Validation of the NIH Toolbox in Individuals with Neurologic Disorders

OBJECTIVE

Individuals with spinal cord injury (SCI), traumatic brain injury (TBI), and stroke experience a variety of neurologically related deficits across multiple domains of function. The NIH Toolbox for the Assessment of Neurological and Behavioral Function (NIHTB) examines motor, sensation, cognition, and emotional functioning. The purpose of this paper is to establish the validity of the NIHTB in individuals with neurologic conditions.

METHODS

Community-dwelling individuals with SCI (n = 209), TBI (n = 184), or stroke (n = 211) completed the NIHTB. Relative risks for impaired performance were examined relative to a matched control groups.

RESULTS

The largest group differences were observed on the Motor domain and for the Fluid Cognition measures. All groups were at increased risk for motor impairment relative to normative standards and matched controls. Fluid cognitive abilities varied across groups such that individuals with stroke and TBI performed more poorly than individuals with SCI; increased relative risks for impaired fluid cognition were seen for individuals in the stroke and TBI groups, but not for those in the SCI group. All three neurologic groups performed normally on most measures in the Sensation Battery, although TBI participants evidenced increased risk for impaired odor identification and the stroke group showed more vision difficulties. On the Emotion Battery, participants in all three groups showed comparably poor psychological well-being, social satisfaction, and self-efficacy, whereas the TBI group also evidenced slightly increased negative affect.

CONCLUSIONS

Data provide support for the validity of the NIHTB in individuals with neurologic conditions.

A non-thrombocytopenic bleeding disorder due to an IgG4-kappa anti-GPIIb/IIIa autoantibody

Autoantibodies in chronic immune thrombocytopenic purpura occasionally interfere with platelet function. We describe a patient with a normal platelet count who had clinically significant mucosal bleeding, a prolonged bleeding time and abnormal platelet aggregation. The patient had high titres of an IgG4 kappa autoantibody, directed to a cation-dependent epitope on platelet glycoprotein IIb/IIIa, which blocked the binding of fibrinogen and fibronectin to this complex. Corticosteroid treatment resulted in clinical improvement and a marked drop in autoantibody concentration. The lack of thrombocytopenia in this patient, despite high autoantibody levels, is best explained by the poor recognition of IgG4 antibodies by phagocytic cells.

Effects of dietary fat content, saturated fatty acids, and fish oil on eicosanoid production and hemostatic parameters in normal men

Populations that consume a diet rich in marine lipids have been reported to have a lower risk of coronary heart disease. However, some Western population groups with a high fish consumption continue to suffer elevated rates of coronary heart disease. Many of these individuals consume a diet rich in saturated fats in addition to the fish. To examine these possible dietary interactions we fed six healthy men diets that contained two levels of saturated fat (5% and 19% of energy). During 3-week periods the study subjects were given diets with a low-(25% of energy) and high-(39% of energy) fat content with and without inclusion of n-3 polyunsaturated or monounsaturated fatty acids (2% of energy). The effects of the n-3 fatty acids on the principal plasma lipid fractions were similar regardless of the saturated fat intake. Platelet function, as measured by the skin bleeding time, was inhibited when n-3 fatty acids were added to the low saturated-fat diet. In vivo thromboxane A2 production as assessed by urinary metabolites also declined (p < 0.01) during supplementation with n-3 fatty acids to a low-fat diet. Prostacyclin production were reduced on a low-fat diet compared to a high-fat diet regardless of supplementation with n-3 fatty acids. N-3 fatty acids stimulated the synthesis of modest amounts of thromboxane A3 and prostacyclin I3, on both the low and high saturated-fat diets. These studies showed that the effects of eicosapentaenoic and docosahexaenoic acids on platelet and vascular function and eicosanoid production are modulated by the content of saturated fatty acids in the diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Atelectasis affects the rate of arterial desaturation during obstructive apnea

Chronic hemodynamic disturbances are more profound in patients with obstructive sleep apnea when underlying lung disease with abnormal gas exchange (low arterial PO2) is present. Previous studies suggest that pulmonary gas exchange could influence the rate of fall of arterial oxygen saturation (dSaO2/dt) in obstructive sleep apnea. We postulated that abnormal gas exchange in the form of atelectasis would steepen dSaO2/dt and thereby lower nadir arterial oxyhemoglobin saturation (SaO2) for the same duration of apnea. Apneas were created by clamping an indwelling cuffed endotracheal tube at end expiration in eight spontaneously breathing adult baboons. Apneas of the same duration were then repeated during temporary endobronchial occlusion of one lobe of the lung. SaO2 and mixed venous O2 saturation were continuously monitored, and cardiac output was calculated. Worsening of pulmonary gas exchange during atelectasis was documented by an increase in calculated venous admixture from 10.5 +/- 0.8 to 25.0 +/- 0.7% (P less than 0.001). The dSaO2/dt was independent of apnea duration at 30, 45, and 60 s. During endobronchial occlusion, apnea dSaO2/dt increased 20%, and nadir SaO2 was significantly lower. Possible mechanisms for steepening of dSaO2/dt during atelectasis are discussed.

Increased activity of factor VII and factor VII-phospholipid complex measured using a Normotest system in subjects with hyperlipidemia

Coagulation factor VII and factor VII-phospholipid complex (factor VIIpl), an activated form of factor VII, were measured using a Normotest system in 128 patients with various types of hyperlipoproteinemias and in 45 control subjects. A positive correlation was found between both factors VII (p less than 0.001) and VIIpl (p less than 0.0001) and serum triglycerides. Similar correlations were established with very low density lipoproteins. A positive correlation was also observed between factor VIIpl and total cholesterol, whereas inverse correlations were found with high-density lipoproteins for both factors VII and VIIpl. No positive correlation could be found between low-density lipoproteins and factors VII and VIIpl. This study has shown that patients with hyperlipoproteinemias associated with high serum triglyceride levels, with or without high cholesterol levels, have increased activity of factors VII and VIIpl, both previously associated with an increased risk of coronary heart disease.