Objective: This study aimed to quantitatively evaluate drug efficacy and identify relevant factors that affect the relief of hot flashes in patients with breast cancer.
Methods: A comprehensive literature search was performed using public databases. Randomized clinical studies on drug therapy for the treatment of hot flashes in patients with breast cancer were identified. A time-effect model was established, and crucial pharmacodynamic parameters, such as maximal efficacy (Emax) and onset time (ET50), were used to reflect the differences in efficacy among the drugs.
Results: Eighteen studies involving 5178 subjects were included. It was found that the baseline of hot flashes was an important factor for the Emax value of drugs. After correcting the baseline to the level of eight times per day, the Emax values of progesterone, selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors (SSRIs/SNRIs), neuroleptic agents, tibolone, phytoestrogen, other types of drugs, and placebo were 8.3(95%CI 6.8, 9.9),5.1(95%CI 4.4, 5.7), 4.4(95%CI 3.6, 5.3), 4.0(95%CI 3.6, 4.3), 3.4(95%CI 2.4, 4.3), 2.5(95%CI 0.8, 4.2), and 2.7(95%CI 2.1, 3.3), respectively. The ET50 of all the drugs were approximately 2-2.5 weeks, which was obviously longer than that of the placebo (1.2 weeks). When compared with the previously reported efficacy characteristics in natural menopausal women, no significant difference was found between the two populations.
Conclusions: Progesterone showed the highest efficacy, followed by SSRIs/SNRIs, neuroleptic agents, and tibolone, while phytoestrogen and other types of drugs showed no efficacy advantages. There is a significant association between the baseline of hot flashes and drug efficacy, while there was no significant difference between breast cancer patients and natural menopausal women.
Keywords: Breast cancer; Hot flashes; Medication guidelines; Model-based meta-analysis.