An analysis of the interactions between the spine, pelvis, and lower limbs in asymptomatic adults with limited pelvic compensation.

BACKGROUND: The interactions between the spine, pelvis, and lower limbs are dynamic based on the "cone of economy" concept; thus, different global radiographic parameters could be regarded as reflections of different centers of gravity. We conducted this retrospective study to evaluate the offsets of different centers of gravity in asymptomatic populations and to investigate how the global sagittal alignment is supported. METHODS: The following parameters were measured: cervical lordosis, thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), the ratio between PT and PI (PT/PI), sacral slope, PI minus LL (PI-LL), the sagittal vertical axis (SVA), cranial SVA to ankle center (Cr-A), CrSVA to the femoral head center (Cr-FH), C2SVA to the femoral head center (C2-FH), pelvic translation (P. Shift), and knee angle (KA). Participants were divided into subgroups based on the PT/PI ratio. Mean values were compared using the t-test, and correlations were assessed using Pearson's coefficient. RESULTS: A total of 82 asymptomatic adults were enrolled. The average PT/PI in subgroup 1 was the smallest, showing that individuals in this group may have limited pelvic retroversion. No significant differences in Cr-FH, Cr-A, or C2-FH were found between subgroups (all P>0.1), implying that global alignment was well supported in each group. Specifically, C2-FH showed minor changes between subgroups (P=0.998), showing that C2-FH may be a target for sagittal compensation. There were positive correlations between PT/PI and both P. Shift and SVA (r=0.930 and r=0.606, respectively). However, Cr-FH, Cr-A, and C2-FH were not significantly correlated with P. Shift or PT/PI (all P>0.05). Weak correlations existed between Cr-A, Cr-FH, and age (all P>0.2). CONCLUSIONS: This study revealed that the Cr-FH and C2-FH offsets are stable across the population and could be maintained by regulating only the sagittal spinal curvature when pelvic compensation is limited. Cr-FH is not affected by age in the asymptomatic population. Thus, the stable Cr-FH and C2-FH could provide references for surgeons during the surgical decision-making process in patients with adult spinal deformity with sagittal malalignment.

High white matter hyperintensity burden in strategic white matter tracts relates to worse global cognitive performance in community-dwelling individuals.

BACKGROUND: White matter hyperintensities (WMH) are associated with cognitive impairment. The impact of WMH on cognitive domains (e.g. processing speed, executive functioning) depends on location. We determined whether the relevance of WMH location also applies to global cognitive functioning by testing if WMH in strategic white matter tracts are associated with global cognitive functioning independent of total WMH burden. METHODS: We included 830 community-dwelling individuals. WMH volume within two a priori specified strategic white matter tracts (forceps minor and anterior thalamic radiation) were entered in a linear regression model with the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) as outcome variables and corrected for total WMH volume and other MRI markers for vascular injury and neurodegenerations (i.e. brain parenchymal fraction, and the presence of lacunes and microbleeds). RESULTS: WMH in the forceps minor and left anterior thalamic radiation inversely correlated with MoCA, and WMH in the forceps minor inversely correlated with MMSE, independent of total WMH volume and other MRI markers. CONCLUSION: The impact of WMH on global cognitive functioning depends on location. Whether this reflects accumulated impairment in isolated cognitive domains or disruption of a network that is crucially involved in global cognitive performance remains to be determined.

Global sagittal alignment in elderly patients with osteoporosis and its relationship with severity of vertebral fracture and quality of life.

We compared global sagittal alignment and quality of life in osteoporotic patients with and without vertebral compression fracture (VCF) and determined its relationship with VCF severity. The findings revealed osteoporotic patients with VCF showed decreased quality of life and worse global sagittal alignment, which was significantly associated with VCF severity. INTRODUCTION: The aim of this study was to compare the global sagittal alignment and quality of life in elderly osteoporotic patients with and without vertebral compression fracture (VCF), and to investigate the relationship between global sagittal alignment and severity of VCF. METHODS: A consecutive series of 72 female patients with osteoporosis aged over 60 years and 31 age-matched females without osteoporosis were prospectively enrolled. The patients were divided into VCF and non-VCF group. Patient's clinical demography, nature of VCF, and bone mineral density (BMD) were also recorded. Spinal deformity index was used to evaluate severity of VCF. EOS® biplanar imaging system was then used to evaluate global sagittal parameters: T1 pelvic angle (TPA) and global sagittal angle (GSA). In addition, quality of life was assessed with self-reported questionnaires: the Oswestry Disability Index (ODI) and Short-form 12 (SF-12). RESULTS: Osteoporotic patients and controls were found to be significantly different in terms of TPA, GSA, and BMD. And in patients with VCF, they were found to have significantly higher TPA and GSA. TPA and GSA were significantly correlated with SF-12 and ODI. The number of VCF and SDI significantly correlated with global sagittal alignment. Using regression analysis, parameters significantly associated with abnormal global alignment were the number of VCF (OR = 1.13) and SDI (OR = 1.84). CONCLUSION: Osteoporotic patients with VCF showed worse global sagittal alignment and decreased quality of life. The number and severity of VCF had a negative influence on global sagittal balance, which indicates that poorer sagittal global alignment may imply worse quality of life and more severe VCF.

