Abstract
The prevalence of chronic obstructive pulmonary disease (COPD) is rising faster in women in some countries. An observational time trends study was performed to assess the evolution of hospital admissions for COPD in men and women in Spain from 1998 to 2018. ICD-9 diagnostic codes (490-492, 496) from the minimum basic data set of hospital discharges were used. Age-standardised admission rates were calculated using the European Standard Population. Joinpoint regression models were fitted to estimate the annual percent change (APC). In 2018, the age-standardised admission rate per 100,000 population/year for COPD was five times higher in men (384.8, 95% CI: 381.7, 387.9) than in women (78.6, 95% CI: 77.4, 79.9). The average annual percent change (AAPC) was negative over the whole study period in men (-1.7%/year, 95% CI: -3.1, -0.2) but positive from 2010 to 2018 (1.1%/year, 95% CI: -0.8, 2.9). In women, the APC was -6.0% (95%CI: -7.1, -4.9) from 1998 to 2010, but the trend reversed direction in the 2010-2018 period (7.8%/year, 95% CI: 5.5, 10.2). Thus, admission rates for COPD decreased from 1998 to 2010 in both men and women but started rising again until 2018, modestly in men and sharply in women.