The common conditions below are rarely the sole driver of major cognitive impairment. However, they may be responsible for mild cognitive impairment and generally worsen cognition at any level.

• Any uncontrolled medical condition: An uncontrolled medical condition can cause symptoms that impair a patient’s cognition. While there is not a large amount of data to prove that better control of medical conditions significantly improves cognition, we do know there are associations between cognitive impairment and CHF as well as cognitive impairment and CKD (Cognitive Impairment and Heart Failure: Systematic Review and Meta-Analysis; Journal of Cardiac Failure – 2017), among other medical conditions.
  
• Thyroid dysfunction: TSH is a routine lab collected in the work-up for cognitive impairment with the thought that thyroid dysfunction could be a reversible cause of dementia​. However, a 2021 review published in JAMA IM (Association of Thyroid Dysfunction with Cognitive Function; JAMA Intern Med 2021) concludes that subclinical thyroid dysfunction is not associated with cognitive function and proposes revisiting the guidelines that recommend routine screening for thyroid disorders in the work-up for cognitive impairment. In clinical hypothyroidism and hyperthyroidism, changes in cognition can be seen. These conditions should be treated according to the standards.
  
• B12 deficiency: Screening for B12 deficiency in the work-up of cognitive impairment is almost universally recommended​. Several studies have shown a link between B12 deficiency and dementia​. However, treatment with B12 does not necessarily change cognitive function​; the conclusion of this Cochrane review (Vitamin and mineral supplementation for preventing dementia or delaying cognitive decline in people with mild cognitive impairment; Cochcrane Database Syst Rev – 2018) stated: “There was probably little or no effect of B vitamins taken for six to 24 months on episodic memory, executive function, speed of processing, or quality of life.”
  
• OSA and other sleep disorders: OSA is more prevalent in people with dementia than in people without dementia (Obstructive sleep apnea, cognition and Alzheimer’s disease: A systematic review integrating three decades of multidisciplinary research; Sleep Med Rev – 2020), however the link between OSA and cognition is not well understood. We recommend screening for OSA and pursuing evaluation/treatment as necessary.
  
• Hearing loss: Hearing loss is a risk factor for cognitive impairment​ (Association of Age-Related Hearing Loss with Cognitive Function, Cognitive Impairment, and Dementia; JAMA Otolaryngol Head Neck Sug – 2018) . Refer patients for hearing evaluation if there is any suspicion for hearing loss and they have not yet been evaluated.​ If a person already has hearing aids, encourage them to wear their hearing aids as much as possible​.
  
• Vision loss: Visual dysfunction is associated with poor cognitive function (Association of Vision Loss with Cognition in Older Adults; JAMA Ophthalmol – 2017)​. Ask your patients about vision changes and refer them for vision screening if needed​. If a person already had glasses/contacts, encourage use of them.
  
• Depression: Depression has a complicated relationship with dementia: as a mimic, a prodrome, or a complication of dementia (Depression and Dementia: Cause, consequence or coincidence; Maturitas – 2014). We recommend screening and pursuing treatment as necessary.
  
• Medications:
  • Anticholinergic medications: Exposure to anticholinergic medications has been associated with increased odds of cognitive impairment in various studies (Drugs with anticholinergic effects and cognitive impairment, falls, and all-cause mortality in older adults: A systematic review and meta-analysis; British Journal of Clinical Pharmacology – 2015). In this case-control study (Anticholinergic Drug Exposure and the Risk of Dementia: A Nested Case-Control Study), investigators found significant increases in risk of dementia for specific classes of anticholinergic medications: anticholinergic antidepressants, antiparkinson drugs, antipsychotics, bladder antimuscarinic drugs, and antiepileptic drugs.
    • Use this anticholinergic burden calculator to input the medications your patient is on and calculate their ACB (anticholinergic burden). A score of 3 or more means they might be at higher risk of dementia.
  • Benzodiazepine medications: Associations between benzodiazepine medications and the risk of dementia have been found in some studies. In this systematic review and meta-analysis (Association between Development of Dementia and Use of Benzodiazepines: A Systematic Review and Meta-Analysis; Pharmacotherapy – 2018), the results suggest an association, but the authors caution that the evidence was of very low quality.
  • Consider reviewing the Beers list to see if your patient is on any potentially inappropriate medications for older adults.​
    • FYI: The Beers list, updated every several years by the American Geriatrics Society, is intended to help providers consider which medications may cause more harm than good in adults over age 65 
      
• Recent surgery: Changes in cognition can be seen following surgery; up to 10% of older adults may have persistent changes in cognition at 3 months after surgery. The term “post-operative cognitive dysfunction” (POCD) can be used to classify cognitive impairment that starts between one week and one year post-surgery. This cognitive impairment may be transient or may lead to long-term dementia; the relationship between dementia and POCD is not well-established. Much more work needs to be done to develop guidelines for detection, diagnosis, and prevention of POCD. For more, see Postoperative cognitive dysfunction and dementia: what we need to know and do; British Journal of Anaesthesia – 2017