The Duration of Acne Treatment

June 2014 | Volume 13 | Issue 6 | Original Article | 655 | Copyright © June 2014


Karen E. Huang MS,a S. Evan Carstensen BS,a and Steven R. Feldman MD PhDa,b,c

aCenter for Dermatology Research, Department of Dermatology, Wake Forest School of Medicine, Winston-Salem, NC
bDepartment of Pathology, Wake Forest School of Medicine, Winston-Salem, NC
cDepartment of Public Health Sciences, Wake Forest School of Medicine, Winston-Salem, NC

Abstract
BACKGROUND: Acne has a ~90% lifetime prevalence, however the duration of the condition and its treatment is not well characterized. The purpose of this study was to estimate for how long acne patients are treated.
METHODS: Electronic patient records from an academic practice were queried to identify dermatology visits with an acne diagnosis (ICD-9: 706.1) between January 1, 2009 and June 1, 2012. The duration of care for acne treatment was calculated as the time between the earliest and latest visits. Kaplan Meier analyses were used to describe treatment duration.
RESULTS: 1,130 patients had at least one visit acne-related visit to a dermatologist, with 631 (56%) having only one visit and 499 (44%) having multiple visits over the study period. For patients with multiple visits, the mean duration from first to last visit was 0.57 year (95% CI: 0.52, 0.62); 25% ceased visiting in 0.25 year, 50% in 0.40 year, and 75% in 0.64 year.
CONCLUSION: Our study provides a lower limit on the duration of acne treatment. The duration of acne treatment is longer than the duration of typical acne clinical trials. Understanding the duration of the disease can help set patients’ treatment expectations, which may help improve adherence.

J Drugs Dermatol. 2014;13(6):655-656.

INTRODUCTION

Acne has approximately an 85-90% lifetime prevalence, however the duration of the condition is not well characterized.1,2 Understanding the duration of the disease and healthcare utilization for the disease can help set expectations for how long treatment is required. The information can be used for health management planning as well as educating patients, which helps improve adherence.3 This study examined the duration of healthcare resources use among patients with acne, using electronic medical records from a large academic hospital.

METHODS

After receiving IRB approval, the Wake Forest Baptist Hospital Transitional Data Warehouse was queried for dermatology visits linked with an ICD-9 diagnosis code of 706.1 between January 1, 2009 and November 15, 2012. The average duration of time spent visiting a dermatologist for an acne treatment was calculated by taking the difference in days between the earliest and latest visits over this period, and 95% confidence intervals were calculated. Kaplan Meier analyses were used to describe how long subjects remained in the treated cohort overall and by most intensive treatment prescribed: topical products, non-isotretinoin oral products, or isotretinoin. For the Kaplan Meier survival curve for all patients referring to a dermatologist for acne treatment, 95% confidence intervals and 95% equal precision bands were generated. Median times to treatment discontinuation were reported for each treatment group. Kaplan Meier survival curves by most intensive treatment prescribed were generated and compared using a Log-Rank test. Subjects were considered right-censored if their last visit was within the last three months of the study period. Data were analyzed using SAS 9.2 (SAS Institute Inc., Cary, NC).

RESULTS

A total of 3,664 patients had at least one dermatology visit resulting in an acne diagnosis. Of these patients, 1,860 had one visit and 1,804 had multiple visits. For patients with multiple visits, the mean duration between visits was 0.78 year (286 days) with a 95% confidence interval of 0.75-0.82 year (273-299 days). One hundred sixty-three (9%) of the multiple-visit patients were right-censored. Twenty-five percent ceased visiting a dermatologist in 0.27 year, 50% in 0.51 year, and 75% in 1.01 year (Figure 1).
An acne medication prescription was mentioned in 785 records. For single-visit patients, 90, 132, and 13 were correspondingly prescribed topical, non-isotretinoin oral, or isotretinoin medication. For multi-visit patients, 79, 243, and 228 patients were respectively prescribed topical treatments, oral medications excluding isotretinoin, and isotretinoin as the most intensive therapy. Median treatment durations were 0.73 year for the topical group, 1.03 year for the oral medication group, and 0.54 year for the isotretinoin group (Figure 2). Patients not pre-