Background

Conventional photodynamic therapy (c-PDT) is a highly effective treatment for actinic keratoses. Besides pain as the main side effect, blood pressure (BP) increases and hypertensive crises may occur during treatment. Reducing the irradiation intensity while keeping the total dose constant (low-irradiance PDT) can achieve a clinically relevant reduction in pain. This study aimed to evaluate the influence of li-PDT on the BP and pulse (PR) during therapy, and the incidence of post-interventional hypertension compared to c-PDT.

Methods

We retrospectively analyzed the treatment data of 79 patients (39 c-PDT and 40 li-PDT). BP and PR measurements were performed in all patients before PDT, at mid-exposure, and immediately after PDT. In addition, the pain was assessed by using the visual analog scale.

Results

Patients treated with li-PDT reported significantly lower pain than those receiving c-PDT (p<0.0005). Additionally, they showed less systolic (SBP) and diastolic (DBP) BP increase (∆SBP: p<0.0005, ∆DBP: p=0.015) and overall lower absolute BP values (SBP: p<0.0005, DBP: p=0.008) compared to c-PDT. They were also significantly less likely to develop post-interventional hypertension (p=0.037) or higher stages of arterial hypertension. Regarding PR, there was no difference in absolute values between both groups, but the increase from onset to half irradiation duration was significantly higher in c-PDT (p=0.013).

Conclusions

Li-PDT is an excellent option to reduce the elevation of arterial BP and decrease the incidence of post-interventional hypertension and hypertensive crisis. This finding has considerable relevance, especially with the risk profile of many PDT patients in mind (advanced age and cardiovascular history).