Development of a regression model using socio-demographic, behavioural and occupational risk factors for lumbar disc herniation (LDH) and lumbar disc degeneration (LDHD)-A case control study.

Abstract

Background: Although many studies have been conducted on risk factors associated with lumbar disc herniation (LDH), only few studies reported on the association of these factors in comparison to LDH and lumbar disc herniation and degeneration (LDHD). There are no reported studies on a regression model incorporating these factors. As the risk factors are better described in regression models, present study aimed to develop a regression model associated with LDH and LDHD in relation to socio-demographic, behavioural and occupational factors.Methods: A case control study conducted using 104 cases with LDH and controls (n=104) without LDH. Pre-tested questionnaire was administered to all participants to gather information.Results: Among the cases with LDH, 35.6 % presented with LDHD while 64.4 % had only LDH. Among the socio-demographic characteristics, body mass index <25 kgm-2 was a significant protective factor for both LDHD (OR=0.31; 95% CI=0.13-0.72) and LDH (OR=0.39; 95% CI=0.20-0.77). Involvement in daily activities with heavy (OR=5.1; 95 % CI=2.1-11.8) and moderate strain (OR=3.1; 95 % CI=1.5-6.6) to back, sitting more than eight hours per day (OR=5.1; 95 % CI=1.0-25.7), smoking (OR=5.0; 95 % CI=1.5-16.4) and sleeping in supine position (OR=2.09; 95% CI=1.09-4.06) were significant risk factors for LDH. Only daily physical activities with heavy strain act as a significant risk factor (OR=3.1; 95 % CI=1.1-8.5) for the development of LDHD. Types of mattresses used did not have significant difference among cases and controls. Majority of cases (56.7 %) did not know the causative factor that led to LDH. According to the regression model, BMI, smoking and involvement in physical activities with moderate and heavy strain to back were considered as significant risk factors for the development of LDH or LDHD.Conclusion: BMI, smoking and daily physical activities with moderate and heavy strain to back are significant risk factors for development of LDH or LDHD in regression model.