β-Adrenergic Receptor Blockers Reduce the Occurrence of Keloids and Hypertrophic Scars after Cardiac Device Implantation: A Single-Institution Case-Control Study.

Abstract Keloids and hypertrophic scars are characterized by excessive proliferation of fibroblasts; abnormal accumulation of extracellular matrix; and clinical findings of raised, red, itchy, and painful lesions. There are few sufficient interventions for keloids, and the development of new therapeutic agents is urgently needed. Several studies suggest that a therapeutic possibility is β-adrenergic receptor blocker treatment. In this single-center case-control study, patients who had undergone cardiac device implantation 7 to 23 months earlier were identified. The implantation incision scars of the patients were deemed to be normal or abnormal depending on their redness. The cases (abnormal scars) and controls (normal scars) were compared in terms of their β-blocker use rates. Of the 45 eligible patients, 12 and 33 patients were cases and controls, respectively. The cases tended to be less likely to have taken blockers than the controls (25 percent versus 45.5 percent). This difference became significant when the patients whose scars were diagnosed 7 or 8 months after implantation were excluded from the analysis: the age-adjusted odds ratios of the patients who were diagnosed 8 to 23 and 9 to 23 months after implantation were 0.10 (95 percent CI, 0.00 to 0.83; p = 0.0309) and 0.11 (95 percent CI, 0.00 to 0.98; p = 0.047), respectively. β-Blockers may be an effective alternative modality for preventing and treating keloids and hypertrophic scars. Large-scale multicenter prospective studies that use histology to diagnose scars and diagnose the postoperative scars at the most suitable period are needed to confirm the effectiveness of blockers for abnormal scars. Therapeutic, III.