Relation between psychological variables of caregivers and respiratory function in patients with Amyotrophic Lateral Sclerosis

Background: Amyotrophic Lateral Sclerosis (ALS) is a rare fatal neurodegenerative disorder with no curative treatment, characterized by degeneration of motor neurons involving a progressive impairment of motor and respiratory functions. Most patients die of ventilatory failure. The role of caregiver, usually a relative who lives with the patient and provides him “with the most care and assistance”, is very important for ALS patients. It has a great influence among patient’s quality of life, as well as the quality of care. Clinical evidences indicate that carers should be involved in care management, in order to help the patient when at home. Home influence of caregiver among patient’s care is huge. At date, however, no study at our knowledge investigated how psychological issues of caregivers would influence respiratory variables of ALS patients. Design: We conducted a repeated measures design study, investigating respiratory issues (FVC and PCF) and the perception of Social Support (McGill Social Support Subscale, MG-SS) of ALS patients. Their caregivers filled questionnaires about Anxiety (State-Trait Anxiety Inventory, STAI), Depression (Beck Depression Inventory, BDI) and Care Burden (Zarit Burden Inventory, ZBI). Objective: to investigate the impact of social support and psychological well-being of caregivers among ALS respiratory variables.  Method: Our study was conducted at the NEMO - NEuroMuscular Omnicentre in Milan, a clinical service specialized in treatment and management of neuromuscular disorders, with a multidisciplinary care. We included 40 ALS patients, together with their caregivers and we assessed them twice: baseline (T1) and follow-up (T2) assessments, four months later. We conducted Pearson’s correlations between T1 variables and linear regressions in order to evaluate if psychological variables at T1 influence respiratory parameters at T2. Results: In a cross-sectional analysis of T1 data, FVC and PCF were positively related to patient’s perception of Social Support (MG-SS) and negatively related to caregiver’s STAI, BDI and ZBI. Patient’s MG-SS, as well as caregiver’s depression (BDI) at T1 were significantly able to positively predict patient’s FVC and PCF at T2. Caregiver’s anxiety (STAI) and burden (ZBI) failed to statistically predict respiratory values, but showed high levels of correlation. Discussion: We argue that a better psychological condition of caregiver, especially when perceived by the patient, can really improve respiratory issues. We suggest that there could be two explanations: If caregiver feels psychologically better, patient’s quality of life improves and a condition of greater well-being and relax could increase ventilatory capacity; Care management could be carried out more easily by caregivers that could pay more attentions on patient’s respiratory needs and spend more time in assistance. Conclusions: Our data indicate that patients’ perception of social support, as well as caregivers’ psychological well-being seem to influence respiratory issues. According to our results, it is very important to provide assistance not only patients, but also their relatives, in order to improve families’ quality of life, together with patient’s ventilatory functions.