Bone mineral density, body mass index and cigarette smoking among Iranian women: implications for prevention

Table 2 Univariate association between individual risk factors and bone mineral density

Factor	LSBMD (g/cm²)		FNBMD (g/cm²)
	β ± SE ^a	R^2b	β ± SE^a	R^2b
Age (per 1 year)	-0.009 ± 0.002*	0.20	-0.008 ± 0.001*	0.25
Height (per -5 cm)	0.04 ± 0.012*	0.07	0.030 ± 0.010*	0.07
Weight (per -5 kg)	0.02 ± 0.005*	0.10	0.015 ± 0.005*	0.14
BMI (per -5 kg/m²)	0.035 ± 0.015*	0.05	0.030 ± 0.010*	0.07
Post-menopause	-0.153 ± 0.033*	0.19	-0.103 ± 0.026*	0.15
Smoking (current and ex-smokers)	-0.100 ± 0.040*	0.06	-0.086 ± 0.030*	0.08
Duration of smoking (per 5 years)	-0.037 ± 0.015*	0.06	-0.031 ± 0.011*	0.07
Cigarette dose (per 10 cig/day)	-0.054 ± 0.019*	0.08	-0.038 ± 0.014*	0.07
Dairy calcium intake (per 300 mg/day)	0.020 ± 0.03	0.001	0.020 ± 0.03	0.02
Regular exercise (yes)	0.017 ± 0.042	0.002	0.044 ± 0.031	0.02
Alcohol use (yes)	0.004 ± 0.058	0.001	-0.021 ± 0.044	0.003

BMI, body mass index; LSBMD, lumbar spine bone mineral density; FNBMD, femoral neck bone mineral density.
* P < 0.05 (statistically significant)
^a Values are regression coefficients ± SE describing the change in bone mineral density (g/cm²) associated with the unit change in the risk factor
^b Coefficient of determination: the proportion of variation in bone mineral density explained by the variation in a risk factor

ISSN: 1471-2474