Table 3.

Neurodegenerative Versus Cerebrovascular Pathologies and Declining Grip Strength and Gait Function

		Grip Strength Decline Estimates (SE), p-values			Gait Function Decline Estimates (SE), p-values
Group of Pathologies	Neuropathology	Model 1	Model 2	Model 3	Model 4	Model 5	Model 6
Neurodegenerative	Amyloid × Time	−0.082 (0.043), .057		−0.079 (0.043), .068	0.000 (0.001), .939		0.000 (0.001), .810
	Tangles × Time	−0.132 (0.038), <.001		−0.121 (0.039), .002	−0.002 (0.001), .018		−0.002 (0.001), .043
	TDP-43 × Time	−0.229 (0.099), .020		−0.231 (0.010), .020	0.000 (0.001), .929		−0.002 (0.002), .343
	Hippocampal sclerosis × Time	−0.245 (0.146), .093		−0.222 (0.147), .130	0.000 (0.003), .931		0.001 (0.003), .864
	Lewy bodies × Time	−0.153 (0.105), .144		−0.166 (0.105), .113	−0.001 (0.002), .649		−0.001 (0.002), .564
	Nigral neuronal loss × Time	−0.402 (0.140), .004		−0.389 (0.140), .006	−0.009 (0.003), .002		−0.009 (0.003), .003
Cerebrovascular disease	Macroinfarcts × Time		−0.145 (0.096), .129	−0.153 (0.093), .101		−0.008 (0.002), <.001	−0.009 (0.002), <.001
	Microinfarcts × Time		−0.039 (0.096), .686	−0.063 (0.093), .495		−0.002 (0.002), .410	−0.002 (0.002), .379
	Atherosclerosis × Time		−−0.027 (0.101), .793	−0.011 (0.099), .912		−0.005 (0.002), .011	−0.005 (0.002), .019
	Arteriolosclerosis × Time		−0.209 (0.100), .038	−0.141 (0.099), .156		−0.004 (0.002), .059	−0.003 (0.002), .121
	Cerebral amyloid angiopathy × Time		−0.240 (0.090), .008	−0.075 (0.093), .419		−0.003 (0.002), .076	−0.002 (0.002), .290
Model-derived variance component
Variance in the person-specific motor function decline rate		1.095 (0.086), <.001	1.199 (0.092), <.001	1.095 (0.086), <.001	0.000410 (0.000040), <.001	0.000389 (0.000039), <.001	0.000381 (0.000039), <.001

Notes: SE = standard error; TDP-43 = transactive response DNA binding protein-43. Each model shows a single mixed-effects model with the outcome of grip strength decline (Models 1–3) or gait function decline (Models 4–6). The terms for pathologies included in each model were different: either neurodegenerative (Model 1 or 4), cerebrovascular disease pathologies (Model 2 or 5), or both together (Model 3 or 6). Each model included a term for time (rate of change in motor function) with cross-sectional terms for age at death, sex, education and each of the pathologies listed in the left column as well as their interaction with time. Each cell in a column shows the Estimate, SE, and p-value for the interaction of the pathology with time to show whether the pathology metric was associated with either grip strength or gait function decline rate. Bolded cells were significant. The last 2 rows indicate variance of the person-specific grip strength (Models 1–3) and gait function (Models 4–6) decline rates derived from the corresponding models, which were used to determine the percentage of variance in a motor function decline rate explained by pathologies. For example, the variance of the person-specific rate of grip strength decline derived from the core model, including no pathology, is 1.215 and from the model 1 including the neurodegenerative pathologies is 1.095. The variance of the rate of grip strength decline explained by the neurodegenerative pathologies is calculated in the following way: (1.215–1.095)/1.215 = 0.099 or 9.9%.