Respiratory function and cognitive profile in amyotrophic lateral sclerosis.

BACKGROUND AND PURPOSE: Amyotrophic lateral sclerosis (ALS) is increasingly recognized as a multisystem disorder with 30%-50% of patients exhibiting cognitive impairment. The pathophysiological mechanisms of cognitive dysfunction are probably multifactorial although hypoventilation secondary to respiratory dysfunction may contribute to cognitive decline. The current study aimed to identify the relationship between respiratory function in ALS patients and the presence and degree of cognitive impairment. METHODS: Amyotrophic lateral sclerosis patients were prospectively recruited from a multidisciplinary ALS clinic. Baseline clinical assessments including respiratory function as assessed by spirometry were recorded with forced vital capacity (FVC) ≤ 75% considered to be reduced respiratory function. Cognitive testing was performed utilizing the Addenbrooke's Cognitive Examination (ACE) and the Mini-Mental State Examination (MMSE). RESULTS: From a cohort of 100 ALS patients, 48% were categorized as having impaired respiratory function (FVC = 58.24% ± 2.15%) whilst 52% had normal function (88.65% ± 1.27%). Compared to the group with normal respiratory function (ACE 90.68 ± 0.89, MMSE 28.22 ± 0.21), patients with respiratory dysfunction had significantly reduced cognitive function (ACE 86.83 ± 1.5, P = 0.025; MMSE 26.29 ± 0.45, P = 0.029). Furthermore, subscores demonstrated significant differences between the groups with respect to domains in memory (P = 0.003) and attention (P = 0.05) with a trend observed in fluency (P = 0.082). There was a significant correlation between patient baseline FVC and ACE scores as well as between FVC and memory and fluency subscores (P < 0.01). CONCLUSION: Amyotrophic lateral sclerosis patients with respiratory compromise were more likely to develop reduced cognitive function. In addition to improving physical function, it remains plausible that non-invasive ventilation may alter the progression of cognitive impairment in ALS patients and potentially improve overall quality of life and carer burden.

Apathy is associated with poor prognosis in amyotrophic lateral sclerosis.

BACKGROUND AND PURPOSE: Apathy is the most commonly reported behavioural change in amyotrophic lateral sclerosis (ALS). However, the degree to which it affects prognosis and overlaps with depression in this population is unknown. The present study examined the relationship between level of apathy, mortality and survival time and whether apathy was linked to specific symptom clusters of depression. METHODS: A cohort of 76 consecutive ALS patients attending specialized multidisciplinary clinics were classified according to level of apathy. The effects of clinical factors and apathy on survival time were analysed using univariate and multivariate methods. RESULTS: The majority of patients with moderate to severe apathy died during the study (P = 0.003) and had a median survival time of 21.7 months, considerably shorter than patients with mild apathy (46.9 months) and no apathy (51.9 months) (P = 0.0001). Apathy remained a significant predictor of survival even after controlling for clinical factors and symptom duration at the time of study entry (hazard ratio 3.8, 95% confidence interval 1.9-7.5, P = 0.0001). Depression with demoralization was not associated with level of apathy (P = 0.172) whereas depression with anhedonia was more common in patients with apathy than in those without apathy (P = 0.006). CONCLUSIONS: The presence of severe apathy is an independent, negative prognostic factor in ALS.

Motor function and behaviour across the ALS-FTD spectrum.

BACKGROUND: Behavioural/functional disturbances, characteristic of frontotemporal dementia (FTD), are also a feature of amyotrophic lateral sclerosis (ALS) and patients with combined ALS and FTD (FTD-ALS). AIM OF THE STUDY: To investigate the progression of behavioural disturbances in ALS and FTD using the FTD functional rating scale (FTDFRS). METHODS: Patients with ALS, FTD-ALS and FTD were recruited from specialist clinics. Baseline assessments included the FTDFRS and the ALS functional rating scale-revised (ALSFRS-R). Baseline assessments were included, as were longitudinal assessments in a proportion of patients. RESULTS: In total, 21 ALS, 12 FTD-ALS and 14 behavioural variant FTD (bvFTD) patients were included in the study. Moderate or severe behavioural disturbance was common in patients with ALS at baseline (47.6%), although less frequent than in bvFTD patients; patients with FTD-ALS displayed intermediate impairment. The ALSFRS-R showed the opposite pattern and did not correlate with the FTDFRS. During the follow-up period, significant (P < 0.05) behavioural deterioration was demonstrated in patients with bvFTD and FTD-ALS, with a trend for decline in patients with ALS (P = 0.06). CONCLUSION: Motor disturbance is the primary marker of disease severity in ALS, but behavioural and functional impairment are common, and may decline independently of motor function. As such, the FTDFRS may provide valuable information in the assessment and monitoring of ALS.