The Additional Contribution of White Matter Hyperintensity Location to Post-stroke Cognitive Impairment: Insights From a Multiple-Lesion Symptom Mapping Study.

White matter hyperintensities (WMH) are common in acute ischemic stroke patients. Although WMH volume has been reported to influence post-stroke cognition, it is still not clear whether WMH location, independent of acute ischemic lesion (AIL) volume and location, contributes to cognitive impairment after stroke. Here, we proposed a multiple-lesion symptom mapping model that considers both the presence of WMH and AIL to measure the additional contribution of WMH locations to post-stroke cognitive impairment. Seventy-six first-ever stroke patients with AILs in the left hemisphere were examined by Montreal Cognitive Assessment (MoCA) at baseline and 1 year after stroke. The association between the location of AIL and WMH and global cognition was investigated by a multiple-lesion symptom mapping (MLSM) model based on support vector regression (SVR). To explore the relative merits of MLSM over the existing lesion-symptom mapping approaches with only AIL considered (mass-univariate VLSM and SVR-LSM), we measured the contribution of the significant AIL and/or WMH clusters from these models to post-stroke cognitive impairment. In addition, we compared the significant WMH locations identified by the optimal SVR-MLSM model for cognitive impairment at baseline and 1 year post stroke. The identified strategic locations of WMH significantly contributed to the prediction of MoCA at baseline (short-term) and 1 year (long-term) after stroke independent of the strategic locations of AIL. The significant clusters of WMH for short-term and long-term post-stroke cognitive impairment were mainly in the corpus callosum, corona radiata, and posterior thalamic radiation. We noted that in some regions, the AIL clusters that were significant for short-term outcome were no longer significant for long-term outcome, and interestingly more WMH clusters in these regions became significant for long-term outcome compared to short-term outcome. This indicated that there are some regions where local WMH burden has larger impact than AIL burden on the long-term post-stroke cognitive impairment. In consequence, SVR-MLSM was effective in identifying the WMH locations that have additional impact on post-stroke cognition on top of AIL locations. Such a method can also be applied to other lesion-behavior studies where multiple types of lesions may have potential contributions to a specific behavior.

White Matter Hyperintensity Predicts the Risk of Incident Cognitive Decline in Community Dwelling Elderly.

BACKGROUND: Unlike western countries, data on white matter hyperintensity (WMH) in community dwelling elderly in Asian population is very limited. OBJECTIVE: To examine the relation between baseline WMH burden and the risk of incident cognitive decline in a community-based cohort with Chinese-dwelling elderly. METHODS: We prospectively evaluated the incident cognitive decline for 226 participants in the Shanghai Aging Study. Baseline WMH severity was visually rated by the age-related white matter changes (ARWMC) scale based on MRI. Cox proportional hazards regression model was used to estimate the relative risk (RR) of total ARWMC scale, global ARWMC score, presence of lacune and microbleed, for incident cognitive decline by adjusting potential confounders. RESULTS: Forty subjects were identified with incident cognitive decline (new onset 34 mild cognitive impairment and 6 dementia) during a median duration of 6 years follow-up. The incidence of cognitive decline was 3.0 (95% confidence interval [CI] 2.2-4.1) per 100 person-years. Increasing total ARWMC scale [RR1.21 (95% CI 1.06-1.39), p = 0.004)], confluent WMH [RR3.16 (95% CI 1.50-6.64), p = 0.002), and presence of lacunes [RR 2.73 (95% CI 1.21-6.15)] at baseline were independent predictors of incident cognitive decline. CONCLUSION: Our study demonstrated that confluent WMH may increase the risk of incident cognitive decline by 3 folds in community dwelling subjects. Small vessel disease may cause heavy burden of cognitive impairment in the elderly in China.

Risk factors for incident dementia after stroke and transient ischemic attack.

