"dark spots" in the United States (US), United Kingdom (UK), and Australia from January 2004 to June 2022. We used the chi-squared test to examine seasonal effects and Spearman’s rank test to correlate with search volume.
Of 2,830 acne patients, 16.6% of patients were male and the mean age was 29.9±12.6 years. Seasonal differences in new hyperpigmentation diagnoses were identified among patients prescribed doxycycline (P=0.016), but not among those prescribed minocycline (P=0.885). More new diagnoses occurred in spring compared to winter (P=0.006) among doxycycline users, with most diagnoses occurring in April. Among patients who never received a TCN, hyperpigmentation diagnoses were also seasonally distributed (P<0.001), peaking in May. In this reference population, there were more diagnoses in spring (P=0.003) and summer (P=0.003) than in winter (Figure 1). In the US and UK, there was greater search volume in spring and summer compared to fall and winter (P<0.001). This trend was mirrored in Australia (P<0.001, Figure 2). Doxycycline-associated hyperpigmentation and hyperpigmentation-related searches in the US were correlated (P=0.67, P<0.05).
Of 2,830 acne patients, 16.6% of patients were male and the mean age was 29.9±12.6 years. Seasonal differences in new hyperpigmentation diagnoses were identified among patients prescribed doxycycline (P=0.016), but not among those prescribed minocycline (P=0.885). More new diagnoses occurred in spring compared to winter (P=0.006) among doxycycline users, with most diagnoses occurring in April. Among patients who never received a TCN, hyperpigmentation diagnoses were also seasonally distributed (P<0.001), peaking in May. In this reference population, there were more diagnoses in spring (P=0.003) and summer (P=0.003) than in winter (Figure 1). In the US and UK, there was greater search volume in spring and summer compared to fall and winter (P<0.001). This trend was mirrored in Australia (P<0.001, Figure 2). Doxycycline-associated hyperpigmentation and hyperpigmentation-related searches in the US were correlated (P=0.67, P<0.05).
