Vincentius J.A. Verlinden

Gait patterns in a community-dwelling population aged 50 years and older

Poor gait is an important risk factor for falls and associated with higher morbidity and mortality. It is well established that older age is associated with worse gait, but it remains unclear at what age this association is first seen. Moreover, previous studies focused mainly on normal walking, but gait also encompasses turning and tandem walking. In a large study of community-dwelling middle-aged and elderly persons we investigated the association of age with gait, focusing on normal walking, turning and tandem walking. In 1500 persons aged 50 years and over, we measured gait using an electronic walkway. Participants performed normal walks, turning and a tandem walk. With principal components analysis of 30 variables we summarized gait into five known gait factors: Rhythm, Variability, Phases, Pace and Base of Support; and uncovered two novel gait factors: Tandem and Turning. The strongest associations with age were found for Variability (difference in Z-score -0.29 per 10 years increase (95% confidence interval: -0.34; -0.24)), Phases (-0.31 per 10 years (-0.36; -0.27)) and Tandem (-0.25 per 10 years (-0.30; -0.20)). Additionally, these factors already showed association with the youngest age groups, from 55 to 60 years of age and older. Our study shows that Variability, Phases and Tandem have the strongest association with age and are the earliest to demonstrate a poorer gait pattern with higher age. Future research should further investigate how these gait factors relate with gait-related diseases in their earliest stages.

Cognition and gait show a distinct pattern of association in the general population

With brain aging, cognition and gait deteriorate in several domains. However, the interrelationship between cognitive and gait domains remains unclear. We investigated the independent associations between cognitive and gait domains in a community‐dwelling population.

Risk of Frailty in Elderly With COPD: A Population-Based Study

BACKGROUND Despite frailty being an important geriatric syndrome, its prevalence and associated mortality risk in older patients with chronic obstructive pulmonary disease (COPD) are unknown. METHODS We examined the relationship between COPD confirmed by spirometry, COPD severity, and frailty defined by the Fried criteria within 2,142 participants (aged 74.7 ± 5.6 years) of the Rotterdam Study, a prospective population-based cohort study. RESULTS The frailty prevalence was significantly higher (p < .001) in participants with COPD (10.2%, 95% CI: 7.6%-13.5%) compared with participants without COPD (3.4%, 95% CI: 2.6%-4.4%). Adjusted for age, sex, smoking, corticosteroids, and other confounders, participants with COPD had a more than twofold increased prevalence of frailty (odds ratio 2.2, 95% CI: 1.34-3.54, p = .002). The prevalence was highest when severe airflow limitation, dyspnea, and frequent exacerbations were present. Participants with mild airflow limitation were more frequently prefrail. COPD elderly who were frail had significant worse survival. CONCLUSIONS This population-based cohort study in elderly demonstrates that COPD is associated with frailty even after adjusting for shared risk factors. Our findings suggest that frailty-in addition to COPD severity and comorbidities-identifies those COPD participants at high risk of mortality.

Trajectories of prediagnostic functioning in Parkinson’s disease

See Breen and Lang (doi:10.1093/aww321) for a scientific commentary on this article. At the time of clinical diagnosis, patients with Parkinson’s disease already have a wide range of motor and non-motor features that affect their daily functioning. However, the temporal sequence of occurrence of these features remains largely unknown. We studied trajectories of daily functioning and motor and non-motor features in the 23 years preceding Parkinson’s disease diagnosis by performing a nested case-control study within the prospective Rotterdam study. Between 1990 and 2013, we repeatedly performed standardized assessments of daily functioning (Stanford Health Assessment Questionnaire, Lawton Instrumental Activities of Daily Living Scale), potential prediagnostic motor (hypo- and bradykinesia, tremor, rigidity, postural imbalance, postural abnormalities) and non-motor features of Parkinson’s disease, including cognition (Mini-Mental State Examination, Stroop Test, Letter-Digit-Substitution Test, Word Fluency Test), mood (Center for Epidemiological Studies-Depression Scale, Hamilton Anxiety and Depression Scale), and autonomic function (blood pressure, laxative use). In addition, the cohort was followed-up for the onset of clinical Parkinson’s disease using several overlapping modalities, including repeated in-person examinations, as well as complete access to medical records and specialist letters of study participants. During follow-up, 109 individuals were diagnosed with Parkinson’s disease, and each case was matched to 10 controls based on age and sex (total n = 1199). Subsequently, we compared prediagnostic trajectories of daily functioning and other features between Parkinson’s disease cases and controls. From 7 years before diagnosis onwards, prediagnostic Parkinson’s disease cases more commonly had problems in instrumental activities of daily functioning, and more frequently showed signs of movement poverty and slowness, tremor and subtle cognitive deficits. In the past 5 years, Parkinson’s disease cases developed additional motor features (postural imbalance, rigidity, and postural abnormalities) and increasingly reported problems in basic daily activities. Parkinson’s disease cases also increasingly reported anxiety symptoms, depressive symptoms, and use of laxatives throughout study follow-up, although differences with controls only became statistically significant in the last years before diagnosis. In conclusion, in patients with prediagnostic Parkinson’s disease, impairments in instrumental daily activities, which require both motor and non-motor skills, pre-date difficulties in more physically oriented daily activities.