BACKGROUND: We hypothesized that chronic brain changes are important substrates for incident dementia after stroke and transient ischemic attack (TIA). METHODS: We compared clinical and imaging features between patients with consecutive stroke/TIA with (n = 88) and without (n = 925) incident dementia at 3 to 6 months after a stroke/TIA. Pittsburg compound B (PiB) positron emission tomography was performed in 50 patients, including those with (n = 37) and without (n = 13) incident dementia. RESULTS: Age, history of diabetes mellitus, severity of white matter changes (WMCs), and medial temporal lobe atrophy (MTLA) were associated with incident dementia. Alzheimer's disease (AD)--like PiB retention was found in 29.7% and 7.7% (P = .032) of patients with and without incident dementia, respectively. CONCLUSIONS: Chronic brain changes including WMCs, MTLA, and AD pathology are associated with incident dementia after stroke/TIA. Interventions targeting these chronic brain changes may reduce burden of vascular cognitive impairment.

Prestroke statins, progression of white matter hyperintensities, and cognitive decline in stroke patients with confluent white matter hyperintensities.

Cerebral white matter hyperintensities (WMH) are a consequence of cerebral small vessel disease. Statins have been shown to reduce recurrent stroke among patients with various stroke subtypes, including lacunar stroke, which also arises from small vessel disease. In this study, we investigated the hypothesis that prestroke statin use would reduce the progression of WMH and/or cognitive decline among stroke patients with confluent WMH. Patients (n = 100) were participants of the VITAmins To Prevent Stroke magnetic resonance imaging substudy. All patients had confluent WMH on magnetic resonance imaging at baseline. Eighty-one patients completed the 2-year follow-up. We assessed general cognition and executive function using the mini-mental state examination and Mattis dementia rating scale-initiation/perseveration subscale, respectively. We compared the change in volume of WMH and cognition between prestroke statin use and prestroke nonstatin use groups. We also evaluated the effects of prestroke statin use on incident lacunes and microbleeds. The prestroke statin use group (n = 51) had less WMH volume progression (1.54 ± 4.52 cm(3) vs 5.01 ± 6.00 cm(3), p = 0.02) compared with the prestroke nonstatin use group (n = 30). Multivariate linear regression modeling identified prestroke statin use as an independent predictor of WMH progression (ß = -0.31, p = 0.008). Prestroke statin use was also associated with less decline (Mattis dementia rating scale-initiation/perseveration subscale; ß = 0.47, p = 0.001). No association was observed with changes in mini-mental state examination scores. There were no between group differences on incident lacunes or incident microbleeds. Prestroke statin use may reduce WMH progression and decline in executive function in stroke patients with confluent WMH.

Race-ethnicity and cerebral small vessel disease--comparison between Chinese and White populations.

BACKGROUND AND AIM: Studies in stroke patients suggest that lacunar stroke and intracerebral hemorrhage might be more common in Chinese than Whites. We hypothesized that other manifestations of subclinical cerebral small vessel disease, namely white matter hyperintensities (WMH), lacunes, and microbleeds, are also more common in Chinese than Whites. We compared the community prevalence of these lesions between Han Chinese and White Australians. METHODS: Magnetic resonance imaging (1·5-Tesla) was performed on participants of the Shanghai Aging Study (n = 321, mean age 69 ± 6 years) and Tasmanian Study of Cognition and Gait (n = 397, mean age 72 ± 7 years). A single-rater recorded measures of WMH, lacunes, and microbleeds. We compared lesion prevalence between age- and gender-matched subgroups from the two cohorts. Among all subjects (n = 718), we performed multivariable logistic regression to examine if race-ethnicity was independently associated with these lesions. RESULTS: Among age- and gender-matched subjects, confluent WMH were significantly more prevalent in Chinese (38·5%) than Whites (28·4%; P = 0·01). There was no difference in the prevalence of lacunes (Chinese 29·1% vs. Whites 29·5%, P = 0·93) and microbleeds (Chinese 10·1% vs. 9·0%, P = 0·67) between Chinese and Whites. In multivariable logistic regression, Chinese ethnicity was associated with confluent WMH (odds ratio 1·7, 95% confidence interval 1·1-2·6, P = 0·01), but no differences were seen for lacunes and microbleeds. The association between Chinese ethnicity with confluent WMH became insignificant when subjects with history of stroke were excluded. CONCLUSIONS: In this population-based cross-national comparison, Han Chinese had a higher prevalence of confluent WMH than White Australians, but had a similar prevalence of lacunes and microbleeds.

