified Advanced Glaucoma Intervention Study (AGIS) scoring system, based on two consecutive reliable HVF, by two masked investigators. Severity of POAG was catogerized into mild (score of 0 to 5), moderate (score of 6 to11) and severe (score of 11 to 20). Univariate analysis was done to evaluate risk factors associated with POAG. Theassociation of cigarette smoking, and physical activity level with AGIS score was analyzed using multiple linear regression. Confounders such as age, gender, education status, and systemic co-morbidities were considered in the analysis. RESULTS A total of 150 Malay patients with POAG were recruited; comprising of 101 males and 49 females. This study did not find any significant association between physical activity and the AGIS score of Malay POAG patients. There was a significant correlation between cigarette smoking status and the AGIS score (r = 0.175, p = 0.032) among Malay POAG patients. However, the duration of smoking was not found to be significantly correlated with the AGIS score (r = 0.142, p = 0.083). There was a positive linear relationship between age of POAG patient and AGIS score. CONCLUSION Cigarette smoking is a potential modifiable risk factor for POAG among Malays. This study found significant association of smoking status with POAG severity. However further study is needed to quantify the influence of smoking on POAG severity. POAG patient should be advised and properly educated to refrain from cigarette smoking, as smoking could to lead to more severe POAG and progression of the disease. There was no significant association between physical activity and severity of POAG in Malays. Limitation of cross sectional study and IPAQ may not reflect the actual influence of physical activity on the severity of POAG.