Table 3. Bone disease.

Author, year, Location	Study design	Age	% male	HIV Virological Control	NCD Examined	Main findings
Mei 2023, USA	Cross sectional study of PWH and HIV negative. Primary analysis of gut microbiota, metabolites and BMD: 58 women HIV+, 33 HIV- women. Secondary analysis of gut microbiota and plasma metabolites: 280 HIV+ and 138 HIV-	Years (mean, SD) normal BMD (n = 60), 53.2+- 4.6, low BMD (n = 31), 55.0 +- 4.5	0	1. normal BMD 81.6% and 2. low BMD 85% undetectable/ suppressed viral load	BMD measured by DXA; Untargeted metabolic profiling- A total of 467 metabolites were included	No association between α-or β- diversity and BMD status. Five genera of the Clostridiales order (Dorea, Megasphaera, unclassified Lachnospiraceae, Ruminococcus, and Mitsuokella) were more abundant in women with low BMD, and one other (unclassified Mollicutes RF39) was less abundant in the low-BMD group compared with the normal-BMD group. Plasma serine was higher, whereas levels of the other 16 metabolites belonging to amino acids, carnitines, caffeine, fatty acids, pyridines, and retinoids were lower in women with low BMD compared with those with normal BMD, irrespective of HIV status. Megasphaera, were inversely associated with several BMD-related metabolites (e.g. 4-pyridoxic acid, C4 carnitine, creatinine, and dimethylglycine).

Abbreviations: BMD, bone mineral density; DXA, dual-energy X-ray absorptiometry