Patients who receive a higher cumulative dose of isotretinoin are no less likely to experience an acne relapse than those who receive a lower cumulative dose, but they are less likely to require a second course of treatment with isotretinoin, according to findings reported in a research letter in the August 2011 issue of the Journal of the American Academy of Dermatology.

Studies in recent years have shown that lower cumulative doses of isotretinoin may increase the risk of acne relapse. This led Dr. Jacquelyn Coloe of NorthShore University HealthSystem, Evanston, Ill., and colleagues to consider whether a higher cumulative dose of isotretinoin could lead to fewer cases of acne relapse and/or retrials.

They conducted a retrospective chart review of 102 patients with acne who were treated with isotretinoin for at least 4 consecutive months and followed for at least 1 year (J. Am. Acad. Dermatol. 2011;65:422-3).

Of the 102 patients, 46 (45.1%) experienced a relapse, which researchers defined as acne that required prescription medication after a course of isotretinoin. Another 16 (15.7%) required a retrial, defined as recurrent acne severe enough to warrant a second course of isotretinoin.

The researchers further analyzed the cumulative dose by weight (mg/kg), follow-up period, treatment duration, and daily dose during the last month of treatment. They found no significant difference between those patients who experienced relapse versus those who did not. However, patients who received less than 218.8 mg/kg were more likely to require a second course of treatment with isotretinoin than those who received higher doses.

On further analysis, they found that female patients had 4.1 times the risk of needing a retrial.

The investigators trial did not grade the severity of side effects.

These results suggest that a higher dose per weight may lead to less severe recurrences of acne and less likelihood of the need for further isotretinoin therapy. "If patients can tolerate higher doses safely, then this approach could result in better long-term outcomes," the researchers wrote.

The study had several limitations, however, the researchers noted. First, the research was a chart review with a relatively small sample size. Second, there was a discrepancy in the follow-up time between groups, with a median 60 months for the group that required retrial versus 24.5 months for those who did not. More rigorous prospective studies are needed to confirm these findings.

The authors made no disclosures.

08/02/11  

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FROM THE JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY

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Major Finding: Patients receiving less than 218.8 mg/kg were more likely to require a second course of treatment with isotretinoin than those who received higher doses.

Data Source: Retrospective chart review of 102 patients treated with isotretinoin.

Disclosures: The authors made no disclosures.