What are paresthesia and dysesthesia in an older adult with a history of diabetes mellitus (DM)?

Paresthesia and Dysesthesia in Older Adults with Diabetes

Paresthesia refers to abnormal sensations such as tingling, while dysesthesia describes unpleasant sensations of burning and tingling that occur in diabetic peripheral neuropathy, typically resulting from small nerve fiber involvement. 1

Clinical Definitions and Nerve Fiber Involvement

Dysesthesia represents the early symptomatic manifestation of diabetic peripheral neuropathy (DPN) and specifically indicates small fiber involvement. 1 These unpleasant burning and tingling sensations are among the most common early symptoms patients experience when small sensory nerve fibers become damaged by chronic hyperglycemia. 1

Paresthesia encompasses a broader category of abnormal sensations including tingling, numbness, and "pins and needles" feelings that can occur with either small or large fiber involvement. 1

Pathophysiologic Distinction

The type of sensation correlates directly with which nerve fiber class is affected:

• Small fiber dysfunction produces pain and dysesthesia (burning, tingling sensations that are unpleasant) 1
• Large fiber dysfunction causes numbness and loss of protective sensation (LOPS), which paradoxically may be painless but increases risk for foot ulceration 1

Clinical Significance in Older Diabetic Adults

Older adults with diabetes face particular vulnerability to neuropathic symptoms due to the cumulative burden of disease duration and age-related factors. 1 The interaction between age and diabetes duration (age × duration) has been specifically associated with increased risk of microvascular complications including neuropathy. 1

Key Risk Factors in This Population:

• Peripheral neuropathy contributes to increased fall risk in older diabetic adults 1
• Visual impairment from diabetic retinopathy compounds the functional impact 1
• Cognitive impairment may interfere with recognition and reporting of neuropathic symptoms 1
• Polypharmacy increases risk of drug-drug interactions that may worsen or mask neuropathic symptoms 1

Screening and Assessment Requirements

All patients with type 2 diabetes should be assessed for diabetic peripheral neuropathy starting at diagnosis, then annually thereafter. 1 This assessment must include:

• Careful history specifically asking about burning, tingling, or painful sensations 1
• Assessment of temperature or pinprick sensation (tests small fiber function) 1
• Vibration testing with 128-Hz tuning fork (tests large fiber function) 1
• Annual 10-g monofilament testing to identify feet at risk for ulceration 1

Common Clinical Pitfall

Older adults may underreport neuropathic symptoms or attribute them to "normal aging," leading to delayed recognition and treatment. 1 Additionally, elderly patients are less likely to experience typical diabetes symptoms like polyuria due to increased renal threshold for glycosuria and impaired thirst mechanisms. 1 Therefore, clinicians must actively screen rather than wait for patient complaints.

Treatment Implications

Pregabalin, duloxetine, or gabapentin are recommended as initial pharmacologic treatments for neuropathic pain in diabetes. 1 The goal is to reduce pain and improve quality of life, as these symptoms significantly impact functional status in older adults. 1

Management Priorities:

• Optimize glycemic control to prevent progression, though targets should be individualized (A1C 8.0-8.5% for those with multiple comorbidities or functional impairment) 1
• Screen for autonomic neuropathy in patients with microvascular complications 1
• Assess fall risk given the association between peripheral neuropathy and injurious falls 1
• Monitor for loss of protective sensation which increases ulceration risk even when painful symptoms are absent 1