Biochemical measures and frailty in people with intellectual disabilities

Introduction: People with intellectual disabilities (ID) are earlier frail than people in the general population. Although this may be explained by lifelong unfavourable social, psychological and clinical causes, underlying physiological pathways might be considered too. Biological measures can help identify pathophysiological pathways. Therefore, we examined the association between frailty and a range of serum markers on inflammation, anaemia, the metabolic system, micronutrients and renal functioning. Methods: Participants (n = 757) with borderline to severe ID (50+) were recruited from three Dutch ID care and support services. Results: Frailty was measured with a frailty index, a measure based on the accumulation of deficits. Linear regression analyses were performed to identify associations between frailty and biochemical measures independent of age, gender, level of ID and the presence of Down syndrome. Frailty appears associated with inflammation (IL-6 and CRP), anaemia, metabolic markers (glucose, cholesterol and albumin) and renal functioning (cystatin-C and creatinine). Discussion: These results are in line with results observed in the general population. Future research needs to investigate the causal relation between biochemical measures and frailty, with a special focus on inflammation and nutrition. Furthermore, the possibility to screen for frailty using biochemical measures needs to be used.