Prevalence and individual risk factors associated with clinical lumbar instability in rice farmers with low back pain

Figures & data

Figure 1 Percentage of rice farmers with positive response to each question.

Notes: ■ Represents the rice farmers with LBP (n=282); □ represents the rice farmers with LBP who scored at least 7 out of 13 on subjective examination (n=41).
Abbreviation: LBP, low back pain.

Table 1 The demographic characteristics of the 323 rice farmers

Demographic characteristics	Mean	SD	Minimum	Maximum
Age (years)	43.93	10.42	20	60
Weight (kg)	58.63	12.18	38	92
Height (cm)	158.48	5.79	140	192
BMI (kg/m^2)	23.04	4.88	16.41	34.96
Waist-hip ratio	0.88	0.06	0.71	1.03
Farming experience (years)	24.29	12.38	1	58

Abbreviations: BMI, body mass index; SD, standard deviation.

Table 2 The independent variables of the rice farmers who had CLI and χ² before inclusion in initial model

Independent variables	Mean	SD	Total farmers		CLI		χ^2	P-value
			n	%	n	%
Sex							0.07	0.795
• Male			140	43.34	17	12.14
• Female			183	56.66	24	13.11
Age (years)	44.20	9.51					2.62	0.105*
• <45 years			151	46.75	24	15.89
• ≥45 years			172	53.25	17	9.88
BMI (kg/m^2)	23.21	3.45					2.09	0.148*
• <23 kg/m^2			168	52.01	17	10.12
• ≥23 kg/m^2			155	49.99	24	15.48
Waist-hip ratio	0.88	0.06					0.53	0.466
• M <0.9, F <0.8			119	36.84	13	10.92
• M ≥0.9, F ≥0.8			204	63.16	28	13.73
Smoking							1.20	0.272
• No			221	68.42	25	11.31
• Yes			102	31.58	16	15.69
Farming experience (years)	24.29	12.38					4.72	0.030*
• <30 years			177	54.80	16	9.04
• ≥30 years			146	45.20	25	17.12

Note:

* P-value <0.2.

Abbreviations: CLI, clinical lumbar instability; M, male; F, female; BMI, body mass index; SD, standard deviation.

Table 3 Risk factors associated with clinical lumbar instability in rice farmers with chronic non-specific low back pain: univariate and multiple regression analysis (n=41)

Characteristics	ORcrude		ORadj
	(95% CI)	P-value	(95% CI)	P-value
Sex
• M	1
• F	1.09 (0.57 to 2.10)	0.795
Age (years)
• <45 years	1		1
• ≥45 years	0.58 (0.30 to 1.12)	0.105	0.54 (0.27 to 1.06)	0.073
BMI
• <23 kg/m^2	1		1
• ≥23 kg/m^2	1.63 (0.84 to 3.13)	0.148	1.76 (0.89 to 3.47)	0.105
Waist-hip ratio
• M <0.9, F <0.8	1
• M ≥0.9, F ≥0.8	1.30 (0.65 to 2.59)	0.466
Smoking
• No	1
• Yes	1.46 (0.75 to 2.85)	0.272
Farming experience (years)
• <30 years	1		1
• ≥30 years	2.08 (1.07 to 4.03)	0.030	2.02 (1.03 to 3.98)	0.041*

Note:

* P-value <0.05.

Abbreviations: BMI, body mass index; OR, odds ratio; OR_adj, adjusted odds ratio; CI, confidence interval; M, male; F, female.