Trajectories of decline in cognition and daily functioning in preclinical dementia

Although preclinical dementia is characterized by decline in cognition and daily functioning, little is known on their temporal sequence. We investigated trajectories of cognition and daily functioning in preclinical dementia, during 18 years of follow‐up.

Gait patterns in COPD: the Rotterdam Study

Gait disturbances in patients with chronic obstructive pulmonary disease (COPD) may lead to disability and falls. As studies assessing gait kinematics in COPD are sparse, we investigated associations of COPD with various gait domains and explored a potential link with falling. Gait was measured within the prospective, population-based Rotterdam Study (age ≥55 years) using an electronic walkway and summarised into seven gait domains: Rhythm, Variability, Phases, Pace, Tandem, Turning and Base of Support. Rhythm is a temporal gait aspect that includes cadence and reflects how quickly steps are taken. Persons with COPD (n=196) exhibited worse Rhythm (−0.21 sd, 95% CI −0.36– −0.06 sd) compared with persons with normal lung function (n=898), independent of age, sex, height, education, smoking or analgesic use, especially when dyspnoea and severe airflow limitation or frequent exacerbations (Global Initiative for Chronic Obstructive Lung Disease group D: −0.83 sd, 95% CI −1.25– −0.41 sd) were present. A lower forced expiratory volume in 1 s was associated with worse Rhythm and Pace, including lower cadence and gait velocity, respectively. Importantly, fallers with COPD had significantly worse Rhythm than nonfallers with COPD. This study demonstrates that persons with COPD exhibit worse Rhythm, especially fallers with COPD. The degree of Rhythm deterioration was associated with the degree of airflow limitation, symptoms and frequency of exacerbations. This study comprehensively investigates, in a large, population-based cohort, the gait pattern in COPD http://ow.ly/HQbc3

Structural and Microstructural Brain Changes Predict Impairment in Daily Functioning

BACKGROUND Brain changes on magnetic resonance imaging (MRI) reflect accumulating pathology and have clinically disabling consequences, such as dementia. However, little is known on the relation of these MRI markers with daily functioning in nondemented individuals. We investigated whether structural and microstructural brain changes are associated with impairment in activities of daily living in a community-dwelling population. METHODS Between 2005 and 2009, 2025 stroke-free nondemented participants (aged 59.9 years) from the population-based Rotterdam Study underwent brain MRI, yielding global MRI markers, focal MRI markers, and microstructural MRI markers. We used the Stanford Health Assessment Questionnaire to assess basic activities of daily living, and the Instrumental Activities of Daily Living Scale to assess instrumental activities of daily living. Follow-up on activities of daily living was obtained between 2008 and 2013 (mean follow-up 5.7 years). We used linear regression to analyze continuous scores of daily living and logistic regression for incident impairment. RESULTS Eighty-two participants became impaired in basic and 33 in instrumental activities of daily living. Smaller brain and hippocampal volume and higher diffusivity were associated with larger change in activities of daily living. Smaller brain volume (odds ratio [OR] 4.05 per SD; 95% confidence interval [CI], 1.81-9.02), larger white matter lesion volume (OR 1.33/SD; 95% CI 1.02-1.72) and higher mean (OR 1.55/SD; 95% CI, 1.11-2.15), axial (OR 1.49/SD; 95% CI, 1.08-2.07), and radial diffusivity (OR 1.51/SD; 95% CI, 1.09-2.10) were associated with higher risk of impairment in basic activities of daily living. CONCLUSIONS In community-dwelling individuals, brain changes are associated with deterioration and incident impairment in daily functioning.

