Are cognitive disorders more common in geriatric diabetic patients? What factors contribute to cognitive decline?
- Cognitive screening is recommended for all geriatric DM patients. Suggested validated screening tests are the Short Portable Mental Status Questionnaire and the clock drawing test. Screening should be repeated on a twice-yearly basis in those who are borderline and annually in those who are negative. In the case of positive screening, a specialist clinical diagnostic assessment is recommended.
- In patients with mild cognitive impairment and dementia, evaluating and treating possible modifiable risk factors is recommended, such as sensory and physical functional disorders, obstructive sleep apnea syndrome, etc.
- Simplification of antidiabetic drug treatment is also recommended in these patients.
2. STRENGTH OF THE RECOMMENDATIONS
The quality of the evidence is moderate. Recommendations are supported by published evidence and best practice (supported by expert opinion).
3. SUPPORTING EVIDENCE
4. AREAS OF UNCERTAINTY AND FUTURE PERSPECTIVES
Despite great efforts to clarify the specific mechanisms through which diabetes-related vascular and metabolic dysfunctions can influence cognitive function, many issues are still unclear. The impact of sensory deficits, which are commonly found in DM patients and can further increase the risk of cognitive disorders, is of particular interest. In this regard, the synergic effect of multiple sensory deficits affecting cognition is needed specifically in geriatric DM populations. In addition, future perspectives should focus on establishing the role that the development of muscle dysfunction and sarcopenia may have on the cognitive health of geriatric DM patients. Finally, the strong association of DM, sensory deficits, and sarcopenia with the frailty syndrome, support the need for new studies exploring how these conditions can interact each other and ultimately impact cognitive performance.
The impact of DM on cognitive function, especially in old age, has been widely demonstrated in recent decades. A recent systematic review and meta-analysis of 144 studies published until June 2019 showed that DM is associated with an increased risk of developing cognitive deficits and dementia by 25-91% 1. The same review showed that prediabetes and changes in glucose metabolism could also significantly increase the incidence of cognitive disorders. The negative effects of DM on cognition are mediated by various mechanisms. Among these, vascular and metabolic dysfunction are the two main pathways through which DM can cause neuronal damage. In the vascular pathway, DM is associated with microvascular and macrovascular complications that can lead to central and peripheral neuropathy and may increase the risk of atherosclerosis and stroke 2,3. In the metabolic pathway, hyperglycemia/hypoglycemia, insulin-resistance, and the accumulation of advanced glycation end-products can increase both oxidative stress and inflammation, interact with Aβ aggregation, and cause further direct and indirect neuronal damage 4-6. Furthermore, the negative impact of DM on cognitive function can be mediated by common comorbidities, such as obstructive sleep apnea syndrome (OSAS), which should be included among the possible factors contributing to neurodegenerative disorders in geriatric DM patients 7,8.
Despite great efforts to clarify the specific mechanisms through which vascular and metabolic dysfunction can influence cognitive function, many issues are still unclear. For instance, the impact of common complications of diabetes, such as sensory deficits and muscular dysfunction, which can further increase the risk of cognitive disorders, is also of particular interest.
Several authors have highlighted that sensory deficits are significantly associated with an increased risk of cognitive impairment and dementia 9. This effect seems to be particularly exacerbated for combined sensory deficits, suggesting a synergic effect of multiple sensory deficits affecting cognition 10-12. Although this issue has been examined in home-dwelling and institutionalized older persons, there is little data on DM patients. However, within the DM population, vascular and metabolic dysfunction can increase the risk of having multiple sensory deficits 13-15, further exacerbating cognitive decline.
Regarding muscle dysfunction, several studies have shown a close link between DM and loss of muscle quality and quantity, which are the main symptoms of sarcopenia 16-18. As underlined in chapter 3 sarcopenia is not an uncommon condition in DM patients 17,19 and may progressively lead to reduced physical functioning and self-sufficiency 20,21. The strong relationship between physical and cognitive functioning 22 and the associations between sarcopenia and cognitive deficits 23 therefore raises the assumption that sarcopenia could be an additional factor that mediates the negative impact of DM on cognitive health.
Finally, another factor to consider in the relationship between DM and cognitive deficits is frailty. Frailty is a condition characterized by reduced resilience to external stressors, which is associated with adverse health outcomes such as disability, institutionalization, and mortality. DM 24,25, sensory deficits 26, and sarcopenia 27,28 are strongly associated with frailty. In turn, frailty can substantially accelerate other age-related degenerative processes, such as cognitive decline 29.
Conflict of interest
The Author declares no conflict of interest.
