Differences between bone mineral density, lean and fat mass of HIV-positive and HIV-negative black women

Figures & data

Figure 1: Study methods and number of study participants for this study.

Table 1: Descriptive data for the total group (median, IQR)

Variable	n	HIV-negative	n	HIV-positive	p-value*
Age (years)	439	52 (47;59)	103	47 (42;53)	< 0.001
BMI (kg/m^2)	439	30.5 (25;36)	103	24.7 (21;31)	< 0.001
Waist circumference (cm)	439	90.3 (79;100)	103	79.1 (70;88)	< 0.001
Fat percentage (%)	439	41.8 (36;46)	103	36.2 (29;41)	< 0.001
Fat (kg)	439	30.7 (22;39)	103	21.4 (15;30)	< 0.001
Whole-body BMD (g/cm^2)	439	1.06 (0.98;1.14)	103	1.04 (0.98;1.12)	0.03
LFN BMD (g/cm^2)^+	145	0.80 (0.67;0.85)	25	0.67 (0.63;0.83)	0.053
Spine BMD (g/cm^2)^+	145	0.88 (0.78;0.94)	25	0.78 (0.73;0.86)	0.005
Appendicular skeletal mass (ASM) (kg)	439	17.44 (14.46;20.02)	103	15.44 (13.24;17.88)	< 0.001
ASM index (kg/m^2)	439	7.02 (6.04;8.07)	103	6.35 (5.50; 7.31)	< 0.001
Smokers (%)	439	24.4%	103	20.4%	0.31
Alcohol (g)	439	0 (0;12.2)	103	3.4 (0;27)	0.10
Physical activity (PA) index (score)	150	2.99 (2.62;3.15)	33	2.93 (2.64;3.26)	0.12

Notes: Median and interquartile ranges (25th, 75th percentiles) are indicated for non-normally distributed data; *p-values reflect significant differences between the two groups; Mann–Whitney test or chi-square for categorical data; ⁺missing for some variables, LFN = left femoral neck, BMD = bone mineral density, BMI = body mass index.

Table 2: Matched data for HIV-negative and HIV-positive groups

Variable	HIV-negative n = 103	HIV-positive n = 103	p-value*
Age (years)	48 (45;53)	48 (43;54)	0.28
Weight (kg)	61.6 (52;75)	60.8 (51;76)	0.67
Height (cm)	157.4 (152;161)	156.5 (152;160)	0.37
BMI (kg/m^2)	25.1 (21;31)	24.7 (21;31)	0.85
Waist circumference (cm)	79.5 (71;93)	79.1 (71;88)	0.66
Fat percentage (%)	36.9 (32;42)	36.2 (30;42)	0.32
Body fat (kg)	22.2 (16;31)	21.4 (15;30)	0.37
BMD (g/cm^2)	1.02 (0.97;1.14)	1.03 (0.95;1.09)	0.44
Spine BMD (g/cm^2)*	0.88 (0.78;0.94)	0.78 (0.73;0.86)	0.05
LFN BMD (g/cm^2)*	0.80 (0.67;0.85)	0.67 (0.63;0.83)	0.09
Appendicular skeletal mass (ASM) (kg)	15.56 (13.27;18.44)	15.4 (13.24; 17.84)	0.75
ASM index (kg/m^2)	6.33 (5.51; 7.19)	6.35 (5.50; 7.28)	0.98
Trunk fat (kg)	10.37 (6.51;14.18)	9.21 (6.55;13.93)	0.50
Peripheral fat (kg)	12.25 (8.13;16.03)	11.32 (7.82;15.63)	0.44

Notes: Median and interquartile ranges (25th; 75th percentiles) are indicated for non-normally distributed data; p-values reflect significant differences between the two groups, Mann–Whitney test or chi-square for categorical data; *spine and LFN BMD data were available only for 25 HIV-positive women and 45 HIV-negative women.

Table 3: Multiple regression models for the association with whole BMD, spine BMD and LFN BMD in the total group (n = 542)*

Model	Standardised β	p-value
LFN hip BMD:
Final model, adjusted R^2 = 0.396		< 0.001
Body mass index (kg/m^2)	0.536	< 0.001
Dietary calcium intake (mg)	0.099	0.10
Weighted physical activity score	0.090	0.15
Age (years)	−0.222	< 0.001
HIV status (HIV-negative as reference)	−0.094	0.14
Spine BMD:
Final model, adjusted R^2 = 0.304		< 0.001
Body mass index (kg/m^2)	0.406	< 0.001
Smoking (non-smoking as the reference)	−0.135	0.04
Dietary calcium intake (mg)	0.093	0.16
Age (years)	−0.220	< 0.001
HIV status (HIV-negative as reference)	−0.146	0.03
Whole-body BMD:
Final model, adjusted R^2 = 0.386		< 0.001
Body mass index (kg/m^2)	0.495	< 0.001
Smoking (non-smoking as the reference)	−0.066	0.30
Dietary calcium intake (mg)	0.138	0.02
Age (years)	−0.253	< 0.001
HIV status (HIV-negative as reference)	−0.092	0.15

*Missing data for some variables; LFN = left femoral neck.

Table 4: Multiple regression models for the association with whole BMD, spine BMD and LFN BMD in HIV-negative and HIV-positive groups

Dependent variable: Whole-body BMD	HIV-positive group (n = 33)		HIV-negative group (n = 150)
Independent variables:	Standardised β	p-value	Standardised β	p-value
Education level (no school as reference)	0.301	0.02	–	–
Age (years)	−0.731	< 0.001	−0.201	0.002
Body mass index (kg/m^2)	–	–	0.541	< 0.001
Dietary calcium intake (mg/day)	–	–	0.143	0.03
Final model adjusted R square	0.725		0.386
Dependent variable – spine BMD:*	HIV-positive group		HIV-negative group
Independent variables:	Standardised β	p-value	Standardised β	p-value
Age (years)	−0.443	0.006	−0.172	0.02
Education level (no school as reference)	0.438	0.005	–	–
Alcohol intake (g/day)	0.355	0.019	–	–
Body mass index (kg/m^2)	–	–	0.436	< 0.001
Smoking (non-smoking as reference)	–	–	–0.151	0.04
Dietary calcium intake (mg/day)	–	–	0.074	0.30
Final model adjusted R-square	0.651		0.294
Dependent variable – LFN BMD:*	HIV-positive group		HIV-negative group
Independent variables:	Standardised β	p-value	Standardised β	p-value
Body mass index (kg/m^2)	0.484	0.009	0.569	< 0.001
Smoking (non-smoking as reference)	0.277	0.156	–	–
Education (no school as reference)	0.487	0.013	−0.102	0.129
Alcohol intake (g/day)	0.372	0.049	–	–
Dietary calcium intake (mg/day)	–	–	0.122	0.06
Weighted physical activity score	–	–	0.096	0.15
Age (years)	–	–	−0.228	0.001
Final model adjusted R square	0.452		0.411