Richard Bruton (Dublin Bay North, Fine Gael)
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523. To ask the Minister for Health if he has examined the reports of elevated death rates; and whether any research is being undertaken to evaluate underlying factors. [41033/23]

Stephen Donnelly (Wicklow, Fianna Fail)
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The Department of Health does not produce estimates of excess mortality. However, the Department works closely with the Health Protection Surveillance Centre (HPSC) and other stakeholders to monitor estimates of excess mortality. Excess mortality refers to the number of deaths from all causes during a period of time above and beyond what we would have normally expected to see.

A number of different methodologies have been developed by organisations and academics internationally to try to estimate levels of excess mortality. It is important to note that estimation methods vary, for example in the years used to estimate a baseline, in how they estimate the level of expected deaths, the data source used for ‘actual’ deaths and whether statistical significance tests are applied before reporting deaths as excess. There is therefore no single source of data on estimated excess mortality.

Internationally work is currently underway to improve methods to estimate excess mortality including moving the baseline years used to calculate expected deaths forward from pre-pandemic years. The gap between the current period and the baseline period is relatively wide and growing. The gap is greater than would have been normal practice previously, which impacts on comparability between the current period and the period used to estimate ‘expected’ deaths.

In addition, most estimation methods, including Eurostat and EuroMOMO, do not currently take account of demographic changes such as population change or ageing which may have occurred since the baseline period and which can have a large impact on mortality. EuroMOMO has received four-year funding to further develop their model, including the incorporation of demographic change.

The Health Protection Surveillance Centre (HPSC) has monitored excess mortality in Ireland since 2009, using registered deaths data reported to HPSC on a daily basis from the General Register Office (GRO). HPSC participates in EuroMOMO for Ireland, a European mortality monitoring activity, aiming to detect and measure excess deaths related to seasonal influenza, pandemics and other public health threats. EuroMOMO publish a weekly update of estimates of excess mortality for all participating European countries www.euromomo.eu/graphs-and-maps. This is the primary indicator of excess mortality used in Ireland.

The latest HPSC excess mortality analysis of all registered deaths in Ireland for the 2022/2023 winter period, using the standardised European EuroMOMO algorithm, has shown:

• Excess all-cause mortality over five consecutive weeks (week 51 2022 – week 3 2023), reaching moderate levels of excess during weeks 51 and 52 2022 and week 2 2023 (data attached)
• All-cause, all ages mortality has been below the baseline and within the normal range since week 3 2023.
• EuroMOMO estimates that over the past 12 months, Ireland has experienced excess mortality during five weeks.

EuroMOMO excess mortality estimates (weekly z-scores) for all ages, Ireland, Week 37 2017 – Week 35 2023 www.euromomo.eu/graphs-and-maps#

See attached EuroMOMO_IRL_-z-scores.png

These data are provisional due to the time lag with death registration in Ireland. A country-specific adjustment function was applied to correct for the typical lag in registrations of deaths in Ireland (the legal period for death registration in Ireland is three months). Nonetheless, estimates of excess mortality for the most recent weeks are reported with some uncertainty and should be interpreted with caution.

It is important to note that excess mortality has been observed during previous periods when influenza viruses circulated at high levels in Ireland, for example in winter 2017/2018 which has previously been characterised as a severe flu season, and during certain periods of the COVID-19 pandemic (April 2020 and January 2021).

As Ireland experienced a winter of high levels of influenza cases and hospitalisations, it would not be unexpected to see excess mortality. Influenza activity was at very high levels in Ireland during December 2022 and early/mid-January 2023, with a high number of influenza hospitalisations reported (see www.hpsc.ie/a-z/respiratory/influenza/seasonalinfluenza/surveillance/influenzasurveillancereports/20222023season/). Other important factors that may impact excess mortality include the ongoing COVID-19 pandemic, circulation of other respiratory viruses, impacts of cold weather, and an ageing population.

Excess mortality was also observed in other European countries over the course of winter 2022/2023. In Europe, the overall pooled EuroMOMO estimates of all-cause excess mortality in all age groups for the participating European countries have shown elevated mortality in all age groups for late 2022/early 2023.

Separately, Eurostat publishes monthly estimates of excess mortality for EU (and some non-EU) countries. This data only incudes excess mortality estimates from January 2020 onwards. Eurostat use the following methodology, ‘The excess mortality indicator simply takes the number of people who died from any cause, in a given period, and compares it with a historical baseline from previous years in a period which was not affected by the pandemic. In this case, the baseline consists of the average number of deaths that occurred in each month during the period 2016-2019’.

The methodology does not require a statistically significant difference to report excess deaths. As noted above, it also does not take account of factors such as demographic change. The recent Census 2022 summary results have shown that the number of persons in Ireland aged 65 years and over increased by 22% between 2016 and 2022. Within this category, the highest increases were among those aged 75-84 years (28%) and 85 years and over (25%). Over the same period, the total population only increased by 8.1% with declines in some younger age.

The 22% increase in the population aged 65 years and older in Ireland between 2016 and 2022, was more than double the 10% increase which occurred for the EU27 over the same period. For the 75-84 years age category the difference was greater, with a 3% increase across the EU27 compared with a 28% increase in Ireland. The extent of the demographic changes in Ireland between the baseline period (2016-2019) and the current year (2023) reduces the value of comparing current deaths with deaths in 2016-2019.

In relation to Ireland, it is also important to note that data from 2020 onwards is based on data provided by the CSO based on a web-scraped series from rip.ie. The comparison baseline (2016-2019) is built using official data on registered deaths. Caution is required in interpreting this indicator.

The latest data published by Eurostat (published 9 August 2023 ec.europa.eu/eurostat/statistics-explained/index.php?title=Excess_mortality_-_statistics), refers to deaths in June 2023. Based on the Eurostat methodology, it is estimated that Ireland experienced 13.6% additional deaths in June and has experienced additional deaths every month for the past 12 months (data attached). This means the number of deaths in each month was higher than the average number of deaths in that same month during the years 2016-2019. It does not account for population growth, ageing or other factors impacting on long-term mortality trends.

The Central Statistics Office (CSO) publishes official statistics on mortality in Ireland and publishes quarterly and yearly statistics on registered deaths through their Vital Statistics publications. The latest published data is for deaths registered in Quarter 1 2023 and data is provisional. Data on deaths in each quarter from Quarter 2 2022 to Quarter 1 2023 by cause of death is attached.

The Department of Health is actively monitoring and reviewing all available data on mortality as it becomes available to gain a better insight on the underlying mortality trends and factors influencing these. The Department supports the clear national commitment to learn from the COVID-19 pandemic, in particular with a view to ensuring the State’s preparedness for future public health threats.

Attached