Clinical differentiation of primary from secondary hyperhidrosis

Area of Science:

• Dermatology
• Clinical Medicine
• Epidemiology

Background:

• Hyperhidrosis (HH) is excessive sweating with primary (idiopathic) and secondary (medication/disease-related) causes.
• Clinical features distinguishing primary from secondary HH are not well-documented.

Purpose of the Study:

• To identify clinical and demographic features that predict a diagnosis of primary versus secondary hyperhidrosis.
• To establish diagnostic criteria for primary hyperhidrosis.

Main Methods:

• Retrospective chart review of 415 patients diagnosed with hyperhidrosis over 13 years (1993-2005).
• Analysis of clinical and demographic data to identify predictors of primary (PHH) versus secondary (SHH) hyperhidrosis.

Main Results:

• SHH (6.7%) was associated with older age (mean 39 vs 27 years), onset after 25 years (55% vs 12.1%), unilateral/asymmetric presentation (OR 51), generalized sweating (OR 18), and nocturnal occurrence (OR 23.2).
• Endocrine disorders (57%) and neurologic diseases (32%) were the most common causes of SHH.
• Asymmetric HH was strongly associated with neurologic disease (OR 63).

Conclusions:

• Statistically derived criteria for PHH include: duration of 6+ months, eccrine-dense sites, bilateral/symmetric, absent nocturnally, weekly episodes, onset ≤25 years, positive family history, and daily activity impairment.
• These criteria demonstrated high sensitivity (0.99) and specificity (0.82) in differentiating PHH from SHH.
• The established criteria may improve clinical management of hyperhidrosis.