Table 2.

The logistic regression analysis of the association between FM and LBP.

	Crude model	Adjusted model 1	Adjusted model 2
	OR (95% CI) P	OR (95% CI) P	OR (95% CI) P
Trunk FM (kg)	1.032 (1.026, 1.038) < .00001	1.031 (1.024, 1.037) < .00001	1.028 (1.021, 1.034) < .00001
Trunk FM (kg) quartile
Q1	Reference	Reference	Reference
Q2	1.172 (1.048, 1.310) .00538	1.186 (1.059, 1.328) .00325	1.220 (1.088, 1.369) .00069
Q3	1.224 (1.095, 1.368) .00036	1.232 (1.099, 1.382) .00036	1.232 (1.096, 1.386) .00047
Q4	1.697 (1.521, 1.894) < .00001	1.670 (1.493, 1.868) < .00001	1.608 (1.430, 1.809) < .00001
P for trend	<.0001	<.0001	<.0001
Right leg FM (kg)	1.084 (1.065, 1.103) < .00001	1.076 (1.055, 1.097) < .00001	1.075 (1.053, 1.097) < .00001
Right Leg FM (kg) quartile
Q1	Reference	Reference	Reference
Q2	1.164 (1.041, 1.300) .00742	1.121 (1.002, 1.255) .04671	1.164 (1.038, 1.305) .00940
Q3	1.149 (1.028, 1.284) .01454	1.072 (0.953, 1.207) .24485	1.115 (0.989, 1.257) .07617
Q4	1.618 (1.450, 1.805) < .00001	1.507 (1.333, 1.704) < .00001	1.517 (1.337, 1.722) < .00001
P for trend	<.0001	<.0001	<.0001
Left leg FM (kg)	1.086 (1.066, 1.106) < .00001	1.077 (1.055, 1.099) < .00001	1.076 (1.053, 1.099) < .00001
Left leg FM (kg) quartile
Q1	Reference	Reference	Reference
Q2	1.193 (1.067, 1.333) .00186	1.149 (1.026, 1.286) .01631	1.197 (1.067, 1.343) .00212
Q3	1.202 (1.076, 1.343) .00115	1.123 (0.998, 1.263) .05430	1.169 (1.036, 1.318) .01119
Q4	1.604 (1.438, 1.790) < .00001	1.497 (1.324, 1.693) < .00001	1.506 (1.327, 1.710) < .00001
P for trend	<.0001	<.0001	<.0001

Bold values indicate statistically significant difference at P < .05.

Crude model: no covariates were adjusted.

Adjusted model 1: age, gender, and race were adjusted.

Adjusted model 2: age, gender, race, education, PIR, activity, smoke, alcohol, hypertension and diabetes were adjusted.

FM = fat mass, LBP = low back pain, OR = odds ratio, PIR = poverty income ratio.