Estimating the Gender Distribution of Patients with Wild-Type Transthyretin Amyloid Cardiomyopathy: A Systematic Review and Meta-Analysis.

INTRODUCTION: This study investigates the gender distribution in patients diagnosed with wild-type transthyretin amyloidosis cardiomyopathy (ATTRwt). METHODS: A systematic review and meta-analysis of the male proportion in diagnosed ATTRwt patients were conducted. To avoid overlapping population, pooled estimates in the primary analysis were based on all unique studies. In secondary analyses, we considered predefined subsets of studies based on study sample size, recruitment years, geography, study design, age at diagnosis, and method of diagnosis. Additional meta-regression analyses were tested for potential determinants of gender distribution. RESULTS: Twenty-eight unique studies (2542 patients) were included in the meta-analysis. Male proportion in patients with ATTRwt was 86.9% (95% confidence interval 81.5-91.6%). Studies, including patients older than 80 years at diagnosis, had a 29.1% (p value < 0.001) lower male proportion compared to studies, including younger patients. After adjusting for age, studies using autopsy as a method of diagnosis had a 21.1% (p value 0.002) lower male proportion compared to other studies. CONCLUSIONS: Studies conducted to date suggest ATTRwt disproportionally affects males. The proportion of males was significantly impacted by the age at diagnosis and method diagnosis, which may suggest important gender-based differences in the clinical manifestation and diagnostic challenges of ATTRwt in females that warrant future research.