Frailty – identifying the causes
The development of medical provision and healthcare accessibility has all but wiped out the incidence of communicable diseases and infections, leading to novel health issues for the ageing population. Men and women in the UK can now expect to 79 and 82 respectively, up from 50 and 54 years in 1919. Along with this conundrum, within 50 years, an additional 9 million elderly people will be alive in the United Kingdom, posing serious issues for social and healthcare sectors.
Falls are common for individuals over the age of 65, along with a significant comorbidity of hip fracture. This has a big impact on the quality of life and again places considerable strains on health and social care. It’s estimated that the yearly spending on falls in elderly individuals is as much as £4 billion, and hospitalisation for falls and fall related injuries often leads to a loss of independence and further disability. The term frailty is used quite colloquially to describe older people who may look physically deteriorated, weak and unstable. But in reality, is a multi-faceted syndrome which often manifests in a variety of ways such as;
Indeed, frailty – rather than being treated as a disease – is a ‘catch all’ term to describe manifestations of weakness and lack of resilience in elderly individuals and has many psychological and social contributors. It’s estimated that in 70-80% of individuals displaying symptoms of somatic, physical frailty, these individuals also had moderate to severe symptoms of depression and loneliness, something which is linked to isolation, lack of support and lack of family members. Indeed, we often think typically of frail individuals as those who may not have family or friends to look after them, and typically may reduce their physical activity due to isolation and withdrawal. Even more impetus is placed in addressing frailty in those with other conditions such as Parkinson’s, dementia and alzheimer’s, although the manifestations of frailty in these cases is typically more severe and is second to the development of their primary disease.
It Is believed that frailty is typically more disabling in elderly women, often due to the historical role of women as sedentary care givers in the family, which may have influenced this populations attitudes to physical activity, health and exercise. Indeed, as women tend to live longer than men on average, potentially they are exposed to greater temporal aspects of ageing such as muscle loss, changes in hormones, nutritional inadequacies and low physical activity, all of which confound and create a more severe degree of frailty. Indeed, individuals who experience a fall are likely to fall again in the future, and hip, arm and leg fracture in this population are normally significant enough to impede gait for the rest of their life, requiring further social care and assistance.
Aside from the social and psychological predictors of frailty, changes in hormones around middle age in men and women often provoke early changes in muscle mass, recruitment and homeostatic control (the maintenance of normal body conditions). When the sex hormones (oestrogen and testosterone) decline around middle age, different factors influencing inflammation called cytokines become more active and have a greater effect on the body. One of the theories surrounding the development of frailty is the pro-inflammatory hypothesis, which posits that cell signalling and changes in hormones in both sexes causes muscle degradation and adversely influences overall health. Indeed, those who experience frailty often have other inflammatory health conditions such as obesity, type 2 diabetes and cancers, which all confound and cause adverse changes around the body affecting organs, the brain and eventually the recruitment of muscles – a big factor in the gait of elderly individuals.
It is often thought that individuals who typically perform more physical activity and exercise throughout their life experience a lesser degree of frailty, mainly due to the accumulation of functional muscle mass which happens in response to long term exercise. When muscle breakdown (sarcopenia) occurs over time, this happens to a lesser degree in those with good nutrition and activity levels due to the improvement in retention of muscle fibres. However, the benefits of physical activity must be weighed against the risks in these populations, as inappropriate activity may provoke a fall in elderly individuals and may risk injury.
Polypharmacy (the use of multiple drugs for health conditions) is a valid concern in elderly populations, often for the treatment of different medical conditions. However, it is of concern to clinicians to evaluate the use of drugs for conditions which are not life threatening, as a combination of pharmaceutical compounds may produce adverse side effects. In elderly individuals, the effects of dizziness, exhaustion and double vision all affect balance (proprioception) which can predispose these individuals to falls and subsequent injury. Coupled with the development of worse balance throughout the lifespan, polypharmacy must be managed on an individual basis and with the notion, “the least drugs possible for the least time possible, where possible”.
Changes in muscle recruitment over time due to loss of muscle, arthritis, changes is balance and resistance in joints, tendons and ligaments can affect the gait (walking style) in elderly individuals. Often, clinicians test the walking capacity of elderly patients by asking them to get up from a chair and walk a short distance, which is timed and compared against normative data. It is thought that degradation in different parts of the brain and vestibular apparatus (the balance centre in the ears) changes the perception and ability of the individual to change to uneven surfaces and environments. When the gait of elderly individuals is studied, it is found that there is a wide variation in the stride length, along with the variability in the stance during walking, suggesting that overload occurs to different sensory areas of the brain. Indeed, when stressed with cognitive tasks, elderly individuals often experience a worsening gait as sensory information overloads the areas of the brain which control fine motor output. Thus, a damaged balance system and potential degradation of sensory processing can cause a fall due to a loss of balance in elderly individuals, predisposing them to further injury. Finally, the loss of muscle mass due to sedentary lifestyles also changes the recruitment of muscles throughout the walking cycle, often towards an over recruitment of the hips and quadricep muscles. Thus, when a response is required during walking, an overload of output is sent to the muscles and fine motor control is lost, causing an ‘over reaction’ of the muscle to the stimulus. This is often what causes falls in frail individuals, as the sudden jerk or movement from their muscle output is enough to cause severe balance disturbance, and they often fall.
the classification of frail elderly people is often completed using criteria given by Fried et al (2001) or Rockwood et al (2005). The latter is a clinical ‘frail scale’ which involves visual determination of the degree of frailty, which can often be well predicted by looking at individuals. Thus, clinical decisions are made based on the shape, sway and posture of individual when walking, resting, and through a detailed clinical history.