Temporal trends in the incidence and mortality of pulmonary arterial hypertension in the United Kingdom over the past 3 decades

Introduction Pulmonary arterial hypertension (PAH) imposes significant burden due to the associated morbidity and mortality. Evaluating the temporal trends in the incidence and mortality of PAH is of paramount importance as it enables risk stratification and prompt recognition of emerging trends. Methods Temporal trends in the incidence and mortality of PAH in the United Kingdom (UK) over the period 1990-2019 were evaluated by retrieving data, including the age-standardized incidence rate (ASIR) and the age-standardized mortality rate (ASMR), from the Global Burden of Disease database. Joinpoint Analysis was utilized tocalculate the Annual Percent Change (APC) and the Average Annual Percent Change(AAPC). Trends were evaluated across the UK, the 4 nations within the UK (England,Wales, Northern Ireland, and Scotland), and across the different regions within England. Results Over a span of 30 years, an estimated total of 6,942 cases of PAH with a female predominance 53.9% were reported across the UK. A statistically significant decline in the ASIR across the UK was noted with an AAPC of -0.16 (95%CI -0.17 to -0.15, p<0.001). Gender stratification revealed a statistically significant decline in the ASIR in both males and females, with the more prominent decrease noted in the latter with an AAPC of -0.23. Stratification on a national level revealed a statistically significant decrease in the ASIR across England, Scotland, Northern Ireland, and Wales with the highest decline observed in Wales with an AAPC of -0.44 (95CI% -0.45 to -0.44, p<0.001). Across England, a statistically significant decline was noted in all of the regions, except for North West England which encountered a statistically insignificant decline with an AAPC of -0.014 (95CI% -0.31 to 0.006, p=0.14). In terms of PAH-related mortalities, an estimated total of 3,381 deaths with a female predominance of 66.6% were reported. A statistically significant decline in the ASMR was noted across the UK with an AAPC of -0.84 (95%CI -0.92 to -0.77, p<0.001). Gender stratification revealed a statistically significant decline in both females and males, with the more prominent decline noted in the latter. Stratification on a national level revealed a statistically significant decline across all 4 nations, with the most prominent decline noted in Northern Ireland with an AAPC of -1.12 (95%CI -1.30 to -1.02, p<0.001). Across England, a statistically significant decline was noted across all regions, with Greater London witnessing the greatest decline with an AAPC of -1.21. Conclusion During 1990-2019, pulmonary arterial hypertension has witnessed a statistically significant decline in incidence and mortality across the UK. These findingswarrant comparison with other developed and developing countries to identify the factors leading to such promising decline.