Late-onset multiple sclerosis: disability trajectories in relapsing-remitting patients of the Italian MS Registry

BACKGROUND

Generally infrequent, multiple sclerosis (MS) with late onset (LOMS) is characterized by an onset over the age of 50 and a mainly progressive course, while relapsing-remitting (RR) forms are less frequently observed and explored. This study aimed to characterize a large cohort of MS patients with RRMS at onset to assess the baseline factors related to the worst disability trajectories and explore the role of LOMS.

METHODS

The data were extracted from the Italian MS Register (IMSR). Disability trajectories, defined using at least two and up to twenty expanded disability status scale (EDSS) assessments annually performed, were implemented using group-based trajectory models (GBTMs) to identify different groups with the same trajectories over time. MS profiles were explored using multinomial logistic regression.

RESULTS

A total of 16,159 RR patients [1012 (6.26%) presented with LOMS] were analyzed. The GBTM identified four disability trajectories. The group with the most severe EDSS trend included 12.3% of the patients with a mean EDSS score > 4, which increased over time and exceeded 6 score. The group with medium severity EDSS trend comprised 21.9% of the patients and showed a change in EDSS > 3 scores over time. The largest group with 50.8% of patients reported a constant EDSS of 2 score. Finally, the benign group comprised 14.9% of the patients with a low and constant EDSS of 1 score over time. The probability of being in the worst groups increased if the patient was male; had LOMS or experienced brainstem, spinal, or supratentorial symptoms.

CONCLUSIONS

Four MS severity profiles among RRMS patients in the IMSR have been reported, with LOMS being associated with a rapid worsening of EDSS scores. These findings have important implications for recognizing and managing how older age, aging, and age-related factors interact with MS and its evolution.

Hierarchical structure in the activities of daily living and trajectories of disability prior to death in elderly Chinese individuals

Background

The global burden of disability continues to increase. Understanding the hierarchical structure of activities of daily living (ADL) and the trajectories of disability of elderly individuals is pivotal to developing early interventions.

Purpose

To determine the hierarchical structure of the ability of Chinese elderly individuals to perform ADL and further describe the trajectories of disability prior to death.

Methods

Longitudinal item response theory model (LIRT) was constructed for 28,345 elderly participants in the Chinese Longitudinal Healthy Longevity Survey, in which ADL were measured using the Katz scale from 1998 to 2018, until the participants’ death. Two difficulty parameters (κ₋partial and κ₋total) were used in the LIRT defining the thresholds for hierarchical structure in ADL (κ₋partial: no limitation to partial limitation, κ₋total: partial limitation to totally limited). Disability values estimated from the LIRT were fitted to a mixed-effects model to examine the manner in which the trajectories of disability varied with different subject characteristics.

Results

The findings confirmed the earliest loss in the capability to perform ADL (bathing(κ_-partial = − 1.396), toileting(κ_-partial = − 0.904)) at the level of partial limitation, with an overlap of partial and totally limited (total bathing, partial dressing, partial transferring, total dressing, partial feeding, partial continence), and finally a total loss of capability for toileting, feeding, transferring, and continence (κ_-total = 3.647). Disability trajectories varied with sex (β = 0.041, SE = 0.001), place of residence (β = 0.010, SE = 0.001), and marital status (β = 0.144, SE = 0.001). Females, individuals living in urban areas, and those who lived without a spouse had a poorer disability status.

Conclusion

The loss in the ability to perform ADL has a hierarchical structure. Subject characteristics affect trajectories of disability in the elderly Chinese population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02460-y.

Predictors for functional decline after an injurious fall: a population-based cohort study

Background

The functional consequences of injurious falls are well known. However, studies of the factors that can modify trajectories of disability after an injury from a fall are scarce.

Aims

We aimed to investigate whether sociodemographic and health-related factors may impact this association.

Methods

The study population consisted of 1426 community-dwelling older adults (≥ 60 years) from the SNAC-K cohort study in Stockholm, Sweden. Functional status over 12 years of follow-up was assessed using the number of limitations in basic and instrumental activities of daily living. Sex, cohabitation status, physical activity, and self-rated health were assessed at baseline. Injurious falls were defined as falls requiring healthcare and were assessed over 3 years starting at baseline. Data were analyzed using linear-mixed effects models.

Results

The fastest increase in the number of disabilities was observed in those who had endured an injurious fall and were living alone (β coefficient = 0.408; p < 0.001), been physically inactive (β coefficient = 0.587; p < 0.001), and had poor self-rated health (β coefficient = 0.514; p < 0.001). The negative impact of these factors was more pronounced among fallers compared to non-fallers.