Tract-specific white matter microstructure and gait in humans.

Gait is a complex sequence of movements, requiring cooperation of many brain areas, such as the motor cortex, somatosensory cortex, and cerebellum. However, it is unclear which connecting white matter tracts are essential for communication across brain areas to facilitate proper gait. Using diffusion tensor imaging, we investigated associations of microstructural organization in 14 brain white matter tracts with gait, among 2330 dementia- and stroke-free community-dwelling individuals. Gait was assessed by electronic walkway and summarized into Global Gait, and 7 gait domains. Higher white matter microstructure associated with higher Global Gait, Phases, Variability, Pace, and Turning. Microstructure in thalamic radiations, followed by association tracts and the forceps major, associated most strongly with gait. Hence, in community-dwelling individuals, higher white matter microstructure associated with better gait, including larger strides, more single support, less stride-to-stride variability, and less turning steps. Our findings suggest that intact thalamocortical communication, cortex-to-cortex communication, and interhemispheric visuospatial integration are most essential in human gait.

Gait shows a sex-specific pattern of associations with daily functioning in a community-dwelling population of older people

BACKGROUND Gait is increasingly considered an important indicator of health. Yet, little is known on the relation of gait with established health indicators, e.g. daily functioning. Although gait differs by sex, it is unknown whether different gait domains provide different health indicators in men or women. We investigated how gait associates with basic and instrumental activities of daily living (BADL and IADL) in community-dwelling persons. METHODS In 2500 participants of the population-based Rotterdam Study (aged ≥ 50 yrs), gait was assessed by electronic walkway and summarized into seven independent gait domains: Pace, Rhythm, Phases, Tandem, Turning, Variability, Base of Support, which were averaged into Global Gait. We assessed BADL with the disability index of the Stanford Health Assessment Questionnaire and IADL with the Instrumental Activities of Daily Living scale. BADL and IADL were analyzed as continuous scores, and dichotomised: with impairment defined as moderate to very severe disability. RESULTS In men, Global Gait, Pace, and Rhythm associated with BADL in linear analyses. In contrast, all domains except Base of Support associated with BADL or IADL in women. Associations of Global Gait and Phases with BADL were significantly stronger in women (p-interaction < 0.05). Similarly, associations of Global Gait, Rhythm, and Phases with IADL were stronger in women (p-interaction < 0.05). For dichotomised analyses, higher Global Gait, Pace, and Rhythm associated with less BADL-impairment in men, while Global Gait associated with less BADL and IADL-impairment in women. CONCLUSIONS In men, Pace and Rhythm may suffice as health indicators, while women may require comprehensive gait assessment to better estimate their health status.

Mid- to Late-Life Trajectories of Blood Pressure and the Risk of Stroke The Rotterdam Study

Hypertension is a major modifiable risk factor for stroke. Associations of blood pressure with incident stroke are mostly based on single or average blood pressure levels. However, this approach does not take into account long-term trajectories of blood pressure, which can vary considerably in the elderly. Within the population-based Rotterdam Study, we examined trajectories of systolic blood pressure in 6745 participants (60.0% women) over an age-range from 55 to 106 years and jointly modeled their risk of stroke and competing causes of death using joint latent class mixed modeling. Four trajectories were identified. Class 1 was characterized by blood pressure increasing gradually from on average 120 to 160 mm Hg over 5 decades (n=4938). Compared with this class, class 2, characterized by a similar midlife blood pressure, but a steep increase (n=822, increasing from 120 to 200 mm Hg), and class 4, characterized by a high midlife blood pressure (n=115; average 160 mm Hg) and had a higher risk of stroke and death. Class 3, characterized by a moderate midlife blood pressure (n=870; average 140 mm Hg), had a similar risk of death as class 1, but the highest risk of stroke. Assessing trajectories of blood pressure provides a more nuanced understanding of the associations between blood pressure, stroke, and mortality. In particular, high blood pressure and rapidly increasing blood pressure patterns are associated with a high risk of stroke and death, whereas moderately high blood pressure is only related to an increased risk of stroke. Future studies should explore the potential pathogenic significance of these patterns.