Multimorbidity in older adults with intellectual disabilities

Highlights

• Multimorbidity is prevalent in 80% of the older adults with ID.

• Multimorbidity is associated with age and severity of intellectual disability.

• Having ≥4 chronic conditions was associated with Down syndrome.

Abstract

Multimorbidity may be related to the supposed early aging of people with intellectual disabilities (ID). This group may suffer more often from multimorbidity, because of ID-related physical health conditions, unhealthy lifestyle and metabolic effects of antipsychotic drug use. Multimorbidity has been defined as two or more chronic conditions. Data on chronic conditions have been collected through physical assessment, questionnaires, and medical files. Prevalence, associated factors and clusters of multimorbidity have been studied in 1047 older adults (≥50 years) with ID. Multimorbidity was prevalent in 79.8% and associated with age and severe/profound ID. Four or more conditions were prevalent in 46.8% and associated with age, severe/profound ID and Down syndrome. Factor analyses did not reveal a model for disease-clusters with good fit. Multimorbidity is highly prevalent in older adults with ID. Multimorbidity should receive more attention in research and clinical practice for targeted pro-active prevention and treatment.

Introduction

It has long been a common understanding, that people with intellectual disabilities (ID) ‘are old from the age of 50 years onwards’ (Perkins and Moran, 2010, Roth et al., 1996). Nevertheless, apart from people with Down syndrome (Roth et al., 1996), premature aging has never been scientifically confirmed for this group. Geriatric frailty occurs early in the population with ID (Evenhuis, Hermans, Hilgenkamp, Bastiaanse, & Echteld, 2012) and is considered to be a risk factor for subsequent deterioration of health and independence (Fried et al., 2001), occurs early in the population with ID. Their mean frailty index scores at age 50–59 years are comparable to those in the general population aged 70–79 years (Schoufour, Mitnitski, Rockwood, Evenhuis, & Echteld, 2013). This early occurrence of frailty might be an explanation for the perceived early aging.

Frailty might be partly caused by multimorbidity, which refers to the occurrence of two or more chronic conditions. The prevalence of multimorbidity has been extensively studied in older people with normal intelligence (Glynn et al., 2011, Schram et al., 2008, Van Oostrom et al., 2011). The results of these studies imply that prevalence increases with age and is related to female gender, lower education and low social-economic status (Marengoni et al., 2008, Salisbury et al., 2011, Tucker-Seeley et al., 2011, Uijen and van de Lisdonk, 2008). Despite the numerous studies, treatment options are still vague. Physicians seem to treat each disease separately and show little attention for the synergy between different diseases (Bower et al., 2012), whereas lack of good treatment causes ongoing functional decline, impaired quality of life and early death (Drewes et al., 2011, Fortin et al., 2006, Hunger et al., 2011, Landi et al., 2010).

People with ID seem to have an increased risk of chronic multimorbidity (McCarron et al., 2013) for several reasons. Multimorbidity may start at a young age, with conditions related to brain damage, impaired brain development, and etiologic syndromes. For example, people with cerebral palsy often have motor impairment, epilepsy and other neurologic problems (Arvio & Sillanpaa, 2003). What is more, risks to develop age-related conditions may be different because of superpositioning on childhood conditions and other unfavorable factors (De Winter, Bastiaanse, Hilgenkamp, Evenhuis, & Echteld, 2012). For instance, an increased risk of cardiovascular risk factors is found both in young and older adults with ID (De Winter et al., 2012, Emerson, 2005, Haveman et al., 2011). This may not only be attributable to an unhealthy lifestyle, but also to metabolic effects of antipsychotic drug use (De Kuijper et al., 2013) and fragmented sleep–wake rhythms (Maaskant, van de Wouw, van Wijck, Evenhuis, & Echteld, 2013).

Nevertheless, medical care for this group is primarily reactive, i.e. if complaints or observed symptoms are brought to the attention of the physician (Lennox, Diggens, & Ugoni, 1997). Multimorbidity and frail unhealthy life-years may be delayed by treating conditions that are to be expected during early and later adulthood, as well as anticipating healthcare, aimed at prevention and pro-active diagnosis. Consequently, healthcare costs will decrease because of less dependency caused by additional diseases.

To improve healthcare for people with ID, more knowledge on multimorbidity is necessary (McCarron et al., 2013). Therefore, we studied the prevalence and associated factors of chronic multimorbidity in the broad client population, aged 50 years and over, of Dutch intellectual disability service providers. We have also studied the presence of meaningful clusters of multimorbidity, as a basis for anticipating healthcare.