NZ’s hidden chronic health burden is even bigger than we thought – new analysis

In New Zealand, more than 80% of healthcare costs go toward caring for people with long-term or chronic conditions.

Startling as that statistic might seem, it won’t be so surprising to those working in our hospital wards and general practices.

Conditions such as diabetes, heart disease and asthma are common, and many people live with two or more at once – something called multimorbidity.

It’s well known this requires ongoing care, often at a high level. What is less understood, however, is just how much of this need is missing from the hospital records health planning and funding greatly rely on.

As these records don’t always capture conditions managed by GPs in the community, it can be difficult to establish the full extent of multimorbidity.

Our recently published research takes us closer to this – and suggests hospital records alone may fail to identify more than half of those found to have multiple long-term conditions.

Building the bigger picture

We examined the health records of 374,071 adults enrolled with general practices belonging to ProCare, a primary health organisation serving the greater Auckland region.

We linked their GP records with national hospitalisation data, looking for evidence of 61 long-term conditions, including cardiovascular disease, diabetes, respiratory illnesses and cancer.

The records covered patients enrolled in January 2014, so our findings provide a historical snapshot rather than a measure of today’s prevalence.

Using hospital records alone, we found 14% of adults had two or more long-term conditions. But when we included information recorded by their GPs, that figure rose to 31%.

This meant another 62,453 people were identified as having multimorbidity only when GP records were taken into account.

Across all age groups, hospital records underestimated multimorbidity more for women than men, with the largest differences generally occurring between ages 55 and 84.

The overall burden also increased markedly with age. More than 60% of people aged 65-74 were living with at least two long-term conditions, rising to nearly 80% among those aged 75-84.

Why do hospital records miss so much?

Many long-term conditions are managed primarily by GPs and other healthcare professionals in the community, without patients needing hospital treatment.

Even when someone is admitted to hospital, conditions unrelated to the reason for their admission may not be recorded.

Among the most common conditions identified through GP records were high blood pressure, joint and spinal disorders, diabetes and chronic respiratory diseases such as asthma.

Managing several conditions at once can be complicated, requiring careful consideration of treatments, possible drug interactions and side effects. In GP clinics, these account for a sizeable share of consultations.

Our findings suggest hospital records capture only part of this workload, leaving much of the care provided in the community unaccounted for when assessing patients’ needs.

What this means for the health system

Our findings have implications for patients, healthcare professionals and those responsible for planning and funding health services.

At present, New Zealand lacks a fully integrated national record of long-term health conditions across general practice and hospitals. Important information held by GPs may therefore not be available to hospital clinicians when patients need treatment.

This can complicate decisions about caring for patients with several long-term conditions, particularly when treatments or medications interact.

Incomplete medical histories might also increase the risk of adverse events, potentially contributing to longer hospital stays or avoidable re-admissions.

There are obvious implications for healthcare planning. Relying heavily on hospital data risks underestimating the demand for ongoing care in the community, along with the workforce and funding needed to provide it.

General practices are already under pressure, while hospital emergency departments face high demand. As New Zealand’s population ages, the number of people living with multiple long-term conditions – and the complexity of their care – is likely to increase.

The unsung care of multimorbidity in the community is happening despite a shortage of GPs, which has long been documented.

And soon, more GPs will be leaving the system than entering it. A 2022 Royal New Zealand College of General Practitioner survey reported that 37% of GPs intended to retire by 2027 and 55% by 2032.

Our research highlights the need to bring together information from general practice and hospitals, giving health planners a more complete understanding of patients’ needs and the resources required to meet them.

The author acknowledges the contribution of Susan Wells, Honorary Professor, School of Population Health, University of Auckland, and Allan Moffitt, Clinical Director, ProCare Health.