Figures and tables
|This statement is:⊠ Recommendation (supported by published evidence)⊠ Best practice (supported by expert opinion)||Quality of the evidence (in the case of recommendation):□ Low⊠ Moderate□ High|
- Xue M, Xu W, Ou YN. Diabetes mellitus and risks of cognitive impairment and dementia: a systematic review and meta-analysis of 144 prospective studies. Ageing Res Rev. 2019; 55:100944. DOI
- Luitse MJA, Biessels GJ, Rutten GEHM. Diabetes, hyperglycaemia, and acute ischaemic stroke. Lancet Neurol. 2012; 11:261-271. DOI
- Beckman JA, Creager MA, Libby P. Diabetes and atherosclerosis: epidemiology, pathophysiology, and management. JAMA. 2002; 287:2570-2581. DOI
- Li W, Risacher SL, Gao S. Type 2 diabetes mellitus and cerebrospinal fluid Alzheimer’s disease biomarker amyloid β1-42 in Alzheimer’s Disease Neuroimaging Initiative participants. Alzheimers Dement (Amst). 2017; 10:94-98. DOI
- Kerti L, Witte AV, Winkler A. Higher glucose levels associated with lower memory and reduced hippocampal microstructure. Neurology. 2013; 81:1746-1752. DOI
- Biessels GJ, Strachan MWJ, Visseren FLJ. Dementia and cognitive decline in type 2 diabetes and prediabetic stages: towards targeted interventions. Lancet Diabetes Endocrinol. 2014; 2:246-255. DOI
- Borel AL, Tamisier R, Böhme P. Obstructive sleep apnoea syndrome in patients living with diabetes: which patients should be screened?. Diabetes Metab. 2019; 45:91-101. DOI
- Yaffe K, Laffan AM, Harrison SL. Sleep-disordered breathing, hypoxia, and risk of mild cognitive impairment and dementia in older women. JAMA. 2011; 306:613-619. DOI
- Loughrey DG, Kelly ME, Kelley GA. Association of age-related hearing loss with cognitive function, cognitive impairment, and dementia: a systematic review and meta-analysis. JAMA Otolaryngol Head Neck Surg. 2018; 144:115-126. DOI
- Lyu J, Kim HY. Gender-specific associations of sensory impairments with depression and cognitive impairment in later life. Psychiatry Investig. 2018; 15:926-934. DOI
- Hwang PH, Longstreth WT, Brenowitz WD. Dual sensory impairment in older adults and risk of dementia from the GEM Study. Alzheimers Dement (Amst). 2020; 12:e12054. DOI
- Yamada Y, Denkinger MD, Onder G. Impact of dual sensory impairment on onset of behavioral symptoms in European nursing homes: results from the Services and Health for Elderly in Long-Term Care Study. J Am Med Dir Assoc. 2015; 16:329-333. DOI
- Bainbridge KE, Hoffman HJ, Cowie CC. Diabetes and hearing impairment in the United States: audiometric evidence from the National Health and Nutrition Examination Survey, 1999 to 2004. Ann Intern Med. 2008; 149:1-10. DOI
- Loprinzi PD, Smit E, Pariser G. Association among depression, physical functioning, and hearing and vision impairment in adults with diabetes. Diabetes Spectrum. 2013; 26:6-15. DOI
- Zhang X, Gregg EW, Cheng YJ. Diabetes mellitus and visual impairment: national health and nutrition examination survey, 1999-2004. Arch Ophthalmol. 2008; 126:1421-1427. DOI
- Cruz-Jentoft AJ, Bahat G, Bauer J. Sarcopenia: revised European consensus on definition and diagnosis. Age Ageing. 2019; 48:16-31. DOI
- Kim TN, Park MS, Yang SJ. Prevalence and determinant factors of sarcopenia in patients with type 2 diabetes: the Korean Sarcopenic Obesity Study (KSOS). Diabetes Care. 2010; 33:1497-1499. DOI
- Morley JE, Malmstrom TK, Rodriguez-Mañas L. Frailty, sarcopenia and diabetes. J Am Med Dir Assoc. 2014; 15:853-859. DOI
- Mesinovic J, Zengin A, De Courten B. Sarcopenia and type 2 diabetes mellitus: a bidirectional relationship. Diabetes Metab Syndr Obes. 2019; 12:1057-1072. DOI
- Ferrucci L, Penninx BWJH, Volpato S. Change in muscle strength explains accelerated decline of physical function in older women with high interleukin-6 serum levels. J Am Geriatr Soc. 2002; 50:1947-1954. DOI
- Rolland Y, Czerwinski S, Abellan Van Kan G. Sarcopenia: its assessment, etiology, pathogenesis, consequences and future perspectives. J Nutr Health Aging. 12:433-450. DOI
- Grande G, Triolo F, Nuara A. Measuring gait speed to better identify prodromal dementia. Exp Gerontol. 2019; 124:110625. DOI
- Chang KV, Hsu TH, Wu WT. Association between sarcopenia and cognitive impairment: a systematic review and meta-analysis. J Am Med Dir Assoc. 2016; 17:1164.e7-1164.e15. DOI
- García-Esquinas E, Graciani A, Guallar-Castillón P. Diabetes and risk of frailty and its potential mechanisms: a prospective cohort study of older adults. J Am Med Dir Assoc. 2015; 16:748-754. DOI
- Sinclair AJ, Rodriguez-Mañas L. Diabetes and frailty: two converging conditions?. Can J Diabetes. 2016; 40:77-83. DOI
- Tan BKJ, Man REK, Gan ATL. Is sensory loss an understudied risk factor for frailty? A systematic review and meta-analysis. J Gerontol A Biol Sci Med Sci. 2020; 75:2461-2470. DOI
- Cesari M, Landi F, Vellas B. Sarcopenia and physical frailty: two sides of the same coin. Front Aging Neurosci. 2014; 6:192. DOI
- Fried LP, Tangen CM, Walston J. Frailty in older adults: evidence for a phenotype. J Gerontol A Biol Sci Med Sci. 2001; 56:M146-M156. DOI
- Borges MK, Canevelli M, Cesari M. Frailty as a predictor of cognitive disorders: a systematic review and meta-analysis. Front Med (Lausanne). 2019; 6:26. DOI
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