Recent trends of invasive mechanical ventilation in older adults: a nationwide population-based study

Background Critical care demand for older people is increasing. However, there is scarce population-based information about the use of life-support measures such as invasive mechanical ventilation (IMV) in this population segment. Objective To examine the characteristics and recent trends of IMV for older adults. Methods Retrospective cohort study on IMV in adults >= 65 years using the 2004-15 Spanish national hospital discharge database. Primary outcomes were incidence, inhospital mortality and resource utilization. Trends were assessed for average annual percentage change in rates using joinpoint regression models. Results 233,038 cases were identified representing 1.27% of all-cause hospitalizations and a crude incidence of 248 cases/100,000 older adult population. Mean age was 75 years, 62% were men and 70% had comorbidities. Inhospital mortality was 48%. Across all ages, about 80% of survivors were discharged home. Incidence rates of IMV remained roughly unchanged over time with an average annual change of -0.2% (95% confidence interval (CI): -0.9, 0.6). Inhospital mortality decreased an annual average of -0.7% (95% CI: -0.5, -1.0), a trend detected across age groups and most clinical strata. Further, there was a 3.4% (95% CI: 3.0, 3.8) annual increase in the proportion of adults aged >= 80 years, an age group that showed higher mortality risk, lower frequency of prolonged IMV, shorter hospital stays and lower costs. Conclusions Overall rates of IMV remained roughly stable among older adults, while inhospitalmortality showed a decreasing trend. There was a notable increase in adults aged >= 80 years, a group with highmortality and lower associated hospital resource use.