The NINDS-Canadian stroke network vascular cognitive impairment neuropsychology protocols in Chinese.

BACKGROUND AND PURPOSE: Vascular cognitive impairment (VCI) affects up to half of stroke survivors and predicts poor outcomes. Valid and reliable assessement for VCI is lacking, especially for the Chinese population. In 2005, the National Institute of Neurological Disorders and Stroke and Canadian Stroke Network (NINDS-CSN) Harmonisation workshop proposed a set of three neuropsychology protocols for VCI evaluation. This paper is to introduce the protocol design and to report the psychometric properties of the Chinese NINDS-CSN VCI protocols. METHODS: Fifty patients with mild stroke (mean National Institute of Health Stroke Scale 2.2 (SD=3.2)) and 50 controls were recruited. The NINDS-CSN VCI protocols were adapted into Chinese. We assessed protocols' (1) external validity, defined by how well the protocol summary scores differentiated patients from controls using receiver operating characteristics (ROC) curve analysis; (2) concurrent validity, by correlations with functional measures including Stroke Impact Scale memory score and Chinese Disability Assessment for Dementia; (3) internal consistency; and (4) ease of administration. RESULTS: All three protocols differentiated patients from controls (area under ROC for the three protocols between 0.77 to 0.79, p<0.001), and significantly correlated with the functional measures (Pearson r ranged from 0.37 to 0.51). A cut-off of 19/20 on MMSE identified only one-tenth of patients classified as impaired on the 5-min protocol. Cronbach's α across the four cognitive domains of the 60-min protocol was 0.78 for all subjects and 0.76 for stroke patients. CONCLUSIONS: The Chinese NINDS-CSN VCI protocols are valid and reliable for cognitive assessment in Chinese patients with mild stroke.

Transcranial Doppler ultrasound for screening cerebral small vessel disease: a community study.

BACKGROUND AND PURPOSE: We explored the association between pulsatility index (PI) as derived from transcranial Doppler ultrasound with various measures of small vessel disease in the community. METHODS: We performed transcranial Doppler and magnetic resonance imaging in 205 consecutive community-dwelling elderly subjects who were participants of the Shanghai Aging Study. We investigated the association between middle cerebral artery (MCA) PI with measures of white matter lesions (WML), lacunes, and microbleeds. RESULTS: Multiple logistic regression found that MCA PI was associated with severe WML (odds ratio, 1.33 per 0.1 increase in PI; 95% confidence interval, 1.04-1.70; P=0.02). At optimal MCA PI cut-off, the area under curve, positive predictive value, and negative predictive value were 0.70 (95% confidence interval, 0.60-0.80), 34.9%, and 85.6%, respectively, for detection of severe WML. No association was found between MCA PI and measures of lacunes or microbleeds. CONCLUSIONS: PI correlates with WML severity. With a high negative predictive value, the chance of having severe WML with a normal PI is low. Transcranial Doppler may guide selective magnetic resonance imaging scanning for the detection of WML in the community.

Predictors for cognitive decline in patients with confluent white matter hyperintensities.

BACKGROUND: Although patients harboring confluent white matter hyperintensities (WMH) are at high risk of cognitive decline, this risk varies among individuals. We investigated the predictors for cognitive decline in stroke patients with confluent WMH. METHODS: We followed up 100 stroke patients with confluent WMH who were participants of the VITAmins TO Prevent Stroke study for 2 years. We investigated the association between clinical features, apolipoprotein E status, imaging measures (infarcts, microbleeds, volumes of WMH, cortical gray matter [cGM], lateral ventricles, and hippocampi), and B vitamins with changes in cognitive measures (clinical dementia rating scale, Mini-Mental State Examination, Mattis dementia rating scale--initiation/perseveration subscale). We performed Pittsburgh compound B imaging among dementia converters. RESULTS: Multivariate regression analysis showed that increase in clinical dementia rating scale grade was associated with cGM atrophy, absence of hyperlipidemia, and lower diastolic blood pressure at baseline. cGM atrophy and absence of hyperlipidemia were also associated with deterioration in Mini-Mental State Examination and Mattis dementia rating scale--initiation/perseveration subscale scores. Pittsburgh compound B retention typical of Alzheimer's disease was found only in 10% of dementia converters. Incident stroke and B vitamins were not associated with cognitive decline. CONCLUSIONS: Among stroke patients with confluent WMH, cGM atrophy and absence of hyperlipidemia are important predictors for cognitive decline. Significant cognitive decline can occur in the absence of incident stroke or Alzheimer's pathology.