Discussion

Living alone, being physically inactive, and having poor self-rated health magnifies the negative effect of an injurious fall on functional status. Among individuals who endure an injurious fall, the heterogeneity in long-term functional status is substantial, depending on the individuals’ characteristics and behaviors.

Conclusions

These findings emphasize the need for a person-centered approach in care provision and can guide secondary prevention within health care.

Electronic supplementary material

The online version of this article (10.1007/s40520-020-01747-1) contains supplementary material, which is available to authorized users.

Definitions of primary-progressive multiple sclerosis trajectories by rate of clinical disability progression

BACKGROUND

Patients with primary progressive multiple sclerosis (PPMS) vary in the rate of disability progression.

OBJECTIVE

To classify clinical disability trajectories by rate of disability progression and evaluate predictive variables in PPMS patients.

METHODS

We analyzed the cumulative incidence of progression to disability and in accordance defined clinical PPMS disability trajectories. Correlation was performed with age, gender and disability at first presentation. Estimated onset was calculated and validated by the mathematical slope of disability progression.

RESULTS

The cohort included 304 PPMS patients, 146 (48%) were females, the mean age at first visit was 41.1 years, and the median follow up was 18.9 years. Median time to reach moderate and severe disability was 4.5 years (95%CI 3.8-5.2) and 12.6 years (95%CI 10.1-14.2), respectively. Extremely fast patients (3.3%) progressed to severe disability within 2-years, while very slow patients (4.7%) did not progress to moderate disability even 20 years after first presentation. Age and gender were not associated with progression. Moderate disability at first visit was associated with faster progression to severe disability. Mean estimated range of disease onset was between 4.3 to 9.9 years prior to first presentation.

CONCLUSIONS

Majority of PPMS patients progressed to moderate disability within 5-years and to severe disability within 15-years from first presentation. Clinical disability progression trajectories can help treatment-related decisions.

Trajectories of Late-Life Disability Vary by the Condition Leading to Death

BACKGROUND

Previous research suggested that there might be distinct patterns of functional decline in the last years of life depending on the condition leading to death, but the validity of these results and hence the explanatory value of the condition leading to death for late-life disability are uncertain.

METHODS

A total of 636 decedents from a cohort of 754 community-living persons, 70+ years of age (Yale PEP Study) provided 33 700 monthly observations of self-/proxy-reported disability during the last 5 years of life. Nonlinear trajectories and short-term fluctuations of late-life disability by condition leading to death (cancer, organ failure, frailty, severe dementia, sudden death, other) were estimated with flexible mixed spline regression models.

RESULTS

Disability trajectories at the end of life varied distinctively by the condition leading to death. Estimated disability trajectories among cancer deaths increased gradually up until about 6 months before death, after which a steep terminal decline set in. Among those with organ failure, frailty, and dementia, in contrast, disability was higher, increased more gradually, and there was no clear-cut terminal phase. Adding the condition leading to death to other known risk factors increased the amount of explained between-person variation in late-life disability from R2 = 0.35 to 0.49. Short-term fluctuations in disability were not specific for decedents with organ failure.

CONCLUSIONS

The condition leading to death is an important determinant of trajectories of late-life disability. These trajectories follow distinct patterns partially resembling a previously outlined theoretical typology.

Trajectories of Work Disability and Economic Insecurity Approaching Retirement

OBJECTIVES

In this article, we examine the connection between trajectories of work disability and economic precarity in late midlife. We conceptualize work disability as a possible mechanism linking early and later life economic disadvantage.

METHODS

We model trajectories of work disability characterized by timing and stability for a cohort of Baby Boomers (22-32 in 1981) using 32 years of data from the Panel Study of Income Dynamics and latent class analysis. Measures of childhood disadvantage are included as predictors of work disability trajectories, which are subsequently included in logistic regression models predicting four economic outcomes (poverty, asset poverty, home ownership, and pension ownership) at ages 54-64.

RESULTS

Childhood disadvantage selected individuals into five distinct classes of work disability that differed in timing and stability. All of the disability trajectories were associated with an increased risk of economic insecurity in late midlife compared to the never work disabled.

DISCUSSION

This study contributes to the aging literature through its incorporation of the early life origins of pathways of disability and their links to economic outcomes approaching retirement. Findings suggest work disability is anchored in early life disadvantage and is associated with economic insecurity later in life.