Apathy and its impact on patient outcome in amyotrophic lateral sclerosis.

Apathy is one of the most common behavioural symptoms of amyotrophic lateral sclerosis (ALS), yet there are few studies that have investigated the relationship between apathy and quality of life (QOL) as they are experienced by the patient. A cohort of 60 ALS patients were evaluated using the Apathy Evaluation Scale which measured cognitive, behavioural, emotional and non-specific symptoms of apathy combined with the Personal Wellbeing Index, a multidimensional measure of QOL. The relationship between patient-rated apathy and QOL scores, controlling for potential clinical and psychological confounders were analysed using univariate and multivariate methods. Apathy was identified in 30% of ALS patients. Patients with apathy reported higher levels of depression (p = 0.0001). Compared to non-apathetic patients, patients with apathy had lower overall QOL (p = 0.001), most pronounced in the domains related to achievements in life (p = 0.001) and community-connectedness (p = 0.0001). Of the cognitive, behavioural, emotional and non-specific manifestations of apathy, only the emotional symptoms explained a significant amount of variance in achievements in life (p = 0.003) and community-connectedness (p = 0.001). As such, emotional manifestations of apathy may underlie worse QOL in ALS patients presenting with behavioural impairment. Patient-reported outcomes, particularly those assessing psychosocial functioning may be important for demonstrating the efficacy of interventions designed to improve QOL in ALS patients with behavioural impairment.

Cognition and eating behavior in amyotrophic lateral sclerosis: effect on survival.

It is increasingly recognized that metabolic factors influenced by eating behavior, may affect disease progression in neurodegeneration. In frontotemporal dementia (FTD), which shares a significant overlap with Amyotrophic lateral sclerosis (ALS), patients are well known to develop changes in eating behavior. Whether patients with pure ALS and those with cognitive and behavioral changes associated with ALS also develop similar changes is not known. The current study aimed to examine caloric intake, eating behavioral changes, body mass index, and using cox regression analyses survival across the spectrum of 118 ALS-FTD patients (29 pure ALS, 12 ALS-plus and 21 ALS-FTD, 56 behavioral variant FTD), compared with 25 control subjects. The current study found contrary to previous assumptions eating changes are not restricted to FTD, but a spectrum of eating behavioral changes occur in ALS, present in those with pure ALS and worsening as patients develop cognitive changes. ALS patients with cognitive impairment exhibited changes in food preference, with caloric intake and BMI increasing with the development of cognitive/behavioral changes. Both pure ALS and those with cognitive impairment demonstrated increased saturated fat intake. Survival analyses over the mean patient follow-up period of 6.9 years indicated that increasing eating behavioral changes were associated with an improved survival (threefold decrease risk of dying). Changes in eating behavior and metabolism occur in ALS in association with increasing cognitive impairment, perhaps exerting a protective survival influence. These changes provide insights into the common neural networks controlling eating and metabolism in FTD and ALS and provide potential targets to modify disease prognosis and progression.

Body mass index delineates ALS from FTD: implications for metabolic health.

Weight loss and catabolic changes are increasingly recognized as factors that influence outcomes in patients with amyotrophic lateral sclerosis (ALS). An association between disease progression and low BMI has been reported in ALS; however, it remains unknown whether low BMI occurs across all forms of ALS and whether BMI changes with the development of cognitive impairment across the spectrum between ALS and frontotemporal dementia (FTD). One hundred and three ALS patients (56 limb predominant, 18 bulbar predominant, 13 ALS plus, 16 ALSFTD) were recruited and compared to 19 behavioral variant FTD (bvFTD) patients and a group of age-matched healthy controls. BMI was measured at the initial clinical visit. Patients were characterized as underweight, normal, overweight or obese, based on the current World Health Organization (WHO) guidelines. Limb and bulbar ALS patients had significantly lower BMI than ALS plus, ALSFTD, and bvFTD patient groups. When BMI was categorized using WHO guidelines the majority of the limb and bulbar ALS patients were either underweight or normal weight, whilst the majority of the ALS plus, ALSFTD and bvFTD patients were either overweight or obese. On follow-up BMI assessment the limb and bulbar groups tended to decline whilst ALS plus, ALSFTD and bvFTD groups remained stable or increased. BMI is significantly higher in ALS individuals with cognitive deficits. The present findings have prognostic implications for disease progression and may help delineate the metabolic profile across the ALSFTD spectrum.