A multiyear cross‐sectional study of U.S. national prescribing patterns of first‐generation sedating antihistamines in older adults with skin disease

Abstract

Summary Background First‐generation antihistamines (FGAs) are classified as ‘potentially inappropriate’ for use in older patients (patients aged ≥ 65 years). However, the prevalence of and factors associated with FGA prescription have not been studied. Objectives To examine FGA prescription rates for older patients who visited dermatology offices, and compare them to those for younger patients (patients aged 18–65 years) who visited dermatology offices and those for older patients who visited primary‐care physicians (PCPs). Methods This was a multiyear cross‐sectional observational study using data from the U.S. National Ambulatory Medical Care Survey (2006–2015). Visits by patients aged 18 years or older were included in the study; the data comprised 15 243 dermatology office visits and 66 036 PCP office visits. The main outcome was FGA prescription. Other variables included physician specialty (dermatologist or PCP), patient's age, diagnosis of dermatological conditions and reason for visit. Results For dermatology visits, the overall FGA prescription rate for older patients was similar to that for younger patients (1·5% vs. 1·2%; P = 0·19), even when the diagnosis was dermatitis or pruritus (3·7% vs. 4·8%; P = 0·21) or when itch was a complaint (7·6% vs. 6·7%; P = 0·64). However, the rate of FGA prescription for dermatology visits was lower than that for PCP visits, in analyses matched for patient and visit characteristics (3·9% vs. 7·4%; P = 0·02). Conclusions Our findings suggest that FGAs are overprescribed to older patients but that dermatologists are less likely to prescribe FGAs than PCPs. What's already known about this topic? First‐generation antihistamines (FGAs) have been shown to pose substantial risks to older adults, including cognitive impairment, falls, confusion, dry mouth and constipation. Therefore, FGAs have been classified as ‘potentially inappropriate’ for use in older patients by the American Geriatrics Society. It has also been shown that dermatologists do not always take patient characteristics (e.g. age or life expectancy) into account when deciding on a treatment, instead following a ‘one‐size‐fits‐all’ approach. What does this study add? FGAs are often prescribed during dermatology visits, and prescription rates do not differ between older and younger patients. There were no significant differences in prescription rates when comparing younger and older adults with the same diagnosis or symptom (e.g. dermatitis, pruritus or itch). FGAs are prescribed at higher rates in primary‐care offices than in dermatology offices.

The pharmacology of itch

“…A cross-sectional observational study from the U.S. investigated antihistamine prescriptions following 15,000 dermatology consultations and 66,000 primary care appointments. 7 The study found that FGA prescribing rates were 2-fold higher in primary care than secondary care when comparing matched cohorts. In addition, there was no reduction in prescribing rates in older adults, despite FGA being classified as "potentially inappropriate" in this population.…”

“…As dermatologists we may take for granted use of newer antihistamines that have a lower tendency to cause drowsiness than first‐generation antihistamines (FGAs). A cross‐sectional observational study from the U.S.A. investigated antihistamine prescriptions following 15 000 dermatology consultations and 66 000 primary care appointments 14. The study found that FGA prescribing rates were twofold higher in primary care than secondary care when comparing matched cohorts.…”

Itching for the right treatment

“…Quality use of medicines is a complex task of balancing management of disease while avoiding medication‐related problems. In this issue of the BJD , Cenzer et al ., in their study of first‐generation antihistamine use, raise several important concerns about quality use of medicines for the treatment of skin conditions in older adults. These include selection of the most effective treatment for pruritis and consideration of the potential adverse effects of highly anticholinergic medications.…”

“…Antihistamines are not recommended for the treatment of pruritis arising from other causes but patients may gain some relief from their sedative effects . This may be driving potentially inappropriate first‐generation antihistamine prescription by primary‐care doctors and dermatologists despite antihistamines’ poor benefit‐to‐risk ratio for this indication.…”

“…The issues raised by Cenzer et al . regarding potential overuse of first‐generation antihistamines for the treatment of skin conditions address key principles in the quality use of medicine for older patients that are broadly relevant to all clinicians.…”