Table 3.

“Predictive model”: relationships of regional brain volumes (outcome variables) to frailty parameters, assessed by multiple regression analyses controlling for age, ICV and nadir CD4 count. Each frailty parameter (average grip strength, maximum grip strength, walking time) was considered separately. P- and β-values for each frailty parameter are listed along with the model’s adjusted R².

Dependent variable	Average grip strength			Maximum grip strength			Walking time
	p-value	β	R2	p-value	β	R2	p-value	β	R2
Caudate†	0.008	−0.46	0.42	0.007	−0.48	0.43	ns	-	-
Thalamus†	0.022	0.39	0.42	0.015	0.42	0.44	ns	-	-
Subcortical GM	ns	-	-	ns	-	-	0.036	−0.30	0.51
Cerebellar WM	ns	-	-	ns	-	-	<0.001	−0.60	0.41

Abbreviations: WM = white matter, GM = gray matter, ICV = intracranial volume, ns = not significant.

^†Associations between regional volumes and hand grip strength were virtually unchanged when nadir CD4 was replaced by BDI_TOT, BDI_SOM or BDI_CA. Depressive scores and walking time were highly correlated and therefore were not included simultaneously in the model.